Here, we have cloned infected and uninfected CD4+ and CD8+ cells derived from TSP/HAM patients infected for more than 6 to 26 years, and we have compared them for viral expression, morphological alterations, cell cycle and apoptosis with cells derived from a recent in vitro infection and cloned in the same conditions only 1 month after experimental infection. The gene discussed is CD8A; the disease is tropical spastic paraparesis.