Fig. 3.

Low-dose CPA can replace PC-61in enhancing IL-2-activated NK function. A, additional groupswere added in the regimen of Fig.1A, inwhich a single intraperitoneal injection of CPA at100 mg/kg was administered either in place of the PC-61antibody or 24h after the final injection of IL-2. In addition, groups that received an injection of the NK cell depleting asialo-GM-1antibody 24h before treatment with PC-61or CPA were also included. B, 48 h following the final injection of IL-2, splenocytes from treated mice were recovered, cDNA was prepared, and expression of the MMP-2 gene was analyzed by PCR. Equal loading of RNA was shown using amplification of GAPDH. Representative of three mice per group and of multiple repeat experiments. C, experiment of A and B was repeated with fewer treatment groups. Five hundred thousand splenocytes from treated mice were recovered and plated for 48 h in vitro. Supernatants were then assayed forMMP-2 by ELISA (R&D Systems). D, splenocytes from the 3 mice per group in A and B above were also plated with B16 target cells at an effector splenocytes:target ratio of10:1, and 48 h later, supernatants were assayed for IFN-γ by ELISA.