CD40-CD40 ligand interaction between dendritic cells and CD8+ T cells is needed to stimulate maximal T cell responses in the absence of CD4+ T cell help.
J Immunol
; 178(5): 2844-52, 2007 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-17312128
Stimulation of CD40 on APCs through CD40L expressed on helper CD4+ T cells activates and "licenses" the APCs to prime CD8+ T cell responses. Although other stimuli, such as TLR agonists, can also activate APCs, it is unclear to what extent they can replace the signals provided by CD40-CD40L interactions. In this study, we used an adoptive transfer system to re-examine the role of CD40 in the priming of naive CD8+ T cells. We find an approximately 50% reduction in expansion and cytokine production in TCR-transgenic T cells in the absence of CD40 on all APCs, and on dendritic cells in particular. Moreover, CD40-deficient and CD40L-deficient mice fail to develop endogenous CTL responses after immunization. Surprisingly, the role for CD40 and CD40L are observed even in the absence of CD4+ T cells; in this situation, the CD8+ T cell itself provides CD40L. Furthermore, we show that although TLR stimulation improves T cell responses, it cannot fully substitute for CD40. Altogether, these results reveal a direct and unique role for CD40L on CD8+ T cells interacting with CD40 on APCs that affects the magnitude and quality of CD8+ T cell responses.
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Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Células Dendríticas
/
Ativação Linfocitária
/
Comunicação Celular
/
Linfócitos T CD8-Positivos
/
Antígenos CD40
/
Ligante de CD40
Limite:
Animals
Idioma:
En
Revista:
J Immunol
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Estados Unidos