In some patients infected with the spirochete Borrelia burgdorferi, Lyme arthritis develops as a late sequela. In about 10 percent of these patients, the arthritis is resistant to antibiotic therapy and becomes chronic. There is usually no detectable spirochetal DNA in the affected joints. Human leukocyte-function–associated antigen 1 (LFA-1, CD11a/CD18, or integrin αLβ2) has been proposed as an autoantigen in these patients because it contains a peptide sequence that is homologous to one in the outer-surface protein A (OspA) of B. burgdorferi. 47 Synovial-fluid T cells from some patients with chronic Lyme arthritis, but not from patients with other forms of arthritis, react in vitro with the peptide, as well as with the intact LFA-1 and OspA proteins. In patients with the appropriate genetic background associated with Lyme arthritis, priming by B. burgdorferi infection is apparently still required for the development of an autoimmune response to LFA-1. The mechanistic link between this autoreactivity against LFA-1 and the synovitis of B. burgdorferi infection awaits further definition. nejm.org/doi/full/10.1056/NEJM199912303412707
Posted on: Tue, 30 Jul 2013 10:15:41 +0000
Trending Topics
Recently Viewed Topics
© 2015