title: Intramuscular 17α-hydroxyprogesterone caproate administration attenuates immunoresponsiveness of maternal peripheral blood mononuclear cells.
abstract: OBJECTIVE
  17α-hydroxyprogesterone caproate (17P) may decrease risk of prematurity by suppressing maternal immunity. We hypothesized that in vivo 17P treatment attenuates immunoresponsiveness of peripheral blood mononuclear cells (PBMCs).
  
  
  METHODS
  Study subjects were gravidas receiving weekly prophylactic intramuscular 17P injections. Peripheral blood samples were obtained at 21-27 weeks' gestation. Gestational age-matched, drug-naïve gravidas served as controls. To simulate infection, isolated PBMCs were stimulated with lipoteichoic acid (LTA) or lipopolysaccharide (LPS). Extracellular interleukin-6 (IL-6) concentrations were quantified by an enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Unstimulated IL-6 levels were comparable in PBMCs derived from drug-naïve and 17P-treated subjects. LPS and LTA induced a dose-dependent elevation of IL-6 in control PBMCs. In patients who received exogenous 17P, LPS, and LTA stimulated induction of IL-6 was significantly decreased compared with controls (P = .005 and P = .02).
  
  
  CONCLUSIONS
  In vivo 17P attenuated immunoreactivity of PBMCs in our in vitro model of Gram-positive and Gram-negative bacterial infection.
authors.affiliation: Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Madigan Army Medical Center, Joint Base Lewis McChord, Tacoma, WA, USA. lisa.foglia@us.army.mil
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Foglia
authors.forename: Danielle L
authors.initials: DL
authors.lastname: Ippolito
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Stallings
authors.forename: Craig M
authors.initials: CM
authors.lastname: Zelig
authors.forename: Peter G
authors.initials: PG
authors.lastname: Napolitano
mesh_terms: D000077713:17 alpha-Hydroxyprogesterone Caproate; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005865:Gestational Age; D006801:Humans; D006908:Hydroxyprogesterones / Q000008:administration & dosage*; D056747:Immunomodulation; D007165:Immunosuppression Therapy / Q000379:methods; D066298:In Vitro Techniques; D007273:Injections, Intramuscular; D015850:Interleukin-6 / Q000276:immunology* / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology*; D011247:Pregnancy / Q000097:blood / Q000276:immunology*; D047928:Premature Birth / Q000276:immunology* / Q000517:prevention & control; D012016:Reference Values
chemical_list: D006908:Hydroxyprogesterones; D015850:Interleukin-6; D000077713:17 alpha-Hydroxyprogesterone Caproate