CD28 T-cell costimulatory molecule expression in pemphigus vulgaris.
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.
Alecu
M
M
Scarlat Longhin Clinical Hospital for Dermatology, Research Center, Bucharest, Romania. alecu.mihail@gmail.com
Ursaciuc
C
C
Surcel
M
M
Coman
G
G
Ciotaru
D
D
Dobre
M
M
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*
D018106:CD28 Antigens