调节性B细胞在移植免疫耐受中的研究进展

Research progress of regulatory B cells in transplantation immune tolerance

B细胞主要通过产生抗原特异性抗体,辅助诱导CD4^(+)T细胞活化发挥正向免疫调节作用。然而近年动物试验研究表明B细胞亦可负向调节免疫反应,这类B细胞被称为调节性B细胞(Bregs)。Bregs是新近发现的一类具有免疫抑制功能的B细胞亚群,已被证实在自身免疫性疾病、恶性肿瘤、感染性疾病和器官移植中扮演重要角色。通过促进调节性T细胞(Tregs)发育,抑制CD4^(+)/CD8^(+)T细胞分化等途径,Bregs可显著诱导移植物免疫耐受反应。与Tregs有标志性的转录因子Foxp3不同,Bregs没有标志性的转录因子,他们共同的特征是产生抑制性细胞因子白介素(IL)-10,有些还分泌IL-35和转化生长因子(TGF)-β。鉴于调节性免疫细胞网络是目前移植免疫领域研究热点内容之一,本综述将从Bregs起源、发育、分化、表型、生理学功能等方面探讨其在诱导移植免疫耐受中的作用,旨在为诱导移植免疫耐受提供新的研究角度。

B cells play a positive immunomodulatory role mainly by producing antigen-specific antibodies and assisting in inducing the activation of CD4^(+)T cells.However,recent animal experiments have shown that B cells can also negatively regulate immune response,named as regulatory B cells(Bregs).Bregs is a newly discovered subgroup of B cells with immunosuppressive function and has been proven to play an important role in autoimmune diseases,malignancies,infectious diseases,and organ transplantation.By promoting regulatory T cell(Tregs)development and inhibiting CD4^(+)/CD8^(+)T cell differentiation,Bregs can significantly induce immune tolerance responses in grafts.Unlike Tregs with a hallmark transcription factor Foxp3,but Bregs share the common features of producing the suppressor cytokine Interleukin(IL)-10 and some also secreting IL-35 and transforming growth factor-β(TGF-β).Given that the regulatory immune cell network is one of the hot research elements in the field of transplantation immunity,this review will explore the role of Bregs in the induction of transplantation immune tolerance in terms of its origin,development,differentiation,phenotype,and physiological functions to provide a new research perspective for the induction of transplantation immune tolerance.