title: Guinea pig genital tract lipidome reveals in vivo and in vitro regulation of phosphatidylcholine 16:0/18:1 and contribution toChlamydia trachomatisserovar D infectivity.
abstract: BACKGROUND
  Chlamydia trachomatis(Ct), is the leading cause of sexually transmitted infections worldwide. Host transcriptomic- or proteomic profiling studies have identified key molecules involved in establishment of Ct infection or the generation of anti Ct-immunity. However, the contribution of the host metabolome is not known.
  
  
  OBJECTIVE
  The objective of this study was to determine the contribution of host metabolites in genital Ct infection.
  
  
  METHODS
  We used high-performance liquid chromatography-mass spectrometry, and mapped lipid profiles in genital swabs obtained from female guinea pigs at days 3, 9, 15, 30 and 65 post Ct serovar D intravaginal infection.
  
  
  RESULTS
  Across all time points assessed, 13 distinct lipid species including choline, ethanolamine and glycerol were detected. Amongst these metabolites, phosphatidylcholine (PC) was the predominant phospholipid detected from animals actively shedding bacteria i.e., at 3, 9, and 15 days post infection. However, at days 30 and 65 when the animals had cleared the infection, PC was observed to be decreased compared to previous time points. Mass spectrometry analyses of PC produced in guinea pigs (in vivo) and 104C1 guinea pig cell line (in vitro) revealed distinct PC species following Ct D infection. Amongst these, PC 16:0/18:1 was significantly upregulated following Ct D infection (p< 0.05, >twofold change) in vivo and in vitro infection models investigated in this report. Exogenous addition of PC 16:0/18:1 resulted in significant increase in Ct D in Hela 229 cells.
  
  
  CONCLUSIONS
  This study demonstrates a role for host metabolite, PC 16:0/18:1 in regulating genital Ct infection in vivo and in vitro.
authors.affiliation: South Texas Center for Emerging Infectious Diseases and Center for Excellence in Infection Genomics, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: Shradha
authors.initials: S
authors.lastname: Wali
authors.affiliation: South Texas Center for Emerging Infectious Diseases and Center for Excellence in Infection Genomics, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: Rishein
authors.initials: R
authors.lastname: Gupta
authors.affiliation: South Texas Center for Emerging Infectious Diseases and Center for Excellence in Infection Genomics, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: Jieh-Juen
authors.initials: JJ
authors.lastname: Yu
authors.affiliation: Department of Chemistry, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: Adelphe
authors.initials: A
authors.lastname: Mfuh
authors.affiliation: Department of Biochemistry, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Gao
authors.affiliation: South Texas Center for Emerging Infectious Diseases and Center for Excellence in Infection Genomics, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: M Neal
authors.initials: MN
authors.lastname: Guentzel
authors.affiliation: South Texas Center for Emerging Infectious Diseases and Center for Excellence in Infection Genomics, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Chambers
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Lembah Pantai Kuala Lumpur, 50603 Kuala Lumpur, Malaysia.
authors.forename: Sazaly
authors.initials: S
authors.lastname: Abu Bakar
authors.affiliation: Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, 7702 Floyd Curl Drive, San Antonio, TX 78229, USA.
authors.forename: Guangming
authors.initials: G
authors.lastname: Zhong
authors.affiliation: South Texas Center for Emerging Infectious Diseases and Center for Excellence in Infection Genomics, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA.
authors.forename: Bernard P
authors.initials: BP
authors.lastname: Arulanandam
keywords: Chlamydia trachomatis serovar D; Guinea pig; Intravaginal infection; Lipids; Phosphatidylcholine