Own stem cells will restore the cornea
Researchers at the University of Pittsburgh, working under the guidance of Professor James L. Funderburg, have developed a method to prevent the formation of scars on the cornea of the eye using the patient's own stem cells.
Infections and injuries, including chemical and thermal burns, of the cornea of the eye often lead to the formation of scars that obscure vision or, in particularly severe cases, lead to blindness. Traditionally, donor cornea transplantation is used to eliminate this problem, but this procedure is complicated by a shortage of donor material. Moreover, quite often transplants do not take root or are rejected by the patient's immune system.
The authors propose an alternative approach, which consists in applying the patient's own (autologous) stem cells to the corneal injury zone. The method of isolating these cells, developed by Dr. Sayan Basu from the Prasad Eye Research Institute in Hyderabad, India, involves removing a tiny fragment of tissue from the surface of the eye in the limbic region – the region between the cornea and sclera. This procedure causes only minor discomfort and does not interfere with vision. Moreover, the use of the patient's own cells eliminates the likelihood of developing an immunological rejection reaction and increases the likelihood of successful engraftment.
As part of the study, the authors isolated mesenchymal stem cells from biopsy material extracted from the eyes of cadaveric donors. The cells were multiplied in the laboratory and a number of experiments were conducted to confirm their belonging to corneal stem cells.
After that, human stem cells with the help of fibrin gel were applied to the damage to the cornea of the eye of mice. (Fibrin is a protein in the blood involved in the formation of blood clots and used in surgery as an adhesive material.) Animal observation showed that within 4 weeks after the procedure, the cornea of the eye was completely restored and had no signs of scarring. Vision-blurring scars formed on the damaged cornea of the control group mice.
According to the authors, even at the microscopic level, they could not find differences between the intact cornea and the tissue regenerated with the help of stem cells. They also noted that the damage to the cornea was completely restored, and not only in the places of direct application of stem cells. This indicates the ability of the latter not only to replace damaged tissue, but also to produce growth factors that stimulate regeneration.
The obtained results formed the basis of a small pilot clinical trial, in which several patients at the Hyderabad Clinic will soon undergo therapy with their own stem cells.
Article by Sayan Basu et al. Human limbal biopsy-derived stromal stem cells prevent corneal scarring is published in the journal Science Translational Medicine.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru According to the University of Pittsburgh Schools of the Health Sciences: Patient's Own Stem Cells Could Clear a Cloudy Cornea, Pitt Team Says.
15.12.2014