CD8A and viral infectious disease: As we were able to observe differences in the relative abundance of EVP surface markers in HTLV-1-infected HAM patients compared to other chronic neurological diseases, particularly in relationship to increased CD8+ EVP signals (Figure 3C), we next investigated if there were differences in the CSF EVP signatures in those additional patients associated with viral infections, including PML (JC polyomavirus), HSV-1 encephalitis, HSV-2 meningitis, Jamestown canyon virus, and HIV-1 (Table 1).