Identification of the proteolytic enzyme which cleaves human p75 TNF receptor in vitro.
The extracellular domains of the human 55 and 75 kD TNF receptors (p55 and p75 TNF-R) are proteolytically cleaved to produce 30 and 40 kD soluble fragments, respectively. In this study, the enzymatic activity involved in the cleavage of human p75 TNF-R, named TNF-R releasing enzyme (TRRE), was identified in the culture supernatant of PMA-stimulated THP-1 cells using an activity assay system established by our group. When THP-1 cells were stimulated with PMA, TRRE was released rapidly into the supernatant, reaching maximal activity within 3 hours. The release of TRRE into the culture supernatant depended on the concentration of PMA and FCS. TRRE activity was partially inhibited by chelating agents, suggesting that TRRE may be a metallo-protease-like enzyme. This is the first successful attempt to establish a stable TRRE source with a reliable assay system.
Katsura
K
K
Department of Molecular Biology and Biochemistry, University of California, Irvine 92717-3900, USA.
Park
M
M
Gatanaga
M
M
Yu
E C
EC
Takishima
K
K
Granger
G A
GA
Gatanaga
T
T
D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis / Q000378:metabolism*; D002460:Cell Line; D002522:Chlorocebus aethiops; D010450:Endopeptidases / Q000378:metabolism*; D004795:Enzyme Stability; D006358:Hot Temperature; D006801:Humans; D007700:Kinetics; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism; D010446:Peptide Fragments / Q000302:isolation & purification; D011480:Protease Inhibitors / Q000494:pharmacology; D018124:Receptors, Tumor Necrosis Factor / Q000096:biosynthesis / Q000378:metabolism*; D047889:Receptors, Tumor Necrosis Factor, Type II; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014162:Transfection
D015703:Antigens, CD; D010446:Peptide Fragments; D011480:Protease Inhibitors; D018124:Receptors, Tumor Necrosis Factor; D047889:Receptors, Tumor Necrosis Factor, Type II; D011994:Recombinant Proteins; D010450:Endopeptidases; C099844:TNF-R releasing enzyme; D013755:Tetradecanoylphorbol Acetate