title: Increased levels of interleukin-15 in the peritoneal fluid of women with endometriosis: inverse correlation with stage and depth of invasion.
abstract: BACKGROUND
  Interleukin (IL)-15 is a novel cytokine with immunoregulatory and angiogenic properties. We compared IL-15 levels in the peritoneal fluid (PF) of women with and without endometriosis.
  
  
  METHODS
  PF samples were obtained from 55 women with endometriosis (23 with superficial peritoneal implants, 19 with deep endometriotic implants and 13 with ovarian endometriomas). Eighteen women with normal pelvic anatomy undergoing tubal sterilization served as controls.
  
  
  RESULTS
  PF IL-15 concentrations were increased in women with endometriosis (2.7 +/- 0.5 pg/ml) versus controls (2.1 +/- 0.3 pg/ml; P < 0.001). However, IL-15 levels were higher in women with superficial peritoneal implants (2.9 +/- 0.5 pg/ml) than women with deep endometriotic implants (2.6 +/- 0.4 pg/ml; P = 0.01) or ovarian endometriomas (2.2 +/- 0.4 pg/ml; P < 0.001). IL-15 was also higher in women with deep implants than in those with endometriomas (P < 0.05). PF IL-15 correlated inversely with both depth of invasion (r = -0.52) and the stage of endometriosis (r = -0.42). PF IL-15 levels demonstrated little variation during the menstrual cycle, and did not discriminate between women with infertility or pelvic pain.
  
  
  CONCLUSIONS
  PF IL-15 levels are increased in women with endometriosis. However, IL-15 levels are inversely correlated with the depth of invasion and disease stage, suggesting a possible role for this cytokine in the early pathogenesis of endometriosis.
authors.affiliation: Department of Obstetrics and Gynecology, Yale University School of Medicine, 333 Cedar Street, New Haven, Connecticut 06520-8063, USA. aydin.arici@yale.edu
authors.forename: Aydin
authors.initials: A
authors.lastname: Arici
authors.forename: Ioannis
authors.initials: I
authors.lastname: Matalliotakis
authors.forename: Anastasia
authors.initials: A
authors.lastname: Goumenou
authors.forename: Georgios
authors.initials: G
authors.lastname: Koumantakis
authors.forename: Simon
authors.initials: S
authors.lastname: Vassiliadis
authors.forename: Belgin
authors.initials: B
authors.lastname: Selam
authors.forename: Neal G
authors.initials: NG
authors.lastname: Mahutte
mesh_terms: D000328:Adult; D001202:Ascitic Fluid / Q000378:metabolism*; D016022:Case-Control Studies; D004715:Endometriosis / Q000150:complications / Q000378:metabolism* / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000209:etiology; D019409:Interleukin-15 / Q000378:metabolism*; D008597:Menstrual Cycle; D009994:Osmolar Concentration; D017699:Pelvic Pain / Q000209:etiology; D010537:Peritoneum / Q000473:pathology
chemical_list: D019409:Interleukin-15