8,9-epoxyeicosatrienoic acid (EET) inhibited B-cell antibody production in C57BL/6 and ApoE−/− mice. ELISA of levels of IgM and IgG (A and B) in the supernatant of cultured B cells from C57BL/6 mice after incubation for 3 days with 1 µM EETs plus 5 µg/ml lipopolysaccharide (LPS) with or without 50 ng/ml IL-4. ELISA of levels of IgM (C and E) and IgG (D and F) in the supernatant of cultured B cells from C57BL/6 mice with indicated doses of 8,9-EET (C and D) or with 1 µM 8,9-EET for the indicated times (E and F) with 5 µg/ml LPS with or without 50 ng/ml IL-4. (G and H) ELISA of production of IgM and IgG by B cells from ApoE−/− mice and age- and sex-matched C57BL/6 control mice after incubation for 3 days with the indicated doses of LPS with or without IL-4 (50 ng/ml). *, P