CD8A and infection: In this mouse, stable T-cell numbers and B-cell-to-T-cell ratios are observed for 8 months after the HSC transplantation, and human T-cell leukemia virus type 1 (HTLV-1)-specific CD8+ cytotoxic T lymphocytes (CTL) and IgG antibodies are induced upon infection with HTLV-1 [55].