Schistosoma: a 200-kDa chemotherapeutic target antigen is differentially localized in African vs Oriental species.
A 200-kDa protein of the African schistosome Schistosoma mansoni has been identified as a target of antibodies that act in synergy with praziquantel. Treatment of worms with praziquantel exposes selective epitopes of the 200-kDa protein on the surface of S. mansoni and transfer of a monoclonal antibody recognizing the 200-kDa protein at the time of drug treatment restores the effectiveness of praziquantel against infections in B-cell-depleted mice. In the present study, a cross-reactive 200-kDa protein was identified in the three major schistosome species by Western blot analysis using a polyclonal rabbit antiserum recognizing the 200-kDa protein from S. mansoni. Surprisingly, three monoclonal antibodies generated against immunogenic epitopes of the 200-kDa protein did not recognize the 200-kDa protein of the Oriental species Schistosoma japonicum, although they did recognize the 200-kDa protein of another African species Schistosoma haematobium. Furthermore, in the case of S. japonicum, treatment with praziquantel did not expose the 200-kDa protein on the worm surface. Even acetone treatment, which makes surface epitopes more accessible, did not expose the 200-kDa protein on the surface of S. japonicum. In contrast, the 200-kDa protein of S. haematobium was exposed following treatment with praziquantel, and acetone fixation resulted in significantly increased reactivity of the rabbit alpha 200-kDa antiserum with the surface of both S. mansoni and S. haematobium worms.
Tanaka
T M
TM
Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Skubitz
A P
AP
Strand
M
M
D000818:Animals; D000909:Antibodies, Helminth / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D000947:Antigens, Helminth / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D015153:Blotting, Western; D003429:Cross Reactions; D000939:Epitopes / Q000032:analysis / Q000737:chemistry / Q000276:immunology; D005455:Fluorescent Antibody Technique; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D008970:Molecular Weight; D011223:Praziquantel / Q000494:pharmacology; D012548:Schistosoma haematobium / Q000187:drug effects / Q000276:immunology*; D012549:Schistosoma japonicum / Q000187:drug effects / Q000276:immunology*; D012550:Schistosoma mansoni / Q000187:drug effects / Q000276:immunology*
D000909:Antibodies, Helminth; D000911:Antibodies, Monoclonal; D000947:Antigens, Helminth; D000939:Epitopes; D007106:Immune Sera; D011223:Praziquantel