Interleukin-35 inhibited the production of histamine and pro-inflammatory cytokines through suppression MAPKs pathway in HMC-1 cells

BACKGROUND: IL-35 is a newly anti-inflammatory cytokine that belongs to the IL-12 family. Mast cells, as one of the major effector cells in the immune response system, plays an important role in the pathogenesis of chronic spontaneous urticarial (CSU). Our study aims to explore the inhibited role of IL-35 in HMC-1. METHODS: The effects of IL-35 on cell proliferation, cytokine expression, and histamine release in a human mast cell line (HMC­1) were investigated by CCK8, ELISA, or RT-PCR. The phosphorylation levels of ERK1/2, p38, and JNK1/2, in PMA plus A23187 induced HMC-1 cells was detected by Western Blot. RESULTS: We found that IL-35 significantly inhibited the proliferation of HMC-1 cells stimulated by PMA and A23187. IL-35 also down-regulates the release of histamine and the mRNA expression of IL-6 and IL-17 in activated HMC-1. Furthermore, IL-35 markedly inhibited the phosphorylation levels of ERK1/2, p38, and JNK1/2, in PMA plus A23187 induced HMC-1 cells. CONCLUSIONS: This study provides the first observations on the inhibitory and anti-inflammatory effect of IL-35 in activated HMC-1 cells. We suggest that IL35 may play an inhibited role in the pathogenesis of CSU.