Distinct cytokine profiles in anergizing and priming MLR cultures.

(A) For primary MLR, responder cells were cocultured in 1:1 ratio with irradiated stimulators in the presence of medium alone or with anti–B7-1 plus anti–B7-2 mAbs. At the indicated time intervals of culture, supernatants were collected and cytokine levels were analyzed by ELISA. (B) For secondary MLR, PBMCs isolated from primary cultures were rechallenged in 1:1 ratio with irradiated original stimulators, and culture supernatants were collected at the indicated time intervals and analyzed for cytokine concentrations by ELISA. Results are representative of 3 experiments. A similar pattern of results as shown here was observed when control mAb was used instead of medium alone in primary MLR. Lowest limits of detection were as follows: IL-2, 6 pg/mL; IL-4, 0.13 pg/mL; IFN-γ, 8 pg/mL; IL-10, 3.9 pg/mL.