An antigen-independent contact mechanism as an early step in T cell-proliferative responses to dendritic cells.
J Exp Med
; 170(2): 527-42, 1989 Aug 01.
Article
em En
| MEDLINE
| ID: mdl-2526849
ABSTRACT
Dendritic cells bearing antigen efficiently aggregate and stimulate antigen-specific T cells. We describe an experimental model in which an initial, apparently antigen-independent binding step is followed by ligation of the TCR. The model is the polyclonal response to mAb to the CD3 portion of the TCR complex. Epidermal and thymic dendritic cells utilize low levels of Fc receptors to present the anti-CD3 mAb and induce mitogenesis. Within 3 h of coculture, most of the dendritic cells have formed clusters with the resting T lymphocytes, and these clusters are the site for subsequent DNA synthesis and cell growth. However, the binding of dendritic cells to T cells proceeds as efficiently in the absence of anti-CD3 as in its presence, and anti-FcR mAb does not block. CD3 and Fc receptors are essential for the subsequent mitogenesis response in dendritic-T cell clusters. Because an exogenous ligand for the TCR does not seem to be required for the extensive polyclonal clustering of resting lymphocytes to dendritic cells, we suggest that an antigen-independent mechanism mediates the initial interaction. This clustering seems essential for T cell growth since we do not detect, in two-chamber experiments, soluble lymphocyte-activating factors that originate from dendritic-T cell aggregates and that activate anti-CD3-coated T cells.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Células Dendríticas
/
Ativação Linfocitária
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Receptores de Antígenos de Linfócitos T
/
Receptores Fc
/
Linfócitos T
/
Antígenos de Diferenciação de Linfócitos T
/
Células de Langerhans
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
1989
Tipo de documento:
Article