Abnormal T cell receptor V gene usage in myasthenia gravis: prevalence and characterization of expanded T cell populations.
Clin Exp Immunol
; 113(3): 456-64, 1998 Sep.
Article
en En
| MEDLINE
| ID: mdl-9737677
The usage of T cell receptor (TCR) Valpha/Vbeta chains on cells from 38 patients with myasthenia gravis (MG) was determined by flow cytometry. There was a decreased number of cells expressing Vbeta2 in CD8+ and Vbeta3 in CD4+ cells in patients compared with healthy individuals. Abnormal expansions of T cells using particular TCR Valpha/Vbeta gene products were found in 18/38 patients. A significantly higher usage of Vbeta13 was observed but there was no restriction with regard to other TCR Valpha/Vbeta. Expanded cells belonging to both CD4+ and CD8+ were present in MG patients while restricted to the CD8+ population in healthy individuals. To elucidate the role of the expanded populations, we studied characteristics of the expanded and non-expanded T cells from MG patients who had persistent T cell expansions over more than 2 years. The cells were analysed with regard to phenotype, cytokine secretion, cytokine mRNA expression and reactivity with the autoantigen, the acetylcholine receptor. The characteristics of the expanded populations in MG clearly differed from those found in healthy individuals. More cells in the CD4+ expanded populations expressed HLA-DR and there was also a tendency for higher expression of CD25, CD28 and CD57. The number of cells spontaneously secreting cytokines was higher in the expanded populations. A dominant Th1-type cytokine secretion and mRNA expression was noted. Autoantigen-reactive CD4+ T cells were largely restricted to the expanded populations.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Linfocitos T
/
Receptores de Antígenos de Linfocitos T alfa-beta
/
Miastenia Gravis
Tipo de estudio:
Prevalence_studies
/
Risk_factors_studies
Límite:
Adult
/
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Clin Exp Immunol
Año:
1998
Tipo del documento:
Article
País de afiliación:
Suecia
Pais de publicación:
Reino Unido