清除B细胞在自身免疫性疾病基础和临床研究中疗效不一，有报道去除B细胞不但达不到治疗目标，反而加重病情。B10细胞已被证实在自身免疫性疾病中，具有负向调控免疫应答作用。 在移植领域B细胞参与移植免疫耐受， 但未见B10细胞诱导免疫耐受。申请者前期小样本试验研究提示去除B细胞后再输注B10细胞可以延长小鼠移植肾的存活。在自身免疫性疾病中增强IL-21/IL-21R信号可以促进B10细胞的扩增和 IL-10的分泌，B10细胞通过IL-10途径调节FoxP3+T细胞表达诱导免疫耐受，但在移植领域中未见报道。 本研究通过小鼠肾移植模型，清除B细胞后再输注不同剂量的B10细胞， 同时注射IL-21或IL-21R.Fc增强或拮抗IL-21/IL-21R信号， 明确B10细胞具有诱导免疫耐受及是否有量效关系，从体内外实验明确IL-21/IL-21R信号对B10细胞的调控作用。

Results were different when B cells were deleted in autoimmune disease model and in clinical practice, some reports showed that it may aggravate disease severity when B cells were deleted. B cells have been recently confirmed to negatively regulate autoimmunity and inflammation in numerous mouse models.Il was confirmed that B cell participated with immune tolerance, but no study showed that B10 cell may stimulate immunological tolerance. It can prolong the graft survival when B10 infusion after B cells deletion in our small sample study. Augmentation of IL-21/IL-21R can promote proliferation of B10 cell and secretion of IL-10 in autoimmune disease. B10 cell induce immune tolerance via IL-10 through expression of FoxP3+T. No report was seen about B10 cell and transplant. Our study was performed by B10 cell infusion after B cells deletion, intraperitoneal injection IL-21 or IL-21R.Fc was given to augmentation or antagonism of IL-21/IL-21R signal, to clarify B10 cells on immune tolerance and regulatory effect by IL-21/IL-21R on B10 cells.