Abstract: Kidney transplantation is the preferred treatment method for long⁃term high quality survival in patients with end⁃stage renal  disease,  and  one  of  the  key  research  goals  in  this  area  is  to  find  reliable  ways  to  induce  allograft tolerance in recipients. B cells  have  long  been  thought  to  play  a  critical  role  in  the  adaptive  immune  system  by  secreting antibodies, which are  harmful  to  individuals  with  autoimmune  diseases.  However,  in  recent  years,  several  studies  have shown that not all B cell  subsets  increase  the  immune  response.  Regulatory  B  cells  (Bregs)  may  exert  protective  effects against autoimmune diseases by  secretion  of  inhibitory  cytokines  such  as  IL⁃10,  which  may  help  in  the  discovery  of  new immunotherapies to achieve  immune  tolerance  in  transplantation.  This  article  summarizes  the  discovery,  phenotype,  and immunomodulatory mechanisms  of  Bregs,  and  focuses  on  their  important  role  and  potential  therapeutic  value  in  kidney transplantation immunity.

Key words: regulatory B cells   , kidney transplantation   , immunity    transplant tolerance