CHARACTERIZATION OF ENDOTRYPANUM PARASITES USING SPECIFIC MONOCLONAL-ANTIBODIES

A large number of Endotrypanum stocks (representing an heterogeneous p opulation of strains) have been screened against a panel of monoclonal antibodies (MAbs) derived for selected species of Endotrypanum or Lei shmania, to see whether this approach could be used to group/different iate further among these parasites. Using different immunological assa y systems, MAbs considered specific for the genus Endotrypanum (E-24, CXXX-3G5-F12) or strain M6159 of E. schaudinni (E-2, CXIV-3C7-F5) reac ted variably according to the test used but in the ELISA or immunofluo rescence assay both reacted with all the strains tested. Analyses usin g these MAbs showed antigenic diversity occurring among the Endotrypan um strains, but no qualitative or quantitative reactivity pattern coul d be consistently related to parasite origin (i.e., host species invol ved) or geographic area of isolation. Western blot analyses of the par asites showed that these MAbs recognized multiple components. Differen ces existed either in the epitope density or molecular forms associate d with the antigenic determinants and therefore allowed the assignment of the strains to specific antigenic groups. Using immunofluorescence or ELISA assay, clone E-24 produced reaction with L. equatorensis (wh ich is a parasite of sloth and rodent), but not with other trypanosoma tids examined. Interestingly, the latter parasite and the Endotrypanum strains crossreacted with a number of MAbs that were produced against members of the L. major-L. tropica complex.