Iron is an essential component of the erythrocyte protein hemoglobin and is crucial to oxygen transport in vertebrates. In the steady state, erythrocyte production is in equilibrium with erythrocyte removal1. In various pathophysiological conditions, erythrocyte life span is severely compromised, which threatens the organism with anemia and iron toxicity 2,3. Here we identify anon-demand mechanism specific to the liver that clears erythrocytes and recycles iron. We showthat Ly-6Chigh monocytes ingest stressed and senescent erythrocytes, accumulate in the liver, and differentiate to ferroportin 1 (FPN1)-expressing macrophages that can deliver iron to hepatocytes. Monocyte-derived FPN1+ Tim-4neg macrophages are transient, reside alongside embryonically-derived Tim-4high Kuppfer cells, and depend on Csf1 and Nrf2. The spleenlikewise recruits iron-loaded Ly-6Chigh monocytes, but they do not differentiate into ironrecycling macrophages due to the suppressive action of Csf2, and are instead shuttled to the livervia coordinated chemotactic cues. Inhibiting this mechanism by preventing monocyte recruitment to the liver leads to kidney failure and liver damage. These observations identify the liver as the primary organ supporting emergency erythrocyte removal and iron recycling, and uncover a mechanism by which the body adapts to fluctuations in erythrocyte integrity.
On-demand erythrocyte disposal and iron recycling requires transient macrophages in the liver.
Specimen part
View SamplesInnate immunity is fundamental to recognition and clearance of bacterial infection. The relevant cells and molecules that orchestrate an effective response, however, remain incompletely understood. Here we describe a previously unknown population of B cells, which we have named innate response activator (IRA) B cells that recognize bacteria directly through TLR-4-MyD88 and protect against polymicrobial sepsis.
Innate response activator B cells protect against microbial sepsis.
Sex, Specimen part, Treatment
View SamplesObesity increases colorectal cancer despite other disturbances. We have used the AOM/DSS protocol to induce colitis-associated cancer in control and IL-6Ra deficient animals. Tumours were microdissected and globalgene expression was analysed using microarray.
Obesity exacerbates colitis-associated cancer via IL-6-regulated macrophage polarisation and CCL-20/CCR-6-mediated lymphocyte recruitment.
Sex, Age, Specimen part
View SamplesAntibody-independent effector functions of B cells, such as antigen presentation and cytokine production, have been shown to play an important role in a variety of immune-mediated conditions such as autoimmune diseases, transplant rejection and graft-versus-host disease. Therapeutic strategies, which interfere with B cell activation could therefore be a useful addition to the current immunosuppressive armamentarium. CD40 is one of the strongest activation stimuli for B cells. The aim of this study was to characterise the gene expression changes that occurr after B cell activation via CD40.
Inhibition of protein geranylgeranylation specifically interferes with CD40-dependent B cell activation, resulting in a reduced capacity to induce T cell immunity.
Specimen part, Subject
View SamplesIL-6 induces IL4ralpha expression in macrophages. This mechanism is necessary to promote macrophage polarization towards an M2-phenotype and is crucial to limit the inflammatory response both upon obesity and LPS-endotoxemia.
Signaling by IL-6 promotes alternative activation of macrophages to limit endotoxemia and obesity-associated resistance to insulin.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
TRIM24 Is an Oncogenic Transcriptional Activator in Prostate Cancer.
Cell line, Treatment
View SamplesIn this experiment we are exploring which genes are regulated by TRIM24 in androgen-dependent and castration-resistant prostate cancer cells.
TRIM24 Is an Oncogenic Transcriptional Activator in Prostate Cancer.
Cell line, Treatment
View SamplesStatins reduce cardiovascular disease risk by lowering plasma low density lipoprotein (LDL)-cholesterol. To identify novel pathways that modulate statin response, we assessed the influence of simvastatin exposure on expression quantitative trait locus (eQTL) associations across the genome in 480 lymphoblastoid cell lines (LCLs). Cell lines were derived blood samples collected ant entry visit from participants in the Cholesterol and Pharmacogenomics (CAP) trial, who underwent a 6 week 40mg/day simvastatin trial. We identified 4590 cis-eQTLS that were independent of treatment status (FDR=1%) and six cis-eQTLS for which there was evidence of an interaction with treatment (FDR=20%). Genotypes and Phenotypes derived from these indivudals are available through dbGaP (Accession Number). eQTL results are available at: http://eqtl.uchicago.edu/cgi=bin/gbrowse/eqtl/
HNRNPA1 regulates HMGCR alternative splicing and modulates cellular cholesterol metabolism.
Sex, Subject
View SamplesRNASeq data from WT, Zmym2 knockout- and Zmym2 overexpressing- E14tg2a mouse embryonic stem cells Overall design: RNASeq of ESCs in medium containing Serum and Leukaemia Inhibitory Factor (LIF)
ZMYM2 inhibits NANOG-mediated reprogramming.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Reprogramming capacity of Nanog is functionally conserved in vertebrates and resides in a unique homeodomain.
Specimen part
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