摘要
Abstract
Objective:To explore the mechanism of concentrated growth factor(CGF)remodeling the immune homeostasis of diabetes foot ulcer(DFU)by inducing recruitment and functional activation of myeloid-derived suppressor cells(MDSCs),and to evaluate the impact of glycemic control on the efficacy of CGF,providing a new immune regulation strategy for clinical use.Methods:DFU model of C57BL/6 mice induced by streptozotocin(STZ)was established and randomly divided into CGF group(wound covered with autologous CGF gel),control group(PBS treatment),and CGF combined with glycemic intervention group(CGF+GI group,receiving daily subcutaneous insulin injection to maintain blood glucose at 8～12 mmol/L based on CGF treatment).Flow cytometry was used to detect proportion of MDSCs(CD11b⁺ Gr-1⁺)and expressions of functional molecules ARG-1/iNOS in the wound;immunohisto-chemistry/fluorescence analysis for tissue localization;ELISA quantification of inflammatory factors(IL-10,TGF-β1,TNF-α,IL-6);principal component analysis(PCA)integrated multidimensional immune indicators;mediation effect model verified pathway mecha-nism.Results:On the 7th day,proportion of MDSCs in CGF group reached its peak(P<0.001),and mean fluorescence intensity(MFI)of ARG-1 was significantly increased(P<0.001).Compared with CGF group,CGF+GI group exhibited a further increase in MDSCs proportion(P<0.05)and ARG-1 MFI(P<0.01)on day 7,along with higher levels of anti-inflammatory factors IL-10 and TGF-β1(P<0.05)and lower levels of pro-inflammatory factors TNF-α and IL-6(P<0.05).Anti-inflammatory factors IL-10 and TGF-β1 were significantly up-regulated,while pro-inflammatory factors TNF-α and IL-6 were significantly inhibited(both P<0.001).The median healing time in CGF group was shortened to 12.5 days(control group 18.7 days,P<0.001),and PCA confirmed that the"immunosup-pressive/repair axis"(contribution rate 46.37%)dominated steady-state reconstruction.The mediating effect showed that CGF accelerates healing through a chain pathway of"MDSCs recruitment → ARG-1/iNOS ↑→ anti-inflammatory factors ↑"(β=0.263).Conclusion:CGF continuously activates ARG-1/iNOS immunosuppressive function of MDSCs,synergistically regulates inflammatory factor net-work,reconstructs the immune homeostasis of DFU,significantly promotes wound healing,and glycemic control can further enhance the immunomodulatory effects of CGF,and provides a new strategy for DFU immune targeted therapy.关键词
浓缩生长因子/髓源性抑制细胞/糖尿病足溃疡/免疫稳态Key words
Concentrated growth factor/Myeloid-derived suppressor cells/Diabetes foot ulcer/Immune homeostasis分类
医药卫生
