title: Activation of T lymphocytes in atherosclerotic plaques.
abstract: OBJECTIVE
  To decipher the immunologic mechanisms of plaque maturation and rupture, it is necessary to analyze the phenotypes and distribution of individual lymphocytes that migrate to the plaques, as well as their activation at different stages of plaque formation.
  
  
  RESULTS
  We developed a protocol to isolate plaque-residing immune cells and analyze their status using polychromatic flow cytometry. We found that the composition and phenotype of T lymphocytes in the plaques differs from that in blood. CD4 and, in particular, CD8(+) T cells in plaques are highly activated; the fraction of CD8 T cells coexpressing CD25 and human leukocyte antigen-D related in plaques was 6 times as large as in blood.
  
  
  CONCLUSIONS
  The first flow-cytoanalysis of individual T cells in atherosclerotic plaques indicates that plaques represent a separate immunologic compartment from blood with lymphocytes characterized by a high level of T-cell activation, which is compatible with the presence of antigen(s) that trigger infiltration activation of these cells. The ability to isolate and characterize these cells may lead to the identification of such antigens.
authors.affiliation: Eunice Kennedy-Shriver National Institute of Child Health and Human Development, Program on Physical Biology, Section on Intercellular Interactions, Bethesda, MD, USA.
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Grivel
authors.forename: Oxana
authors.initials: O
authors.lastname: Ivanova
authors.forename: Natalia
authors.initials: N
authors.lastname: Pinegina
authors.forename: Paul S
authors.initials: PS
authors.lastname: Blank
authors.forename: Alexander
authors.initials: A
authors.lastname: Shpektor
authors.forename: Leonid B
authors.initials: LB
authors.lastname: Margolis
authors.forename: Elena
authors.initials: E
authors.lastname: Vasilieva
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006680:HLA Antigens / Q000378:metabolism; D006801:Humans; D016130:Immunophenotyping; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000276:immunology / Q000473:pathology*; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology
chemical_list: D006680:HLA Antigens; D053645:Interleukin-2 Receptor alpha Subunit