Impaired allostimulatory activity by DCs from KS patients. (A) [³H]-thymidine incorporation by allogeneic T cells cultured with DCs from KS-positive or -negative patients in MLR. Allogeneic responses for 10 patients with KS (patients 1-10) and for 6 controls without are shown (median and interquartile ranges [IQR]). The Bonferroni-corrected P values at each DC/responder ratio is labeled below the number of stimulators on the x-axis. (B) CFSE staining of allogeneic T cells followed by stimulation with monocyte-derived DCs from a representative patient with KS (patient 6; black histogram) and a matched patient without (patient 15; gray histogram in foreground). CFSE staining enables the number of cell divisions to be observed. At least 3 divisions of T cells occur in response to DCs derived from patient 15 (1-2 divisions with patient 6).