Diabetic retinopathy is a common side effect in Type 1 and Type 2 diabetes--it's seen in around 80 percent of people who have had diabetes for 10 years or more. It can lead to blurred vision and blindness as new blood vessels grow across the back of the eye. Biomarkers for this new growth could help with earlier diagnosis, or lead to new treatments, and a team of Italian researchers have found a rare cell that might be a pointer.
Endothelial progenitor cells (EPCs) are the cells that form the lining of blood vessels. When blood vessels are damaged, or new blood vessels are needed, these rare cells respond to signals and enter the circulation to carry out repairs. The researchers looked at people with Type 1 diabetes and found changes in one type of EPCs, known as colony-forming unit (CFU)-Hill cells.
When the cells were cultivated in vitro, the CFU-Hill cells from people with long-term Type 1 diabetes and retinopathy formed more colonies than normal, and showed lower levels of the molecules that help the cells home in on sites of vascular injury. The cells from people with Type 1 diabetes and no retinopathy, despite having had diabetes for a long period, didn't show any of these changes. A number of people with no signs of clinical retinopathy and short-term diabetes did show changes to their CFU-Hill cells, which may suggest a risk of retinopathy, but the research is too early to confirm this.
Diabetic retinopathy is treatable (but not curable) unless the damage has gone too far, but the symptoms are inconvenient and can be distressing. Tight management of diabetes and other risk factors can reduce the incidence of diabetic retinopathy, and the earlier it is diagnosed, the more effective the treatment is. This is very early-stage research, but finding these cells in the circulation could form the basis of a blood test that supports eye checks, and even points out changes before they become visible in an eye examination or cause symptoms in the patient. They could also be a target to develop treatment.