Serum microRNA181a: Correlates with the intracellular cytokine levels and a potential biomarker for acute graft-versus-host disease.

The aim of this study was to investigate the clinical relevance of lymphocyte-related serum miRNAs to the pathogenesis of acute graft-versus-host disease (aGVHD) and evaluate the predictive and prognosis value of miRNAs. Consecutive patients who received allogeneic peripheral blood stem cell transplantation (allo-PBSCT) in General Hospital of Jinan Military District were enrolled. aGVHD patients were diagnosed and graded clinically, and divided into the training set and the testing set. Blood samples were collected, total RNA was isolated, and RT-PCR was performed for miRNA expression (miR-181a-3p, miR-214-3p and miR-326). Intracellular cytokines levels were assayed by flow cytometry, and the disease specificity assay of miRNAs for aGVHD was detected. A total of 120 patients were admitted. Serum level of miR-181a in aGVHD patients was highly increased and associated with the severity of aGVHD, but not miR-214 and miR-326. Levels of cytokines including IL-2, IL-22, and IL-17a were positively correlated with miR-181a level, while serum IL-13 level was negatively correlated with miR-181a level in aGVHD patients. Moreover, increased miR-181a level was not detected in patients with acute rejection after kidney transplantation or sepsis patients. MiR-181a level was sensitively and specifically increased, especially in severe aGVHD patients. MiR-181a may be a potential biomarker for the identification, diagnosis, and prognosis of aGVHD patients.