Diagnostic M_r31 000Schistosoma mansoniproteins: requirement of infection, but not immunization, and use of the “miniblot” technique for the production of monoclonal antibodies

Abstract

Antibodies directed against diagnostic Mr 31 000 polypeptide(s) of adult Schistosoma mansoni were already formed in mice during prepatency. In contrast, repeated immunization of mice with homogenates of adult schistosomes failed to elicit antibodies detectable in immunoblots in the Mr 31 000 region. Therefore, spleen cells of infected mice were used to produce hybridoma lines. The “miniblot technique” was developed in order to detect in hybridoma supernatants antibodies against schistosome Mr 31 000 components. Electrophoretically separated total S. mansoni proteins were transferred onto nitrocellulose, and the position of the Mr 31 000 components was determined with polyclonal antisera and immunoblotting. Pieces of about 3 square mm of nitrocellulose bearing the diagnostic proteins were incubated with about 100 μ1 of hybridoma supernatant in microtitre plates and subsequently probed with peroxidase-conjugated antibody to mouse IgG. This screening technique identified hybridomas secreting antibody to the relevant S. mansoni antigens. It is applicable to other defined parasit antigens, which are, however, not available in biochemically purified form. The monoclonal antibodies produced against the proteins with diagnostic potential reacted with antigens localized in the schistosome gut.

Variations in immunofluorescent antibody response against Trichobilharzia and Schistosoma antigens in compatible and incompatible hosts

“…In S. mansoni, the anti-gut 31/32 kDa antibodies were neither observed following the vaccination of mice with irradiated cercariae (Ruppel et al 1985) nor after immunisation with a schistosome homogenate (Ruppel et al 1987a). As we have observed, the incomplete development of T. regenti and T. szidati in mammals may preclude anti-gut antibody formation in a nonspecific host.…”

Analysis of Schistosoma japonicum antigens useful for serodiagnosis employing sera of infected mice by immunoblotting.

“…Second, antibodies to them are constantly detected in all of the infected sera despite the appearance of antibodies to the other components of the worms varies. Third, the component of S. japonicum was not detected by sera from immunized mice as was observed with component of S. mansoni (Ruppel et al, 1987).…”

Hybridoma cell agglutination as a novel test to detect circulating antigen of Schistosoma japonicum

“…The hybridoma cell line secreting H226 originated from a fusion of cells of a myeloma line (P3‐X63‐Ag8.653) with spleen cells from a S. mansoni ‐infected Balb/c mouse (Ruppel et al . 1987).…”