Among BM sample, the level of HLA-DR+CD8+TCM cells significantly decreased in all groups and CD8+TEMRA cells from TKI-F patients exhibited increased level of TIGIT and CD8+ tissue-residual T cells (TRM) from DN-CML patients expressed a higher level of PD-1 and TIGIT. The gene discussed is CD8A; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.