The steering committee for the EULAR/ACR 2019 classification criteria for SLE concluded, based on systematic review and meta-regression analysis of the performance of HEp-2 IIF antibody testing for classifying SLE, that the sensitivity of HEp-2 IIF for ANA detection using a titer of 1:80 is high enough (97.8%) to be considered as an entry criterion [25,26,47]. Here, BTG3 is linked to systemic lupus erythematosus.