B-1a B cells regulate T cell differentiation associated with pregnancy disturbances

• Main Authors: Damian Oscar Muzzio, Rocío eSoldati, Luise eRolle, Marek eZygmunt, Ana Claudia Zenclussen, Federico eJensen
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2014-01-01
• Series: Frontiers in Immunology
• Subjects: Pregnancy; Pregnancy Outcome; Th1 Cells; Th17 Cells; tolerance; regulatory B cells
• Online Access: http://journal.frontiersin.org/Journal/10.3389/fimmu.2014.00006/full

During pregnancy, the maternal immune system faces a double dilemma: tolerate the growing semi-allogeneic fetus and at the same time protect the mother and the progeny against pathogens. This requires a fine and extremely regulated equilibrium between immune activation and tolerance. As professional antigen presenting cells, B cells and in particular B-1a B cells, can activate or tolerize T cells and thus participate in the generation or regulation of immune response.<br/>B-1a B cells were involved in the humoral immune response leading to preeclampsia, one of the main medical complications during pregnancy. Here we demonstrated that B-1a B cells are additionally involved in cellular immune mechanisms associated with pregnancy complications. Using a mouse model of pregnancy disturbances, we showed that B-1a B cells from animals suffering pregnancy disturbances but not from those developing normal pregnancies induce the differentiation of naïve T cells into Th17 and Th1 cells. This differential role of B-1a B cells during pregnancy seems to be associated with the co-stimulatory molecule CD86 as normal pregnant mice showed lower percentages of CD86 expressing B-1a B cells as compared to pregnant mice developing pregnancy disturbances or to non-pregnant animals.<br/>Our data bring to light a new and not explored role of B-1a B cells in the context of pregnancy.<br/>