B cells Can Modulate the CD8 Memory T Cell after DNA Vaccination Against Experimental Tuberculosis

BACKGROUND Although B cells are important as antigen presenting cells (APC) during the immune response, their role in DNA vaccination models is unknown. METHODS In this study in vitro and in vivo experiments were performed to evaluate the ability of B cells to protect mice against Mycobacterium tuberculosis challenge. RESULTS In vitro and in vivo studies showed that B cells efficiently present antigens after naked plasmid pcDNA3 encoding M. leprae 65-kDa heat shock protein (pcDNA3-Hsp65) internalization and protect B knock-out (BKO) mice against Mycobacterium tuberculosis infection. pcDNA3-Hsp65-transfected B cells adoptively transferred into BKO mice rescued the memory phenotypes and reduced the number of CFU compared to wild-type mice. CONCLUSIONS These data not only suggest that B cells play an important role in the induction of CD8 T cells but also that they improve bacterial clearance in DNA vaccine model.