We observed an increase in ICOS+ programmed cell death 1–positive (PD-1+) activated cTfh cells across all 3 cTfh subsets in SLE, along with enhanced B cell activation and differentiation into antibody-secreting cells, particularly by SLE cTfh17 cells compared with healthy controls (HCs). Here, PDCD1 is linked to systemic lupus erythematosus.