Protease nexin-1 activity in cultured Schwann cells.
We report that protease nexin-1 (PN-1), a serine protease inhibitor known to have neurite-promoting effects, is made by Schwann cells in tissue culture. Three modalities have been used to demonstrate the presence of PN-1 in Schwann cell cultures. Immunostaining of the cultures with anti-PN-1 antibody gives positive staining over cells and matrix. Western blots of Schwann cell conditioned medium (CM) using anti-PN-1 antibody show a band that co-migrates with the PN-1 standard at 45 kDa. Biochemical assay for protease inhibitory activity shows that CM inhibits thrombin activity in a calorimetric assay. The CM-mediated inhibition of thrombin is reversed if the CM is pre-incubated with anti-PN-1 antibody.
Mulligan
L P
LP
Center for Neurologic Disease, Brigham and Women's Hospital, Boston, MA 02215.
Rosenblatt
D E
DE
Toms
R
R
Johnson
D
D
D016564:Amyloid beta-Protein Precursor; D000818:Animals; D015153:Blotting, Western; D002352:Carrier Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D003470:Culture Media; D007150:Immunohistochemistry / Q000379:methods; D011480:Protease Inhibitors / Q000378:metabolism; D058255:Protease Nexins; D011956:Receptors, Cell Surface; D012583:Schwann Cells / Q000378:metabolism*; D013194:Staining and Labeling
D016564:Amyloid beta-Protein Precursor; D002352:Carrier Proteins; D003470:Culture Media; D011480:Protease Inhibitors; D058255:Protease Nexins; D011956:Receptors, Cell Surface