The assessment of the CSF protein profile of HTLV-1-infected individuals also showed that VCAM-1 is differentially expressed in HAM/TSP, and the combination of serum levels of VCAM-1 and SPARC (Secreted protein acidic and rich in cysteine) with the HTLV-1 PVL could predict disease onset in 89.7% of the cases (32). Here, SPARC is linked to tropical spastic paraparesis.