GZMK and juvenile idiopathic arthritis: A total of six separated T cell subtypes had been identified from JIA and cHC by evaluating the expression of CD3E, CD4, CD8A, CCR7, LEF1, SELL, TCF7, CD27, CD28, ICAM2, RGS1, CD69, GZMK, GZMA, CCL5, CD44, FOXP3, KLRB1 (Figures 1D, E), including CD4 Naïve (CD4 Naïve T cells), CD4 TCM (CD4+ central memory T cells), CD8 Naïve (CD8 Naïve T cells), CD8 TEM (CD8+ effector memory T cells), Treg (regulatory T cells) and CCR7+ T (CCR7 positive T cells) (Figures 1D, E).