Assessment of granulocyte recruitment in response to chitin and thioglycolate. The accumulation of eosinophils (A,C) and neutrophils (B,D) in the BALF of chitin-challenged (A) and the peritoneum of thioglycolate (TG)–challenged Pirb^−/− or wild-type (WT) mice was assessed by differential cell counts. Data are expressed as means plus or minus SD of n = 3 (6-8 mice per experimental group); *P < .05; ns indicates nonsignificant when comparing chitin-challenged or TG-challenged WT and Pirb^−/− mice. (E) LTB₄ was assessed in the peritoneal lavage fluid of thioglycolate-challenged WT and Pirb^−/− mice. Data are expressed as means plus or minus SD of n = 3 (6-8 mice per experimental group). The dashed line represents the detection limit of the assay.