title: Characterization of Toll-like receptors in the female reproductive tract in humans.
abstract: BACKGROUND
  Rapid innate immune defences against infection involve the recognition of invading pathogens by specific pattern recognition receptors recently attributed to the family of Toll-like receptors (TLR). Little is known about the in vivo protein expression or distribution of TLR in the female reproductive tract in humans. It is likely that TLR distribution in the female reproductive tract reflects the immunological tolerance to the commensal organisms in lower parts of the tract (vagina, ectocervix and, partially, endocervix) and the intolerance to commensal microbial flora in the upper tract (the uterus and uterine tubes).
  
  
  METHODS
  Using immunohistochemistry techniques, distribution of TLR1-6 was studied in surgical sections from the vagina, ecto- and endocervix, endometrium and uterine tubes, obtained from patients undergoing abdominal hysterectomy for benign gynaecological conditions.
  
  
  RESULTS
  TLR1, 2, 3, 5 and 6 were present in the epithelia of different regions of female reproductive tract. However, TLR4 was only present in the endocervix, endometrium and uterine tubes and absent in vagina and ectocervix. In addition, a secretory form of TLR4 seems to be produced by the endocervical glands.
  
  
  CONCLUSIONS
  TLR4 may play an important role in modulation of immunological tolerance in the lower parts of the female reproductive tract, and in host defence against ascending infection.
authors.affiliation: Academic Unit of Reproductive and Developmental Medicine, University of Sheffield, UK. A.Fazeli@Sheffield.AC.uk
authors.forename: A
authors.initials: A
authors.lastname: Fazeli
authors.forename: C
authors.initials: C
authors.lastname: Bruce
authors.forename: D O
authors.initials: DO
authors.lastname: Anumba
mesh_terms: D000328:Adult; D005260:Female; D005836:Genitalia, Female / Q000502:physiology*; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008875:Middle Aged; D011956:Receptors, Cell Surface / Q000378:metabolism*; D051194:Toll-Like Receptor 1; D051197:Toll-Like Receptor 4; D051216:Toll-Like Receptor 6; D051193:Toll-Like Receptors
chemical_list: D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; C495345:TLR4 protein, human; C495368:TLR6 protein, human; D051194:Toll-Like Receptor 1; D051197:Toll-Like Receptor 4; D051216:Toll-Like Receptor 6; D051193:Toll-Like Receptors