%A Fähnrich,Anke %A Klein,Sebastian %A Sergé,Arnauld %A Nyhoegen,Christin %A Kombrink,Sabrina %A Möller,Steffen %A Keller,Karsten %A Westermann,Jürgen %A Kalies,Kathrin %D 2018 %J Frontiers in Immunology %C %F %G English %K CD154 costimulation,T cell receptor β repertoire,Humoral Immune Response,sheep red blood cells,Spleen,T:B cell interaction %Q %R 10.3389/fimmu.2018.01019 %W %L %M %P %7 %8 2018-May-17 %9 Original Research %# %! CD154 costimulation affects the T cell receptor repertoire. %* %< %T CD154 Costimulation Shifts the Local T-Cell Receptor Repertoire Not Only During Thymic Selection but Also During Peripheral T-Dependent Humoral Immune Responses %U https://www.frontiersin.org/articles/10.3389/fimmu.2018.01019 %V 9 %0 JOURNAL ARTICLE %@ 1664-3224 %X CD154 is a transmembrane cytokine expressed transiently on activated CD4 T cells upon T-cell receptor (TCR) stimulation that interacts with CD40 on antigen-presenting cells. The signaling via CD154:CD40 is essential for B-cell maturation and germinal center formation and also for the final differentiation of CD4 T cells during T-dependent humoral immune responses. Recent data demonstrate that CD154 is critically involved in the selection of T-cell clones during the negative selection process in the thymus. Whether CD154 signaling influences the TCR repertoire during peripheral T-dependent humoral immune responses has not yet been elucidated. To find out, we used CD154-deficient mice and assessed the global TCRβ repertoire in T-cell zones (TCZ) of spleens by high-throughput sequencing after induction of a Th2 response to the multiepitopic antigen sheep red blood cells. Qualitative and quantitative comparison of the splenic TCZ-specific TCRβ repertoires revealed that CD154 deficiency shifts the distribution of Vβ-Jβ genes after antigen exposure. This data led to the conclusion that costimulation via CD154:CD40 during the interaction of T cells with CD40-matured B cells contributes to the recruitment of T-cell clones into the immune response and thereby shapes the peripheral TCR repertoire.