CHARACTERIZATION OF ANTIGENS RECOGNIZED BY NEW MONOCLONAL-ANTIBODIES RAISED AGAINST CULTURE FILTRATE PROTEINS OF MYCOBACTERIUM-BOVIS BACILLUS-CALMETTE-GUERIN

Effective protection against Mycobacterium tuberculosis may be achieve d in experimental animals by immunization with proteins secreted by tu berculous bacilli in the extracellular milieu during growth. III this study, monoclonal antibodies were raised against Mycobacterium bovis b acillus Calmette-Guerin (BCG) culture filtrate proteins or live BCG, i n an attempt to identify novel mycobacterial secretion antigens: the l ocalization of the antigens recognized by the monoclonal antibodies wi thin the mycobacterial cell was studied and interspecies reactivity wa s also investigated. The monoclonal antibodies obtained recognized pro teins of molecular mass ranging from 5 to 82 kDa, with a prevailing fr equency in the 30 kDa region. Three of the monoclonal antibodies recog nized proteins present only in culture filtrates, one reacted with a c ytoplasmic antigen, while the remaining antibodies recognized componen ts which were mainly associated with the cell wall and the cytoplasmic membrane. The chemical nature and possible identity of the antigens w as checked. Three monoclonal antibodies are likely to react with novel mycobacterial antigens of 5, 42 and 82 kDa, respectively. (C) 1998 Fe deration of European Microbiological Societies. Published by Elsevier Science B.V.