title: Changes in T, B, and NK lymphocyte subsets during and after normal pregnancy.
abstract: OBJECTIVE
  Pregnancy affects the maternal immune system and the clinical course of maternal diseases. Here we report the changes in the detailed lymphocyte subsets of helper T cells, suppressor T cells, CD5+ B cells, T cell receptor (TCR) alpha beta-positive T cells (T alpha beta cells), TCR alpha beta-negative T cell (T gamma delta cells), and other during and after pregnancy through to one year postpartum, and discuss the significance of the changes.
  
  
  METHODS
  The absolute numbers of helper T cells, suppressor T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), CD5- B cells, CD5+ B cells, and NK cell subsets were examined by two-color flow cytometry in peripheral blood from 51 healthy non-pregnant women, 106 healthy pregnant women, and 148 healthy postpartum women.
  
  
  RESULTS
  In early pregnancy, the numbers of suppressor T cells and NK cells with strong cytotoxicity (NK+3 cells) increased, and the number of cytotoxic T cells decreased. In late pregnancy, the helper T cell and NK+3 cell numbers decreased. T alpha beta, CD5- B and CD5+ B cells decreased during pregnancy. After delivery, helper T cells and cytotoxic T cells increased from 1 to 4 months postpartum, and suppressor T cells increased at 7 months postpartum. TCR alpha beta-negative T cells increased at 4 to 10 months postpartum. Both CD5- and CD5+ B cells decreased further at 1 month postpartum, but CD5+ B cells increased markedly at 7 to 10 months postpartum.
  
  
  CONCLUSIONS
  These data indicate that 1) early increases of suppressor T cells and NK+3 cells during pregnancy may be related to the mechanism to accept or reject the fetus in early pregnancy, respectively; 2) late decreases of helper T cells and NK+3 cells may be related to the maintenance of pregnancy: 3) postpartum increases of helper T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), and CD5+ B cells may be related to the postpartum aggravation of autoimmune diseases; and 4) the immunological effects of pregnancy remains until about 1 year after delivery.
authors.affiliation: Department of Laboratory Medicine, Osaka University Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Watanabe
authors.forename: Y
authors.initials: Y
authors.lastname: Iwatani
authors.forename: T
authors.initials: T
authors.lastname: Kaneda
authors.forename: Y
authors.initials: Y
authors.lastname: Hidaka
authors.forename: N
authors.initials: N
authors.lastname: Mitsuda
authors.forename: Y
authors.initials: Y
authors.lastname: Morimoto
authors.forename: N
authors.initials: N
authors.lastname: Amino
mesh_terms: D000328:Adult; D016175:B-Lymphocyte Subsets / Q000276:immunology; D018956:CD5 Antigens / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology; D018655:Lymphocyte Count; D016131:Lymphocyte Subsets / Q000276:immunology*; D049590:Postpartum Period / Q000097:blood / Q000276:immunology; D011247:Pregnancy / Q000097:blood / Q000276:immunology*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D018956:CD5 Antigens; D016693:Receptors, Antigen, T-Cell, alpha-beta