Effect Of Remote Ischemic Postconditioning On CD4⁺T Cell Sub-sets In Peripheral Blood Of Patients With Cerebral Infarction And Its Mechanism

Objective: 1、To explore the neuroprotective effect of distant ischemic postconditioning and its effect on the proportion of Th1,Th2,Th17 and Treg cells in CD4⁺T cells.2、To investigate the effects of distant ischemic post-treatment on the expression of differentiation-related transcription factors in each subgroup.Methods: 1.According to the inclusion and exclusion criteria,a total of 35 patients with acute anterior circulation cerebral infarction who were admitted to the Department of Neurology,The First Hospital of Jilin University from May 2021 to November 2021 and within 3 days of the onset of post-RIC treatment were selected,and they were divided into the post-RIC group（n = 14）and the conventional treatment group（n = 21）according to their will.During the same period,15 volunteers with no difference in age,gender,hypertension,diabetes history and no cerebral infarction or inflammation-related diseases were recruited as the non-infarction group.The conventional treatment group received improvement of circulation,nutritional nerve,anti-platelet aggregation,stabilization of plaque and symptomatic treatment.In addition to conventional treatment group,patients in the post-RIC group were given post-RIC treatment,i.e.,the upper limbs were pressurized for 5min reperfusion for 5min with ischemia adaptation training instrument,5 cycles per time,twice a day for consecutive 7 days.The non-infarct group only received symptomatic treatment for risk factors.In the post-RIC group,peripheral fasting venous blood was taken in the morning before,3and 7 days after post-treatment,while in the conventional treatment group,blood was collected at the same time,and the blood collection time was recorded as 0d,3d and 7d.NIHSS score was performed on admission and 7 days after treatment.In the noninfarction group,peripheral fasting venous blood was taken only once.The general clinical data of the patients were recorded.Flow cytometry and Flowjo10 software were used to determine the proportion of Th1,Th2,Th17 and Treg subsets in CD4⁺T cells during the third blood collection.The mRNA expression levels of transcription factors（T-bet GATA3,RORγ T,Foxp3）related to differentiation in peripheral blood mononuclear cells were determined by real-time quantitative PCR.2.The correlation between the proportion of Th1,Th2,Th17 and Treg cells in CD4⁺T cells and NIHSS score in patients with acute cerebral infarction before treatment was analyzed,and simple linear correlation analysis was further performed.The proportion of CD4⁺T cells in each subgroup was compared between the conventional treatment group and the non-infarction group.3.The difference in NIHSS score between the conventional treatment group and the post-RIC group was compared,as well as the difference in the proportion of Th1,Th2,Th17 and Treg cells in CD4⁺T cells in each blood collection between the two groups.4.The mRNA expression levels of differentiation-related transcription factors（TBET,GATA3,RORγ T,Foxp3）in each subgroup were compared between the conventional treatment group and the post-RIC group.Results: 1、Within 3 days of onset of cerebral infarction,the proportion of Th2 subsets in CD4⁺T cells in peripheral blood of patients was negatively correlated with NIHSS score（r =-0.481,P=0.005）,the ratio of Th1/Th2 was positively correlated with NIHSS score（r=0.389,P=0.028）,and There was no significant correlation between Th1,Th17,Treg or Th17/Treg and NIHSS score.2、In triple blood sampling,the proportion of Th2 subsets in CD4⁺T cells in the conventional treatment group was always lower than that in the non-infarction group（P=0.001,P=0.006,P=0.008）,and the ratio of Th1/Th2 was always higher than that in the non-infarction group（P=0.008,P=0.03,P=0.049）.At the time of the first blood collection,the proportion of Treg subsets in CD4⁺T cells in the conventional treatment group was lower than that in the non-infarct group（P=0.022）,and the ratio of Th17/Treg was higher than that in the non-infarct group（P=0.022）.The proportion of Th1 subsets in CD4⁺T cells in the conventional treatment group was not significantly different from that of the non-infarct group.3、The ΔNIHSS score in the post-RIC group was higher than that in the conventional treatment group（P=0.002）.4、The proportion of Th2 subsets in CD4⁺T cells in peripheral blood of postRIC group was higher than that in the conventional treatment group at 3d and 7d（P=0.001,P=0.041）,and the ratio of Th1/Th2 was lower than that in the conventional treatment group（P=0.05,P=0.006）.5、GATA3 mRNA expression level in PBMC of patients in the post-RIC group was significantly higher than that in the conventional treatment group at 3d and 7d（P=0.032,P=0.035）.Conclusion: 1、The proportion of Th2 subsets in CD4⁺T cells in peripheral blood of patients with cerebral infarction within 3 days of onset was negatively correlated with the severity of patients’ disease,while Th1/Th2 ratio was positively correlated with the severity of patients’ disease.2、In acute stage of cerebral infarction,the level of peripheral inflammation tended to be pro-inflammatory,and the proportion of Th2 and Treg subsets in CD4⁺T cells decreases,while the ratio of Th1/Th2 and Th17/Treg increases.3 、 The neuroprotective effect of distant ischemic posttreatment may be increased by increasing the proportion of Th2 subsets in CD4⁺T cells and decreasing the ratio of Th1/Th2 in peripheral blood of patients.4、Remote ischemic post-treatment may increase the proportion of Th2 subsets in CD4⁺T cells and decrease the ratio of Th1/Th2 in peripheral blood by promoting GATA3 mRNA expression.