IL-2 and IFNγ protein concentrations in supernatants obtained from bulk MLR cultures. Splenocytes obtained from recipients analyzed in Fig 5 also were studied for the production of IL-2 or IFNγ in bulk MLR cultures. Supernatants obtained at the indicated time periods were analyzed by ELISA for the concentration of IL-2 (A and C) or IFNγ protein (B and D) released in response to host (A and B) or third-party (C and D) alloantigen-bearing stimulator cells. On the x-axis is the days of MLR culture. On the y-axis is the protein concentration in picograms per milliliter. *Significant differences between the indicated groups and nonmanipulated B6 controls.