These results indicate that the cause of dysregulation in the proportion of peripheral blood T lymphocyte subsets after stimulation with mycobacterial HSP in patients with SA may also be increased apoptosis of CD4+ T cells and reduced apoptosis of lymphocytes CD8+, causing a decrease in the ratio of CD4+/CD8+ lymphocytes in peripheral blood. Here, CD8A is linked to hereditary spastic paraplegia.