Retinal Reparation

Stem cells exist naturally in the retina. However, if the retina is damaged, the retinal stem cells cease to function. Researchers have removed stem cells from the retina and cultivated them in petri dishes. Through stem cell research, scientists are coming closer to finding a cure for some forms of blindness.

Macular Degeneration

Macular degeneration is the leading cause of vision loss. In this eye disease, the central portion of the retina, known as the macula, detiorates. Recently, in 2012, eighteen patients with macular degeneration participated in a study. The patients received transplants of 50,000 to 150,000 retinal pigment epithelial (RPE) cells that were developed from human embryonic stem cells. Ten of the eighteen patients reported significant vision improvement. Scientists were concerned that the stem cell transplant would cause cancer if the stem cells developed into unwanted cell types. Furthermore, they feared body would reject the transplants

Two years later, patients showed no sign of cancer growth nor rejection. Dr. Steven Schwartz, leader of the study, says: "Our results suggest the safety and promise of [human embryonic stem cells] to alter progressive vision loss in people with degenerative diseases and mark an exciting step towards using [these] stem cells as a safe source of cells for the treatment of various medical disorders requiring tissue repair or replacement." Though still in the clinical trial phase, this therapy may become a commonly used procedure to treat macular degeneration in future years.

Glaucoma

Glaucoma is a series of eye conditions in which the pressure in the eye is abnormally high. The high pressure damages the optic nerve, which is formed with retinal ganglion cells. These conditions lead to blindness. Ophthalmologists can slow the progression of glaucoma by lowering the pressure in the eye, if the condition is detected early. However, ten percent of patients who receive that treatment still experience vision loss.

Researchers are currently investigating the use of mesenchymal stem cells (MSCs), which are found in the bone marrow, in regenerating retinal ganglion cells of the optic nerve. MSCs are multipotent stem cells that can differentiate into neurons. These stem cells are favorable because they require no genetic modification and will not be rejected by the body. Studies have shown that MSC transplant decrease retinal ganglion cell loss. Clinical trials that involve using MSCs to treat glaucoma have begun in Florida and will continue into 2017.