Role Of Th17/Treg Immune Imbalance In Post-stroke Depression

Objective:Immunoin flammatory response plays an important role in PSD.It has been confirmed that Th17 and Treg cells play a key role in the pathogenesis of depression,but the role of Th17/Treg cell immune imbalance in PSD has not been confirmed.In this study,Th17 and Treg cell absolute counts were carried out between PSD patients and non-PSD patients,and between different depression groups by flow cytometry and ELISA,respectively.Comparing the serum levels of cytokines,and analyzing the trend of the correlation between cytokines and Th17/Treg cell ratio,further evaluating the immune imbalance in patients with PSD.It provides a new target for early prevention and treatment of PSD.Methods:1.? The clinical data of age,sex,smoking,drinking,diabetes,heart disease,hypertension and stroke sites were collected and compared within 24 hours of admission.Meanwhile,the patients' CES-D,NIHSS,MMSE and ADL scores were evaluated.2.Within 10-14 days of diagnosis,patients with acute ischemic stroke were divided into PSD group and non-PSD group by HAMD-24 score.60 patients with PSD and 60 patients without PSD were selected.The PSD group was further divided into mild(8-20),moderate(21-35)and severe(more than 35)according to HAMD-24 score.All of them were completed by neurologists trained in scale.3.Flow cytometry was used to detect the absolute count of peripheral blood lymphocyte subsets,total T cells,CD4 + T cells,Th1 cells,Th2 cells,Th17 cells and Treg cells,and the ratio of Th1/Th2 and Th17/Treg.The difference of CD4 + T lymphocyte subsets between PSD group and non-PSD group and between different depression degree groups was compared.4.The levels of IL-6 and IL-10 in peripheral blood were measured by ELISA.Thedifferences of inflammatory cytokines between PSD group and non-PSD group were compared,and the correlation between the ratio of inflammatory cytokines and Th17/Treg and the degree of depression was analyzed.Results:1.There were no significant differences in age,sex,smoking,alcohol consumption,heart disease,hypertension,CES-D,NIHSS,MMSE,ADL score and stroke location among the groups.Blood sugar in PSD group was significantly higher than that in non-PSD group,and there were significant differences between the two groups.2.Compared with non-PSD group,the Th17/Treg ratio of peripheral blood in PSD group increased significantly,with statistical difference(P < 0.001),Treg cell count decreased,and there was statistical significance between the two groups(P < 0.05);Th17/Treg ratio was higher in severe depression group,followed by moderate depression group,and the lowest in mild depression group,with statistical significance among the three groups.3.The level of IL-6 in PSD group was significantly higher than that in non-PSD group,but there was no significant difference among groups with different degrees of depression.The level of IL-10 in PSD group was significantly lower than that in non-PSD group,the lowest in severe depression group and the highest in mild depression group,with statistical significance(P < 0.05).IL-6 level was positively correlated withTh17/Treg ratio,while IL-10 level was negatively correlated with Th17/Treg ratio.Conclusions:1.The imbalance of Th17/Treg ratio in patients with PSD indicates the disorder of immune inflammation,suggesting that the imbalance of Th17/Treg cell immunity is related to the occurrence and development of PSD.2.Inflammatory cytokines IL-6 and IL-10 may be key regulators of Th17/Treg immune imbalance.