TY - JOUR T1 - In vivo and in vitro activation and expansion of gammadelta T cells during Listeria monocytogenes infection in humans. JF - Infection and Immunity JO - Infect. Immun. SP - 4267 LP - 4272 VL - 65 IS - 10 AU - Jouen-Beades, F AU - Paris, E AU - Dieulois, C AU - Lemeland, J F AU - Barre-Dezelus, V AU - Marret, S AU - Humbert, G AU - Leroy, J AU - Tron, F Y1 - 1997/10/01 UR - http://iai.asm.org/content/65/10/4267.abstract N2 - Serial flow cytometry analyses of peripheral blood mononuclear cells obtained from 8 patients infected with Listeria monocytogenes showed a higher percentage (P &lt; 0.01) of gammadelta T cells (median, 11.7; range, 3.7 to 35.3) than did 16 age-matched uninfected controls (1.7, 0.4 to 13). Most in vivo-expanded gammadelta T cells expressed the Vgamma9 and Vdelta2 gene products and displayed a memory phenotype (CD45RO[high]), and patients' gammadelta T cells expressed significantly more (P &lt; 0.01) activation marker HLA-DR than did controls (19.8% [median] and 0.9 to 87.6% [range] versus 2.3% and 0 to 4.7%, respectively). When peripheral blood mononuclear cells from normal donors were cultured in vitro with heat-killed Listeria cells, analysis of CD25 and HLA-DR expression on gammadelta and alphabeta T cells indicated that a high percentage of gammadelta T cells was activated early compared to alphabeta T cells. In addition, depletion of gammadelta T cells before culture abrogated the early lymphocyte proliferative response induced by the pathogen. Taken together, these results argue for the involvement of gammadelta T cells during L. monocytogenes infection in humans. ER -