Children's National Health System Posters
Characterization of IL-4 Effects on Urothelial Cell Cycling
Document Type
Poster
Abstract Category
Basic Biomedical Sciences
Keywords
IL-4, urothelial cell, cytokine, urology, basic science
Publication Date
Spring 2019
Abstract
Background: IL-4 is a potent cytokine which is involved in a myriad of immune functions, including tissue repair. Previous studies have shown that urothelial cells express IL-4 receptors and that IL-4 receptor signaling is important in type 2 inflammation in the bladder. A single study has suggested that IL-4 reduces apoptosis in urothelial cancer cells. However, little is otherwise known regarding whether IL-4 directly mediates urothelial effects. We hypothesize that IL-4 will polarize the immune system toward a tissue reparative phenotype by inducing cell cycle and urothelial cell proliferation. Methods: Urothelial cells were cultured with IL-4 at various concentrations (10 ng/mL, 100 ng/mL, and 1000 ng/mL) and subjected to cell cycle and CFSE analysis after 48 hours of incubation. For cell cycle analysis, the cells were treated with propidium iodide, and their DNA quantified by flow cytometry to distinguish cells in different phases of the cell cycle. To measure cell proliferation, cells were stained with CSFE dye and then analyzed by flow cytometry to evaluate for cell proliferation as quantified by dye intensity. Results: Cell cycle analysis revealed that at increasing concentrations of IL-4, there was a statistically significant increase of cells within the G2+M phases of cell division. CFSE analysis also similarly showed a statistically significant increase in proliferation of cells at an IL-4 concentration of 100 ng/mL. Conclusion: IL-4 affects urothelial cells by driving both cell cycle alterations and urothelial cell proliferation. There was an IL-4 concentration-dependent increase in urothelial cell proliferation up to 100 ng/mL, but not at higher concentrations. This may indicate that there is an optimum concentration at which IL-4 mediates its effects of urothelial function. Further studies are needed to characterize the downstream transcriptional function of IL-4 on urothelial cells. Our results suggest that IL-4 directly mediates urothelial effects, including induction of cell proliferation and driving cell cycle. This points to a direct role for this central cytokine in modulation of urothelial biology.
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Open Access
1
Characterization of IL-4 Effects on Urothelial Cell Cycling
Background: IL-4 is a potent cytokine which is involved in a myriad of immune functions, including tissue repair. Previous studies have shown that urothelial cells express IL-4 receptors and that IL-4 receptor signaling is important in type 2 inflammation in the bladder. A single study has suggested that IL-4 reduces apoptosis in urothelial cancer cells. However, little is otherwise known regarding whether IL-4 directly mediates urothelial effects. We hypothesize that IL-4 will polarize the immune system toward a tissue reparative phenotype by inducing cell cycle and urothelial cell proliferation. Methods: Urothelial cells were cultured with IL-4 at various concentrations (10 ng/mL, 100 ng/mL, and 1000 ng/mL) and subjected to cell cycle and CFSE analysis after 48 hours of incubation. For cell cycle analysis, the cells were treated with propidium iodide, and their DNA quantified by flow cytometry to distinguish cells in different phases of the cell cycle. To measure cell proliferation, cells were stained with CSFE dye and then analyzed by flow cytometry to evaluate for cell proliferation as quantified by dye intensity. Results: Cell cycle analysis revealed that at increasing concentrations of IL-4, there was a statistically significant increase of cells within the G2+M phases of cell division. CFSE analysis also similarly showed a statistically significant increase in proliferation of cells at an IL-4 concentration of 100 ng/mL. Conclusion: IL-4 affects urothelial cells by driving both cell cycle alterations and urothelial cell proliferation. There was an IL-4 concentration-dependent increase in urothelial cell proliferation up to 100 ng/mL, but not at higher concentrations. This may indicate that there is an optimum concentration at which IL-4 mediates its effects of urothelial function. Further studies are needed to characterize the downstream transcriptional function of IL-4 on urothelial cells. Our results suggest that IL-4 directly mediates urothelial effects, including induction of cell proliferation and driving cell cycle. This points to a direct role for this central cytokine in modulation of urothelial biology.
Comments
Presented at Research Days 2019.