CD40LG and atherosclerosis: Interestingly, the same group found administration of an agonistic anti-PD1 antibody to Ldlr–/– mice also reduced early atherosclerosis.74 Despite not addressing the impact on TFH cells, which express PD1, they found a significant increase in IgM antibodies, which would fit with the hypothesis that PD1 in TFH favors extrafollicular responses, but further experiments are needed to demonstrate this.