title: Isolation of CD45RO+, memory T cells recognizing proteolipid protein from neurologically normal subjects.
abstract: Previous studies provide evidence for in vivo activation of MBP-reactive T cells in subjects with multiple sclerosis. In general, in vivo activation occurs less frequently in healthy control subjects. In the current study we examined the T cell response to proteolipid protein in PBMC isolated from 9 control subjects. We used CD45 isotypes as markers for memory and naïve T cells to assess in vivo activation of CD4+ T cells reactive with PLP. In contrast to the results obtained using MBP, we found that approximately 50% of PLP-reactive T cells were derived from the CD45RO+ memory subpopulation of T cells isolated from these control subjects. These results indicate that some myelin-reactive T cells have undergone activation in vivo in neurologically intact individuals. This suggests that immunoregulatory mechanisms may be present that prevent overt disease in spite of in vivo activation of PLP-reactive T cells.
authors.affiliation: Department of Neurology, Neurovirology Research 151B, V.A. Medical Center, University of Utah, 500 Foothill Drive, Salt Lake City, UT 84148, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Burns
authors.forename: B D
authors.initials: BD
authors.lastname: Bartholomew
authors.forename: S T
authors.initials: ST
authors.lastname: Lobo
mesh_terms: D000328:Adult; D015551:Autoimmunity; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D017493:Leukocyte Common Antigens / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D004676:Myelin Basic Protein / Q000276:immunology; D018991:Myelin Proteolipid Protein / Q000276:immunology*; D012016:Reference Values; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D004676:Myelin Basic Protein; D018991:Myelin Proteolipid Protein; D017493:Leukocyte Common Antigens