Toulza et al. [43] observed that individuals with HAM/TSP had similar IL-10 levels as healthy individuals and that the TGF-β levels were significantly lower compared to the control group; this in turn could result in a decrease in the Treg cell-mediated suppressive function and thus contribute to the exacerbation of inflammation. The gene discussed is TGFB1; the disease is tropical spastic paraparesis.