THE ASSOCIATION OF ANTIBODIES AGAINST HUMAN T-CELL LYMPHOTROPIC VIRUSTYPE-I (HTLV-I) PX GENE MUTANT PRODUCTS WITH HTLV-I-ASSOCIATED MYELOPATHY TROPICAL SPASTIC PARAPARESIS/

Antibodies specific for the products of the human T cell lymphotropic virus type I (HTLV-I) pX frame-shift mutants were studied by ELISA, Th e serum IgG antibodies to the synthetic peptide corresponding to one n ucleotide insertion at position 7784 were significantly more common in patients with HTLV-I-associated myelopathy/tropical spastic parapares is (HAM/TSP) patients than in HTLV-I carriers who had neither HAM/TSP nor adult T cell leukemia (39% vs, 5%). The seropositivities to the ot her synthetic peptides, which corresponded to the one nucleotide delet ion at position 7475 and the internal deletion of nt 7754-7819 and nt 7853-7936, were rare, A genetic study confirmed the presence of the re sponsible mutation of the pX gene in peripheral blood mononuclear cell s and central nervous system tissue from HTLV-I-infected subjects with and without HAM/TSP. These results suggest that HTLV-I pX frame-shift mutants are expressed in vivo in HTLV-1 carriers; they also induce an tibodies, especially in those with HAM/TSP.