IMMUNIZATION OF HEALTHY ADULT SUBJECTS IN THE UNITED-STATES WITH INACTIVATED MYCOBACTERIUM-VACCAE ADMINISTERED IN A 3-DOSE SERIES

Heat-killed Mycobacterium vaccae vaccine was administered in a three-d ose intradermal schedule to 10 healthy adult volunteers at 0, 2, and 1 0 months, Local and systemic side effects were monitored and vaccine s ite reactions were measured and photographed at visits 2 days, 14 days , and 2 months after each dose. Reactions to skin tests with purified protein derivative (PPD) and Mycobacterium avium sensitin (MAS) and ti ters of antibody to arabinose lipoarabinomannin were determined at bas eline and after each dose of vaccine. Lymphocyte proliferation respons es to MAS were determined after the final dose of vaccine. Immunizatio n was safe and well tolerated, with maximal induration (range, 6-25 mm ) at 2 days, PPD skin test conversions did not occur, Seven subjects c ompleted the three-dose schedule; preexisting immunologic responses to mycobacteria were boosted in three, and a new response was elicited i n one. M. vaccae vaccine is safe and induces measurable immunologic re sponses to mycobacterial antigens in some healthy adults.