Soluble cytokine receptors are present in normal human urine.
Affinity chromatography of crude human urinary proteins on either human rIL-6, human rIFN-gamma, or anti-IFN-gamma-R mAb yielded the two respective soluble receptors in significant quantities. A single sequence of 30 amino acid residues was obtained by NH2-terminal microsequencing of the protein peak purified in tandem by affinity chromatography on an IL-6 column and reversed-phase HPLC. This sequence was identical to the predicted NH2-terminal sequence of IL-6-R as previously reported. Analysis of the eluted proteins from both IFN-gamma and anti-IFN-gamma-R columns by inhibition of solid phase RIA, ELISA, SDS-PAGE, and Western blotting proved the existence of soluble IFN-gamma-R in normal urine. Our finding, together with the already known presence of urinary TNF binding proteins and a soluble IL-2-R both in plasma and in urine, indicates that release of soluble cytokine receptors into body fluids is a general phenomenon that occurs under normal physiological conditions.
Novick
D
D
Department of Virology, Weizmann Institute of Science, Rehovot, Israel.
Engelmann
H
H
Wallach
D
D
Rubinstein
M
M
D000595:Amino Acid Sequence; D015153:Blotting, Western; D002846:Chromatography, Affinity; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism*; D015850:Interleukin-6 / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011971:Receptors, Immunologic / Q000652:urine*; D017471:Receptors, Interferon; D019947:Receptors, Interleukin-6; D011994:Recombinant Proteins; D012995:Solubility
D015850:Interleukin-6; D011971:Receptors, Immunologic; D017471:Receptors, Interferon; D019947:Receptors, Interleukin-6; D011994:Recombinant Proteins; D007371:Interferon-gamma