title: Qualitative and quantitative analysis of T lymphocytes during normal human pregnancy.
abstract: OBJECTIVE
  Human reproduction involves contact between cells which are allogeneic to one another, however the fetus not only survives but thrives.
  
  
  METHODS
  Aspects of T-cell-mediated immunity during normal human pregnancy were studied. PBMNCs of pregnant and nonpregnant women were stimulated with PHA and cytomegalovirus antigens (CMV). The capacity of stimulated cells to proliferate, to produce IL-2 and IFN-gamma, to express IL-2 receptor (IL2R1) and the effect of rIL2 on the proliferation rate of lymphocytes were examined. FACS was utilized for T-cell subset comparisons.
  
  
  RESULTS
  The proliferation rate, IL-2, and IFN-gamma synthesis were all significantly impaired at suboptimal concentration of PHA throughout pregnancy. Exogenous rIL-2 corrected this depression of cell-mediated immunity (CMI). At optimal concentration of PHA, proliferation rate and production of IFN-gamma and IL-2 were all decreased. Exogenous rIL-2 corrected these deficits only in the third trimester. Third trimester pregnant women demonstrated a significant depression of proliferation as well as IL-2 and IFN-gamma production after CMV stimulation, which was partially corrected by exogenous rIL-2. FACS analysis suggested that after stimulation by CMV and optimal concentration of PHA, T cells were activated and both CD4+ and CD8+ lymphoblasts expressed normal density of IL-2R1. With suboptimal PHA, the number of activated CD4+ and CD4+IL2R1+ cells were diminished and CD4+ and CD8+ T lymphoblasts expressed lower number of IL2R1.
  
  
  CONCLUSIONS
  CD4 T helper (Th1) cell function is down regulated progressively during the three trimesters of pregnancy without changes in the quantity of T cell subsets.
authors.affiliation: Department of Pediatrics, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, New Brunswick 08903-0019, USA.
authors.forename: F
authors.initials: F
authors.lastname: Sabahi
authors.forename: M
authors.initials: M
authors.lastname: Rola-Plesczcynski
authors.forename: S
authors.initials: S
authors.lastname: O'Connell
authors.forename: L D
authors.initials: LD
authors.lastname: Frenkel
mesh_terms: D000328:Adult; D000956:Antigens, Viral / Q000276:immunology / Q000494:pharmacology; D003587:Cytomegalovirus / Q000276:immunology; D000939:Epitopes / Q000032:analysis; D005260:Female; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D018655:Lymphocyte Count; D008222:Lymphokines / Q000096:biosynthesis; D011247:Pregnancy; D015375:Receptors, Interleukin-2 / Q000032:analysis; D011994:Recombinant Proteins / Q000494:pharmacology; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism
chemical_list: D000956:Antigens, Viral; D000939:Epitopes; D007376:Interleukin-2; D008222:Lymphokines; D015375:Receptors, Interleukin-2; D011994:Recombinant Proteins