# Influence and Role of Regulatory B Cells in Organ Transplantation: The State of the Art, Prospects, and Emerging Insights

## TL;DR

This paper reviews how regulatory B cells may help prevent organ transplant rejection by suppressing harmful immune responses.

## Contribution

It provides a comprehensive summary of the role of regulatory B cells in solid organ transplantation.

## Key findings

- Regulatory B cells (Bregs) have immunosuppressive properties that may promote allograft tolerance.
- Bregs exist in both humans and mice and are part of the B cell compartment.
- B cells are traditionally linked to adaptive immunity but now recognized for regulatory roles in transplantation.

## Abstract

B cells have attracted increasing interest in the field of organ transplantation due to their newly discovered immunoregulatory properties in alloimmune responses. Traditionally, B cells have been primarily associated with adaptive immunity to foreign substances and alloreactive immune response to allografts, differentiating into antibody-producing plasma cells or memory cells upon antigen recognition and T cell collaboration. However, the existence of B cells with regulatory functions (Bregs) in humans has been widely confirmed, highlighting the presence of this subset, which has immunosuppressive properties and which might contribute to allograft tolerance, within the B cell compartment in humans and mice. In this mini review, we summarize all the information available in the published reports about the role of regulatory B cells in solid organ transplantation.