Fig. 4

Cultured HAM/TSP PBMCs produce exosomes containing HTLV-1 Tax. a HAM 1 and HAM 17 PBMCs were cultured over 5 days and were assessed for HTLV-1 Tax content from isolated exosomes by electrochemical ELISA. b A representative Western blot of HTLV-1 Tax and Actin from nanotrapped (NT80 + 82) exosomes of 7 HAM/TSP patient PBMCs after 5 days culture. Tax compared to Actin (β-actin) levels was quantified for the Western blot and shown in the upper right insert. NS nonspecific band. c An additional Western blot of HTLV-1 Tax, CD63 (two forms: glycosylated (CD63-Gly) and unmodified), and Actin from nanotrapped (NT80 + 82) exosomes of 4 ND and 4 HAM/TSP patient PBMCs after 5 days culture was performed. ND PBMCs were cultured with 100 IU/mL IL-2 while HAM/TSP PBMCs received no exogenous cytokines. Samples were run on a 4–20% Tris–glycine gel, followed by overnight wet transfer to PVDF membranes. C81 whole cell extract (WCE) was utilized as Tax positive control. NS nonspecific band, MW  molecular weight ladder