Mycobacterial Infection Primes T Cells and Macrophages for Enhanced Recruitment of Neutrophils

Abstract: C57BL/6 mice intraperitoneally infected with Mycobacterium bovis BCG (substrain Pasteur) recruited significantly higher numbers of neutrophils after an in-traperitoneal inoculation of either BCG protein antigen or of endotoxin than uninfected control mice. Antigen-induced neutrophil recruitment was mediated by T cells of both CD4 and CD8 phenotype and was also observed in the C5-deficient DBA/2 mouse strain. The adoptive transfer of immune serum did not prime mice for en-hanced antigen-mediated recruitment of neutrophils. The endotoxin-mediated recruitment of neutrophils was also enhanced in infected as compared to uninfected DBA/2 mice. Finally, endotoxin-pulsed purified macro-phages from infected CS7BL/6 mice recruited higher numbers of neutrophils than endotoxin-pulsed macro-phages from normal mice in an adoptive transfer to pen-toneal cavities of naive recipient mice. These data show that during mycobactenial infection, T cells and macro-phages are primed for recruitment of neutrophils after being triggered in specific or nonspecific ways. This may represent a means to cope with secondary infections by allowing for extensive neutrophil infiltration readil