Analysis of DNA methylation with 5-Azac induced immune hyporesponsiveness following acute graft-versus-host disease / 天津医药

ABSTRACT

Objective To analyse the change of DNA methylation with 5-Azac injection in acute graft-versus-host dis- ease (aGVHD) mouse model, which received allogeneic bone marrow transplantation, and explore the immunomodulatory ef-fects of 5-Azac. Methods Male C57BL/6 (H-2b)and female BALB/c (H-2d) mice were selected as donor and recipient of complete allotransplantation. BABL/c mice were divided into two groups, transplantation control group and 5-Azac experi-mental group. At 1-7, 14, 21 and 28-day after transplantion, 5-Azac 0.25 mg/kg (0.3 mL/time) was injected by tail vein in experimental group, while the control group were injected with sterile water 0.3 mL/time. Peripheral blood DNA samples were collected from three control mice and three experimental mice, then mixed with equal amount respectively. The MeDIP-seq method was selected to detect methylation changes in mice, and the differential DNA methylation in the biological path-ways was analyzed. Results The survival time was prolonged, and the rejection reaction was decreased in 5-Azac experi-mental group, which suggested immune hyporesponsiveness post aGVHD. The MeDIP-seq result showed that 369 different DNA methylation located in the promoter regions, including 239 up-regulated genes and 130 down-regulated genes. There were 184 differential DNA methylation genes located in the exon regions, including 113 up-regulated genes and 71 down-regulated genes. Differential DNA methylation genes involved in 10 immunological signaling pathways, respectively. Among them, TGF-β, GSK-3β, SYK, PI3K, NFAT, CD28 andα4β7 were closely related to the development of aGVHD. Conclu-sion 5-Azac can effectively induce immune hyporesponsiveness post aGVHD by changing the gene methylation status.