Moon et al. used scRNAseq and TCR sequencing on CD8+ T cells from blood and found seven distinct clusters of CD8+ T cells (Naïve, Memory, TCRgd+, GZMK+, GZMB+GNLY+, GZMB+KIR+and CCR6+CD161+) where cluster GZMB+KIR+, TCRgd+, and memory were increased, and cluster CCR6+CD161+ were decreased in RA patients compared to healthy controls (110). The gene discussed is CD8A; the disease is rheumatoid arthritis.