Characterization of Human Pegivirus Infection in Liver Transplantation Recipients

Approximately 2% of heathy persons are infected with human pegivirus (HPgV). HPgV is transmitted via vertical, sexual, and blood-borne routes. Recently, the association of HPgV infection with the risk of lymphoma was reported. We examined the prevalence of chronic HPgV infection in liver transplantation (LT) recipients and hepatectomy patients and the influence of HPgV infection after LT on clinical and perioperative factors. We enrolled 313 LT recipients and 187 hepatectomy patients who received care at the Kyusyu University Hospital between May 1997 and September 2017. Total RNA was extracted from peripheral blood samples of patients/recipients collected postoperatively. HPgV RNA was measured using real-time polymerase chain reaction (RT-PCR). Of the 313 recipients and 187 patients enrolled in this study, 44 recipients (14.1%) and two patients (1.1%) had HPgV viremia. There was no significant association between HPgV infection and LT outcomes. Interestingly, one recipient was infected with HPgV during the peritransplant period, which was likely transmitted via blood transfusion as HPgV RNA was detected from the blood bag transfused to the recipient during LT. Additionally, HPgV infection induced the upregulation of interferon stimulated gene (ISG) expression in peripheral blood mononuclear cells (PBMCs). LT recipients had higher HPgV viremia compared to hepatectomy patients. Although HPgV infection was not associated with LT-related outcomes, it induced ISG expression in recipients. We examined interferon stimulated gene (ISG) expression in HPgV-positive or negative peripheral blood mononuclear cells (PBMCs) via RNA sequencing analysis.