Maternal antibiotic exposure enhances neonatal ILC2 responses and aggravates allergic airway inflammation in adults [ATAC-seq]
Ontology highlight
ABSTRACT: Disruption of circadian rhythm during pregnancy produced adverse health outcomes in offspring. However, the role of maternal circadian rhythms in infants’ immunity and their susceptibility to inflammation remains poorly understood. Here we reported that disruption of circadian rhythms in pregnant mice profoundly aggravated the severity of neonatal inflammatory disorders, including necrotizing enterocolitis (NEC) and sepsis. The diminished production of maternal-derived docosahexaenoic acid (DHA) and the impaired immunosuppressive function of myeloid-derived suppressor cells (MDSCs) in neonates played a dominant role in this process. Mechanistically, DHA enhanced the immunosuppressive function of neonatal MDSCs viaPPARγ mediated mitochondrial oxidative phosphorylation. Transfer of MDSCs or perinatal supplementation of DHA relieved neonatal inflammation induced by maternal rhythms disruption. These observations revealed an important role of maternal circadian rhythms in the control of neonatal inflammation via metabolic reprograming of myeloid cells.
Project description:Disruption of circadian rhythm during pregnancy produced adverse health outcomes in offspring. However, the role of maternal circadian rhythms in infants’ immunity and their susceptibility to inflammation remains poorly understood. Here we reported that disruption of circadian rhythms in pregnant mice profoundly aggravated the severity of neonatal inflammatory disorders, including necrotizing enterocolitis (NEC) and sepsis. The diminished production of maternal-derived docosahexaenoic acid (DHA) and the impaired immunosuppressive function of myeloid-derived suppressor cells (MDSCs) in neonates played a dominant role in this process. Mechanistically, DHA enhanced the immunosuppressive function of neonatal MDSCs viaPPARγ mediated mitochondrial oxidative phosphorylation. Transfer of MDSCs or perinatal supplementation of DHA relieved neonatal inflammation induced by maternal rhythms disruption. These observations revealed an important role of maternal circadian rhythms in the control of neonatal inflammation via metabolic reprograming of myeloid cells.
Project description:The circadian clock is a critical regulator of immunity, and this circadian control of immune modulation plays an essential role in host defense as well as tumor immunosurveillance. Using a single cell RNA-sequencing approach in a genetic model of colorectal cancer (CRC), we identified clock-dependent changes to the immune landscape that dictate the abundance of immunosuppressive cells and consequent suppression of cytotoxic CD8+ T cells. Of these immunosuppressive cell types, PD-L1 expressing myeloid-derived suppressor cells (MDSCs) peak in abundance in a rhythmic manner. Mechanistically, we identified that disruption of the epithelial cell clock regulates the secretion of cytokines and chemokines that promote heightened inflammation, recruitment of neutrophils, and the subsequent development of MDSCs. We leveraged these findings to demonstrate that time-of-day delivery of anti-PD-L1 immunotherapy is most effective when synchronized with the abundance of immunosuppressive MDSCs. Collectively, our results indicate that circadian gating of tumor immunosuppression informs the timing and optimal efficacy of immune checkpoint inhibitors (ICIs).
Project description:Newborns exhibit a heightened vulnerability to inflammatory disorders due to their underdeveloped immune system, yet the underlying mechanisms remain poorly understood. Here we report that plasma spermidine is correlated with the maturity of human newborns and reduced risk of inflammation. Administration of spermidine led to the remission of neonatal inflammation in mice. Mechanistic studies revealed that spermidine enhanced the generation of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) via downstream eIF5A hypusination (eIF5A-Hyp). Genetic deficiency or pharmacological inhibition of deoxyhypusine synthase (DHPS), a key enzyme of eIF5A-Hyp, diminished the immunosuppressive activity of PMN-MDSCs, leading to aggravated neonatal inflammation. The eIF5A-Hyp pathway was found to enhance mitochondrial function via histone acetylation-mediated epigenetic transcription of immunosuppressive signatures in PMN-MDSCs. These findings demonstrated spermidine-eIF5A-Hyp metabolic axis as a master switch to restrict neonatal inflammation.
Project description:Newborns exhibit a heightened vulnerability to inflammatory disorders due to their underdeveloped immune system, yet the underlying mechanisms remain poorly understood. Here we report that plasma spermidine is correlated with the maturity of human newborns and reduced risk of inflammation. Administration of spermidine led to the remission of neonatal inflammation in mice. Mechanistic studies revealed that spermidine enhanced the generation of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) via downstream eIF5A hypusination (eIF5A-Hyp). Genetic deficiency or pharmacological inhibition of deoxyhypusine synthase (DHPS), a key enzyme of eIF5A-Hyp, diminished the immunosuppressive activity of PMN-MDSCs, leading to aggravated neonatal inflammation. The eIF5A-Hyp pathway was found to enhance mitochondrial function via histone acetylation-mediated epigenetic transcription of immunosuppressive signatures in PMN-MDSCs. These findings demonstrated spermidine-eIF5A-Hyp metabolic axis as a master switch to restrict neonatal inflammation.
Project description:Myeloid-derived suppressor cells (MDSCs) are highly immunosuppressive myeloid cells, which increase in cancer patients. The molecular mechanism behind their generation and function is unclear. Whereas granulocytic-MDSCs correlate with poor overall survival in breast cancer, the presence and relevance of monocytic-MDSCs (Mo-MDSCs) is unknown. Here we report for the first time an enrichment of functional blood Mo-MDSCs in breast cancer patients before they acquire a typical Mo-MDSC surface phenotype. A clear population of Mo-MDSCs with the typical cell surface phenotype (CD14+HLA-DRlow/-Co-receptorlow/-) increased significantly first during disease progression and correlated to metastasis to lymph nodes and visceral organs. Furthermore, monocytes, comprising the Mo-MDSC population, from patients with metastatic breast cancer resemble the reprogrammed immunosuppressive monocytes in patients with severe infections, both by their surface and functional phenotype but also at their molecular gene expression profile. Our data suggest that monitoring the Mo-MDSC levels in breast cancer patients may represent a novel and simple biomarker for assessing disease progression. Peripheral blood monocytes were isolated using magnetic cell sorting from 4 patients with metastatic breast cancer, 3 healthy controls, 3 patients with sepsis and 3 patients with active tuberculosis were immediately frozen at -80C in TRIZOL.
Project description:Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that accumulate in the tumor microenvironment of most cancer patients. There MDSCs suppress both adaptive and innate immune responses, hindering immunotherapies. Moreover, many cancers are accompanied by inflammation, a processes that further intensifies MDSC suppressive activity, causing aggressive tumor progression and metastasis. MDSCs collected from tumor-bearing mice profusely release nano-scale membrane-bound extracellular vesicles, called exosomes, which carry biologically active proteins between cells and contribute directly to the immune suppressive functions of MDSC. Many studies on other cell types have shown that exosomes may also carry microRNAs (miRNAs) and messenger RNAs (mRNAs) which can also be transferred to surrounding and distant cells. However, to the best of our knowledge, the miRNA and mRNA cargo of MDSC-derived exosomes has not yet been interrogated. This study aims to identify and quantify the cargo of MDSC and their immunosuppressive exosomes to gather knowledge that can offer insights on the mechanisms by which MDSCs contribute to immune suppression, focusing on the role of exosomes as intercellular communication mediators in the tumor microenvironment. In order to achieve our objective a well-established mouse model based on a conventional mammary carcinoma (4T1 cells) and heightened inflammation (4T1 transduced to express the cytokine interleukin-1b) was used. We provide evidence that MDSC-derived exosomes carry proteins, mRNAs and miRNAs. Relative quantitation demonstrated quantitative differences between the exosome cargo and the cargo of their parental cells, supporting the hypothesis that selective loading into the exosomes is possible. Additionally, quantitative and functional analyses of the exosome cargo generated under conventional and heightened inflammation conditions are consistent with clinical observations that inflammation is linked to cancer development.
Project description:The circadian gene expression in peripheral tissue displays rhythmicity which is reprogrammed by feeding rhythms and dietary composition in mammals. In this study, circadian transcriptome was performed to investigate how maternal circadian rhythms during pregnancy influences circadian gene regulation in the mouse liver.
Project description:This randomized pilot trial studies how well two supportive programs work for improving fatigue and depressive symptoms in patients with GI undergoing chemotherapy. Possible mediators such as psychological stress, circadian disruption, and inflammation, will also be explored.
Project description:The circadian rhythms influence the metabolic activity from molecular level to tissue, organ, and host level. Disruption of the circadian rhythms manifests to the host's health as metabolic syndromes, including obesity, diabetes, and elevated plasma glucose, eventually leading to cardiovascular diseases. Therefore, it is imperative to understand the mechanism behind the relationship between circadian rhythms and metabolism. To start answering this question, we propose a semimechanistic mathematical model to study the effect of circadian disruption on hepatic gluconeogenesis in humans. Our model takes the light-dark cycle and feeding-fasting cycle as two environmental inputs that entrain the metabolic activity in the liver. The model was validated by comparison with data from mice and rat experimental studies. Formal sensitivity and uncertainty analyses were conducted to elaborate on the driving forces for hepatic gluconeogenesis. Furthermore, simulating the impact of Clock gene knockout suggests that modification to the local pathways tied most closely to the feeding-fasting rhythms may be the most efficient way to restore the disrupted glucose metabolism in liver.
Project description:In this study, we used human cortical organoids (hCOs) derived from induced pluripotent stem cells (iPSCs) to examine how hypoxia exposure interferes with astrocyte synapse engulfment at 6 months in culture and 10 months in culture, equivalent to mid fetal- or neonatal-equivalent stages of development, respectively. We identified that hypoxia inhibits the synaptosome engulfment by human astrocytes at both developmental stages, with a more pronounced phenotype in 10 months astrocytes. Transcriptional analyses revealed disruptions in circadian rhythm pathways in hypoxic astrocytes, but not neurons, and PER2 luciferase assays (PER2::LUC) validated the presence of circadian rhythms and their disruption by hypoxia in intact hCOs, with more pronounced rhythms in 10 months hCOs.