The proviral load and cytokine profile were also analyzed for HTLV-1 HAM/TSP, one of the most serious clinical manifestations from the HTLV-1 infection, and although this group displayed lower TNF and IL-10 they had higher proviral load, with the authors concluding that MT-2 IgG1 reactivity profile correlates with proviral load, with significant positive association. Here, TNF is linked to tropical spastic paraparesis.