Figure 2. In vivo-generated Th1 and T_FH cells possess and mobilize pCD40L.

A, Generation of antigen-specific Th1 cells. LCMV-glycoprotein-specific, TCR-transgenic SMARTA CD4⁺ T cells were recovered from LCMV-infected mice on day 8 post-infection. B, Gating strategy for SMARTA cells (Vα2⁺, Vβ8.3⁺). C, Mobilization of pCD40L by SMARTA cells in response to PMA plus ionomycin or the LCMV peptide gp67-pulsed APC. D, Polyclonal Th1 and T_FH cells. Spleen cells were obtained from LCMV-infected mice on day 12 post-infection. E, Gating strategy for T_FH (CD4⁺CD44^hiCXCR5^hiPD-1^hi) and Th1 (CD4⁺CD44^hiCXCR5^lowPD-1^low) cells. F, Mobilization of pCD40L by T_FH and Th1 cells in response to PMA plus ionomycin. Data are representative of two independent experiments.