How cells alert the immune system can drive autoimmune disease.

Cells alert the immune system that they are infected by holding small protein fragments of the infectious organism on their surface. The immune system destroys the cell after binding to the fragment and the protein holding it, known as HLA. Humans have a wide variety of HLAs, several of which have been associated with autoimmune diseases, ranging from type 1 diabetes to multiple sclerosis and chronic beryllium disease. Research teams at National Jewish Health are probing the molecular details of these HLAs to understand how their presentation of protein fragments could misdirect the immune system toward autoimmune disease. Findings by John Kappler, PhD; Shaodong Dai, PhD; and others have produced critical insights into type 1 diabetes and chronic beryllium disease, which suggest new treatments and possible prevention.