Project description:Dendritic cells (DCs) and macrophages (MPs) are important for immunological homeostasis in the colon. We found that F4/80hi CX3CR1hi (CD11b+CD103-) cells account for 80% of mouse colonic lamina propria (cLP) MHC-IIhi cells. Both CD11c+ and CD11c- cells within this population were identified as MPs based on multiple criteria, including a MP transcriptome revealed by microarray analysis. These MPs constitutively released high levels of IL-10 at least partially in response to the microbiota via an MyD88-independent mechanism. In contrast, cells expressing low to intermediate levels of F4/80 and CX3CR1 were identified as DCs, based on phenotypic and functional analysis and comprise three separate CD11chi cell populations: CD103+CX3CR1-CD11b- DCs, CD103+CX3CR1-CD11b+ DCs and CD103-CX3CR1intCD11b+ DCs. In non-inflammatory conditions, Ly6Chi monocytes differentiated primarily into CD11c+, but not CD11c- MPs. In contrast, during colitis, Ly6Chi monocytes massively invaded the colon and differentiated into pro-inflammatory CD103-CX3CR1intCD11b+ DCs, which produced high levels of IL-12, IL-23, iNOS and TNF. These findings demonstrate the dual capacity of Ly6Chi blood monocytes to differentiate into either regulatory MPs or inflammatory DCs in the colon, and that the balance of these immunologically antagonistic cell types is dictated by microenvironmental conditions. FACS sorted expression from normal controls
Project description:Dendritic cells (DCs) and macrophages (MPs) are important for immunological homeostasis in the colon. We found that F4/80hi CX3CR1hi (CD11b+CD103-) cells account for 80% of mouse colonic lamina propria (cLP) MHC-IIhi cells. Both CD11c+ and CD11c- cells within this population were identified as MPs based on multiple criteria, including a MP transcriptome revealed by microarray analysis. These MPs constitutively released high levels of IL-10 at least partially in response to the microbiota via an MyD88-independent mechanism. In contrast, cells expressing low to intermediate levels of F4/80 and CX3CR1 were identified as DCs, based on phenotypic and functional analysis and comprise three separate CD11chi cell populations: CD103+CX3CR1-CD11b- DCs, CD103+CX3CR1-CD11b+ DCs and CD103-CX3CR1intCD11b+ DCs. In non-inflammatory conditions, Ly6Chi monocytes differentiated primarily into CD11c+, but not CD11c- MPs. In contrast, during colitis, Ly6Chi monocytes massively invaded the colon and differentiated into pro-inflammatory CD103-CX3CR1intCD11b+ DCs, which produced high levels of IL-12, IL-23, iNOS and TNF. These findings demonstrate the dual capacity of Ly6Chi blood monocytes to differentiate into either regulatory MPs or inflammatory DCs in the colon, and that the balance of these immunologically antagonistic cell types is dictated by microenvironmental conditions.
Project description:In murine large intestinal lamina propria, CX3CR1high resident Mfs possess anti-inflammatory properties and thereby support intestinal homeostasis. Unlike other tissue-resident MΦs, transcription factors that regulate differentiation and function of CX3CR1high MΦs in the large intestine are poorly understood. Thus, to identify transcription factors specifically expressed in CX3CR1high MΦs among large intestinal lamina propria innate myeloid cells, we comprehensively analyzed the genes expression profiles in CX3CR1high MΦs, CX3CR1- CD11b+ CD11c+ cells, CD11b- CD11chigh DCs, and CD11b+CD11c- cells. CD11b- CD11chigh DCs, expressing CD103, in the colon highly expressed transcription factors Batf3, Irf8, and Zbtb46, which have been reported to be required for development of CD103+ DCs. Among four subsets, CX3CR1high macrophages showed the highest expression level of Spic. Transcription factor Spi-C has been reported to be crucial for development of splenic RPMΦs and a fraction of BMMΦs, and thereby contributes to iron recycling.
Project description:Langerhans cells (LCs) populate the mucosal epithelium, a major entry portal for pathogens, yet their ontogeny remains unclear. In contrast to skin LCs originating from self-renewing radioresistant embryonic precursors, we found that oral mucosal LCs derive from circulating radiosensitive precursors. Mucosal LCs can be segregated into CD103+CD11blow (CD103+LCs) and CD11b+CD103- (CD11b+LCs) subsets. We further demonstrated that similar to non-lymphoid dendritic cells (DCs), CD103+LCs originate from pre-DCs, whereas CD11b+LCs differentiate from both pre-DCs and monocytic precursors. Despite this ontogenetic discrepancy between skin and mucosal LCs, transcriptomic signature and immunological function of oral LCs highly resemble those of skin LCs but not DCs. These findings, along with their epithelial position, morphology and expression of LC-associated phenotype strongly suggest that oral mucosal LCs are genuine LCs. Collectively, in a tissue-dependent manner, murine LCs differentiate from at least three distinct precursors (embryonic, pre-DCs and monocytic) in steady state The following cells were isolated from mice (2-4 replicates): Lung DCs, mucosal CD103+ LC, mucosal CD11b+ LC, Skin LC. Transcriptome analysis was performed.
Project description:Dendritic cells (DCs) in tissues and lymphoid organs comprise distinct functional subsets that differentiate in situ from circulating progenitors. Tissue-specific signals that regulate DC subset differentiation are poorly understood. We report that DC-specific deletion of the Notch2 receptor caused a reduction of DC populations in the spleen. Within the splenic CD11b+ DCs, Notch signaling blockade ablated a distinct population marked by high expression of adhesion molecule Esam. The Notch-dependent Esamhi DC subset also required lymphotoxin beta receptor signaling, proliferated in situ and facilitated efficient CD4+ T cell priming. The Notch-independent Esamlo DCs expressed monocyte-related genes and showed superior cytokine responses. In addition, Notch2 deletion led to the loss of CD11b+ CD103+ DCs in the intestinal lamina propria and to the corresponding decrease of IL-17-producing CD4+ T cells in the intestine. Thus,Notch2 is a common differentiation signal for T cell-priming CD11b+ DC subsets in the spleen and intestine. We compared genome-wide expression profiles of wild-type Esam(hi) and Esam(lo) splenic CD11b+ DC populations, along with CD11b+ DCs from DC-RBPJΔ mice. Spleens from 2-3 Cx3cr1-GFP+ RBPJflox/flox CD11c-Cre+ mice or Cx3cr1-GFP+ RBPJflox/flox Cre-negative littermate controls were isolated, pooled and depleted of lymphoid and erythroid cells by negative selection on MACS columns. Live cells were stained for surface expression of CD11c, CD11b and Esam. CD11c(hi) CD11b+ DCs from control mice could be separated into Esam(lo) GFP(hi) versus Esam(hi) GFP(lo) subsets. CD11c(hi) CD11b+ DCs from RBPJ-targeted mice spleens were uniformly Esam(lo) GFP(hi). The two subsets from control mice and single Esam(lo) GFP(hi) subset from RBPJ-targeted mice were sorted using FACSAria II flow sorter and analyzed using GeneChip Mouse Gene 1.0 ST Array (Affymetrix).
Project description:CD103+CD11b+ dendritic cells (DC) are unique to the intestine, but the factors governing their differentiation are unclear. Here we show that transforming growth factor receptor 1 (TGF beta 1) has an indispensable, cell intrinsic role in the development of these cells. Deletion of Tgfbr1 results in markedly fewer intestinal CD103+CD11b+ DCs and a reciprocal increase in the CD103–CD11b+ DC subset. Transcriptional profiling identifies markers that define the CD103+CD11b+ DC lineage, including CD101, TREM1 and Siglec-F, and shows that the absence of CD103+CD11b+ DCs in CD11c-Cre.Tgfbr1fl/fl mice reflects defective differentiation from CD103–CD11b+ intermediaries, rather than an isolated loss of CD103 expression. The defect in CD103+CD11b+ DCs is accompanied by reduced generation of antigen-specific, inducible FoxP3+ regulatory T (Treg) cells in vitro and in vivo, and by reduced numbers of endogenous TH17 cells in the intestinal mucosa. Thus, TGF beta 1 mediated signalling may explain the tissue-specific development of these unique DCs.
Project description:Langerhans cells (LCs) populate the mucosal epithelium, a major entry portal for pathogens, yet their ontogeny remains unclear. In contrast to skin LCs originating from self-renewing radioresistant embryonic precursors, we found that oral mucosal LCs derive from circulating radiosensitive precursors. Mucosal LCs can be segregated into CD103+CD11blow (CD103+LCs) and CD11b+CD103- (CD11b+LCs) subsets. We further demonstrated that similar to non-lymphoid dendritic cells (DCs), CD103+LCs originate from pre-DCs, whereas CD11b+LCs differentiate from both pre-DCs and monocytic precursors. Despite this ontogenetic discrepancy between skin and mucosal LCs, transcriptomic signature and immunological function of oral LCs highly resemble those of skin LCs but not DCs. These findings, along with their epithelial position, morphology and expression of LC-associated phenotype strongly suggest that oral mucosal LCs are genuine LCs. Collectively, in a tissue-dependent manner, murine LCs differentiate from at least three distinct precursors (embryonic, pre-DCs and monocytic) in steady state
Project description:To investigate whether differentially expressed genes induced by SIIN-Q11 were shared between lung CD11b+ and CD103+ DCs, we performed gene expression profiling analysis of lung CD11b+ and CD103+ DCs after intranasal SIIN-Q11.
Project description:Dendritic cells (DCs) are critical in mediating immunity to pathogens, vaccines, tumors and tolerance to self. Significant progress has been made in the study of DC subsets in murine models but the translation of these findings to human DC immunobiology has not been fully realized. Murine splenic CD8+ DC and CD103+ DC possess potent antigen cross-presenting capacity. Although recent evidence points to human blood CD141+ DCs as the functional equivalent of CD8+ DC, the precise identity of the human migratory cross-presenting DC has remained elusive. We performed phenotypic and functional analyses to interrogate the DC compartment of human non-lymphoid tissues and identified three distinct subsets: i) CD141high DCs, ii) CD1c DCs and iii) CD14+ DCs. Only CD141high DCs were capable of cross-presenting soluble antigen. Comparative transcriptome analysis of steady state monocyte and DC subsets between mouse and human confirmed conservation between species, aligning the following subsets together: i) human CD141high DCs with mouse CD8+ and CD103+ DCs, ii) human CD1c+ DCs with mouse CD4+ DCs and iii) human CD14+ DC with mouse monocyte subsets. The lack of positive association between human CD1c+ DCs and mouse non-lymphoid tissue CD11b+ DCs highlights heterogeneity and predicts the existence of a monocyte-like cell within the CD11b+ DCs. Gene expression analysis using total RNA from specific human and mouse monocyte and dendritic cell subsets purified by FACS.