CD4 and rheumatoid arthritis: To determine whether IKAROS is involved in the differential regulation of ORAI3 transcription in RA and PsA compared to normal naive CD4+ T cells, we examined chromatin accessibility and transcription of the IKAROS-encoding gene IKZF1 using ATAC-sequencing data of isolated naive and central memory (CM) CD4+ T cells from nine HCs, 15 to 17 patients with RA, and 10 PsA patients.