CXCL9 and tropical spastic paraparesis: Elevated CSF and serum levels of CXCL9 and CXCL10, compared to carriers, alongside low levels of CCL2 are considered as pivotal markers of HAM/TSP (Guerreiro et al., 2006; Sato et al., 2013; Starling et al., 2015; Lima et al., 2017).