Effect Of HMGB1 On MDC And Th17/Treg Imbalance In Patients With Primary Immune Thrombocytopenia

Objective: This study aimed to analyze the regulatory effect of high mobility group protein B1(HMGB1)in peripheral blood on myeloid dendritic cells(m DC)and Th17/Treg balance in patients with primary immune thrombocytopenia(ITP).Methods:Thirty newly diagnosed ITP patients admitted to the Hematology Center of Xinjiang Medical University from March 2020 to July 2022 were enrolled as research subjects,with 30 healthy examinees as controls.Flow cytometry was used to measure the proportions of m DC,Th17 and Treg cells in peripheral blood of ITP patients and healthy controls.ELISA was used to measure the expression levels of HMGB1,IL-23,IL-6,TGF-β and IL-17 in serum.Fluorescence quantitative PCR was used to measure the expression of RORγt m RNA and Foxp3 m RNA.The correlation between these cells,cytokines and platelet count was analyzed.The effect of HMGB1 on m DC and Th17/Treg balance was explored.Results: The proportion of Th17 cells and the expression levels of HMGB1,IL-6,IL-23 and IL-17 in peripheral blood of ITP patients were higher than those of normal controls(all P<0.05),while the proportion of Treg cells and TGF-β level were lower than those of healthy controls(all P<0.05).The proportion of m DC cells in ITP patients increased,but there was no statistical difference(P>0.05).Compared with healthy controls,RORγt m RNA expression increased(P<0.05),while Foxp m RNA expression level had no significant difference(P>0.05).The proportion of m DC cells was significantly correlated with the expression of IL-6 and IL-23(P<0.05);The expression of HMGB1 was significantly correlated with m DC,IL-6,IL-23,RORγt m RNA and IL-17 expression;The proportion of m DC cells and the expression level of HMGB1 were significantly negatively correlated with platelet count.Conclusion: The high expression of HMGB1 in peripheral blood of ITP patients may induce Th17/Treg imbalance by promoting the maturation of m DC and affecting the secretion of related cytokines,which may be involved in the immunological mechanism of ITP.