Immunological evaluation of novel Mycobacterium tuberculosis culture filtrate proteins

Culture filtrate from Mycobacterium tuberculosis contains molecules which can promote protective immunity to tuberculosis in animal models. Six novel proteins in the region of 17-29 kDa were purified and investigated for their immunological relevance in M. tuberculosis-infected mice, guinea pigs and tuberculosis patients. The proteins CFP17, CFP21, CFP25 and CFP29 were all identified as strong interferon-gamma inducers in M. tuberculosis-infected mice and in tuberculosis patients. The CFP21 protein is encoded in the genomic region RD-2 which is deleted from a number of BCG strains and the diagnostic potential of this antigen was evaluated.