Aberrant immunity in the central nervous system in relation to disease progression in HAM/TSP.

The immunological status of the central nervous systems of 19 patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) was distinct from that of 6 asymptomatic HTLV-I carriers. Cross-sectional analysis of the time course of disease-related abnormalities in the cerebrospinal fluid (CSF) showed that activated B cell function was a feature in relatively early HAM/TSP patients in whom duration of the disease was less than 5 to 6 years. During this period many patients experienced notable neurological deterioration. By contrast, an increase in CD8+CD11a+ cytotoxic T lymphocytes along with elevated beta 2-microglobulin levels in the CSF was a consistent finding in early as well as late patients with more than a 10-year history of the illness. In light of the generally progressive course of this disorder, the mode of immunity related to the pathogenesis of HAM/TSP may be different according to the stages of the disease.