Phenotype of CD4+ T cells responding to Rv1986.

<p>PBMC from 5 donors were stimulated either with CFP-10+ESAT-6 (A) or with Rv1986 p(61–80)+p(161–180) (B), and the phenotype of T cells producing single and multiple cytokines were analyzed using surface and intracellular cytokine staining by FACS. T cell phenotype was defined by the surface markers CD45RA and CD27: Central memory cells (TCM) are positive for CD27 and negative for CD45RA; effector memory (TEM) are negative for both CD27 and CD45RA and Terminally differentiated T cells (Tdiff) are negative for CD27 and positive for CD45RA. The results are expressed as the percentage of CD3+ CD4+ T cells. The strongest response to Rv1986 p61–80+p161–180 stimuli was the IL-2 producing central memory cells, median 0.22% (Panel B); as opposed to a median of 0.02% for CFP-10 plus ESAT-6 (p = 0.055) (Panel A). While CFP-10 and ESAT-6 induced multiple cytokine-producing TCM, Rv1986 induced predominantly single cytokine producing TCM, TEM and Tdiff cells.