Antibody to 65-kD stress protein (HSP65) of Mycobacterium leprae in various inflammatory skin diseases. A preliminary report.

Cells from prokaryotes and eukaryotes exposed to environmental changes produce a series of highly homologous proteins called stress proteins, or heat shock proteins (HSPs). Recent investigators suggested that the reaction to the shared antigenic epitope between HSPs may link infections with induction of autoimmune processes. In the present study, antibody level to HSP with 65 kDa (HSP65) of Mycobacterium leprae was investigated with enzyme-linked immunosorbent assay (ELISA) in various skin diseases. Comparing to normal group (n = 9) including patients with nevus cell nevus showing 0.097 +/- 0.039 (mean +/- SD) in anti-HSP65 IgG level (OD492), 20 patients with palmoplantar pustulosis (PPP) and 22 with psoriasis demonstrated elevated (0.170 +/- 0.079, 0.111 +/- 0.053, respectively) level. Among them patients judged as focal infection-related PPP or psoriasis showed significantly higher level of anti-HSP65 (p < 0.01) than those without focal infection. Anaphylactoid purpura (0.125 +/- 0.085, n = 5), Behcet disease (0.178 +/- 0.045), atopic dermatitis (0.218 +/- 0.096, n = 13), urticaria (0.185 +/- 0.079, n = 30), and herpes zoster (0.193 +/- 0.092, n = 13) showed likewise elevated anti-HSP65 antibody. Similar tendency was found in anti-HSP65 IgM level but not in anti-HSP65 IgA. Western blotting confirmed specific immunoreaction bands to HSP65 in blood samples with high titer. Immunomodulation by stress proteins of bacterial or host cells is assumed in pathophysiology of inflammatory skin disorders, especially in relation to focal bacterial infection as observed in cases with PPP and psoriasis.