PRODUCTION AND CHARACTERIZATION OF MONOCLONAL-ANTIBODIES AGAINST THE MAJOR CYSTEINE PROTEINASE OF TRYPANOSOMA-CRUZI

In the present study we describe the production and characterization o f a panel of monoclonal antibodies (MoAbs) directed against cruzipain (Crz), the major cysteine proteinase from Trypanosoma cruzi. The five MoAbs, BD6, BF2, CG2, CH8, and DC10 were analysed with respect to affi nity and specificity. None of the MoAbs cross-reacted with papain, whi ch has regions of high homology with Crz. Treatment of the antigen wit h periodate did not affect the binding of the MoAbs, suggesting that t hey bind to the polypeptide moiety of Crz. CH8 recognized a continuous epitope located at the C-terminal extension of the proteinase that ap peared to be highly immunogenic. Although the rest of the MoAbs recogn ized epitopes located in the catalytic domain, the enzymatic activity of Crz was not impaired by the binding of the MoAbs. Characterization of the antibody-binding sites revealed the presence of at least four s eparate epitopes.