Identification and characterization of the rat intestinal epithelial cell (IEC-18) interleukin-1 receptor.
Interleukin-1 (IL-1), an important mediator of inflammation, may act in chronic inflammatory disorders of the intestine such as idiopathic inflammatory bowel diseases. Although the IL-1 receptor (IL-1R) has been studied extensively in many cell lines, including T cells, B cells, and fibroblasts, it has not been demonstrated on intestinal epithelial cells. IL-1 affects intestinal epithelial cell proliferation in vitro, suggesting the presence of IL-1Rs on intestinal epithelium. This paper demonstrates and further characterizes an IL-1R in a rat intestinal epithelial cell. Cells from rat intestinal epithelial cell line IEC-18 were grown to confluence in six-well plates, and association studies with 125I-labeled IL-1 beta to determine specific binding and equilibrium conditions were performed. A competitive-inhibition curve verified the IL-1 concentration required to saturate the IL-1R, and a Scatchard plot revealed a dissociation constant (Kd) of 1.2 x 10(-10) M, with 1,000 receptors per epithelial cell. Binding studies using increasing concentrations of 125I IL-1 beta alone confirmed the receptor density. Cross-linking 125I-IL-1 beta to the IEC-18 IL-1R demonstrated an IL-1R of approximately 80.5 kDa. cDNA transcribed from IEC-18 mRNA was used as a template for amplification of a segment of the IL-1R using complementary oligonucleotides. The resulting sequence of the IL-1R demonstrated a high degree of homology with both the human and mouse type I IL-1R.(ABSTRACT TRUNCATED AT 250 WORDS)
Sutherland
D B
DB
Department of Internal Medicine, University of Iowa College of Medicine, Iowa City 52242.
Varilek
G W
GW
Neil
G A
GA
D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D002460:Cell Line; D017124:Conserved Sequence; D017931:DNA Primers; D018076:DNA, Complementary / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004848:Epithelium / Q000276:immunology / Q000378:metabolism; D005347:Fibroblasts / Q000276:immunology / Q000378:metabolism; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism*; D007422:Intestines; D007700:Kinetics; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016133:Polymerase Chain Reaction / Q000379:methods; D051381:Rats; D018123:Receptors, Interleukin / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D023062:Receptors, Interleukin-8A; D012689:Sequence Homology, Nucleic Acid; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D014158:Transcription, Genetic
D017931:DNA Primers; D018076:DNA, Complementary; D016209:Interleukin-8; D018123:Receptors, Interleukin; D023062:Receptors, Interleukin-8A