Project description:Macrophage activation is associated with profound transcriptional reprogramming. Although much progress has been made in the understanding of macrophage activation, polarization and function, the transcriptional programs regulating these processes remain poorly characterized. We stimulated human macrophages with diverse activation signals, acquiring a dataset of 299 macrophage transcriptomes. Analysis of this dataset revealed a spectrum of macrophage activation states extending the current M1 versus M2-polarization model. Network analyses identified central transcriptional regulators associated with all macrophage activation complemented by regulators related to stimulus-specific programs. Applying these transcriptional programs to human alveolar macrophages from smokers and patients with chronic obstructive pulmonary disease (COPD) revealed an unexpected loss of inflammatory signatures in COPD patients. Finally, by integrating murine data from the ImmGen project we propose a refined, activation-independent core signature for human and murine macrophages. This resource serves as a framework for future research into regulation of macrophage activation in health and disease. To better understand active gene regulation in human macrophages during activation and differentiation in vitro with different stimuli ChIP-sequencing experiments were performed. Enrichment patterns of the permissive histone modification mark trimetylation of histone protein 3 (H3K4me3) and macrophage lineage-specific transcription factor PU.1 were analyzed.
Project description:Purified CD11b+, Alveolar macrophage and HDM induced inflammatory DCs from WT and mTOR{delta} APC mice were profiled by RNA-seq to understand mTOR-dependent gene expression
Project description:Bacterial lung infections are associated with strong infiltration of CD11b+ myeloid cells, which limit life-threatening disease, but also severely damage lung tissue. In a murine lung infection model with Streptococcus pneumoniae, we found intrinsic upregulation of CD11b on resident alveolar macrophages. Such CD11b expression was associated with transcriptomic and proteomic adaptations by alveolar macrophages, leading to the identification of specific molecules and pathways that depended on CD11b. In the absence of CD11b, the antimicrobial defense of alveolar macrophages was strongly reduced, and the production of neutrophil-recruiting chemokines was more pronounced. Moreover, CD11b expression limited the infection and prevented excessive alveolar damage. In conclusion, our study provides detailed molecular insights into the alveolar macrophage-specific immune response to Streptococcus pneumoniae lung infection and reveals profound CD11b-dependent alterations that are critical for effective antimicrobial immunity, neutrophil recruitment, and prevention of alveolar damage.
Project description:Botulinum neurotoxin type A (BoNT/A) is one of the most potent protein toxins, which makes it a possible biological weapon and therapeutic. Using microarray analysis we performed global transcriptional profiling of RAW264.7 cells, a murine alveolar macrophage cell line. Time dependent expression profiles after treatment of 1nM or 5nM Botulinum neurotoxin A
Project description:Macrophage activation is associated with profound transcriptional reprogramming. Although much progress has been made in the understanding of macrophage activation, polarization and function, the transcriptional programs regulating these processes remain poorly characterized. We stimulated human macrophages with diverse activation signals, acquiring a dataset of 299 macrophage transcriptomes. Analysis of this dataset revealed a spectrum of macrophage activation states extending the current M1 versus M2-polarization model. Network analyses identified central transcriptional regulators associated with all macrophage activation complemented by regulators related to stimulus-specific programs. Applying these transcriptional programs to human alveolar macrophages from smokers and patients with chronic obstructive pulmonary disease (COPD) revealed an unexpected loss of inflammatory signatures in COPD patients. Finally, by integrating murine data from the ImmGen project we propose a refined, activation-independent core signature for human and murine macrophages. This resource serves as a framework for future research into regulation of macrophage activation in health and disease. Since transcriptional programs are further modulated on several levels including miRNAs we assessed the global spectrum of miRNA expression by miRNA-Seq in macrophages stimulated with IFNM-NM-3, IL4 or with the combination of TNFM-NM-1, PGE2 and P3C
Project description:Resident memory B (BRM) cells develop and persist in the lungs of influenza infected mice and humans but their contribution to recall responses following rechallenge has not been defined. We used scRNA-seq to identify early changes in lung immune cell composition and gene expression following secondary influenza infection and tested the effect of alveolar macrophage depletion (using intranasally delivered CLL). We found an alveolar macrophage dependent upregulation of IFNG-associated pathways after influenza rechallenge, that included increased expression of CXCL9, CXCL10 and CCL5 in myeloid cells.
Project description:Macrophages represent multifunctional leukocytes defined by their stimulus-specific transcriptional reprogramming. As in vivo macrophages are often difficult to obtain, in vitro macrophage models are often used. We aggregated public expression data to define consensus expression profiles for eight commonly-used in vitro macrophage models and built the classifier macIDR, capable of distinguishing macrophage subsets with high accuracy (>0.95). Classification of in vivo macrophages suggested that alveolar macrophages resembled interleukin-10 activated macrophages in general whereas chronic obstructive pulmonary disease patients displayed decreased similarity to interferon-γ stimulated macrophages. Adipose tissue-derived macrophages were classified as unstimulated macrophages, but would resemble LPS-stimulated macrophages more in diabetic-obese patients. Rheumatoid arthritic synovial macrophages were similar to macrophages stimulated with interleukin-10 or interferon-γ. Altogether, our results suggest that macIDR is capable of identifying in vitro macrophages. By projecting in vivo macrophages onto the in vitro macrophages, we were capable of elucidating macrophage-specific changes as a result of tissue and disease.
Project description:Massive reprogramming of the host alveolar macrophage transcriptome occurs during the initial stages of tuberculosis. In bovine tuberculosis, Mcobacterium bovis can persist and replicate within alveolar macrophages through varied mechanisms to subvert or exploit host immune responses ( REF). To determine how these transcriptional changes are regulated we performed ChIPseq analysis of H3K4 and H3K27 methylation, established histone tail markers associated with permissive and repressive chromatin states, respectively. These analyses were carried out in parallel with RNA polymerase II ChIPseq, RNAseq and small non-coding RNAseq. This meta data file refers to the miRNA-seq datasets.
Project description:Massive reprogramming of the host alveolar macrophage transcriptome occurs during the initial stages of tuberculosis. In bovine tuberculosis, Mcobacterium bovis can persist and replicate within alveolar macrophages through varied mechanisms to subvert or exploit host immune responses ( REF). To determine how these transcriptional changes are regulated we performed ChIPseq analysis of H3K4 and H3K27 methylation, established histone tail markers associated with permissive and repressive chromatin states, respectively. These analyses were carried out in parallel with RNA polymerase II ChIPseq, RNAseq and small non-coding RNAseq. This meta data file refers to the RNA-seq datasets.