CD40 Ligand (CD154) Does Not Contribute to Lymphocyte-Mediated Inhibition of Virulent Mycobacterium tuberculosis within Human Monocytes

Human monocytes displayed increased expression of CD40 following infection with virulent Mycobacterium tuberculosis. Nevertheless, soluble CD40 ligand (CD40L; also designated CD154) had no effect on the intracellular growth of the organism. Restriction of the intracellular growth of M. tuberculosis by peripheral blood lymphocytes and antigen-specific CD4(+) T-cell lines likewise was not reduced by blocking anti-CD40L monoclonal antibody 5c8.