IL6 and tropical spastic paraparesis: Elevated levels of proinflammatory cytokines (IL-6, IFN-γ, IL-15, IL-1β, TNF-α and IL-12) have been detected in the serum and cerebrospinal fluid (CSF) of patients with HAM/TSP, corroborating the link between HAM/STP development and dysregulated inflammation [18], [19].