Interleukin-15 (IL-15) shares many biological functions with interleukin-2 (IL-2) due to common receptor components. IL-15 binds to the IL-2 receptor (IL-2R) β-chain and the common β-chain receptor in addition to one other IL-15 binding receptor protein (IL-15Rα). Both IL-2R α- and γ-chains are required to promote cell growth in hematopoietic cells. The colonic cryptlike epithelial cell line T84 contains the common γ-chain but lacks the IL-2R β-chain. We report IL-15R α-chain mRNA in T84 cells with the use of reverse transcriptase-polymerase chain reaction. T84 and normal colonic epithelial cells bind a FLAG-IL-15 fusion protein in immunoperoxidase and flow cytometric experiments. In addition, IL-15, but not IL-2, accelerates and enhances the development of transepithelial resistance across T84 monolayers in a dose-dependent fashion. We conclude that normal and T84 colonic epithelial cells express IL-15Rα and are able to bind IL-15. IL-15 can deliver a nonproliferative functional signal in the absence of IL-2R β- chain in T84 cells.
|American Journal of Physiology - Gastrointestinal and Liver Physiology
|Published - May 1997
- Interleukin-15 receptor
- Transepithelial resistance