Effector T cells with a TH2/Tc2 phenotype at tumor site of patients with B-NHL. (A) Intracellular staining for IL-4 and IFN-γ production in gated CD4⁺ or CD8⁺ T cells isolated from involved lymph nodes of two patients with FL (A and B). Lymphocytes from patient A were tested without prior activation against autologous DCs either unloaded (i) or loaded with killed autologous B-cell tumor (ii). Lymphocytes from patient B were tested without prior activation either alone (iii) or against live autologous B-cell tumor (iv). (B) Lymphocytes from patient A, isolated from the same lymph node as in panel A, were cultured for 2 weeks with DCs loaded with killed autologous B-cell tumor and then tested either alone (i) or against live autologous B-cell tumor (ii), allogeneic B-cell tumor (iii), or after activation with PMA + ionomycin (iv). Numbers in the dot plots indicate the fraction of positive cells in each quadrant.