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Tuning sensitivity to IL-4 and IL-13: differential expression of IL-4Ralpha, IL-13Ralpha1, and gammac regulates relative cytokine sensitivity.

Junttila IS, Mizukami K, Dickensheets H, Meier-Schellersheim M, Yamane H, Donnelly RP, Paul WE - J. Exp. Med. (2008)

Bottom Line: In contrast, IL-13 stimulated greater responses than IL-4 in fibroblasts.The differential expression of IL-4Ralpha, IL-13Ralpha1, and gammac accounted for the distinct IL-4-IL-13 sensitivities of the various cell types.These findings provide an explanation for IL-13's principal function as an "effector" cytokine and IL-4's principal role as an "immunoregulatory" cytokine.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA. junttilai@niaid.nih.gov

ABSTRACT
Interleukin (IL)-4 and -13 are related cytokines sharing functional receptors. IL-4 signals through the type I (IL-4Ralpha/common gamma-chain [gammac]) and the type II (IL-4Ralpha/-13Ralpha1) IL-4 receptors, whereas IL-13 utilizes only the type II receptor. In this study, we show that mouse bone marrow-derived macrophages and human and mouse monocytes showed a much greater sensitivity to IL-4 than to IL-13. Lack of functional gammac made these cells poorly responsive to IL-4, while retaining full responsiveness to IL-13. In mouse peritoneal macrophages, IL-4 potency exceeds that of IL-13, but lack of gammac had only a modest effect on IL-4 signaling. In contrast, IL-13 stimulated greater responses than IL-4 in fibroblasts. Using levels of receptor chain expression and known binding affinities, we modeled the assemblage of functional type I and II receptor complexes. The differential expression of IL-4Ralpha, IL-13Ralpha1, and gammac accounted for the distinct IL-4-IL-13 sensitivities of the various cell types. These findings provide an explanation for IL-13's principal function as an "effector" cytokine and IL-4's principal role as an "immunoregulatory" cytokine.

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Expression of type I and II IL-4 receptor complex chains on BMDMs and PMs. (A) γc and IL-4Rα chain expression in WT and γc−/− BMDMs and PMs. Cells were washed twice and stained for 20 min at 4°C, washed again twice, and subjected to flow cytometric analysis. Representative stainings for each cell type are shown. (B) Quantitated data from the cell surface stainings of 7 (BMDMs) or 5 (PMs) independent experiments are shown. The analysis was performed as in Fig. 5 F. (C) IL-13 receptor expression in BMDMs and PMs. 2 × 105 BMDMs and PMs were lysed, 150 μg of total cell lysate was separated on PAGE gel, followed by Western blotting and immunostaining against IL-13Rα1. Equal loading and transfer was verified with Ponceau S staining.
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fig6: Expression of type I and II IL-4 receptor complex chains on BMDMs and PMs. (A) γc and IL-4Rα chain expression in WT and γc−/− BMDMs and PMs. Cells were washed twice and stained for 20 min at 4°C, washed again twice, and subjected to flow cytometric analysis. Representative stainings for each cell type are shown. (B) Quantitated data from the cell surface stainings of 7 (BMDMs) or 5 (PMs) independent experiments are shown. The analysis was performed as in Fig. 5 F. (C) IL-13 receptor expression in BMDMs and PMs. 2 × 105 BMDMs and PMs were lysed, 150 μg of total cell lysate was separated on PAGE gel, followed by Western blotting and immunostaining against IL-13Rα1. Equal loading and transfer was verified with Ponceau S staining.

Mentions: Measurements of binding properties of the components of the type I and II receptors and recent structural characterization of type I and II IL-4 receptors (28) suggested that relative receptor chain expression might provide a mechanism to regulate the relative potency of IL-4 and -13. Indeed, the analysis of receptor chain expression in the human monocyte subpopulations supports this idea (Fig. 5 F). We examined the expression of different receptor chains on BMDMs and PMs by flow cytometry, and representative stainings are shown in Fig. 6 A. We quantitated the data from independent stainings in Fig. 6 B. γc expression was detected clearly on both BMDMs and PMs, with fourfold higher expression on PMs. IL-4Rα expression was 2.6-fold higher on PMs than on BMDMs (Fig. 6 B).


Tuning sensitivity to IL-4 and IL-13: differential expression of IL-4Ralpha, IL-13Ralpha1, and gammac regulates relative cytokine sensitivity.

Junttila IS, Mizukami K, Dickensheets H, Meier-Schellersheim M, Yamane H, Donnelly RP, Paul WE - J. Exp. Med. (2008)

Expression of type I and II IL-4 receptor complex chains on BMDMs and PMs. (A) γc and IL-4Rα chain expression in WT and γc−/− BMDMs and PMs. Cells were washed twice and stained for 20 min at 4°C, washed again twice, and subjected to flow cytometric analysis. Representative stainings for each cell type are shown. (B) Quantitated data from the cell surface stainings of 7 (BMDMs) or 5 (PMs) independent experiments are shown. The analysis was performed as in Fig. 5 F. (C) IL-13 receptor expression in BMDMs and PMs. 2 × 105 BMDMs and PMs were lysed, 150 μg of total cell lysate was separated on PAGE gel, followed by Western blotting and immunostaining against IL-13Rα1. Equal loading and transfer was verified with Ponceau S staining.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2571934&req=5

fig6: Expression of type I and II IL-4 receptor complex chains on BMDMs and PMs. (A) γc and IL-4Rα chain expression in WT and γc−/− BMDMs and PMs. Cells were washed twice and stained for 20 min at 4°C, washed again twice, and subjected to flow cytometric analysis. Representative stainings for each cell type are shown. (B) Quantitated data from the cell surface stainings of 7 (BMDMs) or 5 (PMs) independent experiments are shown. The analysis was performed as in Fig. 5 F. (C) IL-13 receptor expression in BMDMs and PMs. 2 × 105 BMDMs and PMs were lysed, 150 μg of total cell lysate was separated on PAGE gel, followed by Western blotting and immunostaining against IL-13Rα1. Equal loading and transfer was verified with Ponceau S staining.
Mentions: Measurements of binding properties of the components of the type I and II receptors and recent structural characterization of type I and II IL-4 receptors (28) suggested that relative receptor chain expression might provide a mechanism to regulate the relative potency of IL-4 and -13. Indeed, the analysis of receptor chain expression in the human monocyte subpopulations supports this idea (Fig. 5 F). We examined the expression of different receptor chains on BMDMs and PMs by flow cytometry, and representative stainings are shown in Fig. 6 A. We quantitated the data from independent stainings in Fig. 6 B. γc expression was detected clearly on both BMDMs and PMs, with fourfold higher expression on PMs. IL-4Rα expression was 2.6-fold higher on PMs than on BMDMs (Fig. 6 B).

Bottom Line: In contrast, IL-13 stimulated greater responses than IL-4 in fibroblasts.The differential expression of IL-4Ralpha, IL-13Ralpha1, and gammac accounted for the distinct IL-4-IL-13 sensitivities of the various cell types.These findings provide an explanation for IL-13's principal function as an "effector" cytokine and IL-4's principal role as an "immunoregulatory" cytokine.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA. junttilai@niaid.nih.gov

ABSTRACT
Interleukin (IL)-4 and -13 are related cytokines sharing functional receptors. IL-4 signals through the type I (IL-4Ralpha/common gamma-chain [gammac]) and the type II (IL-4Ralpha/-13Ralpha1) IL-4 receptors, whereas IL-13 utilizes only the type II receptor. In this study, we show that mouse bone marrow-derived macrophages and human and mouse monocytes showed a much greater sensitivity to IL-4 than to IL-13. Lack of functional gammac made these cells poorly responsive to IL-4, while retaining full responsiveness to IL-13. In mouse peritoneal macrophages, IL-4 potency exceeds that of IL-13, but lack of gammac had only a modest effect on IL-4 signaling. In contrast, IL-13 stimulated greater responses than IL-4 in fibroblasts. Using levels of receptor chain expression and known binding affinities, we modeled the assemblage of functional type I and II receptor complexes. The differential expression of IL-4Ralpha, IL-13Ralpha1, and gammac accounted for the distinct IL-4-IL-13 sensitivities of the various cell types. These findings provide an explanation for IL-13's principal function as an "effector" cytokine and IL-4's principal role as an "immunoregulatory" cytokine.

Show MeSH