Tuberculosis in aged gammadelta T cell gene disrupted mice.

In young mice exposed to aerosol infection with Mycobacterium tuberculosis removal of the gammadelta T cell population by targeted gene disruption does not affect the expression of host resistance, but does influence the integrity of the early granulomatous response. The current study demonstrates that in aged gammadelta T cell gene disrupted mice similar immunopathologic changes ensued in both gene knockout and wild type control mice. Changes in cell surface marker expression, evident in other gene knockout models, was not observed in the aged gammadelta T cell knockout mice. These data imply that gammadelta T cell functions previously observed in young mice become much less important as the animal ages.