Project description:Transcriptional profiling of primary human alveolar macrophages (AMs) comparing control untreated AMs with AMs exposed with Serotype 14 Streptococcus pneumoniae (NCTC11902) strain (MOI 10) for 4 hours) Two-condition experiment, control AMs vs. infected AMs. Biological replicates: 3 control replicates, 3 infected replicates MOI 10.
Project description:The infected ferrets depleted of alveolar macrophages showed up-regulation of inflammatory related genes compared to the infected ferrets which has alveolar macrophage. There are three group of ferret. One is the infected ferrets depleted of alveolar macrophages. Another is the infected ferret non-depleted of alveolar macrophages. The other is mock
Project description:miR-182 over-expression enhances macrophage resistance to intracellular pathogens. This transcriptional profiling experiment was conducted to identify the basis for protection. Primary human alveolar macrophage-like monocyte derived macrophages were transfected with miR-182 mimic or control RNA, then infected overnight with F. tularensis Live Vaccine Strain at MOI-10 or mock infected.
Project description:Little is known about the relative importance of monocyte and tissue-resident macrophages in the development of lung fibrosis. We show that specific genetic deletion of monocyte-derived alveolar macrophages after their recruitment to the lung ameliorated lung fibrosis, whereas tissue-resident alveolar macrophages did not contribute to fibrosis. Using transcriptomic profiling of flow-sorted cells, we found that monocyte to alveolar macrophage differentiation unfolds continuously over the course of fibrosis and its resolution. During the fibrotic phase, monocyte-derived alveolar macrophages differ significantly from tissue-resident alveolar macrophages in their expression of profibrotic genes. A population of monocyte-derived alveolar macrophages persisted in the lung for one year after the resolution of fibrosis, where they became increasingly similar to tissue-resident alveolar macrophages. Human homologues of profibrotic genes expressed by mouse monocyte-derived alveolar macrophages during fibrosis were up-regulated in human alveolar macrophages from fibrotic compared with normal lungs. Our findings suggest that selectively targeting alveolar macrophage differentiation within the lung may ameliorate fibrosis without the adverse consequences associated with global monocyte or tissue-resident alveolar macrophage depletion.
Project description:Pneumococcal pneumonia is a leading cause of death and a major source of human morbidity. The initial immune response plays a central role in determining the course and outcome of pneumococcal disease. We combine bacterial titer measurements from mice infected with Streptococcus pneumoniae with mathematical modeling to investigate the coordination of immune responses and the effects of initial inoculum on outcome. To evaluate the contributions of individual components, we systematically build a mathematical model from three subsystems that describe the succession of defensive cells in the lung: resident alveolar macrophages, neutrophils and monocyte-derived macrophages. The alveolar macrophage response, which can be modeled by a single differential equation, can by itself rapidly clear small initial numbers of pneumococci. Extending the model to include the neutrophil response required additional equations for recruitment cytokines and host cell status and damage. With these dynamics, two outcomes can be predicted: bacterial clearance or sustained bacterial growth. Finally, a model including monocyte-derived macrophage recruitment by neutrophils suggests that sustained bacterial growth is possible even in their presence. Our model quantifies the contributions of cytotoxicity and immune-mediated damage in pneumococcal pathogenesis.
Project description:Bovine tuberculosis, caused by Mycobacterium bovis, is a disease of considerable economic importance yet comparatively little is known about the bovine immune response to the disease. Alveolar macrophages are one of the first cells to encounter mycobacteria following infection. In this experiment we investigated the early transcriptional response of bovine alveolar macrophages following infection with M. bovis. The transcriptional response to heat-killed M. bovis was also investigated to look for genes that are only differentially transcribed in response to the live organism. Five-condition experiment, uninfected, live and heat-killed M. bovis-infected bovine alveolar macrophages from five cattle infected for two and four hours. Comparisons were within animal. Dye swaps were incorporated into the design.
Project description:Human disease caused by highly pathogenic avian influenza (HPAI) H5N1 can lead to a rapidly progressive viral pneumonia leading to acute respiratory distress syndrome. There is increasing evidence suggests a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. The key target cells for the virus in the lung are the alveolar epithelium and alveolar macrophages, and previous data has shown that compared to seasonal human influenza viruses, equivalent infecting doses of H5N1 viruses markedly up-regulate pro-inflammatory cytokines in both primary cell types in vitro. The dysregulation of H5N1-induced host responses is therefore important for understanding the viral pathogenesis. We used microarrays to analyze and compare the gene expression profiles in primary human macrophages after influenza A virus infection. Peripheral-blood leucocytes were separated from buffy coats of three healthy blood donors and cells were differentiated for 14 days before use. Differentiated macrophages were infected with H1N1 and H5N1 at a multiplicity of infection (MOI) of two. Total RNA was extracted from cells after 1, 3, and 6h post-infection, and gene expression profiling was performed using an Affymetrix Human Gene 1.0 ST microarray platform.