Onchocerca volvulus: characterization of monoclonal antibodies reactive with surface components of third-stage larvae.

Five murine monoclonal antibodies (Mab's) have been produced which are reactive with the surface of the third-stage larvae (L3) of Onchocerca volvulus. These were produced from a fusion performed after intrasplenic injection of 10 live O. volvulus L3. Hybridomas were first screened by Elisa using a PBS extract of O. volvulus female adult worms. Elisa negative wells were screened by IFA on whole formalin-fixed L3. Five Mab's were isolated which were reactive with the surface of L3, all were found to be of the IgM isotype. All five Mab's were cross-reactive with the surface of O. lienalis L3, but not with the L3 of Brugia malayi, B. pahangi, Dirofilaria immitis, or Acanthocheilonema viteae. One of the Mab's, OV3-9, reacted with an antigen common to many species of helminths. The other four were genus specific reacting only with O. volvulus and O. lienalis. All 5 Mab's reacted with L2 of O. volvulus, but not with the L4 by IFA on whole fixed larvae. Only Mab's OV3-8 and OV3-9 reacted with cryosections of adult O. volvulus by IFA indicating that the other 3 Mab's are specific for the surface of L2/L3 of the genus Onchocerca. None of the Mab's reacted with detergent dissociated L3 proteins in Western Blot analysis. The ability of L3 to bind the Mab's was abolished by incubating larvae in either proteinase K or trypsin but was unaffected by incubation of larvae in detergents, or by treatment with periodate, indicating the proteinaceous nature of the Mab specific epitopes. Anti-phosphorylcholine Mab (Gib-13) did not react with the surface of L3.(ABSTRACT TRUNCATED AT 250 WORDS)