Pregnancy imparts distinct systemic adaptive immune function

Abstract

Problem: Pregnancy represents a state of systemic immune activation that is primarily driven by alterations in circulating innate immune cells. Recent studies have suggested that cellular adaptive immune components, T cells and B cells, also undergo changes throughout gestation. However, the phenotypes and functions of such adaptive immune cells are poorly understood. Herein, we utilized high-dimensional flow cytometry and functional assays to characterize T-cell and B-cell responses in pregnant and non-pregnant women. Methods: Peripheral blood mononuclear cells from pregnant (n = 20) and nonpregnant (n = 25) women were used for phenotyping of T-cell and B-cell subsets.T-cell proliferation and B-cell activation were assessed by flow cytometry after in vitro stimulation, and lymphocyte cytotoxicity was evaluated by using a cell-based assay.Statistical comparisons were performed with linear mixed-effects models.Results: Pregnancy was associated with modestly enhanced basal activation of peripheral CD4 + T cells. Both CD4 + and CD8 + T cells from pregnant women showed increased activation-induced proliferation; yet, a reduced proportion of these cells expressed activation markers compared to non-pregnant women. There were no differences in peripheral lymphocyte cytotoxicity between study groups. A greater

Pregnancy-specific responses to COVID-19 revealed by high-throughput proteomics of human plasma

“…Together, these data further demonstrate that, although there is a set of common responses to COVID-19 in both pregnant and non-pregnant state, pregnancy-specific changes are detectable in the maternal circulation. These data put forward evidence for a working hypothesis that pregnancy tailors the immune response against pathogens 29 , 63 , 64 threatening the successful completion of gestation.…”

“…Peripheral T and B cells show decreased numbers, greater activation-induced proliferation, and altered phenotypes during pregnancy 64,111 , and such alterations can be further exacerbated by the lymphopenia that characterizes viral infections such as SARS-CoV-2 35,41,42,112 . Moreover, given the demonstrated relationship between pathological maternal T-cell activation and pregnancy complications such as preterm labor 73,74 , it is imperative that maternal adaptive immunity remain under strict control until normal parturition at term [113][114][115][116] .…”

Pregnancy-specific responses to COVID-19 are revealed by high-throughput proteomics of human plasma

“…Indeed, past and present viral pandemics have provided a large body of evidence showing that specific viruses, such as pandemic influenza viruses, Dengue virus, and coronaviruses, can result in disproportionately high rates of adverse outcomes in pregnant women 99 . Peripheral T and B cells show decreased numbers, greater activation-induced proliferation, and altered phenotypes during pregnancy 100,101 , and such alterations can be further exacerbated by the lymphopenia that characterizes viral infections such as SARS-CoV-2 35,41,43,102 . Moreover, given the demonstrated relationship between pathological maternal T-cell activation and pregnancy complications such as preterm labor 62,63 , it is imperative that maternal adaptive immunity remain under strict control until normal parturition at term [103][104][105][106] .…”

Immune plasticity in pregnancy-associated breast cancer tumorigenesis

“…According to this model, the presence of various immune components [e.g. activated effector T lymphocytes (classified as Th1 and Th2 cells), regulatory T cells (Tregs), and immune checkpoint molecules] alters according to the stage of pregnancy (Demery-Poulos et al ., 2022). Likewise, tumor cells manifest traits of immune suppression extremely analogous to those seen during fetal growth (Rabinovich et al ., 2007).…”