Induction of cytotoxic responses in mice treated with iLRP RNA- ortumor RNA-transfected DCs. Balb/c mice were treated with 3 subcutaneous injections of 1 × 10⁵ OFA-iLRP RNA- or total A20 RNA-transfected syngeneic DCs and subsequently were challenged with 1 × 10⁵ A20 leukemia cells inoculated subcutaneously 7 days after the last vaccination. At day 50, after tumor injection, splenocytes from vaccinated animals were harvested and restimulated in vitro in the presence of syngeneic OFA-iLRP RNA- or total-A20 RNA-transfected DCs for 5 days. Afterward, viable cells were separated and their cytotoxic potential (OFA-iLRP-CTL, A; A20-CTL, B) was determined against A20 (H-2^d), MOPC-315 (H-2^d), and EL-4 (H-2^b) in a 4-hour ⁵¹Chromium release assay. Killing activity of polyclonal CTLs from animals receiving DC therapy 5 days after tumor inoculation was also measured (C + D).