AUTHOR=Yamano Tomoyoshi , Steinert Madlen , Klein Ludger 

TITLE=Thymic B Cells and Central T Cell Tolerance

JOURNAL=Frontiers in Immunology

VOLUME=Volume 6 - 2015

YEAR=2015

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2015.00376

DOI=10.3389/fimmu.2015.00376

ISSN=1664-3224

ABSTRACT=Central T cell tolerance is believed to be mainly induced by thymic dendritic cells and medullary thymic epithelial cells. The thymus also harbors substantial numbers of B cells. These may arise though intrathymic B lymphopoiesis or immigration from the bloodstream. Importantly, and in contrast to resting ‘mainstream’ B cells in the periphery, thymic B cells display elevated levels of MHC class II and constitutively express CD80. Arguably their most unexpected feature is the expression of Aire. These unique features of thymic B cells result from a licensing process that involves cross-talk with CD4 single-positive T cells and CD40 signaling. Together, these recent findings suggest that B cells play a more prominent role as thymic APCs than previously appreciated.