U937 cells can utilize plasminogen activator to regulate human interferon-gamma.
U937 cells can utilize plasminogen activator to regulate human interferon-gamma.
复制标题
U937细胞可以利用纤溶酶原激活剂来调节人干扰素-γ。
DOI：
10.1089/jir.1993.13.397
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Zhou,WW
中科院分区：
文献类型：
--
作者：
Parmely,MJ;Sterner,KE;Gale,A;Zhou,WW
Urokinase-type plasminogen activator (uPA) converts the proenzyme plasminogen to plasmin and thereby contributes to processes like cell migration, tissue remodeling, and cytokine processing. We report here that uPA produced by the human U937 promonocytic cell line also initiated the inactivation of recombinant interferon-γ (rIFN-γ) by plasmin-mediated proteolysis. When cultured serum-free with plasminogen, U937 promonocytic cells generated measurable levels of plasmin activity and destroyed the antiviral activity of exogenously added rIFN-γ. This effect was not seen in the absence of plasminogen, was prevented by inhibitors of uPA and plasmin, and was accompanied by changes in the electrophoretic mobility of rIFN-γ on polyacrylamide gels, consistent with limited proteolysis of the lymphokine. Culturing U937 cells or blood monocytes for 48 h led to an elevated expression of their surface uPA and an increase in their capacity to produce plasmin and inactivate rIFN-γ. The ability of rIFN-γ to induce Fc receptors on U937 cells could also be prevented by providing the cells with a source of exogenous plasminogen, indicating that U937 cells could control their own activationin vitrothrough the action of uPA. The results of these studies support the conclusion that mononuclear phagocytes have the capacity to use uPA to regulate cytokine activityin vitro.
