Detection of IFNγ-producing lymphocytes by flow cytometry following stimulation with <i>Salmonella</i>.

<p>Dot plots of CD4⁺-T cells (A, C and E) and γδ-T cells (B, D and F) from human peripheral blood from one healthy adult, either unstimulated (A and B), or stimulated with PMA (C and D) or <i>S</i>. Typhimurium D23580 homogenate (E and F), showing intracellular production of IFNγ and expression of CD69. Numbers within gates indicate percentage of IFNγ-producing cells. Each dot represents one cell.