An optimized method to differentiate mouse follicular helper T cells in vitro

摘要

Upon priming,naive CD4+helper T(Th)cells differentiate into distinct subsets with specialized functions.The differentiation of Th subsets is driven not only by signals from the T cell receptor(TCR)and costimulatory receptors but is also critically dependent on the specific cytokine milieu.By mimicking such conditions,robust methods have been developed for the in vitro differentiation of type 1 and type 2 Th(Th1 and Th2)cells,and more recently,IL-17-producing Th(Th17)cells and regulatory T(Treg)cells,1 which greatly support the research and applications of these Th subsets.Follicular helper T(Tfh)cells represent another Th subset that specializes in supporting the germinal center(GC)response and regulating the generation of memory B cells and long-lived plasma cells.2 However,current methods for in vitro Tfh differentiation are not optimal.Even in the best practice,only 20%of polarized cells showed the expression of CXCR5,the key Tfh functional marker.3 Here,we report an optimized in vitro differentiation method that generates 50–75%CXCR5+cells with enhanced B cell helper function.We demonstrate that the priming of antigen-presenting cells(APCs)by lipopolysaccharide(LPS)and the increase of the APC:T cell ratio were key to efficiently generating Tfh cells in vitro.