title: Treg cells are negatively correlated with increased memory B cells in pre-eclampsia while maintaining suppressive function on autologous B-cell proliferation.
abstract: OBJECTIVE
  The objective of this study was to determine the simultaneous changes and the correlation between circulating regulatory T (Tregs) and B-cell subsets in normal pregnancy (NP) and pre-eclampsia (PE). Meanwhile, the regulatory function of Tregs on B-cell proliferation was evaluated in vitro.
  
  
  METHODS
  A total of 32 PE and 40 NP women matched for age, gestational age, and parity were included. Using flow cytometry, the percentages of peripheral blood Tregs and B-cell subsets were determined. Moreover, the regulatory function of Tregs on autologous B-cell proliferation in PE and NP was investigated in vitro by flow cytometry and analyzed by modfit software.
  
  
  RESULTS
  The proportions (%) of CD4(+)  Foxp3(+) (P < 0.001) and CD4(+)  CD25(+)  Foxp3(+) (P < 0.01) cells within total CD4(+) T cells were significantly decreased in PE as compared to those of NP. However, no difference was found in CD4(+)  CD25(+) cells in CD4(+) T cell population. CD19(+)  CD27(+) (P < 0.05) and CD19(+)  CD27(+)  IgD(+) (P < 0.01) B cells within CD19(+) B cells (%) in PE were higher than those of NP. Negative correlations between the percentage of CD4(+)  CD25(+)  Foxp3(+) in CD4(+) T cells and that of CD19(+)  CD27(+) (r = -0.384, P < 0.05) and CD19(+)  CD27(+)  IgD(+) (r = -0.402, P < 0.05) in CD19(+) B cells were present in PE but not in NP. Furthermore, the in vitro study demonstrated a significant increase in B-cell proliferation in PE as compared to NP. Tregs in PE were able to suppress the proliferation and precursor frequency of autologous B cells (P < 0.05 each).
  
  
  CONCLUSIONS
  The study indicates that a negative correlation between Tregs and memory B cells is present in women with PE, characterized by a systemic decrease in Tregs and an increase in memory B cells. Although the quantitative deficit of Tregs is present in PE, the Tregs still have a suppressive role in autologous B-cell proliferation.
authors.affiliation: Family Planning Research Institute, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zeng
authors.forename: Joanne
authors.initials: J
authors.lastname: Kwak-Kim
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Ai-Hua
authors.initials: AH
authors.lastname: Liao
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology*; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology*; D011225:Pre-Eclampsia / Q000276:immunology* / Q000473:pathology; D011247:Pregnancy; D011446:Prospective Studies; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
keywords: Memory B cell; pre-eclampsia; pregnancy; regulatory T cell