Expression And Clinical Significance Of Plasma MiR-155 In The Patients With Acute Graft-Versus-Host Disease

BackgroundAcute graft versus host disease?aGVHD?is the most common complication after allogeneic hematopoietic stem cell transplantation?allo-HSCT?,about 40-60%,and most of them require systemic therapy.During the effector phase of inflammation,there is a"cytokine storm,"and30%to 60%patients with?-?aGVHD will become steroid-resistant aGVHD?SR-aGVHD?.miRNAs regulate the proliferation and differentiation of immune cells and maintain the harmony of the immune system.miR-155 is an important member of it.Multiple research have shown that miR-155 not only exists in human cells but also in extracellular fluid.Circulating miRNAs are relatively stable in high temperature,strong acid,and strong alkali environments,and are not easily catabolized by RNase enzymes in plasma.Only in the body's pathological state,its expression level changes.Objectives1.We also intend to probe the levels of plasma miR-155 in patients with aGVHD at different time points before and after transplantation.2.Combined with clinical symptoms,signs,and laboratory examinations of the patients,the clinical significance of plasma miR-155 in aGVHD will be revealed.Material and methodsWe collected 30 samples of peripheral blood from 6 aGVHD patients in our hospital between May 1st,2016 and October 31st,2016 for analyzing.?1?10 ml of peripheral blood of each patient were collected on d0,d7,d14,d21,and d28 after the transplantations of the patients,centrifuged at 1000 rpm for 10 min,and the supernatant was taken as plasma.?2?We used miRNeasy Serum/Plasma kit to extract microRNA from the plasma,and to reversely transcribed microRNA into cDNA,then to detected the expression level of miRNA-155 by PCR amplification,and the last using the 2^-??Ct method to calculate the relative expression of miR-155.?3?We detected the expression levels of TNF-?,IL-4,IL-7 and IL-10 by ELISA methods.?4?Collected the clinical data and laboratory test results of 6 cases of patient.?5?SPSS21.0 statistical software was used to analyze the experimental data and clinical data.p<0.05 was considered statistically significant.Results1.The results qRT-PCR presented that the relative expression level of miR-155 gradually increased after transplantation.The relative expression of miR-155 on d21 and d28 was significantly higher than that in d0,d7,and d14?p<0.05?.In the same patient,miR-155 expression levels in plasma were positively correlated with the clinical classification of aGVHD.2.ELISA results of the patients suggest that their plasma levels of TNF-?and IL-7 gradually increase and IL-4 and IL-10 levels decrease gradually after transplantation.However,the expression levels of various cytokines at different time points have not statistically different significance?p>0.05?.ConclusionsAfter allo-HSCT,the change of miR-155 expression level was earlier than clinical symptoms,and the expression level were positively correlated with the clinical classification of aGVHD.Therefore,miR-155 in plasma may be helpful for the early prediction of aGVHD.