bims-reprim 2021-07-25 papers

Issue of 2021–07–25
three papers selected by
Iva Filipovic, Karolinska Institutet

Immunology. 2021 Jul 20.

Neutrophils in pregnancy: new insights into innate and adaptive immune regulation.

Serena Bert, Eleanor J Ward, Suchita Nadkarni.

The immunology of pregnancy has been the focus of many studies to better understand how the mother is able to tolerate the presence of a semi-allogeneic foetus. Far from the initial view of pregnancy as a state of immunosuppression, successful foetal development from implantation to birth, is now known to be under the control of an intricate balance of immune cells. The balance between pro-inflammatory functions used to promote embryo implantation and placental development and immunosuppressive activity to maintain maternal tolerance of the foetus, is an immunological phenotype unique to pregnancy which is dependent on the time of gestation. Neutrophils are one of a host of innate immune cells detected at the maternal-foetal interface, but very little is known of their function. In this review, we explore the emerging functions of neutrophils during pregnancy and their interactions with and regulation of T cells, a key adaptive immune cell population essential for the establishment of foetal-maternal tolerance.

Keywords: T cells; neutrophils; pregnancy

DOI: https://doi.org/10.1111/imm.13392

Front Immunol. 2021 ;12 688987

Memory B Cells in Pregnancy Sensitization.

Anoma Nellore, John T Killian, Paige M Porrett.

Memory B cells play an important role in immunity to pathogens as these cells are poised to rapidly differentiate into antibody-secreting cells upon antigen re-encounter. Memory B cells also develop over the course of HLA-sensitization during pregnancy and transplantation. In this review, we discuss the potential contribution of memory B cells to pregnancy sensitization as well as the impact of these cells on transplant candidacy and outcomes. We start by summarizing how B cell subsets are altered in pregnancy and discuss what is known about HLA-specific B cell responses given our current understanding of fetal antigen availability in maternal secondary lymphoid tissues. We then review the molecular mechanisms governing the generation and maintenance of memory B cells during infection - including the role of T follicular helper cells - and discuss the experimental evidence for the development of these cells during pregnancy. Finally, we discuss how memory B cells impact access to transplantation and transplant outcomes for a range of transplant recipients.

Keywords: HLA; antibody; memory B cell; pregnancy; sensitization

DOI: https://doi.org/10.3389/fimmu.2021.688987