TY - JOUR
T1 - Complexes of tissue-type plasminogen activator and its serpin inhibitor plasminogen-activator inhibitor type 1 are internalized by means of the low density lipoprotein receptor-related protein/α2-macroglobulin receptor
AU - Orth, Kim
AU - Madison, Edwin L.
AU - Gething, Mary Jane
AU - Sambrook, Joseph F.
AU - Herz, Joachim
PY - 1992
Y1 - 1992
N2 - Tissue-type plasminogen activator and urokinase are serine proteases secreted by many cell types that participate in biological processes, such as tissue restructuring, cell migration, and tumor metastasis. Clinically, these proteases are used to dissolve coronary fibrin clots that are the proximal causes of acute myocardial infarction. In vivo, the activity of these enzymes is controlled by plasminogen-activator inhibitors, members of the serpin family of protease inhibitors. This study shows that tissue-type plasminogen activator-inhibitor complexes bind in solution to low density lipoprotein receptor-related protein (LRP), a large heterodimeric ubiquitous membrane receptor. In cultured cells, endocytosis and degradation of these complexes is reduced by polyclonal antibodies directed against LRP and inhibited by a Mr 39,000 protein that binds to LRP and inhibits its interaction with previously known ligands, including apolipoprotein E and α2-macroglobulin. We propose a role for LRP in the clearance of plasminogen activator-inhibitor complexes that is analogous to its function in the endocytosis of α2-macroglobulin-protease complexes.
AB - Tissue-type plasminogen activator and urokinase are serine proteases secreted by many cell types that participate in biological processes, such as tissue restructuring, cell migration, and tumor metastasis. Clinically, these proteases are used to dissolve coronary fibrin clots that are the proximal causes of acute myocardial infarction. In vivo, the activity of these enzymes is controlled by plasminogen-activator inhibitors, members of the serpin family of protease inhibitors. This study shows that tissue-type plasminogen activator-inhibitor complexes bind in solution to low density lipoprotein receptor-related protein (LRP), a large heterodimeric ubiquitous membrane receptor. In cultured cells, endocytosis and degradation of these complexes is reduced by polyclonal antibodies directed against LRP and inhibited by a Mr 39,000 protein that binds to LRP and inhibits its interaction with previously known ligands, including apolipoprotein E and α2-macroglobulin. We propose a role for LRP in the clearance of plasminogen activator-inhibitor complexes that is analogous to its function in the endocytosis of α2-macroglobulin-protease complexes.
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U2 - 10.1073/pnas.89.16.7422
DO - 10.1073/pnas.89.16.7422
M3 - Article
C2 - 1502153
AN - SCOPUS:0026668601
SN - 0027-8424
VL - 89
SP - 7422
EP - 7426
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 16
ER -