Serological differentiation of microsporidia with special reference Trachipleistophora hominis

Myositis is a common clinical syndrome in advanced stages of AIDS. Trochipl eistophora hominis (phylum Microspora) has been detected in several cases o f painful, immobilising myositis in AIDS patients. Enzyme linked immunosorb ent assays (ELISAs) and Western blotting of protein profiles separated by S DS PAGE were used to determine whether this species could be detected and d ifferentiated by serology. Sixteen microsporidia, including several species known to infect man and species infecting fish, crustaceans and a mosquito , were used as antigen. Each species had a unique profile of SDS PAGE-separ ated proteins. In Western blots, mouse antiserum, raised to T. hominis and selected for its high ELISA specificity, bound to antigens ranging from les s than 25 kDa to greater than 250 kDa with major bands at 39-44 kDa and 98- 150 kDa on T. hominis protein profiles. The serum also recognised some high molecular weight antigens in the profiles of Vaviaia culicis, Heterosporis anguillarum, and three species of Pleistophora but none in the remaining g enera examined. ii was concluded that ELISA and Western blotting could be u sed to detect and differentiate T. hominis in muscle biopsy tissue from pat ients with myositis. However, sera from T. hominis-infected patients in the terminal stages of AIDS would not be useful for detection of infections be cause of a sharp decline in antibody level.