IL‐10 enhances IL‐2‐induced proliferation and cytotoxicity by human intestinal lymphocytes

• Published in: Clinical and experimental immunology Vol. 119; no. 3; pp. 426 - 432
• Main Author: Ebert, E. C.
• Format: Journal Article
• Language: English
• Published: Oxford BSL Blackwell Science Ltd 01.03.2000; Blackwell; Oxford University Press; Blackwell Science Inc
• Subjects: Biological and medical sciences; Cell Differentiation - immunology; Cell Division - immunology; Fundamental and applied biological sciences. Psychology; Humans; IL‐10; IL‐2; Immunity, Mucosal; Inflammation; inflammatory bowel disease; Inflammatory Bowel Diseases - immunology; interferon‐gamma; Interleukin-10 - immunology; Interleukin-10 - pharmacology; Interleukin-2 - immunology; Intestines - immunology; Intestines - pathology; Lymphocyte Activation; lymphokine‐activated killer activity; Molecular and cellular biology; Original; T-Lymphocytes, Cytotoxic - immunology; T-Lymphocytes, Cytotoxic - pathology; tumour necrosis factor; Human; Local immunity; Interleukin 2; Cytokine; Interleukin 10; Gut; T-Lymphocyte; Cytotoxicity; Immune regulation; Inflammation; Tumor necrosis factor α; Gamma interferon
• ISSN: 0009-9104; 1365-2249
• DOI: 10.1046/j.1365-2249.2000.01147.x

IL‐10 modulation of human intestinal T lymphocyte functions was studied for the first time. Lymphocyte proliferation was determined by 3H‐thymidine incorporation; cytokine production, by ELISA; expression of surface markers, by immunofluorescence and flow cytometric analysis; and cytotoxicity, by lysis of 51Cr‐labelled target cells. IL‐10 blocked phytohaemagglutinin (PHA)‐induced activation and proliferation of CD8+ T cells from the epithelium and lamina propria. It was a greater inhibitor of IL‐2, interferon‐gamma, and tumour necrosis factor‐alpha production than were IL‐4 or transforming growth factor‐beta. In contrast, IL‐10 enhanced IL‐2‐stimulated proliferation of both CD4+ and CD8+ T cells by increasing cell division after activation. It also augmented IL‐2‐ but not IL‐15‐induced cytotoxicity of intestinal lymphocytes against colon cancer by a mechanism independent of natural killer cells. In conclusion, IL‐10 blocking of proinflammatory cytokine secretion probably reduces intestinal inflammation. IL‐10 augmentation of IL‐2‐induced cytotoxicity may help to maintain host defence.