CD8A and juvenile idiopathic arthritis: Within HLA-B27- JIA and HLA-B27+ JIA datasets, there were 7,891 and 13,093 T cells, respectively, divided into six subtypes (CD4 Naïve, CD4 TCM, CD8 Naïve, CD8 TEM, Treg, and CCR7+ T cell) (Figure 3A).