R. Kubota et al., HTLV-I PROVIRAL DNA AMOUNT CORRELATES WITH INFILTRATING CD4-CORD FROMPATIENTS WITH HTLV-I-ASSOCIATED MYELOPATHY( LYMPHOCYTES IN THE SPINAL), Journal of neuroimmunology, 53(1), 1994, pp. 23-29
A quantitative method utilizing polymerase chain reaction was employed
to evaluate the amount of human T-cell leukemia virus type I (HTLV-I)
proviral DNA in the affected spinal cords from patients with HTLV-I-a
ssociated myelopathy/tropical spastic paraparesis (HAM/TSP). Central n
ervous system (CNS) tissues were obtained at post-mortem from five pat
ients with HAM/TSP, who vary in the duration of illness from 2.5-10 ye
ars, and one patient with adult T-cell leukemia (ATL), who had leukemi
c cell infiltration in the CNS. The presence of HTLV-I pX and pol sequ
ences in the CNS tissues were demonstrated in ail patients examined. I
n HAM/TSP, the proviral DNA quantified in the thoracic cord was 0.002-
2 copies per 100 tissue cells, and that in the peripheral blood mononu
clear cells (PBMC) was 2-8 copies per 100 PBMC. The proviral DNA amoun
t in the thoracic cord of the patient with ATL was 0.4 copies per 100
tissue cells. An apparent propensity for the amount of integrated HTLV
-I in the thoracic cord to decrease with the disease duration in patie
nts with HAM/TSP was observed. The decline in HTLV-I proviral DNA amou
nt in the thoracic cord lesions was paralleled with the alteration of
proportion of CD4(+) T lymphocytes in patients with HAM/TSP. These fin
dings suggest that preferential virus reservoir may be infiltrating CD
4(+) T lymphocytes in the spinal cord lesions of patients with HAM/TSP
, and HTLV-I infection in the CNS of patients is declining with the di
sease duration in spite of the chronic course of neurological manifest
ations at least in some patients with HAM/TSP.