IFNG and tropical spastic paraparesis: A study from our colleagues [15] demonstrated that serum samples (1:1,024 vs. 1:4096) from asymptomatic and possible/putative HAM/TSP (pHAM) patients with double positive reactivity with MT-2 cells had higher IFN-γ and proviral load, the asymptomatic group with double positive profile also presented lower IL-10, while the double positive pHAM group displayed higher TNF.