EVIDENCE FOR THE EARLY RECRUITMENT OF T-CELL RECEPTOR GAMMA-DELTA(-CELLS DURING RAT LISTERIOSIS() T)

We have previously reported that heat-shock protein (hsp) 60-reactive T-cell receptor (TCR)gamma delta(+) T cells appear in the peritoneal c avity during the early stage of infection with Listeria monocytogenes in mice. In this study, we examined the kinetics of TCR gamma delta(+) T cells during listeriosis in F344 rats by flow cytometry using a V65 monoclonal antibody (mAb) directed to a constant determinant of rat T CR gamma delta chains. TCR gamma delta(+) T cells significantly increa sed in the peritoneal cavity on day 6 and then decreased by day 10 aft er infection, in parallel with the kinetics of hsp 60 expression in th e peritoneal macrophages during listeriosis in F344 rats. Most of the early appearing TCR gamma delta(+) T cells were of the CD4(-)CD8 alpha beta(+)CD5(+) lymphocyte function-associated antigen (LFA)-1 alpha(hi gh) CD45RC(-) interleukin-2 receptor (IL-2R) alpha(-) phenotype, altho ugh a significant fraction of the TCR gamma delta(+) T cells expressed CD8 alpha only. The increase in TCR gamma delta(+) T cells during lis teriosis was prominent in F-1 (F344 x Lewis) rats but only marginal in Lewis rats, which was correlated with the expression level of hsp 60 in the peritoneal macrophages. The peritoneal TCR gamma delta(+) T cel ls in naive F344 rats appeared to proliferate significantly in respons e to recombinant hsp 60 (rhsp 60) derived from Mycobacterium bovis bac illus Calmette-Guerin (BCG). These results imply that the early appear ance of hsp 60-reactive TCR gamma delta(+) T cells during listerial in fection can be generalized across species.