In ADC specimens (compared with SCC specimens), we observed significantly higher densities of CD3 + CD8 + cytotoxic T-cells, CD3 + CD45RO + memory T-cells, CD3 + CD8 + CD45RO + cytotoxic memory T-cells, CD3 + IDO-1 + T-cells, and CD3 + TIM3 + cells. The gene discussed is IDO1; the disease is AIDS dementia complex.