title: CD28 T-cell costimulatory molecule expression in pemphigus vulgaris.
abstract: BACKGROUND
  CD28 superfamily of immune costimulatory molecules could play an important role in autotolerance control. CD28 costimulation seems to be necessary for regulatory T cell (Treg) activation and successive suppressive activities involved in autoimmunity protection. This study investigates CD28 expression, especially inducible costimulator fraction, on T lymphocytes in pemphigus vulgaris (PV) patients.
  
  
  METHODS
  CD28 expression on T lymphocytes was assessed in 16 PV patients during acute attack. All patients and 10 healthy control subjects were tested for lymphocyte populations, T-cell subpopulations (T-CD4+, T-CD8+), Treg and CD28 expression on T-cell subpopulations.
  
  
  RESULTS
  T, B and natural killer cells average values in PV patients were close to the control group values. Compared with control group, PV values showed lower Treg (2.2% compared with 4.7%), slightly decreased CD4+ CD28+ T cells (91% compared with 95%), higher CD4+ CD28- T cells (9% compared with 5%), decreased CD8+ CD28+ T cells (57% and 73%, respectively) and significantly enhanced CD8+ CD28- T cells (43% compared with 27%).
  
  
  CONCLUSIONS
  These data suggest that Treg-mediated suppressor T-cell effects could be diminished in PV, together with an abnormal or ineffective subsequent helper T-cell suppression. CD28 high expression on helper T cells and low expression on suppressor T cells are arguments for a potential CD28 role in PV autoimmune response mechanism.
authors.affiliation: Scarlat Longhin Clinical Hospital for Dermatology, Research Center, Bucharest, Romania. alecu.mihail@gmail.com
authors.forename: M
authors.initials: M
authors.lastname: Alecu
authors.forename: C
authors.initials: C
authors.lastname: Ursaciuc
authors.forename: M
authors.initials: M
authors.lastname: Surcel
authors.forename: G
authors.initials: G
authors.lastname: Coman
authors.forename: D
authors.initials: D
authors.lastname: Ciotaru
authors.forename: M
authors.initials: M
authors.lastname: Dobre
mesh_terms: D000328:Adult; D000368:Aged; D018106:CD28 Antigens / Q000276:immunology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010392:Pemphigus / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D018106:CD28 Antigens