Activated CD4+ T cells enter the splenic T-cell zone and induce autoantibody-producing germinal centers through bystander activation.
Eur J Immunol
; 44(1): 93-102, 2014 Jan.
Article
em En
| MEDLINE
| ID: mdl-24114675
ABSTRACT
CD4(+) T (helper) cells migrate in huge numbers through lymphoid organs. However, little is known about traffic routes and kinetics of CD4(+) T-cell subsets within different organ compartments. Such information is important because there are indications that CD4(+) T cells may influence the function of microenvironments depending on their developmental stage. Therefore, we investigated the migration of resting (naïve), activated, and recently activated (memory) CD4(+) T cells through the different compartments of the spleen. Resting and recently activated CD4(+) T cells were separated from thoracic duct lymph and activated CD4(+) T cells were generated in vitro by cross-linking the T-cell receptor and CD28. The present study shows that all three CD4(+) T-cell subsets selectively accumulate in the T-cell zone of the spleen. However, only activated T cells induce the formation of germinal centers (GCs) and autoantibodies in rats and mice. Our results suggest that in a two-step process they first activate B cells independent of the T-cell receptor repertoire and CD40 ligand (CD154) expression. The activated B cells then form GCs whereby CD154-dependent T-cell help is needed. Thus, activated T cells may contribute to the development of autoimmune diseases by activating autoreactive B cells in an Ag-independent manner.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Autoanticorpos
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Baço
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Linfócitos T CD4-Positivos
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Subpopulações de Linfócitos T
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Centro Germinativo
Limite:
Animals
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article