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Stem Cell-Seeded Cardiopatch Could Deliver Results for Damaged Hearts

March 8th, 2012 6:37 am

Durham, NC (PRWEB) March 07, 2012

A new type of stem cell-seeded patch has shown promising results in promoting healing after a heart attack, according to a study released today in the journal STEM CELLS Translational Medicine.

Ischemic heart disease, caused by vessel blockage, is a leading cause of death in many western countries. Studies have shown the potential of stem cells in regenerating heart tissue damaged during an attack. But even as the list of candidate cells for cardiac regeneration has expanded, none has emerged as the obvious choice, possibly because several cell types are needed to regenerate both the hearts muscles and its vascular components.

Aside from the choice of the right cell source for tissue regeneration, the best way to deliver the stem cells is up for debate, too, as intravenous delivery and injections can be inefficient and possibly harmful. While embryonic stem cells have shown great promise for heart repairs due to their ability to differentiate into virtually any cell type, less than 10 percent of injected cells typically survive the engraftment and of that number generally only 2 percent actually colonize the heart.

In order for this type of treatment is to be clinically effective, researchers need to find ways to deliver large numbers of stem cells in a supportive environment that can help cells survive and differentiate.

In the current cardiopatch study, conducted by researchers from the Faculty of Medicine of the Geneva University in collaboration with colleagues at the Ecole Polytechnique Federale de Lausanne (EPFL), cardiac-committed mouse embryonic stem cell (mESC) were committed toward the cardiac fate using a protein growth factor called BMP2 and then embedded into a fibrin hydrogel that is both biocompatible and biodegradable. The cells were loaded with superparamagnetic iron oxide nanoparticles so they could be tracked using magnetic resonance imaging, which also enabled the researchers to more accurately assess regional and global heart function.

The patches were engrafted onto the hearts of laboratory rats that had induced heart attacks. Six weeks later, the hearts of the animals receiving the mESC-seeded patches showed significant improvement over those receiving patches loaded with iron oxide nanoparticles alone. The patches had degraded, the cells had colonized the infarcted tissue and new blood vessels were forming in the vicinity of the transplanted patch. Improvements reached beyond the part of the heart where the patch had been applied to manifest globally.

Marisa Jaconi, PhD, of the Geneva University Department of Pathology and Immunology, and Jeffrey Hubbell, PhD, professor of bioengineering at the EPFL, were leaders on the investigative team. Their findings could make a significant impact on how heart patients are treated in the future. Altogether our data provide evidence that stem-cell based cardiopatches represent a promising therapeutic strategy to achieve efficient cell implantation and improved global and regional cardiac function after myocardial infarction, said Jaconi.

###

The full article, Embryonic stem cell-based cardiopatches improve cardiac function in infarcted rats, can be accessed at: http://www.stemcellstm.com/content/early/recent.

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Stem cell repair kit for glaucoma could mean a treatment for the most common cause of blindness

March 8th, 2012 6:36 am

By Fiona Macrae

Last updated at 1:55 AM on 8th March 2012

Important breakthrough: One in ten glaucoma sufferers go blind, due to late diagnosis, drugs not working or the disease being particularly severe (file picture)

A treatment for one of the most common causes of blindness could soon be available.

British researchers have used stem cells to heal the damage caused by glaucoma.

The treatment has only been tested on rats, but scientists say it could be tested on humans by 2015 and in widespread use four years later.

At present one in ten glaucoma sufferers go blind, due to late diagnosis, drugs not working or the disease being particularly severe.

Researchers at University College London took healthy stem cells master cells capable of turning into other types of cell and widely seen as a repair kit for the body from human eyes.

They used a cocktail of chemicals to turn them into retinal ganglion cells those that die in glaucoma. They then injected these into the eyes of rats with glaucoma-like damage.

After just four weeks, the cells had connected with existing nerve cells, and the animals eyes worked 50 per cent better, the journal Stem Cells Translational Medicine reports.

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Transplant without lifetime of drugs?

March 8th, 2012 6:36 am

Lindsay Porter's kidneys weighed 16 pounds before her transplant.

STORY HIGHLIGHTS

(CNN) -- By the time Lindsay Porter had her kidneys removed two years ago, they were bulging -- covered in cysts -- and together weighed 16 pounds.

Her abdominal area was so distended, "I looked nine months pregnant, and people regularly asked when I was due," Porter said.

As she prepared for a transplant to address her polycystic kidney disease, Porter, 47, had mixed feelings -- relief to have found a donor, tinged with resignation. She was looking forward to both a new kidney, and a lifetime on immune system-suppressing drugs.

"You get this brand new shiny kidney, and then they give you drugs that eventually destroy it," said Porter.

But that scenario may eventually change, if results of a new pilot study are replicated in a larger group of patients. The study, published Wednesday in the journal Science Translational Medicine, describes eight kidney transplant patients, including Porter, who received a stem cell therapy that allowed donor and recipient immune cells to coexist in the same body.

The effect, in a handful of those patients, was to trick the recipient's immune system into recognizing the donated kidney as its own.

When it works, patients become a sort of medical rarity called a chimera.

"Chimerism is a condition wherein two different genetic cell populations are present in the body, and both cell types are tolerated," said Dr. Anthony Atala, director of the Institute for Regenerative Medicine at Wake Forest Baptist Medical Center, who was not involved in the study, via e-mail.

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Stem cell research allows for mismatched kidney transplants

March 7th, 2012 9:18 pm

Donating a kidney may save a person's life - but only if the conditions are precise.

Kidney donors must be related and immunologically matched to their donors and even then, the recipient must take a lifetime of anti-rejection medications, which dont guarantee the organ won't be rejected.

But a new clinical trial from Northwestern Memorial Hospital in Chicago, Ill. has shown how stem cells can be used to trick a recipients immune system into believing the new organ has been part of that persons body all along.

The breakthrough has the potential to eliminate both the risks associated with kidney transplantation and the need for anti-rejection medications within one year after surgery.

Its the holy grail of transplantation, said lead author Dr. Joseph Leventhal, transplant surgeon at Northwestern Memorial Hospital and associate professor of surgery and director of kidney and pancreas transplantation at Northwestern University Feinberg School of Medicine in Chicago, Ill. This notion of being able to achieve tolerance through donor derived cells has been around for more than 50 years, but its translation to the clinic has been quite elusive. This article details the first successful attempt of this in mismatched and unrelated kidney recipients.

The research was published Wednesday in the journal Science Translational Medicine, and it is the first study of its kind in which the donor and recipient were not related and did not have to be immunologically matched. Only 25 percent of siblings are immunologically identical, severely limiting the possibility of being a kidney donor.

The procedure worked by extracting a little bit more from the kidney donor than just their kidney. They also donated part of their immune system. About one month before surgery, bone marrow stem cells were collected from the donor and then enriched with facilitating cells becoming stem cells that will ultimately fool the donors immune system allowing the transplant to succeed.

One day after the kidney transplant occurs, the facilitating cell-enriched stem cells are also transplanted in the recipient, which then prompts the formation of stem cells in the bone marrow. This then causes specialized immune cells similar to the donors immune cells to develop, creating a dual bone marrow system environment, so both the donors immune system and the recipients immune system function inside the persons body.

Leventhal said that the ultimate goal is for the recipient to initially take anti-rejection medications but then slowly wean off of them within a year. According to Leventhal, the drugs come with their own share of negative side effects.

The foundation of clinical transplantation revolves around the use of medicines and suppressive drugs to control the immune system, Leventhal said. These drugs have been very successful in reducing the rates of loss of organs due to acute rejection where side effects include increase risk of infection and cancer, and metabolic side effects, such as the increase risk of hypertension and bone disease. But the drugs themselves are potentially harmful to the organs we transplant. Despite our ability to reduce rates of acute rejection, most individuals go on to lose organs because of chronic (long-term) rejection.

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Transplant without lifetime of drugs?

March 7th, 2012 9:17 pm

Lindsay Porter's kidneys weighed 16 pounds before her transplant.

STORY HIGHLIGHTS

(CNN) -- By the time Lindsay Porter had her kidneys removed two years ago, they were bulging -- covered in cysts -- and together weighed 16 pounds.

Her abdominal area was so distended, "I looked nine months pregnant, and people regularly asked when I was due," Porter said.

As she prepared for a transplant to address her polycystic kidney disease, Porter, 47, had mixed feelings -- relief to have found a donor, tinged with resignation. She was looking forward to both a new kidney, and a lifetime on immune system-suppressing drugs.

"You get this brand new shiny kidney, and then they give you drugs that eventually destroy it," said Porter.

But that scenario may eventually change, if results of a new pilot study are replicated in a larger group of patients. The study, published Wednesday in the journal Science Translational Medicine, describes eight kidney transplant patients, including Porter, who received a stem cell therapy that allowed donor and recipient immune cells to coexist in the same body.

The effect, in a handful of those patients, was to trick the recipient's immune system into recognizing the donated kidney as its own.

When it works, patients become a sort of medical rarity called a chimera.

"Chimerism is a condition wherein two different genetic cell populations are present in the body, and both cell types are tolerated," said Dr. Anthony Atala, director of the Institute for Regenerative Medicine at Wake Forest Baptist Medical Center, who was not involved in the study, via e-mail.

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Internationally Recognized Leukemia Physician and Researcher to Lead Sylvester Comprehensive Cancer Center

March 7th, 2012 6:53 pm

MIAMI--(BUSINESS WIRE)--

Stephen D. Nimer, M.D., one of the worlds premier leukemia and stem cell transplant researchers and clinicians, has been named the new director of the Sylvester Comprehensive Cancer Center.

Nimer, the Alfred P. Sloan Chair in Cancer Research at Memorial Sloan-Kettering Cancer Center, will assume the key University of Miami Miller School of Medicine and UHealth-University of Miami Health System post this spring, bringing 30 years of pioneering research and clinical experience and an unquenchable passion for improving the lives of patients with cancer, and their families.

The focus will not be solely on taking care of the cancer, it will be on taking care of the patient, said Nimer, whose patient-centered philosophy has won him as much acclaim as his clinical and laboratory accomplishments. That means trying to understand as fully as possible each patients cancer the biology driving the cancer, and the impact of the cancer on the patients life in order to develop a personalized therapeutic approach suited to each individual.

Pascal J. Goldschmidt, M.D., Senior Vice President for Medical Affairs and Dean of the Miller School, and CEO of UHealth, said Nimer, who headed the Division of Hematologic Oncology at Sloan-Kettering for a dozen years, is the ideal physician-scientist to lead Sylvester into its third decade and to designation as one of the nations official comprehensive cancer centers by the NIHs National Cancer Institute.

Stephen possesses a unique combination of outstanding clinical skills and visionary scientific acumen in cancer research that will lead Sylvester to become the next top comprehensive cancer center in the U.S., Dean Goldschmidt said. He brings a true patient-centered approach to clinical care and leading-edge research that makes a real difference for our fellow humans. Cancer patients across South Florida and around the world will benefit from his expertise and leadership.

Dr. Nimer will be a spectacular leader for the Sylvester Comprehensive Cancer Center, said UM President Donna E. Shalala.This is a momentous development for the Miller School, the University of Miami, and all of South Florida.

Joseph Rosenblatt, M.D., who has served as interim director of Sylvester, said Dr. Nimers arrival will allow Sylvester to find its rightful place among the worlds premier cancer centers, and his leadership will usher in a new era for our cancer center, which I and our faculty anticipate with great enthusiasm.

Nimer, currently vice chair for faculty development at Sloan-Ketterings Department of Medicine, plans to develop and expand a number of services at Sylvester, including programs for breast cancer, lung cancer, prostate cancer and hematological malignancies, among others. He also plans to recruit more than 30 new scientists and physicians, develop key core facilities and expand the clinical and laboratory research capabilities.

He specifically hopes to recruit experts in areas such as bone marrow transplantation, mouse models of human cancer, and molecular diagnostics, as well as additional surgeons skilled in complex, curative and restorative procedures, such as breast reconstruction. He also will expand efforts in cancer prevention, screening and early diagnosis and in identifying those factors that predispose people to develop cancer.

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Stem Cell-Seeded Cardiopatch Could Deliver Results for Damaged Hearts

March 7th, 2012 6:53 pm

A new type of stem cell-seeded patch has shown promising results in promoting healing after a heart attack, according to a study released today in the journal STEM CELLS Translational Medicine.

Durham, NC (PRWEB) March 07, 2012

Ischemic heart disease, caused by vessel blockage, is a leading cause of death in many western countries. Studies have shown the potential of stem cells in regenerating heart tissue damaged during an attack. But even as the list of candidate cells for cardiac regeneration has expanded, none has emerged as the obvious choice, possibly because several cell types are needed to regenerate both the hearts muscles and its vascular components.

Aside from the choice of the right cell source for tissue regeneration, the best way to deliver the stem cells is up for debate, too, as intravenous delivery and injections can be inefficient and possibly harmful. While embryonic stem cells have shown great promise for heart repairs due to their ability to differentiate into virtually any cell type, less than 10 percent of injected cells typically survive the engraftment and of that number generally only 2 percent actually colonize the heart.

In order for this type of treatment is to be clinically effective, researchers need to find ways to deliver large numbers of stem cells in a supportive environment that can help cells survive and differentiate.

In the current cardiopatch study, conducted by researchers from the Faculty of Medicine of the Geneva University in collaboration with colleagues at the Ecole Polytechnique Federale de Lausanne (EPFL), cardiac-committed mouse embryonic stem cell (mESC) were committed toward the cardiac fate using a protein growth factor called BMP2 and then embedded into a fibrin hydrogel that is both biocompatible and biodegradable. The cells were loaded with superparamagnetic iron oxide nanoparticles so they could be tracked using magnetic resonance imaging, which also enabled the researchers to more accurately assess regional and global heart function.

The patches were engrafted onto the hearts of laboratory rats that had induced heart attacks. Six weeks later, the hearts of the animals receiving the mESC-seeded patches showed significant improvement over those receiving patches loaded with iron oxide nanoparticles alone. The patches had degraded, the cells had colonized the infarcted tissue and new blood vessels were forming in the vicinity of the transplanted patch. Improvements reached beyond the part of the heart where the patch had been applied to manifest globally.

Marisa Jaconi, PhD, of the Geneva University Department of Pathology and Immunology, and Jeffrey Hubbell, PhD, professor of bioengineering at the EPFL, were leaders on the investigative team. Their findings could make a significant impact on how heart patients are treated in the future. Altogether our data provide evidence that stem-cell based cardiopatches represent a promising therapeutic strategy to achieve efficient cell implantation and improved global and regional cardiac function after myocardial infarction, said Jaconi.

###

The full article, Embryonic stem cell-based cardiopatches improve cardiac function in infarcted rats, can be accessed at: http://www.stemcellstm.com/content/early/recent.

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Influencing stem cell fate

March 7th, 2012 2:01 pm

Public release date: 6-Mar-2012 [ | E-mail | Share ]

Contact: Megan Fellman fellman@northwestern.edu 847-491-3115 Northwestern University

Northwestern University scientists have developed a powerful analytical method that they have used to direct stem cell differentiation. Out of millions of possibilities, they rapidly identified the chemical and physical structures that can cue stem cells to become osteocytes, cells found in mature bone.

Researchers can use the method, called nanocombinatorics, to build enormous libraries of physical structures varying in size from a few nanometers to many micrometers for addressing problems within and outside biology.

Those in the fields of chemistry, materials engineering and nanotechnology could use this invaluable tool to assess which chemical and physical structures -- including size, shape and composition -- work best for a desired process or function.

Nanocombinatorics holds promise for screening catalysts for energy conversion, understanding properties conferred by nanostructures, identifying active molecules for drug discovery or even optimizing materials for tissue regeneration, among other applications.

Details of the method and proof of concept is published in the Proceedings of the National Academy of Sciences.

"With further development, researchers might be able to use this approach to prepare cells of any lineage on command," said Chad A. Mirkin, who led the work. "Insight into such a process is important for understanding cancer development and for developing novel cancer treatment methodologies."

Mirkin is the George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences and professor of medicine, chemical and biological engineering, biomedical engineering and materials science and engineering. He also is the director of Northwestern's International Institute for Nanotechnology (IIN).

The new analytical method utilizes a technique invented at Northwestern called polymer pen lithography, where basically a rubber stamp having as many as 11 million sharp pyramids is mounted on a transparent glass backing and precisely controlled by an atomic force microscope to generate desired patterns on a surface. Each pyramid -- a polymeric pen -- is coated with molecules for a particular purpose.

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If Canada's game is hockey, its science is stem cells

March 7th, 2012 2:01 pm

alan bernstein From Wednesday's Globe and Mail Published Wednesday, Mar. 07, 2012 2:00AM EST

Most Canadians are unaware that two of their own a lanky physics whiz from Alberta and a rumpled Shakespeare-quoting MD from Toronto made a discovery 50 years ago that transformed the understanding of human biology and opened new doors to the treatment of cancer and other diseases.

Toiling away in labs atop Torontos old Princess Margaret Hospital, James Edgar Till and Ernest Armstrong (Bun) McCulloch proved that a single rare cell could produce the red blood cells, white blood cells and platelets needed to make blood, while simultaneously reproducing itself. Dr. Till and Dr. McCulloch originally called the cell a colony-forming unit. Today, its better known as a stem cell.

A great new book, Dreams and Due Diligence, by Joe Sornberger, tells the story. Still, that so few of us know let alone celebrate the fact that the stem cell is a Canadian discovery is baffling. Canada founded the entire field of stem-cell science. We have done much of the heavy lifting for decades: discovering neural stem cells, skin stem cells and cancer stem cells. If hockey is Canadas game, stem-cell science is Canadas science. Not knowing about Dr. Till and Dr. McCulloch is not knowing about Maurice Richard and Wayne Gretzky.

The way it happened didnt help. Their original paper was published in an obscure journal, Radiation Research, in 1961. Public interest went viral only after American James Thomson isolated human embryonic stem cells in 1998, which simultaneously raised hopes that stem cells could be used to repair any damaged cell in the body and ethical concerns that doing so would encourage the destruction of human embryos.

In 2002, the Canadian Institutes of Health Research developed guidelines for all stem-cell research carried out in Canada with its funds. These guidelines have become the gold standard for other countries, including the United States.

Whats even more remarkable is that Canada does such groundbreaking research on a dime. The all in investment in stem-cell research in Canada public, private and charitable funding is about $75-million. This support is provided by Canadians through taxes, donations to health charities and the generosity of community leaders individuals such as Robert and Cheryl McEwen of Toronto and the late Harley Hotchkiss of Calgary. But we still seriously lag behind California, which, with roughly the same population as Canada, has committed $3-billion over 10 years for stem-cell research.

How much further Canadas star scientists can go, however, is in doubt. According to the Stem Cell Network, there are 40 to 50 early-phase clinical trials using transplanted cells ready to roll out over the next four years. All are currently unfunded.

Prime Minister Stephen Harper has said his government will continue to make the key investments in science and technology but bemoaned Canadas less-than-optimal results for those investments. Stem-cell research has already proved itself a sound investment: Dr. Till and Dr. McCullochs work formed the basis of the bone marrow transplantation program at Princess Margaret Hospital that alone has saved thousands of lives. But it will take more than government funding: Private industry and private citizens also need to support life-saving research.

Canadians have good reason to be proud of our countrys contributions to health research and medicine. Two stand out as landmarks: the discovery of insulin in the 1920s and the discovery of stem cells in the 1960s. On Wednesday, at a dinner that brings together many of the countrys leading figures in business, the arts, entertainment, sports and science, the Canadian Stem Cell Foundation will be launched. The event will look back at that great discovery 50 years ago and look forward to ensure that Canadians continue to contribute to stem-cell research and its application to human disease.

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Influencing stem cell fate: New screening method helps scientists identify key information rapidly

March 7th, 2012 2:01 pm

Researchers can use the method, called nanocombinatorics, to build enormous libraries of physical structures varying in size from a few nanometers to many micrometers for addressing problems within and outside biology.

Those in the fields of chemistry, materials engineering and nanotechnology could use this invaluable tool to assess which chemical and physical structures -- including size, shape and composition -- work best for a desired process or function.

Nanocombinatorics holds promise for screening catalysts for energy conversion, understanding properties conferred by nanostructures, identifying active molecules for drug discovery or even optimizing materials for tissue regeneration, among other applications.

Details of the method and proof of concept is published in the Proceedings of the National Academy of Sciences.

"With further development, researchers might be able to use this approach to prepare cells of any lineage on command," said Chad A. Mirkin, who led the work. "Insight into such a process is important for understanding cancer development and for developing novel cancer treatment methodologies."

Mirkin is the George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences and professor of medicine, chemical and biological engineering, biomedical engineering and materials science and engineering. He also is the director of Northwestern's International Institute for Nanotechnology (IIN).

The new analytical method utilizes a technique invented at Northwestern called polymer pen lithography, where basically a rubber stamp having as many as 11 million sharp pyramids is mounted on a transparent glass backing and precisely controlled by an atomic force microscope to generate desired patterns on a surface. Each pyramid -- a polymeric pen -- is coated with molecules for a particular purpose.

In this work, the researchers used molecules that bind proteins found in the natural cell environment, such as fibronectin, which could then be attached onto a substrate in various patterns. (Fibronectin is a protein that mediates cell adhesion.) The team rapidly prepared millions of textured features over a large area, which they call a library. The library consisted of approximately 10,000 fibronectin patterns having as many as 25 million features ranging in size from a couple hundred nanometers to several micrometers.

To make these surfaces, they intentionally tilt the stamp and its array of pens as the stamp is brought down onto the substrate, each pen delivering a spot of molecules that could then bind fibronectin. The tilt results in different amounts of pressure on the polymeric pens, which dictates the feature size of each spot. Because the pressure varies across a broad range, so does the feature size.

The researchers then introduced mesenchymal stem cells, or MSCs, to the library of millions of fibronectin features. (MSCs are multipotent stem cells that can differentiate into a variety of other cell types.)

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Scientists Repair Eyesight Using Human Cornea From Stem Cells

March 7th, 2012 2:01 pm

Constant shortage of donated corneas have led researchers in Sweden and Spain to explore the possibilities of cultivating corneas from human stem cells.

Two separate studies from the University of Navarra Hospital, Spain and Sahlgrenska Academy University of Gothenburg, Sweden, have attempted to cue in on developing the "epithelial cells" that keep the cornea in its transparent form.

While Swedish scientists have grown stem cells on human corneas, their Spanish counterparts have regenerated the corneal epithelium using cells from the healthy limbus of patients with corneal damage.

A corneal transplant is the only way to prevent total blindness. The result is that nearly 100,000 corneal implants are impacted globally each year. The process calls for replacing the damaged cornea with a healthy and transparent one, relying heavily on donors. Religious or political views have also attacked the medical outcomes of corneal implants adding to long waiting periods for donor-led corneal transplants.

Swedish Scientists Grow Cornea in the Laboratory

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In a first-time effort, scientists at the Sahlgrenska Academy have grown stem cells on human corneas which could perhaps do away with donated corneas in the long run.

The Swedish study published in the journal Acta Ophthalmologica explored ways to develop "epithelial cells" using laboratory cultures for 16 days, which were further cultured on the human cornea for another six days.

Lead scientists Charles Hanson and Ulf Stenevi used defective corneas from the ophthalmology clinic at Sahlgrenska University Hospital in Mlnda for their experiment.

"Similar experiments have been carried out on animals, but this is the first time that stem cells have been grown on damaged human corneas. It means that we have taken the first step towards being able to use stem cells to treat damaged corneas," said Hanson.

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Stem cells 'could repair damaged cornea'

March 7th, 2012 2:01 pm

Washington, Mar 6 : Researchers have for the first time successfully cultivated stem cells on human corneas, which may eliminate the need for donators in the long run.

The damaged and cloudy cornea that is turning the patient blind is replaced with a healthy, transparent one.

But the procedure requires a donated cornea, and there is a severe shortage of donated material. This is particularly the case throughout the world, where religious or political views often hinder the use of donated material.

Scientists at the Sahlgrenska Academy, University of Gothenburg, have taken the first step towards replacing donated corneas with corneas cultivated from stem cells.

Scientists Charles Hanson and Ulf Stenevi have used defective corneas obtained from the ophthalmology clinic at Sahlgrenska University Hospital in Molndal.

Their study shows how human stem cells can be caused to develop into what are known as 'epithelial cells'after 16 days' culture in the laboratory and a further 6 days' culture on a cornea. It is the epithelial cells that maintain the transparency of the cornea.

"Similar experiments have been carried out on animals, but this is the first time that stem cells have been grown on damaged human corneas. It means that we have taken the first step towards being able to use stem cells to treat damaged corneas," said Charles Hanson.

"If we can establish a routine method for this, the availability of material for patients who need a new cornea will be essentially unlimited. Both the surgical procedures and the aftercare will also become much more simple," said Ulf Stenevi.

The study has been published in the journal Acta Ophthalmologica. (ANI)

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Will StemCells Walk The Talk?

March 7th, 2012 2:01 pm

3/7/2012 5:12 AM ET (RTTNews) - Stem cells have set the scientific world agog because it has been proposed as candidates to treat a myriad of diseases ranging from alzheimer's to arthritis, blindness, burns, cancer, diabetes, heart disease, liver disorders, multiple sclerosis, parkinson's, spinal cord injury and stroke.

Engaged in the development of novel stem cell therapeutics targeting diseases of the central nervous system and liver is clinical-stage company StemCells Inc. (STEM: News ).

For readers who are new to this Palo Alto, California-based company, here's what to expect in the coming months...

StemCells' lead product candidate is HuCNS-SC cells, a highly purified composition of human neural stem cells, currently in clinical development for spinal cord injury and for Pelizaeus-Merzbacher Disease, or PMD, a fatal myelination disorder in children.

A phase I/II clinical trial of HuCNS-SC cells in chronic spinal cord injury was initiated by the company last March. The trial, which is the world's first neural stem cell trial in spinal cord injury, is designed to enroll patients with thoracic (chest-level) neurological injuries with progressively decreasing severity of injury in three sequential cohorts.

The first patient in the trial was successfully transplanted with the company's proprietary HuCNS-SC adult neural stem cells last September, and enrollment in the first cohort of the spinal cord injury trial was completed last December. Following transplantation, the patients are being evaluated regularly over a 12-month period in order to monitor and evaluate the safety and tolerability of the HuCNS-SC cells.

The trial, which is currently open for enrollment for the remaining cohorts, is being conducted in Switzerland at the Balgrist University Hospital, University of Zurich.

In November 2011, Geron Corp. (GERN), the first company to get FDA approval for a clinical trial of an embryonic stem cell-based therapy, abandoned its phase I stem cell trial in patients paralyzed by spinal cord injuries - largely because of financial reasons.

The difference between the spinal cord injury trials of StemCells and Geron lies in the type of stem cells being evaluated. While Geron used human embryonic stem cells to treat spinal cord injuries in its trial, StemCells is using tissue-derived "adult" (non-embryonic) stem cells in its trials.

Yet another trial of StemCells that is underway is a phase I trial evaluating the safety and preliminary efficacy of HuCNS-SC cells as a treatment for Pelizaeus-Merzbacher Disease that primarily affects infants and young children.

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BGI Demos Single-Cell Exome Sequencing Method on Tumor Cell Lines, Patient Samples

March 7th, 2012 2:00 pm

By Monica Heger

Researchers at BGI have published two papers in Cell outlining a single-cell exome sequencing technique that they demonstrated on cell lines, a previously sequenced genome, and cancer patient samples.

The papers show that single-cell analysis can provide a much finer-grained genetic characterization of heterogeneous tissues than bulk tissue sequencing and also point toward the use of the method in areas beyond cancer, such as stem cell research and preimplantation genetic diagnosis, according to the BGI researchers.

Moving forward, the team plans to improve the technique and use it to analyze single cells from different cancer types to study "metastasis, recurrence, and [tumors] before and after therapy," Luting Song, project manager at BGI and a co-author on the papers, told In Sequence in an e-mail.

Single-cell sequencing is thought to be especially useful in cancer samples because tumors are heterogeneous and bulk sequencing may miss rare clonal types. Additionally, sequencing individual cells could help study tumor evolution or be used to monitor relapse by sequencing circulating tumor cells in patients' blood.

However, sequencing single cells is tricky because it is difficult to capture the entire genome of a single cell and amplification strategies introduce bias. Nevertheless, a number of researchers and companies have been working on strategies to sequence single cells, including a team from Cold Spring Harbor Laboratory, which developed a strategy that uses degenerate oligonucleotide-primed PCR to amplify the genome (IS 5/18/2010), and Rubicon Genomics, which uses a technique called thermal cycle library formation that enables the creation of multiple copies of a library from one template strand (IS 3/22/2011).

The BGI team described its method in two papers published in Cell last week. In one, the researchers first validated the approach in two lymphoblastoid cell lines, and then performed single-cell exome sequencing on 90 cells from a patient with a myeloproliferative tumor.

In the second paper, the team demonstrated the single-cell exome sequencing method on 25 cells from a patient with clear cell renal cell carcinoma.

The BGI method relies on multiple displacement amplification, which uses the enzyme phi29 to amplify the DNA in a linear fashion. According to Song, compared to the degenerate oligonucleotide-primed PCR method, MDA generates larger amplicons on average 10 kilobases compared to 1 kilobase with DOP which "results in significantly higher genome recovery" and "allows greater resolution."

The greater resolution of MDA enables single-nucleotide variants to be called, while DOP can only reliably call copy number variations, Song added. The CSHL team that initially published the DOP method is now using it to analyze copy number variation from prostate cancer patients.

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Harvard Bioscience Comments on the Passing of Christopher Lyles

March 7th, 2012 2:00 pm

HOLLISTON, Mass., March 6, 2012 (GLOBE NEWSWIRE) -- Harvard Bioscience, Inc. (Nasdaq:HBIO - News), a global developer, manufacturer, and marketer of a broad range of tools to advance life science research and regenerative medicine is deeply saddened to learn of the passing of Mr. Christopher Lyles. Mr. Lyles was a recent recipient of a tracheal transplant regenerated in a Harvard Bioscience InBreath Bioreactor. Currently, we do not know the cause of Mr. Lyle's death. Our thoughts are with his family at this time. His family has released the following statement:

"We, the family of Christopher Lyles, sorrowfully inform you that Christopher passed away this morning, March 5, 2012. Christopher was a recipient and strong advocate of stem cell therapy. We do not want his journey to be in vain. We hope his bravery will pave the way for further research and development and acceptance of stem cell based therapies in the United States. We would like to thank everyone for their thoughts and prayers throughout Christopher's trailblazing journey."

About Harvard Bioscience

Harvard Bioscience ("HBIO") is a global developer, manufacturer and marketer of a broad range of specialized products, primarily apparatus and scientific instruments, used to advance life science research and regenerative medicine. We sell our products to thousands of researchers in over 100 countries primarily through our 850 page catalog (and various other specialty catalogs), our website, through distributors, including GE Healthcare, Thermo Fisher Scientific and VWR, and via our field sales organization. HBIO has sales and manufacturing operations in the United States, the United Kingdom, Sweden, Germany and Spain with additional facilities in France and Canada. For more information, please visit http://www.harvardbioscience.com.

The Harvard Bioscience, Inc. logo is available at http://www.globenewswire.com/newsroom/prs/?pkgid=6426

Forward-looking Statements

The statements made in this press release that are not statements of historical fact are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. You can identify these forward-looking statements by our use of such words as "will," "guidance," "objectives," "optimistic," "potential," "future," "expect," "plans," "estimates," "continue," "drive," "strategy," "crucial," "potential," "potentially," "growth," "long-term," "projects," "projected," "produce," "intends," "believes," "goals," "sees," "seek," "develop," "possible," "new," "enabling," "emerging," "opportunity," "pursue" and similar expressions that do not relate to historical matters. Forward-looking statements in this press release may include, but are not limited to, statements or inferences about the HBIO's or management's beliefs or expectations, the field of regenerative medicine, opportunities or potential opportunities in the field of regenerative medicine, HBIO's business strategy, the positioning of HBIO for growth, the market demand and opportunity for HBIO's current products or products it is developing or intends to develop, and HBIO's plans, objectives and intentions that are not historical facts.

These statements involve known and unknown risks, uncertainties and other factors that may cause HBIO's actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. Factors that may cause HBIO's actual results, performance or achievements to differ materially from those in the forward-looking statements include, but are not limited to, HBIO's failure to successfully expand its product offerings, introduce new products or commercialize new technologies, including in the field of regenerative medicine, decreased demand for the HBIO's products, including products in the field of regenerative medicine, due to changes in our customers' needs, our ability to obtain regulatory approvals, including FDA approval, for our products, including any products in the field of regenerative medicine, the current size or anticipated size of the regenerative medicine market, the existence and size of opportunities in the regenerative medicine market, our financial position, plus risk factors set forth under the heading "Item 1A. Risk Factors" in HBIO's Annual Report on Form 10-K for the fiscal year ended December 31, 2010 or described in HBIO's other public filings. HBIO's results may also be affected by factors of which HBIO is not currently aware. HBIO may not update these forward-looking statements, even though its situation may change in the future, unless it has obligations under the federal securities laws to update and disclose material developments related to previously disclosed information.

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Stanford scientists develop gene therapy approach to grow blood vessels in ischemic limbs

March 7th, 2012 1:58 pm

Public release date: 6-Mar-2012 [ | E-mail | Share ]

Contact: Cody Mooneyhan cmooneyhan@faseb.org 301-634-7104 Federation of American Societies for Experimental Biology

Bethesda, MDA new research discovery by a team of Stanford and European scientists offers hope that people with atherosclerotic disease may one day be able to avoid limb amputation related to ischemia. A new research report appearing online in the FASEB Journal suggests that the delivery of genes for two molecules naturally produced by the body, called "PDGF-BB" and "VEGF" may successfully cause the body to grow new blood vessels that can save ischemic limbs.

"We hope that our findings will ultimately develop into a safe and effective therapy for the many patients, suffering from blocked arteries in the limbs, who are currently not adequately treated by surgery or drugs," said Helen M. Blau, Ph.D., a senior researcher involved in the work and Associate Editor of the FASEB Journal from the Baxter Laboratory for Stem Cell Biology at the Institute for Regenerative Medicine and Stem Cell Biology at Stanford. "This could help avoid the devastating consequences of limb amputations for both patients and their families."

To make this discovery, Blau and colleagues, including Andrea Banfi (now at Basel University), introduced the genes for PDGF-BB and VEGF into the muscles of mice, either independently or together. When high doses of VEGF alone were produced, they caused the growth of vascular tumors. When the two factors were produced in unbalanced amounts, tumor growth also occurred. When VEGF and PDGF were delivered in a fixed ratio relative to one another, however, no tumors occurred, and blood flow was restored to ischemic muscle tissue and damage repaired without any toxic effects. To achieve a "balanced" delivery of PDGF-BB and VEGF, scientists placed both genes in a single gene therapy delivery mechanism, called a "vector."

Although the report shows the feasibility of growing robust and safe new blood vessels that restore blood flow to diseased tissues, Blau points out that "there are multiple challenges to correcting peripheral vasculature disease by using proangiogenic gene therapy strategies. Two important challenges are what to deliver and how to get it to where it can have beneficial effects. Clinical success will require both delivering a gene therapy construct that encodes for effective angiogenic factors and ensuring that the sites of delivery are where the construct can have the greatest clinical benefit."

"This ingenious work, based on the latest techniques of molecular biology, tells us that it is possible to reinvigorate parts of our body that can't get enough blood to keep them going," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal. "The next question is whether this approach will work in humans and exactly how to deliver the new treatment to places that need it the most."

###

Receive monthly highlights from the FASEB Journal by e-mail. Sign up at http://www.faseb.org/fjupdate.aspx. The FASEB Journal is published by the Federation of the American Societies for Experimental Biology (FASEB) and is the most cited biology journal worldwide according to the Institute for Scientific Information. In 2010, the journal was recognized by the Special Libraries Association as one of the top 100 most influential biomedical journals of the past century. FASEB is composed of 26 societies with more than 100,000 members, making it the largest coalition of biomedical research associations in the United States. Celebrating 100 Years of Advancing the Life Sciences in 2012, FASEB is rededicating its efforts to advance health and well-being by promoting progress and education in biological and biomedical sciences through service to our member societies and collaborative advocacy.

Details: Andrea Banfi, Georges von Degenfeld, Roberto Gianni-Barrera, Silvia Reginato, Milton J. Merchant, Donald M. McDonald, and Helen M. Blau. Therapeutic angiogenesis due to balanced single-vector delivery of VEGF and PDGF-BB. FASEB J. doi:10.1096/fj.11-197400 ; http://www.fasebj.org/content/early/2012/03/05/fj.11-197400.abstract

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Stanford scientists develop gene therapy approach to grow blood vessels in ischemic limbs

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Gene therapy approach to grow blood vessels in ischemic limbs

March 7th, 2012 1:57 pm

ScienceDaily (Mar. 6, 2012) A new research discovery by a team of Stanford and European scientists offers hope that people with atherosclerotic disease may one day be able to avoid limb amputation related to ischemia. A new research report appearing online in the FASEB Journal suggests that the delivery of genes for two molecules naturally produced by the body, called "PDGF-BB" and "VEGF" may successfully cause the body to grow new blood vessels that can save ischemic limbs.

"We hope that our findings will ultimately develop into a safe and effective therapy for the many patients, suffering from blocked arteries in the limbs, who are currently not adequately treated by surgery or drugs," said Helen M. Blau, Ph.D., a senior researcher involved in the work and Associate Editor of the FASEB Journal from the Baxter Laboratory for Stem Cell Biology at the Institute for Regenerative Medicine and Stem Cell Biology at Stanford. "This could help avoid the devastating consequences of limb amputations for both patients and their families."

To make this discovery, Blau and colleagues, including Andrea Banfi (now at Basel University), introduced the genes for PDGF-BB and VEGF into the muscles of mice, either independently or together. When high doses of VEGF alone were produced, they caused the growth of vascular tumors. When the two factors were produced in unbalanced amounts, tumor growth also occurred. When VEGF and PDGF were delivered in a fixed ratio relative to one another, however, no tumors occurred, and blood flow was restored to ischemic muscle tissue and damage repaired without any toxic effects. To achieve a "balanced" delivery of PDGF-BB and VEGF, scientists placed both genes in a single gene therapy delivery mechanism, called a "vector."

Although the report shows the feasibility of growing robust and safe new blood vessels that restore blood flow to diseased tissues, Blau points out that "there are multiple challenges to correcting peripheral vasculature disease by using proangiogenic gene therapy strategies. Two important challenges are what to deliver and how to get it to where it can have beneficial effects. Clinical success will require both delivering a gene therapy construct that encodes for effective angiogenic factors and ensuring that the sites of delivery are where the construct can have the greatest clinical benefit."

"This ingenious work, based on the latest techniques of molecular biology, tells us that it is possible to reinvigorate parts of our body that can't get enough blood to keep them going," said Gerald Weissmann, M.D., Editor-in-Chief of the FASEB Journal. "The next question is whether this approach will work in humans and exactly how to deliver the new treatment to places that need it the most."

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The above story is reprinted from materials provided by Federation of American Societies for Experimental Biology, via EurekAlert!, a service of AAAS.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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New Research Characterizes Glaucoma as a Neurologic Disorder Rather Than an Eye Disease

March 7th, 2012 1:57 pm

SAN FRANCISCO, CA--(Marketwire -03/06/12)- A new paradigm to explain glaucoma is rapidly emerging, and it is generating brain-based treatment advances that may ultimately vanquish the disease known as the "sneak thief of sight." A review now available in Ophthalmology, the journal of the American Academy of Ophthalmology, reports that some top researchers no longer think of glaucoma solely as an eye disease. Instead, they view it as a neurologic disorder that causes nerve cells in the brain to degenerate and die, similar to what occurs in Alzheimer's and in Parkinson's disease. The review, led by Jeffrey L Goldberg, M.D., Ph.D., assistant professor of ophthalmology at the Bascom Palmer Eye Institute and Interdisciplinary Stem Cell Institute, describes treatment advances that are either being tested in patients or are scheduled to begin clinical trials soon.

Glaucoma is the most common cause of irreversible blindness worldwide. For many years, the prevailing theory was that vision damage in glaucoma patients was caused by abnormally high pressure inside the eye, known as intraocular pressure (IOP). As a result, lowering IOP was the only goal of those who developed surgical techniques and medications to treat glaucoma. Creating tests and instruments to measure and track IOP was crucial to that effort. Today, a patient's IOP is no longer the only measurement an ophthalmologist uses to diagnose glaucoma, although it is still a key part of deciding how to care for the patient. IOP-lowering medications and surgical techniques continue to be effective ways to protect glaucoma patients' eyes and vision. Tracking changes in IOP over time informs the doctor whether the treatment plan is working.

But even when surgery or medication successfully lowers IOP, vision loss continues in some glaucoma patients. Also, some patients find it difficult to use eye drop medications as prescribed by their physicians. These significant shortcomings spurred researchers to look beyond IOP as a cause of glaucoma and focus of treatment.

The new research paradigm focuses on the damage that occurs in a type of nerve cell called retinal ganglion cells (RGCs), which are vital to the ability to see. These cells connect the eye to the brain through the optic nerve.

RGC-targeted glaucoma treatments now in clinical trials include: medications injected into the eye that deliver survival and growth factors to RGCs; medications known to be useful for stroke and Alzheimer's, such as cytidine-5-diphosphocholine; and electrical stimulation of RGCs, delivered via tiny electrodes implanted in contact lenses or other external devices. Human trials of stem cell therapies are in the planning stages.

"As researchers turn their attention to the mechanisms that cause retinal ganglion cells to degenerate and die, they are discovering ways to protect, enhance and even regenerate these vital cells," said Dr. Goldberg. "Understanding how to prevent damage and improve healthy function in these neurons may ultimately lead to sight-saving treatments for glaucoma and other degenerative eye diseases."

If this neurologically-based research succeeds, future glaucoma treatments may not only prevent glaucoma from stealing patients' eyesight, but may actually restore vision. Scientists also hope that their in-depth exploration of RGCs will help them determine what factors, such as genetics, make some people more vulnerable to glaucoma.

Note to media: Contact Media Relations to request full text of the study, arrange interviews with experts, and request images.

About the American Academy of OphthalmologyThe American Academy of Ophthalmology is the world's largest association of eye physicians and surgeons -- Eye M.D.s -- with more than 30,000 members worldwide. Eye health care is provided by the three "O's" -- ophthalmologists, optometrists, and opticians. It is the ophthalmologist, or Eye M.D., who can treat it all: eye diseases, infections and injuries, and perform eye surgery. For more information, visit http://www.aao.org. The Academy's EyeSmart public education program works to educate the public about the importance of eye health and to empower them to preserve their healthy vision, by providing the most trusted and medically accurate information about eye diseases, conditions and injuries. Visit http://www.geteyesmart.org to learn more.

About OphthalmologyOphthalmology, the official journal of the American Academy of Ophthalmology, publishes original, peer-reviewed reports of research in ophthalmology, including basic science investigations and clinical studies. Topics include new diagnostic and surgical techniques, treatment methods, instrument updates, the latest drug findings, results of clinical trials, and research findings. Ophthalmology also publishes major reviews of specific topics by acknowledged authorities.

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New Research Characterizes Glaucoma as a Neurologic Disorder Rather Than an Eye Disease

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Nuvilex Forecasts Vast Partnership Opportunities Using Breakthrough Stem Cell Technology

March 7th, 2012 1:55 pm

SILVER SPRING, Md.--(BUSINESS WIRE)--

Nuvilex, Inc. (OTCQB:NVLX), an emerging biotechnology provider of cell and gene therapy solutions, today pointed out the potential for substantial partnership and licensing opportunities using the companys cell encapsulation technology for applications in stem cell research and medicine. Migration of implanted cells away from the target site and host rejection have been recognized as fundamental challenges faced by the stem cell community regarding their use in therapy, which the companys technology overcomes.

The technology being acquired from associate SG Austria is used to place live stem cells into strong, flexible and permeable capsules. These capsules can then be implanted into animals or humans for specific therapies. Stem cells can then exist at the desired location inside the capsules, prevented from migrating and protected from the immune system that aims to eliminate such foreign cells from the body.

Stem cell therapy is being used by clinicians throughout the world for treating such diverse diseases as spinal cord injury, amyotrophic lateral sclerosis, burns, glioma, multiple myeloma, arthritis, heart disease, stroke, Stargardt's Macular Dystrophy, and age-related macular degeneration, among others, most of which can be found at ClinicalTrials.gov.

Historically, researchers have faced numerous difficulties in succeeding with certain stem cell treatments, because of the problems associated with keeping stem cells alive for significant periods of time, stopping rejection and destruction by the recipients immune system, and keeping stem cells from migrating away from the desired sites. Cells encapsulated in SG Austrias porous beads have been shown to remain alive for long periods of time in humans, surviving intact for at least two years. Once encapsulated, cells are protected from the bodys immune system. Furthermore, encapsulated cells remain within the beads and are unable to migrate to other sites in the body.

In the February 29, 2012 research report, Goldman Small Cap Research stated, The Cell-in-a-Box approach could significantly advance the implementation and utilization of stem cells for a host of debilitating diseases and conditions, making it a uniquely valuable commodity. We believe that by partnering with leading players in the field, Nuvilex could find that companies with deep pockets would be happy to collaborate or license the delivery system and engage in further research which could result in meaningful development and licensing revenue.

Dr. Robert Ryan, Chief Executive Officer of Nuvilex, discussed the value for licensing the companys stem cell therapy, adding, By overcoming traditional barriers to effective stem cell therapy, namely viability, migration, and host rejection, we believe these new advances in medical science utilizing stem cells and encapsulation will enable us to take quantum leaps forward now and in the future. As a result of challenges SG Austria has overcome, new advances will be surprisingly close at hand and are part of the driving force behind our desire to work with a number of companies in this endeavor. Our primary goal has been and remains to use our technology to bring life changing treatments to patients on an expedited basis.

About Nuvilex

Nuvilex, Inc. (OTCQB:NVLX) is an emerging international biotechnology provider of clinically useful therapeutic live encapsulated cells and services for encapsulating live cells for the research and medical communities. Through our effort, all aspects of our corporate activities alone, and especially in concert with SG Austria, are rapidly moving toward completion, including closing our agreement. One of our planned offerings will include cancer treatments using the companys industry-leading live-cell encapsulation technology.

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Influencing stem cell fate: New screening method helps scientists identify key information rapidly

March 7th, 2012 10:39 am

ScienceDaily (Mar. 6, 2012) Northwestern University scientists have developed a powerful analytical method that they have used to direct stem cell differentiation. Out of millions of possibilities, they rapidly identified the chemical and physical structures that can cue stem cells to become osteocytes, cells found in mature bone.

Researchers can use the method, called nanocombinatorics, to build enormous libraries of physical structures varying in size from a few nanometers to many micrometers for addressing problems within and outside biology.

Those in the fields of chemistry, materials engineering and nanotechnology could use this invaluable tool to assess which chemical and physical structures -- including size, shape and composition -- work best for a desired process or function.

Nanocombinatorics holds promise for screening catalysts for energy conversion, understanding properties conferred by nanostructures, identifying active molecules for drug discovery or even optimizing materials for tissue regeneration, among other applications.

Details of the method and proof of concept is published in the Proceedings of the National Academy of Sciences.

"With further development, researchers might be able to use this approach to prepare cells of any lineage on command," said Chad A. Mirkin, who led the work. "Insight into such a process is important for understanding cancer development and for developing novel cancer treatment methodologies."

Mirkin is the George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences and professor of medicine, chemical and biological engineering, biomedical engineering and materials science and engineering. He also is the director of Northwestern's International Institute for Nanotechnology (IIN).

The new analytical method utilizes a technique invented at Northwestern called polymer pen lithography, where basically a rubber stamp having as many as 11 million sharp pyramids is mounted on a transparent glass backing and precisely controlled by an atomic force microscope to generate desired patterns on a surface. Each pyramid -- a polymeric pen -- is coated with molecules for a particular purpose.

In this work, the researchers used molecules that bind proteins found in the natural cell environment, such as fibronectin, which could then be attached onto a substrate in various patterns. (Fibronectin is a protein that mediates cell adhesion.) The team rapidly prepared millions of textured features over a large area, which they call a library. The library consisted of approximately 10,000 fibronectin patterns having as many as 25 million features ranging in size from a couple hundred nanometers to several micrometers.

To make these surfaces, they intentionally tilt the stamp and its array of pens as the stamp is brought down onto the substrate, each pen delivering a spot of molecules that could then bind fibronectin. The tilt results in different amounts of pressure on the polymeric pens, which dictates the feature size of each spot. Because the pressure varies across a broad range, so does the feature size.

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