抗菌肽LL37联合肽聚糖对单核细胞分化的影响

Effect of antimicrobial peptides LL37 combined with peptidoglycan on the differentiation of monocytes

目的:明确LL37联合肽聚糖(PGN)对单核细胞分化的影响。方法:健康成年人外周血单核细胞经LL37、PGN、LL37+PGN刺激培养,16 h后流式细胞术(FCM)检测细胞表面CD14、CD16、髓系细胞触发受体-1(TREM-1),5天后检测不成熟树突状细胞(iDC)表面标记HLA-DR、CD1a、CD86的表达。诱导形成的iDC与异体淋巴细胞共培养3天,FCM检测Th17细胞的表达,MTT法检测T细胞的增殖。结果:LL37+PGN组与PGN组、LL37组比较,CD14++CD16+单核细胞亚群比例、细胞表面TREM-1表达、iDC比例、T细胞增殖和Th17细胞比例均明显增加,差异均有统计学意义(均P<0.05)。结论:LL37联合PGN诱导单核细胞向CD14++CD16+单核细胞亚群极化,最终导致T细胞增殖和向Th17细胞分化。

Objective：To determine the effect of antimicrobial peptides LL37 combined with peptidoglycan （ PGN） on the differentiation of monocytes. Methods：Monocytes from peripheral blood of healthy adults were cultured in the medium of LL37, PGN and LL37 combined PGN. The levels of triggering receptor expressed on myeloid cells-1（ TREM-1） , CD14 and CD16 were detected by flow cytometry （ FCM） after 16 h culture. The levels of HLA-DR, CD1a and CD86 on immature dendritic cell （ iDC） were detected by FCM after culture for 5 days. T cells proliferation and Th17 polarization were detected by MTT and FCM respectively after iDC co-cultured with lymphocyte for 3 days. Results：The percentage of CD14＋＋CD16＋monocytes and Th17, the lev-els of TREM-1 and iDC and the proliferation of T cells in the LL37 combined PGN group were obviously high-er than those in the PGN group and LL37 group （P〈0.05）. Conclusion： Antimicrobial peptides LL37 in combination with PGN can induce the monocytes differentiation into CD14＋＋CD16＋, which finally induce the proliferation of T cells and differentiation to Th17.