Genome-wide expression study of the CD11b+ subsets of dermal myeloid cells and their migratory counterparts in the draining lymph node
Ontology highlight
ABSTRACT: Numerous CD11b+ myeloid cells are present within the dermis. They are very heterogeneous and can be divided in dermal DCs, tissue monocytes and tissue macrophages. At steady state, only CD11b+ DC migrate from the dermis to the skin draining lymph nodes whereas upon DNFB-induced inflammation, CD11b+ DC as well as dermal monocytes migrated to the lymph nodes. The objective of this study was to use gene expression profiling to rigorously identify the different subsets of dermal CD11b+ myeloid cells at steady state and upon inflammation and to characterize their functional potential. This study includes data from DC, monocytes and macrophages purified by flow cytometry sorting from the blood (monocytes only), dermis and the cutaneous lymph nodes (migDC and mig mono) of WT C57BL6 mice, under steady-state or upon DNFB-mediated inflammation. Three independent replicates were made for each cell type, from three independent pools of mice, and were hybridized on 3 separate batches of gene chips Affimetrix 1.0ST.
Project description:Numerous CD11b+ myeloid cells are present within the dermis. They are very heterogeneous and can be divided in dermal DCs, tissue monocytes and tissue macrophages. At steady state, only CD11b+ DC migrate from the dermis to the skin draining lymph nodes whereas upon DNFB-induced inflammation, CD11b+ DC as well as dermal monocytes migrated to the lymph nodes. The objective of this study was to use gene expression profiling to rigorously identify the different subsets of dermal CD11b+ myeloid cells at steady state and upon inflammation and to characterize their functional potential.
Project description:The activity of the potent nasal adjuvant flagellin depends on initial activation of airway epithelilal cells. This study aims at investigating the immune cells involved in the antigen presentation within the respiratory tract. First, microarrays characterized that activation/recruitment of immune cells was the main signature of flagellin activation in lung. Neutrophils and classical monocytes were strongly recruited into the lungs and take up antigen upon nasal administration of flagellin. In contrast, the numbers of lung CD11b+ or CD103+ DC and alveolar macrophages were not enhanced although these cells were very efficient in antigen uptake. Our experiments showed that CD11b+ DC but not monocytes, PMN, CD103+ DC are not essential for the adjuvant effect. Flagellin signaling enhanced the functional activation of lung CD11b+ conventional DC and their migration to the lymph nodes. Using Cd11c-DTR mice, CD11b+ DC from lymph nodes were identified as the major stimulators of CD4 T cell activation. Finally, the migration and maturation of mucosal DC was independent of direct signaling, highlighting the contribution of epithelial factors in the mucosal adjuvant effect of flagellin. In conclusion, these data demonstrate that adjuvant activity can be dissociated from inflammatory cell recruitment an open new perpectives for improvement of vaccines.
Project description:The activity of the potent nasal adjuvant flagellin depends on initial activation of airway epithelilal cells. This study aims at investigating the immune cells involved in the antigen presentation within the respiratory tract. First, microarrays characterized that activation/recruitment of immune cells was the main signature of flagellin activation in lung. Neutrophils and classical monocytes were strongly recruited into the lungs and take up antigen upon nasal administration of flagellin. In contrast, the numbers of lung CD11b+ or CD103+ DC and alveolar macrophages were not enhanced although these cells were very efficient in antigen uptake. Our experiments showed that CD11b+ DC but not monocytes, PMN, CD103+ DC are not essential for the adjuvant effect. Flagellin signaling enhanced the functional activation of lung CD11b+ conventional DC and their migration to the lymph nodes. Using Cd11c-DTR mice, CD11b+ DC from lymph nodes were identified as the major stimulators of CD4 T cell activation. Finally, the migration and maturation of mucosal DC was independent of direct signaling, highlighting the contribution of epithelial factors in the mucosal adjuvant effect of flagellin. In conclusion, these data demonstrate that adjuvant activity can be dissociated from inflammatory cell recruitment an open new perpectives for improvement of vaccines. Female C57BL/6J (6 weeks old) mice were immunized with the TLR5 agonist Flagellin (1μg diluted in PBS) by intranasal (i.n.) administration. Blood samples of four time points post immunization were taken at 2h, 4h, 18h and 48h. Microarray experiments were performed as single-color hybridizations.
Project description:The exit of antigen-presenting cells (APC) and lymphocytes from inflamed skin to afferent lymph is vital for the initiation and maintenance of dermal immune responses. How such exit is achieved and how cells transmigrate the distinct endothelium of lymphatic vessels is however unknown. Here we show that inflammatory cytokines trigger activation of dermal lymphatic endothelial cells (LEC) leading to expression of the key leukocyte adhesion receptors ICAM-1, VCAM-1 and E-selectin, as well as a discrete panel of chemokines and other potential regulators of leukocyte transmigration. Furthermore, we show that both ICAM-1 and VCAM-1 are induced in the dermal lymphatic vessels of mice exposed to skin contact hypersensitivity where they mediate lymph node trafficking of DC via afferent lymphatics. Lastly, we show that TNF_-stimulates both DC adhesion and transmigration of dermal LEC monolayers in vitro and that the process is efficiently inhibited by ICAM-1 and VCAM-1 adhesion-blocking mAbs. These results reveal a CAM-mediated mechanism for recruiting leukocytes to the lymph nodes in inflammation and highlight the process of lymphatic transmigration as a potential new target for anti-inflammatory therapy. Keywords: TNFalpha, Lymphatic endothelium, induction, Inflammation
Project description:The exit of antigen-presenting cells (APC) and lymphocytes from inflamed skin to afferent lymph is vital for the initiation and maintenance of dermal immune responses. How such exit is achieved and how cells transmigrate the distinct endothelium of lymphatic vessels is however unknown. Here we show that inflammatory cytokines trigger activation of dermal lymphatic endothelial cells (LEC) leading to expression of the key leukocyte adhesion receptors ICAM-1, VCAM-1 and E-selectin, as well as a discrete panel of chemokines and other potential regulators of leukocyte transmigration. Furthermore, we show that both ICAM-1 and VCAM-1 are induced in the dermal lymphatic vessels of mice exposed to skin contact hypersensitivity where they mediate lymph node trafficking of DC via afferent lymphatics. Lastly, we show that TNF_-stimulates both DC adhesion and transmigration of dermal LEC monolayers in vitro and that the process is efficiently inhibited by ICAM-1 and VCAM-1 adhesion-blocking mAbs. These results reveal a CAM-mediated mechanism for recruiting leukocytes to the lymph nodes in inflammation and highlight the process of lymphatic transmigration as a potential new target for anti-inflammatory therapy. Experiment Overall Design: Global gene expression profile of normal dermal lymphatic endothelial cells cultured in media alone (no TNF) compared to that of normal dermal lymphatic endothelial cells stimulated with TNFalpha, 1 ng/ml for 48h.Triplicate biological samples were analyzed from human lymphatic endothelial cells (3 x controls; 3 x TNF treated) and a single sample analyzed from mouse lymphatic endothelial cells (1 x controls; 1 x TNF treated).
Project description:The molecular requirements that guide the differentiation of monocytes into macrophages or monocyte-derived dendritic cells (Mo-DCs) are poorly understood. Here, we demonstrate that the nuclear orphan receptor NR4A3 guides monocyte fate and is essential for Mo-DC differentiation. Nr4a3-/- mice are impaired in the in vivo generation of DC-SIGN+ Mo-DCs following LPS stimulation and, as such, are defective at priming a CD8+ T cell response to gram negative bacteria. We also demonstrate that NR4A3 is an essential downstream effector of IRF4 during in vitro differentiation of Mo-DCs with GM-CSF and IL-4 and that, in absence of NR4A3, monocytes are diverted to macrophages. Our transcriptomic analysis of the genes regulated by NR4A3 reveals that the acquisition of the Mo-DC differentiation program is intertwined with the acquisition of a migratory signature. Furthermore, NR4A3 is critical for steady-state migration of non-lymphoid tissue conventional DCs to lymph nodes. Altogether, our results highlight a unique role for NR4A3 in Mo-DC differentiation and in the acquisition of migratory properties.
Project description:Innate immune cells, including dendritic cells (DCs), monocytes (Mono), macrophages (Mac), natural killer (NK) and innate lymphoid cells (ILC), contribute to chronic inflammation in lymphoid tissues. Here, we characterized the innate immune cell landscape in inflamed mesenteric lymph nodes (MLNs) of patients with inflammatory bowel diseases (IBD) at the single-cell level. CITE-seq analysis unveiled the molecular signature of 11 Mono/Mac/DC (MMDC) and 7 NK/ILC enriched clusters in human MLNs. DC clusters included 3 newly characterized DC clusters: CD1c/CD163/VCAN/CD64-expressing DC3; AXL-expressing DCs; and a CD103+ DC subset, expressing LTB, S100B, and IL22RA2 (encoding IL22BP). Mono/Mac clusters comprised inflammatory monocytes, which accumulated in IBD compared to non-IBD MLNs. Among NK/ILC clusters, we identified a cytotoxic ILC subset (IL7R, KLRD1, GNLY), previously not reported in MLNs, reminiscent of cytotoxic ILC1-like cells found in inflamed gut mucosa.
Project description:Gene expression analysis in lymph nodes and site of injection (intradermal) after vaccination with adenovirus (Ad), modified vaccinia Ankara (MVA) or a mixed formulation of Ad+MVA. The hypothesis tested in the present study was that co-administration of two viral vectors induce a differential gene expression in the site of vaccination (dermis) and the draining lymph nodes that ultimately influences the protective ability of a vaccine against pre-erythrocytic malaria. Total RNA was isolated from the vaccination site (dermis) and lymph nodes after vaccination with adenovirus, MVA or Ad+MVA mixed co-administration after 6h and 24h (ear biopsies) and 9h, 24h and 72h for lymph nodes. Differential gene expression was assessed between vaccinated and non-immunized mice. Four ear biopsy samples did not pass quality control, and are not included in this submission.
Project description:Chemokines and adhesion molecules upregulated in lymphatic endothelial cells (LECs) during tissue inflammation are believed to enhance dendritic cell (DC) migration to draining lymph nodes (dLNs), but the in vivo control of this process is not well understood. By performing transcriptional profiling of LECs isolated from murine skin, we found that inflammation induced by a contact hypersensitivity (CHS) response upregulated the adhesion molecules ICAM-1 and VCAM-1 and inflammatory chemokines in LECs. Furthermore, lymphatic lineage markers like Prox-1, VEGFR3 and LYVE-1 were significantly downregulated during CHS. By contrast, skin inflammation induced by Complete FreundM-bM-^@M-^Ys adjuvant (CFA) induced a different pattern of chemokine and lymphatic marker gene expression and almost no ICAM-1 up-regulation in LECs. In FITC painting experiments, DC migration to dLNs was more strongly increased in CFA- as compared to CHS-induced inflammation. Interestingly, DC migration did not correlate with the induction of CCL21 and ICAM-1 in LECs. However, the requirement for CCR7 signaling became further pronounced during inflammation, whereas CCR7-independent signals only had a minor role in enhancing DC migration. Collectively, these findings indicate that inflammation-induced DC migration is stimulus-dependent and only moderately enhanced by LEC-induced genes other than CCL21. Mouse ear skin single-cell suspensions were prepared by a fast protocol that minimizes the RNA degradation. Fluorescence-activated cell sorting (FACS) was used to sort lymphatic endothelial cells (LEC) from CHS inflammed and control skin. 4 pairs (each with one control and one CHS inflammed sample, sorted and extracted on the same day) of LECs were chosen based on the quality of extracted and amplified material. This gave 8 samples to analyze (4 biological replicates in each condition). Each sample was sorted from 3 mice.
Project description:Antigen presenting dendritic cells (DCs) and monocytes capture and transport antigens from barrier tissues for presentation to antigen-specific T cells in the draining-lymph nodes (LNs). While DCs enter LNs through afferent lymphatics in a CCR7-dependent manner, how exactly antigen-carrying monocytes reach LNs is less clear since monocytes do not express CCR7 and can also enter LNs via the bloodstream. In steady state, and following injection of several PAMPs, scRNA-seq data on LN mononuclear phagocytes identified LN resident versus migratory type 1 and type 2 conventional (c)DCs despite downregulation of DC subset-defining transcripts, such as Xcr1, Clec9a, H2-Ab1, Sirpa, and Clec10a on migratory cDCs. Migratory cDCs gained expression of transcripts controlling cellular migration such as Ccr7, Ccl17, Ccl22, and Ccl5, while migratory monocytes expressed Ccr5 without Ccr7. Using two tracking methods and a gating strategy that clearly distinguishes migratory CD88hiCD26lo monocytes from CD88-CD26hi cDCs, we found that both captured antigens in the lung and migrated to lung-draining LNs. Using global and mixed-chimeric Ccl5-, Ccr2-, Ccr5-, Ccr7-, and Batf3-deficient mice, we found that CCR5+ monocytes follow CCL5-secreting migratory cDCs to reach the draining LN via lymphatic vessels. In a model of asthma, such recruited monocytes regulated the induction of type 2 immunity. Overall, our data suggest that CCL5-secreting migratory cDCs lay down the chemokine trail for CCR5+ antigen-presenting monocytes to reach draining lymph nodes and regulate adaptive immunity.