Continued Bcl6 expression prevents the transdifferentiation of established Tfh cells into Th1 cells during acute viral infection

By using a temporally-controlled system for the ablation of Bcl6 and Cxcr5 speficially in CD4 T cells, the requirements of both factors for the maintenance of Tfh cells were investigated Cd4-CreERT2+ mice without floxed alleles were used as controls in all experiments. Bcl6 ablation in SMARTA cells in LCMV infection: iBcl6KO (n=5), Ctrls (n=3) Cxcr5 ablation in SMARTA cells in LCMV infection: iCxcr5KO (Tfh: n=4, Th1: n=4), Ctels (Tfh: n=3; Th1: n=5) Cxcr5 ablation in NP-KLH immunization: iCxcr5KO (Tfh: n=6), Ctrls (Tfh: n=4; non-Tfh: n=4)