A team from University College London and King’s College London reduced the effects of uveitis in mice using cancer drugs, representing a potential new avenue for treating autoimmune disease.
Uveitis is an incurable autoimmune disease in which the immune system attacks the uvea, the pigmented layer of the eye. Current treatments focus on tamping down on inflammation, but can cause glaucoma or cataracts to form. The team decided to test out the cancer drugs after finding that P-TEFb, a genetic "key" involved in cancer growth, also plays a role in autoimmune disease.
Immune cells need P-TEFb to become T helper cells, which help to fight off infections in healthy people. But in people with autoimmune disease, these T cells attack and damage healthy tissue.
The team dosed mice with drugs that inhibit P-TEFb and then induced uveitis. They saw that the condition was less severe in mice that had been given the drugs.
“Blocking this genetic key, called P-TEFb, prevents the immune system from mobilising such an aggressive response,” said Richard Jenner of the UCL Cancer Institute in the statement. “P-TEFb is important for a lot of cellular processes, and drives uncontrolled growth in cancer cells. A variety of drugs that target this pathway are currently undergoing trials for a range of cancers, and we hope to adapt these to target autoimmune conditions in future.”
The team is looking into the potential of using the drugs in other autoinflammatory conditions, such as inflammatory bowel disease, said co-senior author Graham Lord of King’s College London. "If we can show that by targeting this specific pathway, we can cure other autoimmune diseases, then the potential for this treatment to translate through to significant patient impact is very high,” he said.
But while the team believes this class of drugs could be applicable in autoimmune diseases beyond uveitis, Jenner cautioned that the approach needs to be refined. “The drugs that we used in this study would be too toxic for long term use in the bloodstream, so we are now hoping to test more localised approaches such as eye drops to treat uveitis,” he said.