title: B cell development undergoes profound modifications and adaptations during pregnancy in mice.
abstract: Pregnancy hides an immunological riddle combining two antagonistic characteristics of immunology: the existence of a tolerance that allows the gestation of a semiallogeneic fetus and proper protection against pathogens threatening the health of the immunocompromised mother. Despite the fundamental role that B cells play in orchestrating an immune response, their behavior in the context of pregnancy has been barely investigated. Here we demonstrate that numbers of pre/pro and immature B cells were progressively diminished in the bone marrow (BM) of pregnant mice, leading to a reduced influx of B cells in blood and spleen. Correspondingly, lower levels of B cell-activating factor of the TNF family were observed in serum of pregnant mice. In contrast to immature B cells, mature B cells were accumulated in the BM during pregnancy. Accordingly, higher numbers of mature B cells were observed in the lymph nodes draining the uterus as well as in the peritoneal cavity of pregnant mice, both tissues in close contact with the fetuses. Despite an increase in spleen size, pregnant mice showed lower numbers of splenic B cells, which was mirrored by lower numbers of immature and FO B cells. However, marginal zone B cells in the spleen increased during pregnancy. Additionally, serum IgM, IgA, and IgG3 titers were elevated in pregnant mice. Collectively, our data show how the B cell compartment adapts to the presence of the semiallogeneic fetus during gravidity.
authors.affiliation: Research Laboratory, Department of Obstetrics and Gynecology, University of Greifswald, Greifswald, Germany Experimental Obstetrics and Gynecology Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Damián O
authors.initials: DO
authors.lastname: Muzzio
authors.affiliation: Experimental Obstetrics and Gynecology Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Rocío
authors.initials: R
authors.lastname: Soldati
authors.affiliation: Research Laboratory, Department of Obstetrics and Gynecology, University of Greifswald, Greifswald, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Ehrhardt
authors.affiliation: Institute of Pathology, University of Greifswald, Greifswald, Germany.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Utpatel
authors.affiliation: Institute of Pathology, University of Greifswald, Greifswald, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Evert
authors.affiliation: Experimental Obstetrics and Gynecology Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Zenclussen
authors.affiliation: Research Laboratory, Department of Obstetrics and Gynecology, University of Greifswald, Greifswald, Germany.
authors.forename: Marek
authors.initials: M
authors.lastname: Zygmunt
authors.affiliation: Research Laboratory, Department of Obstetrics and Gynecology, University of Greifswald, Greifswald, Germany Experimental Obstetrics and Gynecology Medical Faculty, Otto-von-Guericke University, Magdeburg, Germany federico.jensen@uni-greifswald.de.
authors.forename: Federico
authors.initials: F
authors.lastname: Jensen
mesh_terms: D000222:Adaptation, Physiological / Q000276:immunology*; D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000502:physiology*; D001854:Bone Marrow Cells / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D005260:Female; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D018655:Lymphocyte Count; D051379:Mice; D008810:Mice, Inbred C57BL; D011247:Pregnancy / Q000097:blood / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000276:immunology
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M
keywords: B cell development; B cell repertoire; autoimmunity; pregnancy; tolerance