Figure 1. Reduced recruitment of Th1 and Th2 cells into the airways of mice depleted of Gr-1⁺ cells.

(A) Mice received Th1 and Th2 cells or PBS i.v. were challenged i.n. with the low dose of OVA as described in Materials and Methods. A group of mice were treated with an anti-Gri-1 mAb one day before the transfer of in vitro cultured Th cells and at the same time of the 1^st OVA challenge, while other groups of mice received an isotype control mAb as indicated. Three days after Ag challenge DO Th1 cells (gray bars) and Th2 cells (black bars) were recovered from the BAL and enumerated by flow cytometry. (B) Th2 cells were counted in BAL of mice that received Th2 cells only prior to challenge i.n. with the high dose of OVA. (C) Numbers of Th1 cells in the airways were determined 3 days after high or low dose OVA challenge of mice that received Th1 cells only. Data show mean ± SEM (n = 5 mice per group; *p<0.05 and **p<0.01, vs. groups treated with control mAb). Similar results were obtained in at least 3 replicate experiments.