title: Chronic endometritis modifies decidualization in human endometrial stromal cells.
abstract: BACKGROUND
  Chronic endometritis (CE) is a continuous inflammation of uterine endometrium, and it is usually symptomless. As CE has been thought not to affect the reproductive status and general health of affected women, its significance has not been explored. However, recent studies have shown that CE is related with repeated implantation failures after in vitro fertilization-embryo transfer, unexplained infertility, and recurrent miscarriages. As decidua differentiates to support the implantation process and maintains the pregnancy, we hypothesized that CE may influence the process of decidualization.
  
  
  METHODS
  Seventeen patients were employed in the experiment involving culture of endometrial stromal cells (ESCs). After obtaining endometrial samples, ESCs were harvested and cultured for 13 days. The concentrations in culture media and the protein expressions in ESCs of prolactin (PRL) and insulin-like growth factor binding protein-1 (IGFBP-1), two well known decidualization markers used in a large number of in vitro models, were analyzed by ELISA and Western blotting, respectively, and the cell numbers were also counted. The mRNA levels of PRL and IGFBP-1 were tested by quantitative real time polymerase chain reaction (RT-PCR). Since sex hormone induce proliferation and differentiation to decidua via binding to the sex hormone receptors (ERα, ERβ, PRA, and PRB), their expression was assessed in another 17 patients' paraffin-embedded endometrial tissue specimens by immunohistochemistry and semi-quantified by H-score.
  
  
  RESULTS
  Increased cell numbers and reduced secretion of PRL and IGFBP-1 were detected by ELISA in the ESCs of CE patients after culture for 13 days compared with non-CE patients. The decreased protein expression of IGFBP-1 in ESCs of CE patients was detected by Western blotting. The decreased expression of PRL mRNA and IGFBP-1 mRNA were detected by RT-PCR. Increased expressions of ERα, ERβ, PRA, and PRB were observed in the stromal cells of CE patients in comparison to non-CE patients, whereas increased expressions of ERα and ERβ were detected in the glandular cells of CE.
  
  
  CONCLUSIONS
  Our data suggests that CE modifies decidualization of human ESC through untuning the function of sex steroid hormone receptor.
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.|Department of Obstetrics and Gynecology, 1st Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, 150001, China.
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan. kimurafu@belle.shiga-med.ac.jp.
authors.forename: Fuminori
authors.identifier: http://orcid.org/0000-0002-9840-4227
authors.initials: F
authors.lastname: Kimura
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Luyi
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Department of Clinical Sciences and Laboratory Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata City, Osaka, 573-1010, Japan.
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Ishida
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Niwa
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Kimiko
authors.initials: K
authors.lastname: Hirata
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Akie
authors.initials: A
authors.lastname: Takebayashi
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Takashima
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Department of Clinical Laboratory Medicine, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Kushima
authors.affiliation: Department of Obstetrics and Gynecology, 1st Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, 150001, China. GuangmeiZhang@126.com.
authors.forename: Guangmei
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Obstetrics and Gynecology, Shiga University of Medical Science, Seta Tsukinowa-cho, Otsu, 520-2192, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Murakami
mesh_terms: D000328:Adult; D015153:Blotting, Western; D002452:Cell Count; D002478:Cells, Cultured; D002908:Chronic Disease; D003656:Decidua / Q000378:metabolism* / Q000473:pathology; D004716:Endometritis / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D004717:Endometrium / Q000378:metabolism* / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000235:genetics / Q000378:metabolism; D011388:Prolactin / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017154:Stromal Cells / Q000378:metabolism*
chemical_list: C032231:IGFBP1 protein, human; D018970:Insulin-Like Growth Factor Binding Protein 1; D011388:Prolactin
keywords: Chronic endometritis; Decidualization; Endometrial stromal cells; IVF; Sex hormone receptor