T cell regulation of the chronic peritoneal neutrophilia during mycobacterial infections

Intraperitoneal infection of mice with mycobacteria induces the persistent mobilization of neutrophils to the infected peritoneal cavities. The recruitment of the neutrophils was mediated by the immune system since it was enhanced by immunization and reduced in T cell-deficient nude and SCID mice. Anti-mitotic treatments with cyclophosphamide or X-rays led to a reduction in the number of mononuclear cells in the peritoneal cavity of infected mice, followed by a reduction in neutrophil numbers despite the presence of a normal circulating pool of neutrophils. The depletion of T cells with antibodies during mycobacterial i.p. infection led to a reduction in the number of neutrophils. Such a reduction was more extensive if the antibodies were administered early. Our data suggest that T cells are partially involved in the direct recruitment of neutrophils during chronic mycobacteriosis but they also play a role in the priming of other cell types for the mobilization of these phagocytes.