Hepatitis B Virus-Mediated Suppression of Megakaryocyte Differentiation Through Ube4b Upregulation and Modulation of P53 and Erk1/2

Background and aimHepatitis B virus (HBV) infection can lead to thrombocytopenia through its effects on hematopoiesis, although the underlying mechanisms have not been fully elucidated. Platelet production involves multiple stages, including the differentiation of mature megakaryocytes, which plays a pivotal role. In this study, we assessed the variances in megakaryocyte differentiation and maturation after HBV infection and investigated the molecular mechanism involved.MethodsDifferent doses of HBV virus solution extracted from HepAD38 cells were co-cultured with hematopoietic stem cells that had been isolated from fresh, full-term healthy maternal cord blood through magnetic bead sorting. Label-free quantitative proteomics was employed to analyze the differential proteins during the mature megakaryocyte stages pre- and post-HBV infection, with a focus on elucidating their respective molecular mechanisms.ResultsA comparative analysis revealed that HBV impeded the differentiation of fully developed megakaryocytes. Specifically, during the maturation of megakaryocytes, HBV hindered cell DNA polyploidization. Furthermore, its suppressive effect was more pronounced in the later stages of differentiation, consequently leading to impaired platelet production. Proteomic analysis revealed noteworthy disparities in UBE4B protein levels in mature megakaryocytes after HBV infection. Upon transfection with lentivirus and subsequent knockdown of UBE4B in mature megakaryocytes, a noticeable alleviation of HBV's inhibitory impact was observed, accompanied by regulation of p53 and ERK1/2 expression and phosphorylation.ConclusionHBV can upregulate the expression of UBE4B, inhibit the expression and phosphorylation of p53, enhance the expression and phosphorylation of ERK1/2, and suppress the differentiation of mature megakaryocytes, thereby leading to platelet production dysfunction.