484회

TITLE : Regulation of mast cells and allergic responses by regulatory B cells

SPEAKER : 최 완 수 교수 (건국대학교 의학전문대학원)

Education

Research Experiences

ABSTRACT

It was previously suggested that IL-10-producing CD5⁺ B cells, also called regulatory B cells, are potentially associated with regulation of anaphylaxis and food allergies, but the mechanisms are largely unknown. In this study, we investigated the action and mechanisms by which IL-10-producing CD5⁺ B cells suppress allergic responses in vitro and in vivo. CD5⁺ B cells suppressed IgE/Ag-mediated activation of mast cells and the allergic responses in an IL-10-dependent manner. The suppressive effect of CD5⁺ B cells on mast cells was dependent on direct cell contact through CD40 on CD5⁺ B cells and CD40 ligand (CD40L) on mast cells. Of interest, the production of IL-10 from CD5⁺ B cells was enhanced by the direct contact of mast cells. Mechanistically, IL-10-producing CD5⁺ B cells inhibited activation of Syk in mast cells through diminished expression of Fyn and Fgr. IL-10-producing CD5⁺ B cells have a previously unrecognized role in negatively regulating mast cells and IgE-mediated allergic responses. These findings reveal that IL-10-producing CD5⁺ B cells may have relevance in the treatment of allergic disease in humans.