PGHS-1 and PGHS-2 expression in nonimmunized and allergic wild-type, PGHS-1–/–, and PGHS-2–/– mice. Wild-type, PGHS-1–/–, and PGHS-2–/– mice were divided into treatment groups, and the abundance of PGHS-1 and PGHS-2 protein in the lungs was determined by Western blotting using immunospecific antibodies as described in Methods. Results are representative of experiments with 18 different animals (3 mice in each of the 6 groups). Lane 1, PGHS-1–/– mice, allergic; lane 2, PGHS-2–/– mice, allergic; lane 3, wild type mice, allergic; lane 4, PGHS-1–/– mice, nonimmunized; lane 5, PGHS-2–/– mice, nonimmunized; lane 6, wild-type mice, nonimmunized.