Recombinant methylated mycobacterial heparin-binding hemagglutinin antigen

摘要

Immunogenic recombinant peptide (I) is the methylated form of an expression product of a nucleic acid (II) that encodes a mycobacterial heparin-binding hemagglutinin antigen (HBHA), especially from Mycobacterium bovis BCG or M. tuberculosis, is new. Independent claims are also included for: (1) processes for preparing (I); (2) recombinant vector that encodes HBHA and at least one recombinant mycobacterial methyltransferase; (3) host cell that harbors a vector of (2); (4) (I) produced by method (1); and (5) immunogenic composition containing any methylated form of HBHA. ACTIVITY : Tuberculostatic. Mice were immunized with native HBHA (5 mu g), 3 times at 2 week intervals. The titer of HBHA-specific immunoglobulin G (IgG) was then 5000, principally IgG1. Ten weeks after the first immunization, the animals were challenged with 10 5> colony-forming units (cfu) of M. tuberculosis and after 6 weeks the number of cfu in various organs was measured. Compared with adjuvant-only controls, the vaccination caused a reduction, in log10 cfu, of 0.94 in liver; 0.85 in spleen and 0.93 in lungs. Equivalent results (not quoted) were achieved with recombinant methylated HBHA. MECHANISM OF ACTION : Vaccine.