Borrelia burgdorferi surface proteins
By Linda on Feb 22, 2011 in Infections
Excerpt:
Antibiotic-refractory Lyme arthritis may result from Borrelia
burgdorferi-induced autoimmunity in affected joints. Such patients usually
have certain HLA-DRB1 molecules that bind an epitope of B. burgdorferi
outer-surface protein A (OspA), and cellular and humoral immune responses to
OspA are greater in patients with antibiotic-refractory arthritis than in
those with antibiotic-responsive arthritis. Recent work in a mouse model
suggests that, during B. burgdorferi infection, OspA in genetically
susceptible individuals stimulates a particularly strong T(H)1 response,
which may be one of several factors that can help set the stage for a
putative autoimmune response in affected joints. However, vaccination with
OspA did not induce arthritis in this mouse model, and case and control
comparisons in human vaccine trials did not show an increased frequency of
arthritis among OspA-vaccinated individuals.
Thus, a vaccine-induced immune response to OspA does not replicate the
sequence of events needed in the natural infection to induce
antibiotic-refractory Lyme arthritis.
