下面一段是美国Stemedica公司和俄罗斯一个医院合作的项目，动物实验中取得了非常好的效果，现在医院在做人体实验，论坛上也有文章介绍。
Stemedica (San Diego, CA)
I first learned about Stemedica’s involvement in the use of stem cells to treat retinal disease in January 2007, upon seeing a news release announcing the company’s collaboration with Lumenis to use the latter’s SRT laser to “wound” the retina to be followed by injection of stem cells to repair the damage caused by the laser impact. The work was to be undertaken at the Fyodorov Eye Institute in Moscow.
Unfortunately, that collaboration fell through, but Stemedica continued to study the use of stem cells (and lasers) in treating retinal diseases at the Fyodorov Eye Institute.
In July 2009, another news release announced that Stemedica had had a breakthrough in the use of human stem cells and stem cell factors for the potential treatment of retina and retinal pigmented epithelium degeneration, including diseases such as Retinitis Pigmentosa.
According to one of the study's Principle Investigators, Dr. Paul Tornambe, "The results from this pre-clinical experiment are exciting. It allows researchers and clinicians to push the envelope in the quest to use stem cells to modulate diseases like Retinitis Pigmentosa." There is currently no medical treatment that can completely cure Retinitis Pigmentosa - an eye disease that affects approximately 1,500,000 people on a worldwide basis each year.
The 18 month pre-clinical study was implemented at the Fyodorov Eye Institute using Stemedica's proprietary multiple cell technology. Three different types of human stem cells (hSC) were used in the study - retinal pigment epithelium (RPE), neural (NSC) and cilliary body (CB) - all obtained from human donor tissue. Various cells were injected into rats with hereditary pigmented degradation of retina. One eye of each participating rat served the treatment eye and the other eye served as the control eye. Healthy non-dystrophic and non-treated (normally dystrophic) animals were also used as independent control groups. Electroretinography (ERG) and immunohistochemical (ICH) analysis was performed on both eyes.
The research team compared the efficacy of each of the three cell types. A summary of the results yielded the following observations and discoveries:
1. The study showed a statistically significant gain (77%) in the treated eye (with RPE cells) over the control eye of the same animal. However, both the treated eye and the control eye were approximately 10 times more active (response to ERG) compared to non-treated (normally dystrophic) control animal.
2. The RPE and NSC cells were effective in preserving the thickness of the outer nuclei layer of the retina.
3. A contra lateral effect was observed between the test and control eyes. As a result, both eyes exhibited significant improvement. It is believed that the positive outcome in the control eye was achieved through the systemic release of cytokines; growth and other important factors; peptides; and, molecules from stem cells transplanted into the treated eye. This phenomenon is referred to by Stemedica as "The Factor Release Effect" and branded by the company as StemedicaFRET. These factors, circulating in the blood flow, effect and mobilize endogenous stem cells. Stemedica believes improvement in the contra lateral eye is a 'Factor Release Effect' rather than a Sympathetic Ophthalmic effect which is very rare.
Then, at the Laser Florence 2009 Meeting, Drs. Alexei Lukashev and Eugene Baranov (Stemedica); Natalia Gavrilova (Fyodorov Eye Institute); Irina Saburina and Alexander Revischin (Russian Academy of Medical Science); and Paul Tornambed (Retina Specialists, San Diego) presented a paper, “Combination of a Laser and Stem Cells in Posterior Eye Ophthalmology”, that described the use of the combination of laser and stem cells in treating the retina of a rabbit model.
An argon laser at 514nm and a dye laser at 577nm were used to provide a controlled damage on the rabbit retina. Two type of human progenitor stem cells(hPSC) were tested: Mesenchymal and Neural. Four cell delivery methods were compared: Retrobulbar, Introvitreous, Subconjuctival and Suprachoroidal injections. Electroretinography(ERG) was used as a diagnostics of retina functionality. Selective immunohystochemical analysis was performed to assess cells migration and viability.
Controlled laser damage on retina provided a strong attracting signal for the stem cells. The team concluded that, application of laser light enhances results of stem cells injection in the posterior eye and may have benefits for treatment of different types of retinopathy and macular degeneration.
This paper was published by AIP Conf. Proc. -- May 31, 2010 -- Volume 1226, pp. 82-90
According to the company’s website, both clinical and pre-clinical work is currently underwayat the Fyodorov Eye Institute in using stem cells (and lasers?) In treating diabetic retinopathy, macular degeneration, retinitis pigmentosa, and in the treatment of glaucoma.
Unanswered questions Posed to the company and awaiting answers.)
What is the current status of these clinical studies? Are they being conducted in human eyes?
And, exactly what is being done in the glaucoma work? This is the second time I have heard of stem cells being applied to glaucoma. Can you provide some further explanation? |
