Peroxisome proliferator‐activated receptor‐β/δ (PPAR
β/δ) differentially regulates cytokine production in bone‐marrow‐derived mast cells (BMMCs) in response to antigen‐dependent and antigen‐independent activation. (a) BMMCs were sensitized by IgE/dinitrophenyl‐human serum albumin (DNP‐HSA) treatment. The mRNA expression of Il6, Il10, Tnfa and Vegf in BMMCs were determined by quantitative PCR. BMMCs were exposed to (b) UVB irradiation, or treated with either (c) lipopolysaccharide (LPS) or (d) 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) for 24 hr. The mRNA expression of Il6, Il10, Tnfa and Vegf in BMMCs was determined by quantitative PCR. Values represent the mean ± SEM. Values with different superscript letters are significantly different at P ≤ 0·05.