A transendocytosis model of CTLA-4 function predicts its suppressive behavior on regulatory T cells.
J Immunol
; 194(5): 2148-59, 2015 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-25632005
ABSTRACT
Manipulation of the CD28/CTLA-4 pathway is at the heart of a number of immunomodulatory approaches used in both autoimmunity and cancer. Although it is clear that CTLA-4 is a critical regulator of T cell responses, the immunological contexts in which CTLA-4 controls immune responses are not well defined. In this study, we show that whereas CD80/CD86-dependent activation of resting human T cells caused extensive T cell proliferation and robust CTLA-4 expression, in this context CTLA-4 blocking Abs had no impact on the response. In contrast, in settings where CTLA-4(+) cells were present as "regulators," inhibition of resting T cell responses was dependent on CTLA-4 expression and specifically related to the number of APC. At low numbers of APC or low levels of ligand, CTLA-4-dependent suppression was highly effective whereas at higher APC numbers or high levels of ligand, inhibition was lost. Accordingly, the degree of suppression correlated with the level of CD86 expression remaining on the APC. These data reveal clear rules for the inhibitory function of CTLA-4 on regulatory T cells, which are predicted by its ability to remove ligands from APC.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Células Dendríticas
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Linfócitos T Reguladores
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Modelos Imunológicos
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Anticorpos
Tipo de estudo:
Prognostic_studies
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Risk_factors_studies
Limite:
Animals
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Humans
Idioma:
En
Revista:
J Immunol
Ano de publicação:
2015
Tipo de documento:
Article