Expression data from in vitro derived dendritic cells generated in the presence of FLT3-L from wt and miR-142-/- BM cells
ABSTRACT: 2 types of dendritic cells (DCs) can be generated in vitro in the presence of Flt3-L: CD4+ equivalent CD24- DCs and CD8+ equivalent CD24+ DCs. miR-142-/- mice show a severe defect in the generation of CD4+ equivalent CD24- DCs. To understand the underlying mechanism, RNA expression was analyzed by Affymetrix microarray from the 2 in vitro subtypes of DCs derived from miR-142+/+ and miR-142-/- bone marrow cells. We used microarrays to detail the global programme of gene expression in the presence or absence of miR-142 in in vitro derived DCs. Bone marrow cells from miR-142+/+ and miR-142-/- C57Bl/6 mice were isolated and incubated in the presence of Flt3-L for 8 days. in vitro derived wt and ko dendritic cells were devided into CD4+ and CD8+ equivalent DCs by FACS and sorted with a FACS-Aria. RNA was isolated and gene expression was investigated
Project description:2 types of dendritic cells (DCs) can be generated in vitro in the presence of Flt3-L: CD4+ equivalent CD24- DCs and CD8+ equivalent CD24+ DCs. miR-142-/- mice show a severe defect in the generation of CD4+ equivalent CD24- DCs. To understand the underlying mechanism, RNA expression was analyzed by Affymetrix microarray from the 2 in vitro subtypes of DCs derived from miR-142+/+ and miR-142-/- bone marrow cells. We used microarrays to detail the global programme of gene expression in the presence or absence of miR-142 in in vitro derived DCs. Bone marrow cells from miR-142+/+ and miR-142-/- C57Bl/6 mice were isolated and incubated in the presence of Flt3-L for 8 days. in vitro derived wt and ko dendritic cells were devided into CD4+ and CD8+ equivalent DCs by FACS and sorted with a FACS-Aria. RNA was isolated and gene expression was investigated
Project description:Mouse and human dendritic cells (DCs) are composed of functionally specialized subsets, but precise interspecies correlation is currently incomplete. Here, we showed that murine lung and gut lamina propria CD11b+ DC populations were comprised of two subsets: FLT3- and IRF4-dependent CD24(+)CD64(-) DCs and contaminating CSF-1R-dependent CD24(-)CD64(+) macrophages. Functionally, loss of CD24(+)CD11b(+) DCs abrogated CD4+ T cell-mediated interleukin-17 (IL-17) production in steady state and after Aspergillus fumigatus challenge. Human CD1c+ DCs, the equivalent of murine CD24(+)CD11b(+) DCs, also expressed IRF4, secreted IL-23, and promoted T helper 17 cell responses. Our data revealed heterogeneity in the mouse CD11b+ DC compartment and identifed mucosal tissues IRF4-expressing DCs specialized in instructing IL-17 responses in both mouse and human. The demonstration of mouse and human DC subsets specialized in driving IL-17 responses highlights the conservation of key immune functions across species and will facilitate the translation of mouse in vivo findings to advance DC-based clinical therapies.
Project description:Analysis of stage-specific gene expression in Zbtb46GFP/+ pre-CD8 DCs, pre-CD4 DCs, CD24 cDCs and CD172a cDCs Bone Marrow and Splenocytes were harvested from 8-10 littermate Zbtb46GFP/+ mice and sorted to >95% purity on the FACS AriaFusion.
Project description:In recent years, porcine dendritic cells (DCs) have been identified from pig tissues. However, studying the interaction of porcine DCs with pathogens is still difficult due to the scarcity of DCs in tissues. In the present work, the Flt3-ligand (Flt3L)-based in vitro derivation system was further characterized and compared with other cytokine derivation models using a combination of factors: stem cell factor (SCF), GM-CSF, and IL-4. The method using Flt3L alone or combined with SCF supported the development of pig bone marrow hematopoietic cells into in vivo equivalent conventional DCs (cDCs). The equivalent cDC1 (the minor population in the cultures) were characterized as CADM1+CD14-MHC-II+CD172a-/lo CD1-CD163- DEC205+CD11R3 lo CD11R1+CD33+CD80/86+. They expressed high levels of FLT3, ZBTB46, XCR1, and IRF8 mRNA, were efficient in endocytosing dextran and in proliferating allogenic CD4+CD8+ T cells, but were deficient in phagocyting inactivated Staphylococcus aureus (S. aureus). Also, after poly I:C stimulation, they predominantly produced IL-12p40a and matured as indicated by the increase of MHC-I, MHC-II, and CD80/86. The equivalent cDC2 (the main population) were CADM1+CD14-MHC-II+C D172a+CD1+CD163-/lo DEC205 lo CD11R3+CD11R1+CD33+CD80/86+; meanwhile, they overexpressed Fc?R1? and IRF4 mRNA. They showed high efficiency in the endocytosis of dextran, but weak in phagocytosing bacteria. They supported allogenic CD4+CD8-/CD4+CD8+ T cell proliferation and were high producers of IL-12p40 (upon TLR7 stimulation) and IL-10 (upon TLR7 stimulation). TLR ligand stimulation also induced their maturation. In addition, a CD14+ population was identified with the phenotype CADM1+CD14+MHC-II+CD172a+ CD1+CD163+DEC205-CD11R3+CD11R1+CD33-/lo CD80/86+. They shared some functional similarities with cDC2 and were distinguishable from macrophages. This CD14+ population was efficient in phagocyting S. aureus but showed less maturation upon TLR ligand stimulation than cDC1 or cDC2. The alternative methods of DC derivation including GM-CSF and/or IL-4 produced mostly CADM1- cells that did not fulfill the canonical phenotype of bona fide porcine DCs. Our study provides an exhaustive characterization of Flt3L-derived DCs with different methods that can help the in vitro study of the interaction of DCs with porcine-relevant pathogens.
Project description:Dendritic cells (DCs) are professional antigen-presenting cells that sample their environment and present antigens to naïve T lymphocytes for the subsequent antigen-specific immune responses. DCs exist in a range of distinct subpopulations including plasmacytoid DCs (pDCs) and classical DCs (cDCs), with the latter consisting of the cDC1 and cDC2 lineages. Although the roles of DC-specific transcription factors across the DC subsets have become understood, the posttranscriptional mechanisms that regulate DC development are yet to be elucidated. MicroRNAs (miRNAs) are pivotal posttranscriptional regulators of gene expression in a myriad of biological processes, but their contribution to the immune system is just beginning to surface. In this study, our in-house probe collection was screened to identify miRNAs possibly involved in DC development and function by targeting the transcripts of relevant mouse transcription factors. Examination of DC subsets from the culture of mouse bone marrow with Flt3 ligand identified high expression of miR-124 which was able to target the transcript of TCF4, a transcription factor critical for the development and homeostasis of pDCs. Further expression profiling of mouse DC subsets isolated from in vitro culture as well as via ex vivo purification demonstrated that miR-124 was outstandingly expressed in CD24(+) cDC1 cells compared to in pDCs and CD172?(+) cDC2 cells. These results imply that miR-124 is likely involved in the processes of DC subset development by posttranscriptional regulation of a transcription factor(s).
Project description:DCs undergo metabolic reprogramming from a predominantly oxidative phosphorylation (OXPHOS) to glycolysis to mount an immunogenic response. The mechanism underpinning the metabolic reprogramming remains elusive. We demonstrate that miRNA-142 (miR-142) is pivotal for this shift in metabolism, which regulates the tolerogenic and immunogenic responses of DCs. In the absence of miR-142, DCs fail to switch from OXPHOS and show reduced production of proinflammatory cytokines and the ability to activate T cells in vitro and in in vivo models of sepsis and alloimmunity. Mechanistic studies demonstrate that miR-142 regulates fatty acid (FA) oxidation, which causes the failure to switch to glycolysis. Loss- and gain-of-function experiments identified carnitine palmitoyltransferase -1a (CPT1a), a key regulator of the FA pathway, as a direct target of miR-142 that is pivotal for the metabolic switch. Thus, our findings show that miR-142 is central to the metabolic reprogramming that specifically favors glycolysis and immunogenic response by DCs.
Project description:The growth factor Flt3 ligand (Flt3L) is central to dendritic cell (DC) homeostasis and development, controlling survival and expansion by binding to Flt3 receptor tyrosine kinase on the surface of DCs. In the context of hematopoietic cell transplantation, Flt3L has been found to suppress graft-versus-host disease (GvHD), specifically <i>via</i> host DCs. We previously reported that the pre-transplant conditioning regimen consisting of bendamustine (BEN) and total body irradiation (TBI) results in significantly reduced GvHD compared to cyclophosphamide (CY)+TBI. Pre-transplant BEN+TBI conditioning was also associated with greater Flt3 expression among host DCs and an accumulation of pre-cDC1s. Here, we demonstrate that exposure to BEN increases Flt3 expression on both murine bone marrow-derived DCs (BMDCs) and human monocyte-derived DCs (moDCs). BEN favors development of murine plasmacytoid DCs, pre-cDC1s, and cDC2s. While humans do not have an identifiable equivalent to murine pre-cDC1s, exposure to BEN resulted in decreased plasmacytoid DCs and increased cDC2s. BEN exposure and heightened Flt3 signaling are associated with a distinct regulatory phenotype, with increased PD-L1 expression and decreased ICOS-L expression. BMDCs exposed to BEN exhibit diminished pro-inflammatory cytokine response to LPS and induce robust proliferation of alloreactive T-cells. These proliferative alloreactive T-cells expressed greater levels of PD-1 and underwent increased programmed cell death as the concentration of BEN exposure increased. Alloreactive CD4<sup>+</sup> T-cell death may be attributable to pre-cDC1s and provides a potential mechanism by which BEN+TBI conditioning limits GvHD and yields T-cells tolerant to host antigen.
Project description:Dendritic cell (DC) are critical initiators and regulators of immunity to pathogens, vaccines, tumors and tolerance to self. Mouse and human dendritic cells (DCs) are comprised of functionally specialized subsets, but precise interspecies correlation is currently incomplete and hampers the full translation of murine findings to human DC-based clinical therapies. In this study, we show that murine lung and gut lamina propria CD11b+ DC populations are comprised of two subsets: FLT3- and IRF4-dependent CD24+CD64- DCs and contaminating CSF-1R-dependent CD24-CD64+ macrophages. CD11b+CD24+CD64- DCs are instrumental in inducing Th17 cell immune response in the steady state and upon Aspergillus fumigatus challenge. We also identified human CD1c+CD11b+ DCs as the functional homologue of mouse mucosal CD11b+ DCs. Our findings highlight the conservation of key immune functions across species and aid the translation of murine studies to human DC immunobiology. The data for the associated human studies have been stored within GSE35459. Gene Expression from total RNA from specific mouse dendritic cell subsets purified by FACS
Project description:The goal of this experiment was to use global gene expression profiling to compare the transcriptomic profiles between the three major types of dendritic cells (DCs) directly isolated ex vivo from the spleen versus derived in vitro from bone marrow FLT3-L cultures. The three DC types analyzed in each condition were type 1 classical DCs (cDC1s), type 2 cDCs (cDC2s) and plasmacytoid DCs (pDCs). The gene expression profiles of the samples of the in vitro derived DCs used here were not reported before. We have previously reported the gene expression profiles of the samples used here for the DCs directly isolated ex vivo from the spleen. They correspond to a reanalysis of the following records: cDC1: GSM1828801 and GSM1828802, cDC2: GSM3178486 and GSM3178487, pDC: GSM2882708 and GSM2882709. Overall design: DCs were generated in vitro from mouse bone marrow FLT3-L cultures and sorted by flow cytometry to over 98% purity, as live, singlet, CD11c+ cells that were SiglecH(+) for eq-pDCs, SIRPα(-/low)CD24(high) for eq-cDC1s and SIRPα(high)CD24(-/low) for eq-cDC2s.
Project description:While miRNAs are increasingly linked to various immune responses, whether they can be targeted for regulating in vivo inflammatory processes such as endotoxin-induced Gram-negative sepsis is not known. Production of cytokines by the dendritic cells (DCs) plays a critical role in response to endotoxin, lipopolysaccharide (LPS). We profiled the miRNA and mRNA of CD11c? DCs in an unbiased manner and found that at baseline, miR-142-3p was among the most highly expressed endogenous miRs while IL-6 was among the most highly expressed mRNA after LPS stimulation. Multiple computational algorithms predicted the IL-6 3' untranslated region (UTR) to be a target of miR-142-3p. Studies using luciferase reporters carrying wild-type (WT) and mutant IL-6 3'UTR confirmed IL-6 as a target for miR-142-3p. In vitro knockdown and overexpression studies demonstrated a critical and specific role for miR142-3p in regulating IL-6 production by the DCs after LPS stimulation. Importantly, treatment of only WT but not the IL-6-deficient (IL-6(?/?)) mice with locked nucleic acid (LNA)-modified phosphorothioate oligonucleotide complementary to miR 142-3p reduced endotoxin-induced mortality. These results demonstrate a critical role for miR-142-3p in regulating DC responses to LPS and provide proof of concept for targeting miRs as a novel strategy for treatment of endotoxin-induced mortality.