Project description:Hypoxemia is a defining feature of acute respiratory distress syndrome (ARDS), an often-fatal complication of pulmonary or systemic inflammation, yet the resulting tissue hypoxia, and its impact on immune responses, is often neglected. Here we showed that ARDS patients were hypoxaemic and monocytopenic within the first 48 hours of ventilation. Monocytopenia was also observed in mouse models of acute lung injury, in which tissue hypoxia drove the suppression of type I interferon signalling in the bone marrow. This impaired monopoiesis, resulted in reduced accumulation of monocyte-derived macrophages and enhanced neutrophil-mediated inflammation in the lung. Administration of CSF1 in mice with hypoxic lung injury rescued the monocytopenia, altered the nature of circulating monocytes, increased monocyte-derived macrophages in the lung and limited injury. Thus, tissue hypoxia altered the dynamics of the immune response to the detriment of the host and interventions to address the aberrant response offer new therapeutic strategies for ARDS.
Project description:We performed a large-scale single cell transcriptomic (scRNA-seq) and epigenomic (snATAC-seq) characterization of cellular subtypes (adipose stromal cells (ASC) and adipocyte nuclei) during inguinal WAT (subcutaneous; iWAT) development in mice, capturing the early postnatal period (postnatal days (PND) 06 and 18) through adulthood (PND56).
Project description:Lung ischemia-reperfusion (I/R) injury remains one of the common complications after various cardiopulmonary surgeries. I-R injury represents one potentially maladaptive response of the innate immune system which is featured by an exacerbated sterile inflammatory response triggered by tissue damage. Thus, understanding the key components and processes involved in sterile inflammation during lung I-R injury is critical to alter care and extend survival for patients with acute lung injury. We constructed a minipig surgical model of transient unilateral left pulmonary artery occlusion without bronchial involvement to create ventilated lung I-R injury. Lung tissues from minipig with sham operation (one sample), left side lung tissues (the operated side)(one sample) and right side lung tissues (the non-operated side)(one sample) from minipig with lung ischemia-reperfusion were submitted for gene expression array analysis.
Project description:Incursions of new pathogenic viruses into humans from animal reservoirs are occurring with alarming frequency. The molecular underpinnings of immune recognition, host responses, and pathogenesis in this setting arepoorly understood. We studied pandemic influenza viruses to determine the mechanism by which increasing glycosylation during evolution of surface proteins facilitates diminished pathogenicity in adapted viruses. ER stressduring infection with poorly glycosylated pandemic strains activated the unfolded protein response, leading to inflammation, acute lung injury, and mortality. Seasonal strains or viruses engineered to mimic adapted viruses displaying excess glycans on the hemagglutinin did not cause ER stress, allowing preservation of the lungs and survival. We propose that ER stress resultingfrom recognition of non-adapted viruses is utilized to discriminate “non-self” at the level of protein-processing and to activate immune responses, with unintended consequences on pathogenesis. Understanding this mechanism should improve strategies for treating acute lung injury from zoonotic viral infections. Lung transcription analysis of Influenza A virus infected mice.
Project description:Analysis of transcriptional profile of lung resident macrophages during acute and resolution phase of LPS inhalation induced lung injury. Because macrophages coordinate both the induction and resolution of inflammatory lung injury, we examined the transcriptional signatures of resident lung macrophages isolated from LysM-GFP mice during baseline (0h), peak of injury (4h), and during the resolution phase (24h).
Project description:Alveolar epithelial type 2 (AT2) cells are facultative progenitor cells that drive adult alveolar regeneration after acute lung injury. Using transcriptomic analyses from in vivo mouse injury models, we define the role of Tfcp2l1 in regulating AT2 cell behavior during lung regeneration.
