title: Mimicry between HTLV-I and myelin basic protein: no response in HTLV-I-associated myelopathy patients.
abstract: The reactivity to a peptide from the HTLV-I polyprotein (FKLPGLNSR) and a similar sequence from myelin basic protein (MBP) (FKLGGRDSR) was examined in relation to the proposal that mimicry of MBP by HTLV-I could be involved in autoimmune responses in HTLV-I-associated myelopathy (HAM). It was found that rabbit antibodies raised against the HTLV-I peptide recognised both peptides, with a titre of 1/10240 to the HTLV-I peptide and 1/5220 to the MBP peptide. Human sera from HAM patients and a HTLV-I carrier without HAM showed slightly higher responses to the HTLV-I peptide compared to the responses from uninfected human sera. HAM patients had greater responses to the HTLV-I peptide than to the similar MBP peptide and an unrelated bovine MBP peptide. There was no recognition of the peptides by peripheral blood lymphocytes from HAM patients or a HTLV-I carrier without HAM. It was concluded that although cross-reactivity was demonstrated in rabbits and the HTLV-I peptide was recognised by sera from HAM patients, the epitope does not appear to evoke a mimicking response to the similar region in MBP. Hence it is not likely to be involved in the pathogenesis of HAM through molecular mimicry.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015368:Human T-lymphotropic virus 1 / Q000276:immunology*; D006801:Humans; D007114:Immunization; D008969:Molecular Sequence Data; D004676:Myelin Basic Protein / Q000276:immunology*; D015493:Paraparesis, Tropical Spastic / Q000276:immunology*; D011817:Rabbits; D014764:Viral Proteins / Q000276:immunology*
chemical_list: D004676:Myelin Basic Protein; D014764:Viral Proteins