Cellular immune responses to mycobacteria in healthy and human immunodeficiency virus-positive subjects in the United States after a five-dose schedule of Mycobacterium vaccae vaccine

The safety and immunogenicity of heat-killed Mycobacterium vaccae vaccine w ere investigated in a pilot study assessing the feasibility of immunization to prevent mycobacterial disease in patients with human immunodeficiency v irus (HIV) infection. Fifteen (seven healthy and eight HIV-positive subject s) received five doses of M. vaccae vaccine. Lymphocyte proliferation assay s (LPAs) were performed using Mycobacterium avium sensitin (MAS) and M. vac cae sonicate (MVS). Vaccine was well tolerated in all 15 subjects with mini mal induration at the vaccine site. LPAs for four of seven healthy vaccinee s were positive for MAS after immunization. Median responses to MAS and MVS that were determined by LPAs were consistently higher for the eight HIV-po sitive vaccinees than for the seven healthy controls. A five-dose series of M. vaccae vaccine is safe for both healthy and HIV-positive subjects and d eserves further evaluation as a vaccine to prevent HIV-associated mycobacte rial disease.