CD28 T-cell costimulatory molecule expression in pemphigus vulgaris

• Published in: Journal of the European Academy of Dermatology and Venereology Vol. 23; no. 3; pp. 288 - 291
• Main Authors: Alecu, M, Ursaciuc, C, Surcel, M, Coman, G, Ciotaru, D, Dobre, M
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.03.2009
• Subjects: Adult; Aged; autoimmune diseases; Case-Control Studies; CD28 Antigens - immunology; CD28 molecule; Female; Humans; Male; Middle Aged; Pemphigus - immunology; pemphigus vulgaris; regulatory T cells; T-Lymphocytes - immunology
• ISSN: 0926-9959; 1468-3083; 1468-3083
• DOI: 10.1111/j.1468-3083.2008.03035.x

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. Conflicts of interest None declared