KLRB1 and rheumatoid arthritis: We annotated these clusters based on their expression of canonical subset markers, and defined the following clusters of CD8+ T cells in ACPA+ RA and HC blood: Naïve, Memory, TCRgd+, GZMK+, GZMB+GNLY+, GZMB+KIR+ and CCR6+CD161+ (Fig. 2a, b, Supplementary Fig. 4b and Supplementary Table 2).