Figure 4

Induction of overall cytolytic activity by CXCR3⁺CD4⁺/DCs. WT-1-specific CTL was generated from normal donors, as described in Methods. (A) Cytotoxicity of T-cells generated with three types of DCs against WT-1 were tested in response to peptide-pulsed LCLs (10 µg/ml) at E:T ratios ranging from 40:1 to 20:1 in a standard 4-h ⁵¹Cr release assay. Results are expressed as percentage of specific lysis; the percentage of lysis in the presence of peptide (filled) and the percentage of lysis in the absence of peptide (empty). Asterisk indicates that the cytolytic activity of CTLs generated with CXCR3⁺CD4⁺/DC at E:T ratio of 40:1 was significantly higher than that obtained with CD4⁺/DC (^*P = .04). (B) Lytic units against WT-1 were calculated from cocultures. The data from Figure 3A and 4A were combined to represent the lytic units resulting from the exposure of effectors to targets. One lytic unit is defined as 30% specific lysis. The calculated lytic unit is the yield of effectors (from Figure 3A) divided by the number of cells required to achieve a single lytic unit. One representative experiment of three performed is shown.