Project description:Both iron homeostasis and erythropoiesis are known to be affected by aging. Iron needs in mammals are met primarily by iron recycling from senescent red blood cells (RBCs), a task chiefly accomplished by red pulp macrophages (RPMs) in the spleen. Given that RPMs continuously process iron, their cellular functions might be susceptible to age-dependent decline, a possibility that has been unexplored to date. In our project, we identified a formation of undegradable iron- and heme-rich extracellular aggregates in the spleens of 10-11-month-old female mice. To better understand the origin of these aggregates, here, we performed: i) protein identification and intrasample quantification (iBAQ) of proteins of magnetically-isolated red pulp macrophages from spleens of two female 8-weeks-old C57BL/6J (maintained on a standard diet) and ii) label-free quantification of proteins of the splenic protein aggregates formed in the mouse spleen 24 hours after intraperitoneal iron dextran injection, using dextran-injected mice as a control. Two 8-week-old C57BL/6J mice per group were analyzed. This dataset is related to the project PXD032900, which describes quanytitative analysis of proteins in aggregates magnetically isolated from spleen of aged (standard or iron-reduced diet) and young mice (standard diet).
Project description:Gene expression changes in metastasis associated macrophage (MAM) FACS sorted cells from mice bearing pulmonary metastasis of breast tumor cells were compared with lung and spleen resident macrophages sorted from healthy mice using same sorting protocol. A six chip study using total RNA recovered from metastasis associated macrophages from three individual mice and lungs and spleens all from three individual mice. Each chip measures the expression level of 42586 genes.
Project description:Gene expression changes in metastasis associated macrophage (MAM) FACS sorted cells from mice bearing pulmonary metastasis of breast tumor cells were compared with lung and spleen resident macrophages sorted from healthy mice using same sorting protocol.
Project description:The spleen is a conserved secondary lymphoid organ that emerged in parallel to adaptive immunity in early jawed vertebrates. Recent studies have applied single cell transcriptomics to reveal the cellular composition of spleen in several species, cataloguing diverse immune cell types and subpopulations. In this study, 51,119 spleen nuclei transcriptomes were comprehensively investigated in the commercially important teleost Atlantic salmon (Salmo salar L.), contrasting control animals with those challenged with the bacterial pathogen Aeromonas salmonicida. We identified clusters of nuclei representing the expected major cell types, namely T cells, B cells, natural killer-like cells, granulocytes, mononuclear phagocytes, endothelial cells, mesenchymal cells, erythrocytes and thrombocytes. We discovered heterogeneity within several immune lineages, providing evidence for resident macrophages and melanomacrophages, infiltrating monocytes, several candidate dendritic cell subpopulations, and B cells at distinct stages of differentiation, including plasma cells and an igt+ B subset. We provide evidence for twelve candidate T cell subsets, including cd4+ T helper and regulatory T cells, one cd8+ subset, three γδT subsets, and populations double negative for cd4 and cd8. The number of genes showing differential expression during the early stages of infection with Aeromonas was highly variable across cell types, with the largest changes observed in resident macrophages and infiltrating monocytes, followed by resting mature B cells. Our differential expression analysis offers evidence for a strong inflammatory response to bacteria in the spleen driven by macrophages and monocytes, and the recruitment of splenic igt+ B cells to the gut. Overall, this study provides a new cell-resolved perspective of the immune actions of Atlantic salmon spleen, highlighting extensive heterogeneity hidden to bulk transcriptomics. We further provide a large catalogue of cell-specific marker genes that can be leveraged to further explore the function and structural organization of the salmonid immune system.
Project description:To compare the splenic macrophages between SIRPα-knockout mice and WT mice, we performed a complete transcript profiling of the splenic red pulp macrophages from SIRPα-KO mice compared to WT mice using mRNA microarray as a discovery platform. SIRPα-KO mice and WT mice were kept under the same condition. Macrophages were isolated from spleen red pulp of SIRPα-KO mice and WT mice. RNA was then isolated from the same number of freshly isolated macrophages.
Project description:Acute malaria infection with P. chabaudi obliterates embryonically seeded tissue-resident red pulp macrophages in the spleen of C57Bl/6J mice - regardless of whether the infection is mild (mosquito transmitted P. chabaudi AS - no hyperparasitaemia, no measurable clinical manifestations of disease other than low-grade anaemia) or severe (mosquito transmitted P. chabaudi AJ - acute hyperparasitaemia, severe anaemia, hypothermia and prostration). Red pulp macrophages return 100 days later, once mice cleared parasitaemia. We then flow sorted 10,000 red pulp macrophages (lineage-, autofluorescent, F4/80+, B220-, CD11bint, CD11cint) directly into Trizol, extracted total RNA and analysed their transciptome using the affymetrix mouse exon 1.0 ST array. Red pulp macrophages from mice once infected with mild AS or severe AJ P. chabaudi parasites were compared to uninfected age-matched mice. We uncover that red pulp macrophages isolated from the spleens of once-malaria infected mice are transcriptionally identical to prenatally seeded red pulp macrophages from uninfected mice. The spleen tissue niche thus imprints an identical functional profile onto these cells - regardless of their origin.
Project description:Adipose-derived mesenchymal stem cells (ASCs) have shown therapeutic potentials against refractory diseases. However, the detailed therapeutic mechanisms remain unclear. Here, we report the therapeutic actions of human ASCs in nephritis, focusing on cellular dynamics and multi-organ networks. Intravenously-administered ASCs accumulated in spleen but not kidneys. Nevertheless, ASCs increased M2 macrophages and Tregs in kidneys and drove strong renoprotection. Splenectomy abolished these therapeutic effects. ASC-derived extracellular vesicles (EVs) were transferred to M2 macrophages, which entered the bloodstream from spleen. EVs induced the transcriptomic signatures of hyperpolarization and PGE2 stimulation in M2 macrophages and ameliorated glomerulonephritis. ASCs, ASC-derived EVs, and EV-transferred M2 macrophages enhanced Treg induction. These findings suggest that EV transfer from spleen-accumulated ASCs to M2 macrophages and subsequent modulation of renal immune-environment underlie the renoprotective effects of ASCs. Our results provide new insights into the therapeutic actions of ASCs, focusing on EV-mediated modulation of macrophages and the spleen-kidney immune network.