TLR2和TLR4对新生儿免疫细胞中Th1/Th2细胞因子的影响

Effects of TLR2 and TLR4 on Th1/Th2 Cytokines in Neonatal Immune Cells

为了探讨TLR2和TLR4对新生儿免疫细胞中Th1／Th2细胞因子的影响，本研究采用LPS和PGN刺激新生儿脐带血单个核细胞、成人外周血单个核细胞和人肥大细胞，并用特异性信号分子抑制剂PD98059处理单核细胞和肥大细胞，测定不同处理组ERK的磷酸化强度、IL-6、IL-12、IL-13和RANTES细胞因子水平以及HMC-1细胞脱颗粒情况。研究显示，经过LPS或PGN刺激后，单核细胞和肥大细胞中ERK的磷酸化强度与对照组相比均显著升高（p〈0．05）；通过LPS和PGN共同刺激后，脐带血单个核细胞中ERK的磷酸化高于单个配体刺激。在添加了ERK特异性抑制剂PD98059后，LPS和PGN共刺激的脐带血单个核细胞中IL-6、IL-12和IL-13浓度显著下降，而RANTES未显示明显抑制。经PGN刺激后HMC-1细胞的B-hexos-aminidase释放率高于LPS，并且LPS＋PGN共刺激的β-hexosaminidase释放率高于单一配体刺激。本研究表明，TLR2／TLR4与LPS／PGN结合后，通过激活ERK信号通路来调节新生儿免疫细胞中Th1／Th2细胞因子，LPS和PGN共刺激对调节新生儿免疫细胞中IL-6、1L-12和IL-13细胞因子具有协同作用。

In order to investigate the effect of TLR2 and TLR4 on Th1/Th2 cytokines in neonatal immune cells, LPS and PGN were used to stimulate neonatal umbilical cord blood mononuclear cells, adult peripheral blood mononuclear cells and human mast cells, and then mononuclear cells and mast cells were treated with specific signal molecular inhibitor PD98059. The phosphorylation intensities of ERK, expressions of IL-6, IL- 12, IL- 13 and RA- NTES cytokine, and degranulations of HMC-1 cells in different treatment groups were analyzed. Results showed that the phosphorylation of ERK in monocytes and mast cells was significantly increased after LPS or PGN stimulation （p〈0.05）. After stimulation with LPS and PGN, the phosphorylation of ERK in umbilical cord blood mononuclear cells was higher than that of single ligand stimulation. The concentration of IL-6, IL-12 and IL-13 in umbilical cord blood mononuclear cells stimulated by LPS and PGN was significantly decreased after addition of ERK-specific inhibitor PD98059, whereas RANTES did not show significant inhibition. The release rate of 13-hexosaminidase in HMC-1 cells stimulated with PGN was higher than LPS＇ stimulation, and the release rate of [3-hexosaminidase in HMC-1 cells with LPS＋PGN co-stimulation was higher than single ligand stimulation. This study indicated that, after binding to LPS/PGN, TLR2/TLR4 regulates Th1/Th2 cytokines in neonatal immune cells by activating ERK signaling pathway. Co-stimulation of LPS and PGN has a synergistic effect on the regulation of IL-6, IL-12 and IL-13 cytokines in neonatal immune cells.