DELAYED-TYPE HYPERSENSITITY ELICITED BY SYNTHETIC PEPTIDES COMPLEXED WITH MYCOBACTERIUM-TUBERCULOSIS HSP-70

Four synthetic peptides bearing dominant CD4(+) T-cell epitopes of the 19000 and 38000 MW proteins of Mycobacterium tuberculosis were used t o provoke a delayed-type hypersensitivity (DTH) reaction in mice previ ously immunized with recombinant 19000 and 38000 MW proteins. It was f ound that an effective enhancement of the DTH reaction was obtained if the peptides were administered as a complex with M. tuberculosis hsp 70 protein. The increase in reactivity was not obtained when hsp 70 an d peptide were co-injected at the same site, but no in complex, or whe n the specific peptide was displaced from the complex by an irrelevant peptide with high capacity to bind hsp 70. One of the antigenic pepti des whose capacity to complex with hsp 70 is low, failed to show the e nhancement of DTH when injected together with hsp 70.