a) Wild type (wt) or perforin and IFN-γ double deficient (PKO/GKO) mice were vaccinated s.c. with D5-G6 tumor cells and TVDLN were harvested 8 days later. Lymph node cells were stimulated in vitro with anti-CD3 for two days and then expanded for three days in 60 IU/ml IL-2. Effector cells were harvested and 35 × 106 T cells were adoptively transferred into animals with established 3-day D5 pulmonary metastases. IL-2 (90,000 IU) was administered daily i.p. for four consecutive days following adoptive transfer.
b) Purified control human IgG or LT-βR-Fc (250 μg) was directly administered i.v. after adoptive transfer of the TE and for the following 3 days once per day.
c) Mice were sacrificed 13 days following i.v. inoculation of tumor and the number of pulmonary metastases enumerated in a blinded fashion. Results presented are the mean of 5 mice.
d) p < 0.05 compared to IL-2 alone treated controls.