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Transient inhibition of interleukin 4 signaling by T cell receptor ligation.

Zhu J, Huang H, Guo L, Stonehouse T, Watson CJ, Hu-Li J, Paul WE - J. Exp. Med. (2000)

Bottom Line: The capacity of various inhibitors to reverse TCR-mediated inhibition of IL-4 signaling suggested that activation of the Ras-mitogen-activated protein kinase pathway and of the calcineurin pathway contribute to desensitizing IL-4R.IL-4 responsiveness returned at about the time ( approximately 12 h) that IL-12-mediated signaling was first observed.Thus, through different mechanisms, neither IL-4R nor IL-12R has any clear advantage in polarizing cells; rather, the availability of cytokine is probably the limiting factor in this process.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.

ABSTRACT
Interleukin (IL)-4 and IL-12 together with T cell receptor (TCR) engagement are crucial for the differentiation of CD4(+) T cells into T helper (Th)2 or Th1 cells, respectively. Although IL-4 receptors (IL-4Rs) but not IL-12Rs are expressed on naive CD4(+) T cells, IL-4 has no apparent advantage over IL-12 in driving naive T cell differentiation when the cells are primed with both IL-4 and IL-12 in vitro. It was found that IL-4-induced phosphorylation of Janus kinases 1 and 3, IL-4R alpha, signal transducer and activator of transcription 6, and insulin receptor substrate 2 was strikingly but transiently inhibited by TCR ligation both in conventional and TCR transgenic T cells. TCR engagement also blocked the expression of an IL-4-inducible gene. Signals induced by other cytokines, including IL-2, IL-6, and interferon alpha, but not by insulin-like growth factor 1, were also blocked by TCR engagement. The capacity of various inhibitors to reverse TCR-mediated inhibition of IL-4 signaling suggested that activation of the Ras-mitogen-activated protein kinase pathway and of the calcineurin pathway contribute to desensitizing IL-4R. IL-4 responsiveness returned at about the time ( approximately 12 h) that IL-12-mediated signaling was first observed. Thus, through different mechanisms, neither IL-4R nor IL-12R has any clear advantage in polarizing cells; rather, the availability of cytokine is probably the limiting factor in this process.

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The cytokine environment early in the course of T cell activation affects Th1/Th2 polarization. 106 naive CD4+ BALB/c T cells were cocultured with 107 irradiated T cell–depleted spleen cells in the presence of anti-CD3 (3 μg /ml), anti-CD28 (3 μg/ml), IL-2 (10 U/ml), and different combinations of anti–IL-4 (11B11, 10 μg/ml), IL-4 (1,000 U/ml), anti–IL-12 (10 μg/ml), and IL-12 (10 ng/ml) for 20 h. Cells were then washed and stimulated with anti-CD3, anti-CD28, IL-2, IL-4, and IL-12 for an additional 3 d. After incubation in IL-2 for an additional 3 d, cells were restimulated with plate-bound anti-CD3 and anti-CD28 for 6 h; monensin (2 μM) was present during the last 4 h. Cells were harvested and stained for intracellular IFN-γ and IL-4 expression. The data are representative of three independent experiments.
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Figure 10: The cytokine environment early in the course of T cell activation affects Th1/Th2 polarization. 106 naive CD4+ BALB/c T cells were cocultured with 107 irradiated T cell–depleted spleen cells in the presence of anti-CD3 (3 μg /ml), anti-CD28 (3 μg/ml), IL-2 (10 U/ml), and different combinations of anti–IL-4 (11B11, 10 μg/ml), IL-4 (1,000 U/ml), anti–IL-12 (10 μg/ml), and IL-12 (10 ng/ml) for 20 h. Cells were then washed and stimulated with anti-CD3, anti-CD28, IL-2, IL-4, and IL-12 for an additional 3 d. After incubation in IL-2 for an additional 3 d, cells were restimulated with plate-bound anti-CD3 and anti-CD28 for 6 h; monensin (2 μM) was present during the last 4 h. Cells were harvested and stained for intracellular IFN-γ and IL-4 expression. The data are representative of three independent experiments.

Mentions: For this observation to be of any significance in the polarization process, it would be important that the early cytokine environment have a substantial role to play in the decision of CD4 T cells to differentiate into Th1 or Th2 cells. To test this, naive CD4+ T cells were primed in the presence of IL-4 or anti–IL-4 and IL-12 or anti–IL-12 during the initial 20 h of culture; all of the cells were then stimulated in the presence of IL-4 and IL-12 for an additional 3 d. After another 3 d in IL-2 medium, the cells were stimulated with immobilized anti-CD3 plus anti-CD28, and the proportion of IL-4 and of IFN-γ–producing cells was measured (Fig. 10). Priming for the initial 20 h in the presence of IL-4 and anti–IL-12 suppresses priming for IFN-γ compared with priming in the presence of anti–IL-4 and anti–IL-12, whereas priming in the presence of IL-12 and anti–IL-4 enhances priming for IFN-γ compared with priming with anti–IL-4 and anti–IL-12. Cells that were primed with both IL-4 and IL-12 were similar to cells primed with anti–IL-4 and anti–IL-12. In a sense, it could be said that IL-12 strikingly reverses the inhibitory effect of IL-4 on early priming for IFN-γ production. This striking effect of transient exposure to different combinations of IL-4 and IL-12 in the first 20 h of culture is even more remarkable when one considers that the cells are insensitive to IL-4 for ∼12 h of this period and to IL-12 for ∼8 h. Thus, even a very brief exposure to a given cytokine environment early in the period of stimulation strikingly effects the polarization of cells despite the fact that they are cultured under identical conditions for the bulk of the priming period. These results strongly suggest that early cytokine-mediated signals received by CD4 T cells play an important role in their decision to polarize into the Th1 or Th2 phenotype. This emphasizes the potential importance of the TCR-mediated desensitization events that limit responsiveness of naive T cells to IL-4 and other type I and type II cytokines.


Transient inhibition of interleukin 4 signaling by T cell receptor ligation.

Zhu J, Huang H, Guo L, Stonehouse T, Watson CJ, Hu-Li J, Paul WE - J. Exp. Med. (2000)

The cytokine environment early in the course of T cell activation affects Th1/Th2 polarization. 106 naive CD4+ BALB/c T cells were cocultured with 107 irradiated T cell–depleted spleen cells in the presence of anti-CD3 (3 μg /ml), anti-CD28 (3 μg/ml), IL-2 (10 U/ml), and different combinations of anti–IL-4 (11B11, 10 μg/ml), IL-4 (1,000 U/ml), anti–IL-12 (10 μg/ml), and IL-12 (10 ng/ml) for 20 h. Cells were then washed and stimulated with anti-CD3, anti-CD28, IL-2, IL-4, and IL-12 for an additional 3 d. After incubation in IL-2 for an additional 3 d, cells were restimulated with plate-bound anti-CD3 and anti-CD28 for 6 h; monensin (2 μM) was present during the last 4 h. Cells were harvested and stained for intracellular IFN-γ and IL-4 expression. The data are representative of three independent experiments.
© Copyright Policy
Related In: Results  -  Collection

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Figure 10: The cytokine environment early in the course of T cell activation affects Th1/Th2 polarization. 106 naive CD4+ BALB/c T cells were cocultured with 107 irradiated T cell–depleted spleen cells in the presence of anti-CD3 (3 μg /ml), anti-CD28 (3 μg/ml), IL-2 (10 U/ml), and different combinations of anti–IL-4 (11B11, 10 μg/ml), IL-4 (1,000 U/ml), anti–IL-12 (10 μg/ml), and IL-12 (10 ng/ml) for 20 h. Cells were then washed and stimulated with anti-CD3, anti-CD28, IL-2, IL-4, and IL-12 for an additional 3 d. After incubation in IL-2 for an additional 3 d, cells were restimulated with plate-bound anti-CD3 and anti-CD28 for 6 h; monensin (2 μM) was present during the last 4 h. Cells were harvested and stained for intracellular IFN-γ and IL-4 expression. The data are representative of three independent experiments.
Mentions: For this observation to be of any significance in the polarization process, it would be important that the early cytokine environment have a substantial role to play in the decision of CD4 T cells to differentiate into Th1 or Th2 cells. To test this, naive CD4+ T cells were primed in the presence of IL-4 or anti–IL-4 and IL-12 or anti–IL-12 during the initial 20 h of culture; all of the cells were then stimulated in the presence of IL-4 and IL-12 for an additional 3 d. After another 3 d in IL-2 medium, the cells were stimulated with immobilized anti-CD3 plus anti-CD28, and the proportion of IL-4 and of IFN-γ–producing cells was measured (Fig. 10). Priming for the initial 20 h in the presence of IL-4 and anti–IL-12 suppresses priming for IFN-γ compared with priming in the presence of anti–IL-4 and anti–IL-12, whereas priming in the presence of IL-12 and anti–IL-4 enhances priming for IFN-γ compared with priming with anti–IL-4 and anti–IL-12. Cells that were primed with both IL-4 and IL-12 were similar to cells primed with anti–IL-4 and anti–IL-12. In a sense, it could be said that IL-12 strikingly reverses the inhibitory effect of IL-4 on early priming for IFN-γ production. This striking effect of transient exposure to different combinations of IL-4 and IL-12 in the first 20 h of culture is even more remarkable when one considers that the cells are insensitive to IL-4 for ∼12 h of this period and to IL-12 for ∼8 h. Thus, even a very brief exposure to a given cytokine environment early in the period of stimulation strikingly effects the polarization of cells despite the fact that they are cultured under identical conditions for the bulk of the priming period. These results strongly suggest that early cytokine-mediated signals received by CD4 T cells play an important role in their decision to polarize into the Th1 or Th2 phenotype. This emphasizes the potential importance of the TCR-mediated desensitization events that limit responsiveness of naive T cells to IL-4 and other type I and type II cytokines.

Bottom Line: The capacity of various inhibitors to reverse TCR-mediated inhibition of IL-4 signaling suggested that activation of the Ras-mitogen-activated protein kinase pathway and of the calcineurin pathway contribute to desensitizing IL-4R.IL-4 responsiveness returned at about the time ( approximately 12 h) that IL-12-mediated signaling was first observed.Thus, through different mechanisms, neither IL-4R nor IL-12R has any clear advantage in polarizing cells; rather, the availability of cytokine is probably the limiting factor in this process.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.

ABSTRACT
Interleukin (IL)-4 and IL-12 together with T cell receptor (TCR) engagement are crucial for the differentiation of CD4(+) T cells into T helper (Th)2 or Th1 cells, respectively. Although IL-4 receptors (IL-4Rs) but not IL-12Rs are expressed on naive CD4(+) T cells, IL-4 has no apparent advantage over IL-12 in driving naive T cell differentiation when the cells are primed with both IL-4 and IL-12 in vitro. It was found that IL-4-induced phosphorylation of Janus kinases 1 and 3, IL-4R alpha, signal transducer and activator of transcription 6, and insulin receptor substrate 2 was strikingly but transiently inhibited by TCR ligation both in conventional and TCR transgenic T cells. TCR engagement also blocked the expression of an IL-4-inducible gene. Signals induced by other cytokines, including IL-2, IL-6, and interferon alpha, but not by insulin-like growth factor 1, were also blocked by TCR engagement. The capacity of various inhibitors to reverse TCR-mediated inhibition of IL-4 signaling suggested that activation of the Ras-mitogen-activated protein kinase pathway and of the calcineurin pathway contribute to desensitizing IL-4R. IL-4 responsiveness returned at about the time ( approximately 12 h) that IL-12-mediated signaling was first observed. Thus, through different mechanisms, neither IL-4R nor IL-12R has any clear advantage in polarizing cells; rather, the availability of cytokine is probably the limiting factor in this process.

Show MeSH
Related in: MedlinePlus