title: Cystatin A protease inhibitor and cysteine proteases in human cervicovaginal fluid in term pregnancy and labor.
abstract: OBJECTIVE
  The purpose of this study was to investigate the temporal changes in immunoreactive cystatin A and the enzymatic activity of cathepsins B, H, L, and S in human cervicovaginal fluid (CVF) in late pregnancy and spontaneous labor.
  
  
  METHODS
  CVF was collected weekly (n = 95 women) from 36 weeks gestation until spontaneous term labor. Cystatin A was quantified using enzyme-linked immunosorbent assay. The enzyme activity of cathepsins B, H, L, and S was measured with fluorometric enzyme assay kits.
  
  
  RESULTS
  Cystatin A significantly decreased towards (P = .016, 2-way analysis of variance) and during labor (P < .001, 2-way analysis of variance). Enzymatic activity of cathepsins B, H, and S did not change with labor onset (P = .452, P = .703, P = .411, respectively, 2-way analysis of variance).
  
  
  CONCLUSIONS
  In late gestation, CVF-decreased expression of the cysteine protease inhibitor, cystatin A, is associated with labor. Although the role and contribution of cystatin A to increased extracellular matrix remodeling has yet to be elucidated, the data that were obtained are consistent with this hypothesis.
authors.affiliation: Department of Obstetrics & Gynecology, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Yujing J
authors.initials: YJ
authors.lastname: Heng
authors.forename: Megan K W
authors.initials: MK
authors.lastname: Di Quinzio
authors.forename: Michael
authors.initials: M
authors.lastname: Permezel
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Rice
authors.forename: Harry M
authors.initials: HM
authors.lastname: Georgiou
mesh_terms: D000328:Adult; D001826:Body Fluids / Q000201:enzymology*; D002403:Cathepsins / Q000032:analysis*; D055312:Cystatin A / Q000032:analysis*; D057056:Cysteine Proteases / Q000032:analysis*; D005260:Female; D006801:Humans; D007743:Labor, Obstetric; D011247:Pregnancy; D011480:Protease Inhibitors / Q000032:analysis; D047929:Term Birth
chemical_list: D055312:Cystatin A; D011480:Protease Inhibitors; D002403:Cathepsins; D057056:Cysteine Proteases