Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Transcription profiling of human peripheral monocytes infected with three gram-positive bacterial pathogens (Listeria monocytogenes, Staphylococcus aureus and Streptococcus pneumoniae)

ABSTRACT: Initial transcriptional response of human peripheral monocytes infected with a set of three gram-positive bacterial pathogens (Listeria monocytogenes, Staphylococcus aureus and Streptococcus pneumoniae). Monocytes were isolated from five probands.

ORGANISM(S): Homo sapiens

SUBMITTER: Rohit Ghai

PROVIDER: E-MEXP-1613 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:HOXB4 mediates expansion of adult and embryo-derived hematopoietic stem cells (HSCs) when expressed ectopically. To define the underlying molecular mechanisms, we performed gene expression profiling in combination with subsequent functional analysis using enriched adult HSCs expressing inducible HOXB4. A substantial number of the identified HOXB4 target genes are involved in signaling pathways important for controlling self-renewal, maintenance and differentiation of stem cells. Functional assays performed on selected pathways confirmed the biological coherence of the array results. HOXB4 activity protected adult HSCs from the detrimental effects mediated by the proinflammatory cytokine TNF-alpha. Furthermore, we demonstrate that HOXB4 activity and FGF-signaling are intertwined. HOXB4-mediated expansion of adult HSCs was enhanced by specific and complete inhibition of FGF-receptors. Based on our results we propose that HOXB4 governs pivotal cell-intrinsic pathways involved in the regulation of cell cycle, differentiation and apoptosis. Our results strongly suggest that HOXB4 modulates the response of HSCs to multiple extrinsic signals in a concerted manner, thereby shifting the balance towards stem cell self-renewal. Experiment Overall Design: To understand the mechanisms of HOXB4 activity, we wished to identify target genes of HOXB4 in adult hematopoietic stem and progenitor cells (HSC/HPCs). We thus transduced murine HSC/HPCs with a retroviral vector that co-expresses EGFP and a tamoxifen-inducible form of HOXB4 (HOXB4-ER). Upon addition of 4-hydroxytamoxifen (TMX), the HOXB4-ER fusion protein translocates from the cytoplasm to the nucleus, consequently being capable of modulating gene expression. Transduced cell populations were expanded for 14 days in the presence of TMX. Thereafter, HOXB4-ER+LSK (GFP+ , lineage negative, Sca1+, ckit+) cells were flow cytometrically isolated and cultivated either with or without TMX for 1 or 4 hours. Inactivation of HOXB4 activity by TMX withdrawal was intended to mimic the naturally occurring down-regulation of HOXB4 in differentiating stem cells. RNA was prepared after the aforementioned times and the transcriptional profiles of HOXB4-ER+LSK +/- TMX analyzed using the Affymetrixâ¢ platform. As a control, profiling was also performed with LSK cells expressing unmodified constitutively active HOXB4 (HOXB4const) Â± TMX, to exclude changes in gene expression due to unknown effects of tamoxifen itself. RNAs from adult LSK cells were processed for use on Affymetrix GeneChips Mouse Genome 430 2.0. All quality parameters for the arrays were confirmed to be in the recommended range.

Project description:Ascending bacterial infections of the male genitourinary tract by Escherichia coli are an important cause of male infertility. Thus understanding mechanisms by which immunocompetent cells such as testicular macrophages (TM) respond to infection and how bacterial pathogens manipulate defense pathways is of great relevance. Following infection with uropathogenic E. coli (UPEC) whole genome expression profiling revealed induction of the calcium-dependent nuclear factor of activated T cells (NFAT) signaling pathway in TM as well as in peritoneal macrophages (PM) that were used in comparison. UPEC-dependent NFAT activation was confirmed in cultured TM and in TM using an in vivo infection model. Elevated expression of NFATC2-regulated anti-inflammatory cytokines was found in TM (IL-4, IL-13) and PM (IL-3, IL-4, IL-13). NFATC2 is activated by a rapid influx of calcium caused by the UPEC pore forming toxin alpha-hemolysin. Mutant analysis identified alpha-hemolysin as the main virulent factor responsible for UPEC-dependant suppression of IL-6 and TNF-a cytokine release from PM. Alpha-hemolysin caused differential activation of MAP kinase and AP-1 signaling pathways in TM and PM leading to differential expression profiles of key pro-inflammatory cytokines in PM (IL-1a, IL-1b and IL-6 downregulated) and TM (IL-1b and IL-6 upregulated). In contrast to PM, treatment with lipopolysaccharide did not result in activation of the NFkB pathway in TM as shown by lack of degradation of IkBa and lack of pro-inflammatory cytokine secretion (IL-6, TNF-a). In conclusion, these results propose a mechanism how TM can defend against microbes, while at the same time they are able to maintain the immune privileged status of the testis. 2 Macrophage populations ( peritoneal, testicular) infected with UPEC CFT073; timepoints of mrna harvest at 0 min (control), 30 min and 60 min; of each point 2 biological replicates; of each repliccate 2 technical replicates: summa summarum: 2*((1+1+1)*2*2)=24 samples

Dataset Information

Transcription profiling of human peripheral monocytes infected with three gram-positive bacterial pathogens (Listeria monocytogenes, Staphylococcus aureus and Streptococcus pneumoniae)

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure