Nonetheless, studies in HAM/TSP patients have reported an increased HTLV-1 proviral load and preferential expansion of HTLV-1 Tax-specific CD8+ T-cells in the cerebrospinal fluid, demonstrating that an additional HTLV-1 reservoir can be established in CD8+ T-cells in vivo [86]. This evidence concerns the gene CD8A and tropical spastic paraparesis.