In preeclampsia and hemolysis, elevated liver enzymes and low platelet (HELLP) 
syndrome, impaired trophoblast invasion and excessive fibrin deposition in the 
placental intervillous space is associated with fetal compromise. However, 
little information is available whether modulation of placental protease 
expression--potentially causing impaired trophoblast invasion--is associated 
with the HELLP syndrome. Total RNA and protein were extracted from placental 
tissue from 11 females with HELLP syndrome and 8 controls matched for 
gestational age. mRNA expression of matrix metalloprotease (MMP) -2 and -9, 
tissue inhibitors of metalloprotease (TIMP) -1, -2, and -3, and urokinase-type 
plasminogen activator receptor (uPAR) was determined by Northern blotting. 
Protein expression of MMP-2 and -9, and TIMP-1 and -2 was detected by Western 
blotting and that of uPA, uPAR, and plasminogen activator inhibitor (PAI) -1 by 
ELISA. In patients with HELLP syndrome, mRNA expression of MMP-2 and TIMP-2 was 
decreased, whereas TIMP-1 and -3 levels were unchanged. MMP-9 and uPAR mRNA was 
undetectable in both groups. Protein expression of all investigated proteolytic 
factors remained unchanged. Our findings at the mRNA level suggest a decrease in 
matrix remodeling in placentae from patients with HELLP syndrome compared with 
control pregnancies, although this is not supported at the protein level.