Regulatory B lymphocytes and mechanisms of their action

Regulatory B lymphocytes (Bregs) represent a small population of B cells which participate in immunomodulations and in suppression of immune responses. These cells can regulate the immune system by different mechanisms, but the main mechanism of their action is a production of anti-inflammatory cytokine interleukin 10. The regulatory effects of Bregs were described in various models of inflammation, autoimmune diseases, transplantation reactions and in anti-tumor immunity. During autoimmune diseases Bregs function as important regulatory elements which can support remission or repression of the disease. Bregs have also important therapeutic potential in transplantation immunity where they can suppress rejection reactions. However, Bregs can disturb immune surveillance due to their immunosuppressive influence and thus they can attenuate anti-tumor immunity. Therefore, the aim of this thesis is to summarize the recent knowledge about Bregs. The thesis is focused on the mechanisms of Breg action in regulation of immune responses. The imunoregulatory effects of Bregs are described in various models of autoimmune diseases, transplantation immunity and anti-tumor immunity. The recognition of mechanisms of Breg action may have a great impact for their potential use in a clinical setting