Gamma delta T cells are activated by polysaccharide K (PSK) and contribute to the anti-tumor effect of PSK.
Cancer Immunol Immunother
; 62(8): 1335-45, 2013 Aug.
Article
en En
| MEDLINE
| ID: mdl-23685781
ABSTRACT
Polysaccharide K (PSK) is a widely used mushroom extract that has shown anti-tumor and immunomodulatory effects in both preclinical and clinical studies. Therefore, it is important to understand the mechanism of actions of PSK. We recently reported that PSK can activate toll-like receptor 2 and enhances the function of NK cells. The current study was undertaken to study the effect of PSK on gamma delta (γδ) T cells, another important arm of the innate immunity. In vitro experiments using mouse splenocytes showed that γδ T cells produce IFN-γ after treatment with PSK and have up-regulated expression of CD25, CD69, and CD107a. To investigate whether the effect of PSK on γδ T cells is direct or indirect, purified γδ T cells were cultured either alone or together with bone marrow-derived DC in a co-culture or trans-well system and then stimulated with PSK. Results showed that direct cell-to-cell contact between γδ T cells and DC is required for optimal activation of γδ T cells. There was also reciprocal activation of DC by PSK-activated γδ T cells, as demonstrated by higher expression of costimulatory molecules and enhanced production of IL-12 by DC in the presence of γδ T cells. PSK can also co-stimulate γδ T cells with anti-TCR and anti-CD3 stimulation, in the absence of DC. Finally, in vivo treatment with PSK activates γδ T cells among the tumor infiltrating lymphocytes, and depleting γδ T cells during PSK treatment attenuated the anti-tumor effect of PSK. All together, these results demonstrated that γδ T cells are activated by PSK and contribute to the anti-tumor effect of PSK.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Proteoglicanos
/
Linfocitos T
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Receptores de Antígenos de Linfocitos T gamma-delta
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Neoplasias Mamarias Experimentales
Idioma:
En
Revista:
Cancer Immunol Immunother
Asunto de la revista:
ALERGIA E IMUNOLOGIA
/
NEOPLASIAS
/
TERAPEUTICA
Año:
2013
Tipo del documento:
Article
País de afiliación:
Estados Unidos