The fine specificity of human T cell lines towards myelin basic protein peptides in southern italian multiple sclerosis patients

We studied the relationship between the HLA specificities associated with m ultiple sclerosis (MS) susceptibility in southern Italy and the reactivity of the human myelin basic protein (hMBP) immunogenic peptides 84-98 and 143 -168, using short-term T-cell lines established from 9 MS patients and from 8 healthy individuals. In our population, DR15 was significantly associate d with MS (34.9% in MS versus 13.7% in healthy controls, P < 0.05). This re sult is in agreement with the association found in northern Europe, but not with data obtained in a population from the island of Sardinia (Italy). In MS patients the frequency of reactive T-cell lines (TCL), tested for fine specificity against the immunodominant hMBP peptides 84-98 and 143-168, was increased for the hMBP 143-168 peptide (P < 0.05) but not for the 84-98 pe ptide. Although this reactivity was higher in DR15(+) MS patients than in D R 15(-) MS patients, it seemed not to be associated with DR15 specificity i n the MS population. Furthermore, there were no significant differences in frequency of reactive TCL to hMBP peptide 84-98 in DR15-positive or DR15-ne gative MS patients. Consequently, it appears that peptide 84-98, considered as a relevant autoantigen, is not implicated in the pathogenesis of MS in our population from southern Italy.