不同年龄人牙周膜干细胞对T细胞增殖分化的影响

Effect of human periodontal stem cells on T cell proliferation and differentiation at different ages

目的研究年龄因素影响下人牙周膜干细胞(periodontal ligament stem cells,PDLSC)对T细胞增殖分化功能的影响。方法获取10~15岁、30~35岁、>60岁患者健康离体牙男女各5例,分离培养获得人PDLSC,对比各组细胞衰老相关指标;采用免疫磁珠法分离获取20~30岁健康患者的外周血T细胞;将PDLSC与T细胞共培养48 h后观察T细胞增殖水平差异;检测共培养后T细胞功能亚群比例变化、PDLSC免疫调节因子基因表达水平差异。结果PDLSC细胞增殖能力随年龄增加而降低,衰老指标逐渐增高(P<0.05)。与PDLCS共培养48 h后,T细胞增殖受抑制水平随着PDLSC年龄增加,抑制作用逐渐降低(P<0.05);Th1/Th2细胞比例、Th17细胞比例随年龄增加而增加,而Treg比例随年龄增加而降低(P<0.05);PDLSC表达TGF-β、IDO、HGF基因表达随年龄增加而降低(P<0.05);随年龄增加牙周膜干细胞P53、P21、P16基因表达逐渐增加(P<0.05)。结论PDLSC对T细胞免疫抑制作用受供体年龄的影响,并随着年龄增加对T细胞增殖抑制、功能亚群分化调节能力降低。

Objective To investigate the effects of age factors on the impact of periodontal ligament stem cells(PDLSC)on T cell proliferation and differentiation function.Methods PDLSC were isolated and cultured from 5 healthy male and female patients aged 10~15 years,30~35 years,and over 60 years.The cells were compared for cellular senescence-related markers.Peripheral blood T cells from healthy patients aged 20~30 years were isolated using immunomagnetic beads.The PDLSC and T cells were co-cultured for 48 hours to observe differences in T cell proliferation.Changes in T cell functional subsets and differences in the expression levels of immunomodulatory factors were also examined post co-culture.Results The proliferative capacity of PDLSC decreased with age,with senescence markers gradually increasing and the expression levels of P53,P21,and P16 genes increasing with age(P<0.05).The level of T cell proliferation inhibition in co-culture decreased with the age of PDLSC,and the inhibitory effect gradually decreased(P<0.05).The Th1/Th2 ratio and Th17 cell percentage increased with age,while the Treg percentage decreased with age,The expression levels of TGF-β,IDO,and HGF genes in PDLSC decreased with age(P<0.05).Conclusion The immunosuppressive effect of PDLSC on T cells is affected by the age of the donor,and the ability to inhibit T cell proliferation and regulate functional subset differentiation decreases with increasing age.