Profiling the pattern of human TRB/IGH-CDR3 repertoire in liver transplantation patients via high-throughput sequencing analysis

Immune processes in liver transplantation remain poorly understood. Acute allograft rejection in liver transplantation is a kind of T cell–mediated inflammatory disease accompanied by inflammatory cell infiltration. However, the effect of acute allograft rejection on the immunological characteristics of TCRs in peripheral blood mononuclear cell is unknown. In this study, we characterized the pattern of the human T cell receptor beta chain (TRB) and immunoglobulin heavy chain (IGH) complementarity-determining region 3 (CDR3) repertoires via high-throughput sequencing in 11 acute allograft rejection (AG) cases, 23 patients with stable allograft liver function (ST) who had liver transplantation performed and 20 healthy controls (HC). The diversity of TRB-CDR3 was significantly reduced in the AG group compared with the ST group and healthy controls (HC). The CDR3 and N-addition length distribution were not significantly different between the AG and ST groups. However, N-addition length distribution was significantly changed compared to HC. It seemed that AG used more short N-additions and healthy people used more long N-additions in TRB-CDR3 repertoire. Our findings suggested that the TRB-CDR3 region of AG had distinctive V gene use compared with that of HC. The characteristics of ST seemed to be in between those of AG and HC although the difference is not significant. Cluster analysis showed that the TRB repertoire could not effectively distinguish AG from ST. This research might give to a better understanding of the immune process of liver transplantation.