TPH1 and systemic lupus erythematosus: To evaluate whether clonal expansion of Tph and Tfh cells occurs prior to the full clinical manifestation of SLE, we evaluated CD4 T cells longitudinally from a set of patients who did not initially meet the ACR/EULAR 2019 classification criteria for SLE, but scored 4–9 points, and were considered clinically at high risk of developing SLE.