title: Elevated concentration of secretory leukocyte protease inhibitor in the cervical mucus before delivery.
abstract: Cervical remodeling during parturition progresses under exquisite regulation by immunologic mediators and proteases. Secretory leukocyte protease inhibitor is a secretory protein that can function as an antimicrobial peptide, an antiinflammatory molecule, and a protease inhibitor. The involvement of secretory leukocyte protease inhibitor in cervical remodeling before and during parturition is understood poorly.
  
  
  
  We aimed to reveal the role of secretory leukocyte protease inhibitor in the cervical remodeling process before normal term delivery and to evaluate its utility as a predictive biomarker for timing of delivery.
  
  
  
  Cervical mucus samples were collected prospectively at weekly prenatal visits from a cohort of pregnant women at term. The secretory leukocyte protease inhibitor concentrations in 95 mucus samples that were obtained from 49 women with uncomplicated pregnancy who subsequently underwent normal vaginal delivery were assessed. Alterations in secretory leukocyte protease inhibitor concentrations at term and the association of secretory leukocyte protease inhibitor levels with the time to delivery were analyzed.
  
  
  
  A moderate positive correlation with significance was detected between cervical mucus secretory leukocyte protease inhibitor concentrations and days to delivery (r = 0.38; P = .0001). The secretory leukocyte protease inhibitor concentration was significantly higher in samples that were collected within 7 days of delivery when compared with samples that were collected >7 days before delivery (P = .001). Secretory leukocyte protease inhibitor concentrations were also significantly higher in samples from women with premature rupture of membranes when compared with those without premature rupture of membranes (P = .01), all of whom delivered within 7 days. A logistic regression analysis revealed that the cervical secretory leukocyte protease inhibitor level was a significant parameter for the prediction of the onset of delivery. (P = .017; unit odds ratio, 1.28; 95% confidence interval, 1.07-1.61). A cut-off value of cervical secretory leukocyte protease inhibitor/total protein to predict delivery within 7 days was determined to be 1.62 μg/mg (sensitivity, 0.69; specificity, 0.72) using receiver operating characteristic curve-analysis.
  
  
  
  Secretory leukocyte protease inhibitor concentrations in the cervical mucus elevate progressively before delivery in uncomplicated term pregnancies. Our findings suggest that cervical secretory leukocyte protease inhibitor is a candidate biomarker for delivery prediction.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Taiki
authors.initials: T
authors.lastname: Samejima
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan. Electronic address: tnag-tky@umin.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nagamatsu
authors.affiliation: Department of Obstetrics, Gynecology and Women's Health, University of Missouri, Columbia, MO.
authors.forename: Danny J
authors.initials: DJ
authors.lastname: Schust
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Nao
authors.initials: N
authors.lastname: Itaoka
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Iriyama
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Komatsu
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Kawana
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Osuga
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Fujii
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D002582:Cervix Mucus / Q000378:metabolism*; D036861:Delivery, Obstetric; D005260:Female; D005322:Premature Rupture of Fetal Membranes / Q000378:metabolism; D006801:Humans; D016015:Logistic Models; D011247:Pregnancy; D011446:Prospective Studies; D053481:Secretory Leukocyte Peptidase Inhibitor / Q000378:metabolism*; D047929:Term Birth
chemical_list: D015415:Biomarkers; D053481:Secretory Leukocyte Peptidase Inhibitor
keywords: antiprotease; biomarker; delivery; inflammation; prediction; secretory leukocyte protease inhibitor; term pregnancy