Expansion of CD80
lymphocytes upon in vitro culture of PBMCs of HAM/TSP patients but not in HTLV-1 carriers and MS patients. CD80 and CD86 expression in PBMCs was quantified before (ex vivo) and after 48 h of in vitro culture by flow cytometry. (A) Significant in vitro expansion of CD80+ cells in HAM/TSP patients (***p = 0.0001, n = 12) and HCs (*p = 0.049, n = 6). (B) Significant in vitro expansion of CD86+ cells in HAM/TSP patients only (**p = 0.0054; paired t test).