Possible identity of IL-8 converting enzyme in human fibroblasts as a cysteine protease.
A converting activity was characterized in human diploid fibroblasts, which secrete 72IL-8 and 77IL-8 in treatment with IFN-beta and poly I: poly C. 77IL-8 was significantly converted to 72IL-8 by a partially purified fraction of the culture supernatant of human diploid fibroblasts. The converting activity, which was temperature-dependent and optimal at pH 6, was completely inhibited by cysteine protease inhibitors, antipain dihydrochloride and E-64, but not by other types of protease inhibitors. These data clearly show that human diploid fibroblasts are capable of processing IL-8 to produce a mature IL-8 and that the putative converting enzyme appears to be a cysteine protease.
Ohashi
Kensaku
K
Pharmaceutical Research Laboratories, Toray Industries, Inc, 1111 Tebiro, Kanagawa Kamakura 248-8555, Japan. Kenasaku_Ohashi@tmc.toray.co.jp
Sano
Emiko
E
Nakaki
Toshio
T
Naruto
Masanobu
M
D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000096:biosynthesis*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D005347:Fibroblasts / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D006801:Humans; D016899:Interferon-beta / Q000494:pharmacology; D016209:Interleukin-8 / Q000096:biosynthesis*; D011070:Poly I-C / Q000494:pharmacology; D011499:Protein Processing, Post-Translational
D015853:Cysteine Proteinase Inhibitors; D016209:Interleukin-8; D016899:Interferon-beta; D003546:Cysteine Endopeptidases; D011070:Poly I-C