Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: February 17, 2014
Publication Date: May 2, 2014
Citation: Maggioli, M.F., Palmer, M.V., Vordermeier, H.M., Whelan, A.O., Waters, W.R. 2014. Bovine central memory T cells are highly proliferative in response to bovine tuberculosis infection. Proceedings of American Association of Immunologists Annual Meeting. p. 22. Technical Abstract: Long-term (i.e., 14 days) cultured IFN-gamma ELISPOT assays measure central memory T cell (Tcm) responses in both humans and cattle. With bovine tuberculosis, vaccine-elicited long-term IFN-gamma ELISPOT responses correlate with protection. In other species, Tcm’s pose low activation threshold and are highly proliferative. It has been shown that Tcm’s accounts for 75% of long-term cultured cells. The objective of this study was to access the proliferative capability of Tcm cells compared to 6 day cultured cells (n = 6) in response to aerosol Mycobacterium bovis infection. Long-term cultured PBMCs from infected cattle were stimulated with M. bovis purified protein derivative (PPDb), rESAT-6:CFP10 (E:C), rTB10.4 and rAg85A for 13 days. Next, cells were stained with CellTrace dye and re-stimulated with E:C in the presence of fresh autologous adherent cells for an additional six days (20 days). In response to E:C, long-term cultured were mainly CD4+ cells and were more proliferative (~ 48%) than 6d cultured cells (27%; p=0.001). Long-term cultured cells were: ~30% Tcm (CCR7+, CD45RO+), ~48% Tem (CCR7-, CD45RO+), ~8% effector (CCR7-, CD45RO-) and <1% of naïve cells (CCR7+, CD45RO-). Six day cultured cells were: ~16% Tcm (p=0.01), ~47% Tem, ~42% effector (p=0.001) and < 1% naïve cells. These findings demonstrate that bovine Tcm cells present high proliferative capability as compared to short-term cultured cells.