High-dose factor VIII inhibits factor VIII-specific memory B cells in hemophilia A with factor VIII inhibitors.
Blood
; 106(10): 3415-22, 2005 Nov 15.
Article
em En
| MEDLINE
| ID: mdl-16091456
ABSTRACT
Hemophilia A in its severe form is a life-threatening hemorrhagic disease that is caused by mutations in the factor VIII (FVIII) gene (symbol F8). About 25% of patients who receive replacement therapy develop neutralizing antibodies that inhibit the function of substituted FVIII. Long-term application of high doses of FVIII has evolved as an effective therapy to eradicate the antibodies and to induce long-lasting immune tolerance. Little is known, however, about the immunologic mechanisms that cause the down-modulation of anti-FVIII antibodies by high doses of FVIII. We report that high doses of FVIII inhibit the restimulation of FVIII-specific memory B cells and their differentiation into antibody-secreting plasma cells in vitro and in vivo in a murine model of hemophilia A. The inhibition of memory B-cell responses is irreversible and not mediated by FVIII-specific T cells. Furthermore, it seems to involve the activation of caspases. We conclude that the inhibition of FVIII-specific memory B cells might be an early event in the down-modulation of anti-FVIII antibodies in patients with hemophilia A who receive high doses of FVIII.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Plasmócitos
/
Fator VIII
/
Inibidores dos Fatores de Coagulação Sanguínea
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Hemofilia A
/
Memória Imunológica
/
Formação de Anticorpos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article