Fig. 4.

Specific lysis of various targets by the CTLs generated in vitro. DCs from HLA-A2+ healthy donors were transduced with rAAV/CML28 and used to stimulate CTL response. Cytotoxic reactivity was determined by LDH assay. The T cells resulting from untreated DCs and the mock DCs served as negative control and comparative control, respectively. Note that the CTL derived from rAAV/CML28 transduced DCs showed apparently lytic activity against HepG2 at different ratios, whereas, no significant lytic activity was seen in the controls (a). Even thought the low-level lysis was observed in the HL-60 and K562 cells, which may due to the non-specific lysis mediated by the NK cell population among the effecor cells, still note that the CTL response stimulated by rAAV/CML28 transduced DCs is specific to the HLA-A2 positive cells expressing the tumor antigen CML28 (b). CML28-specific CTL lysed the CML28 positive primary tumor cells from HLA-A2 positive leukemia patients, but not from the HLA-A2 negative leukemia patient (c). Data represent means ± SD of three independent experiments