The retina contains the blood-retinal barrier, which regulates the flow of oxygen, nutrients, and drugs. This barrier is formed by endothelial cells of blood vessels, along with pericytes and astrocytes. Due to their specificity, these cells are virtually impossible to obtain in sufficient quantities, limiting research and the development of new treatments.
To address this issue, the researchers used induced pluripotent stem cells. They were first converted into normal vascular endothelial cells and then, using a combination of growth factors, reprogrammed into endothelial cells specific to retinal vessels.
The resulting cells were tested in preclinical experiments, including mouse models. Under laboratory conditions, they formed vascular networks and structures similar to those that arise in the body. The scientists then exposed the cultured tissue to low oxygen levels and high glucose concentrations. These conditions are characteristic of diabetic retinopathy and led to the destruction of the vascular barrier, similar to what occurs in patients. This demonstrated that the new model is capable of reproducing key disease mechanisms.
When administered to mice before significant vision loss occurred, the cells successfully integrated into the existing vasculature, promoted the formation of mature blood vessels, and restored tissue barrier function.
Currently, retinal endothelial cells are obtained directly from human tissue, making their production expensive and availability limited. This new approach allows for a virtually unlimited supply of cells at a lower cost and with more consistent characteristics.
Previously, other scientists developed technology to generate a virtually unlimited supply of immune system progenitor cells that can be genetically modified to fight cancer and other diseases.
