Navigation Links
Schepens Scientists Identify Key to Integrating Transplanted Nerve,Cells Into Injured Tissue

Discovery promises to make retina, spinal cord and other central nervous system transplants possible

BOSTON, April 26, 2007 /PRNewswire/ -- Scientists at the Schepens Eye Research Institute, an affiliate of Harvard Medical School, have identified a key mechanism for successfully transplanting tissue into the adult central nervous system. The study found that a molecule known as MMP-2 (which is induced by stem cells) has the ability to break down barriers on the outer surface of a damaged retina and allow healthy donor cells to integrate and wire themselves into remaining recipient tissue. The finding, reported in the current issue (April 25, 2007) of the Journal of Neuroscience, holds great promise not only for patients with retinal disease, but also for those suffering from spinal cord injuries and neurodegenerative disorders such as Parkinson's and Alzheimer's Diseases.

"This is a very significant finding," says Dr. Michael Young, associate scientist at the Schepens Eye Research Institute and principal investigator of the study. "We believe that it will ultimately make retinal transplantation and restoration of vision a possibility." He adds that transplantation of donor photoreceptors (in whole retina transplants) may prove to be more beneficial than transplanting stem cells alone, as these retinal transplants contain a complete organized supply of cells necessary for proper vision.

The regenerative capacity of central nervous system tissue in adult mammals, including human begins, is extremely limited. This is partly due to the formation of barriers, known as "glial" scars, which are triggered by the body to protect the injured retina or other nerve tissue from further damage. This dense scar tissue throws up a blockade to foreign cells, including transplants meant to heal and regenerate. This is what has made previous attempts to transplant whole donor retinas so difficult, according to Young .

On the other hand, in recent years, stem cells have been shown to overcome these physical barriers, easily penetrating the scar and integrating into the injured tissue.

For instance, in studies published several years ago, Young and his colleagues demonstrated this special stem-cell talent in damaged mouse retinas. In those studies cells injected into injured retinas quickly integrated into the existing retinal tissue.

Intrigued by this phenomenon, Young and his team believed that if they could identify and harness the key molecules used by stem cells to gain access into the injured retina, they could potentially improve the success of non- stem cell transplants. Based on this idea, the team conducted a series of experiments.

In their initial experiments, the team compared the chemicals that were generated when stem cells were injected into damaged retinas and those produced when they attempted to transplant whole retina tissue into the eyes of mice with degenerated retinas. They found-in the stem cell injected retinas-an increase in the amount of and the level of activity of the molecule MMP-2 in host tissue. They concluded that this molecule dissolved the scar on the outer surface of the retina. There was no increase in MMP-2 when they attempted whole-retina transplants.

The team went on to transplant a layer of stem cells between the degenerating mice retinas and healthy donor tissue (whole retina). They found that MMP-2 induced removal of the scar barrier and allowed healthy donor cells (of the whole retina) to make new connections with the damaged retinas in the mice.

"These are very powerful results," says Young. "We are convinced that the increase of this molecule is a major key to creating a permissive environment for central nervous system regeneration."

The team is now investigating therapeutic approaches that would eliminate the need for stem cells. This would involve the use of just the MMP-2 molecule, w hich is already available in the pharmaceutical market, to foster a receptive transplant environment in the eye, and, in other CNS tissues.

Other scientists involved in the study include: Yiqin Zhang, Henry J. Klassen, Budd A. Tucker, and Maria-Thereza R. Perez.

Schepens Eye Research Institute is an affiliate of Harvard Medical School and the largest independent eye research institute in the world.

CONTACT: Patti Jacobs of Schepens Eye Research Institute, +1-617-872-0364, pjacobs12@comcast.net

Web site: http://www.schepens.org//

Terms and conditions of use apply
Copyright © 2007 PR Newswire Association LLC. All rights reserved.
A United Business Media Company


'"/>




Related medicine technology :

1. Rosetta Genomics and Weizmann Institute Scientists Identify Role of microRNA in Cancer Suppression
2. Karmanos Physician-Scientists Examine Racial Disparities in Patients with Gynecologic Cancer
3. Scientists Implicate Gene in Vitiligo and Other Autoimmune Diseases
4. The Sturdier Sex?: Study by Pittsburgh Scientists Finds Female Stem Cells Work Better
5. Alnylam and Stanford University Scientists Discover New Role for microRNAs (miRNAs) in T Cell Biology and Immunity
6. Scottish Scientists Test ‘Secret Weapon’ Against Tumours
7. NIEHS Researchers Identify Enzyme Critical in DNA Replication
8. Researchers Discover Method for Identifying How Cancer Evades the Immune System
9. Researchers Identify New Genetic Risk Factors for Type 2 Diabetes
10. Preclinical Studies Identify Novel Approach for Enhancing the Anticancer Activity of Introgens INGN 241
11. Researchers Identify Intracellular Pathway of Alfacells Onconase
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/5/2016)... , Feb. 5, 2016  Henry Schein, Inc. (NASDAQ: ... products and services to office-based dental, animal health and ... an agreement to acquire a majority ownership interest in ... equipment in Brazil . ... Blumenau, Brazil, Dental Cremer is the dental distribution business of ...
(Date:2/5/2016)... 4, 2016 France , ... , UK, and Israel ). It includes a 10-year ... 3 GD, segmented by age and sex in these markets. GD epidemiology ... Report is in-depth, high quality, transparent and market-driven, providing expert analysis of ... Germany , Italy , ...
(Date:2/4/2016)... For hospitals considering enrollment in the Federal ... the program, the Health Resources and Services Administration,s (HRSA) ... Mega-Guidance , could have significant impact on plans and ... 2016. Essential Insights , Daniel Neal, ... the Mega-Guidance,s key proposed changes, including a new requirement ...
Breaking Medicine Technology:
(Date:2/5/2016)... & Salt Lake City, UT (PRWEB) , ... February 05, 2016 ... ... of Activz Whole-Food Nutrition , announced that the much-anticipated feature with author Jahnavi ... New Really Cool Humans Amateur TV Network. , Each week, on his weekly Whole-Food ...
(Date:2/5/2016)... (PRWEB) , ... February 05, 2016 , ... Looking for ... may be at the tips of your toes. Foot massage, whether administered by a ... pure comfort and relaxation. The American Board of Multiple Specialties in Podiatry ...
(Date:2/5/2016)... ... February 05, 2016 , ... In ... across the country gathered at the La Valencia Hotel in San Diego, California ... Chicago was named the year’s most outstanding franchise, walking away with the coveted ...
(Date:2/5/2016)... ... February 05, 2016 , ... Pivot Point Consulting, a leading ... Software & Services for HIT Implementation Support & Staffing report with an outstanding ... performance by healthcare executives, managers and clinicians representing over 4,500 hospitals and 2,500 ...
(Date:2/5/2016)... , ... February 05, 2016 , ... Colorize ... on one drop zone to the next using Colorize's dynamic moving camera. Colorize is ... This package includes a 3D slideshow environment with 1 to 5 focus points per ...
Breaking Medicine News(10 mins):