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1.
Proc Natl Acad Sci U S A ; 119(32): e2111726119, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914162

RESUMO

A large number of neutrophils infiltrate the lymph node (LN) within 4 h after Staphylococcus aureus skin infection (4 h postinfection [hpi]) and prevent systemic S. aureus dissemination. It is not clear how infection in the skin can remotely and effectively recruit neutrophils to the LN. Here, we found that lymphatic vessel occlusion substantially reduced neutrophil recruitment to the LN. Lymphatic vessels effectively transported bacteria and proinflammatory chemokines (i.e., Chemokine [C-X-C motif] motif 1 [CXCL1] and CXCL2) to the LN. However, in the absence of lymph flow, S. aureus alone in the LN was insufficient to recruit neutrophils to the LN at 4 hpi. Instead, lymph flow facilitated the earliest neutrophil recruitment to the LN by delivering chemokines (i.e., CXCL1, CXCL2) from the site of infection. Lymphatic dysfunction is often found during inflammation. During oxazolone (OX)-induced skin inflammation, CXCL1/2 in the LN was reduced after infection. The interrupted LN conduits further disrupted the flow of lymph and impeded its communication with high endothelial venules (HEVs), resulting in impaired neutrophil migration. The impaired neutrophil interaction with bacteria contributed to persistent infection in the LN. Our studies showed that both the flow of lymph from lymphatic vessels to the LN and the distribution of lymph in the LN are critical to ensure optimal neutrophil migration and timely innate immune protection in S. aureus infection.


Assuntos
Quimiocinas , Infiltração de Neutrófilos , Dermatopatias Bacterianas , Infecções Estafilocócicas , Animais , Quimiocinas/imunologia , Imunidade Inata , Inflamação/patologia , Linfa/imunologia , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/citologia , Dermatopatias Bacterianas/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus
2.
Bull Exp Biol Med ; 172(5): 649-652, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35352258

RESUMO

The histamine content in bioamine-containing cells and the content of NSE+ cells of the lymph nodes were studied in rats in 40 min and in 2 and 4 h after bone marrow allotransplantation by using the cross luminescence-histochemical method and immunohistochemical method, respectively. Within 2 h after allotransplantation of the bone marrow, a significant increase in histamine content in bioamine-containing cells and an increase in the number of NSE+ cells in the period were observed. Both APUD and NSE+ cells were found to be heterogeneous by staining and luminescence.


Assuntos
Transplante de Medula Óssea , Histamina , Linfonodos , Animais , Células da Medula Óssea , Linfonodos/citologia , Neurônios , Fosfopiruvato Hidratase , Ratos
3.
J Virol ; 96(7): e0025522, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35311550

RESUMO

CD8 T cells are key players in the clearance of human immunodeficiency virus (HIV)-infected cells, such that CD8 T-cell dysfunction contributes to viral persistence despite antiretroviral (ARV) therapy. Mesenteric lymph nodes (MLNs) are major sites of gut mucosal immunity. While different CD8 T cell subsets such as CD8 alpha-alpha (CD8αα), CD8 alpha-beta (CD8αß), CD8 regulatory T cells (Treg), and mucosa-associated invariant T cells (MAIT) are present in the gut and exhibit distinct functions, their dynamics remain poorly understood due to the lack of accessibility to these tissues in humans. We thus assessed CD8 T cells in MLNs versus peripheral blood in simian immunodeficiency virus (SIV)-infected rhesus macaques (RMs) following early ARV therapy initiation. SIV infection was associated with an increase over time of both CD8αß and CD8αα T cells in the blood and MLNs, whereas early ARV initiation significantly decreased the frequencies of CD8αα but not CD8αß T cells in MLNs. A significant decrease in the expression of chemokine receptors CCR6 and CXCR3 by CD8 T cells, which are essential for T-cell trafficking to the inflammatory sites, was observed in chronically SIV-infected RMs. Surprisingly, while MAIT cells are increased in ARV-treated RMs, their frequencies in MLN are extremely low and were not impacted by ARV. The acute infection resulted in an early CD39+FoxP3+ CD8 Tregs increase in both compartments, which was normalized after early ARV. Frequencies of CD8 Treg cells were positively correlated with frequencies of CD4 Tregs and accordingly negatively correlated with the Th17/Treg ratio in the blood but not in MLNs. Overall, our results underscore the difference in CD8 T-cell subset dynamics in the blood and MLNs. IMPORTANCE Changes in CD8 T-cell subsets during acute SIV/HIV infections and following early ARV initiation in gut lymphoid tissues are poorly understood. Using an acute SIV infection model in rhesus macaques, we assessed the impact of early ARV, initiated 4 days postinfection, on relative proportions of CD8 T-cell subsets in MLNs compared to blood. We found that acute SIV infection and early ARV initiation differentially affect the distribution of effector CD8 T cells, CD8 MAIT cells, and CD8 Tregs in MLNs compared to blood. Overall, early ARV initiation maintains the frequency of effector CD8 T cells while reducing immunosuppressive CD39+ CD8 Tregs. Our study provides deeper insight into the dynamics of the CD8 T-cell compartment in gut mucosal immune surveillance during acute SIV infection and following early ARV initiation.


Assuntos
Linfócitos T CD8-Positivos , Linfonodos , Síndrome de Imunodeficiência Adquirida dos Símios , Linfócitos T Reguladores , Animais , Antirretrovirais/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Infecções por HIV/imunologia , Linfonodos/citologia , Linfonodos/imunologia , Macaca mulatta , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia , Linfócitos T Reguladores/imunologia
4.
Nat Immunol ; 23(2): 330-340, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35087231

RESUMO

Intravital confocal microscopy and two-photon microscopy are powerful tools to explore the dynamic behavior of immune cells in mouse lymph nodes (LNs), with penetration depth of ~100 and ~300 µm, respectively. Here, we used intravital three-photon microscopy to visualize the popliteal LN through its entire depth (600-900 µm). We determined the laser average power and pulse energy that caused measurable perturbation in lymphocyte migration. Long-wavelength three-photon imaging within permissible parameters was able to image the entire LN vasculature in vivo and measure CD8+ T cells and CD4+ T cell motility in the T cell zone over the entire depth of the LN. We observed that the motility of naive CD4+ T cells in the T cell zone during lipopolysaccharide-induced inflammation was dependent on depth. As such, intravital three-photon microscopy had the potential to examine immune cell behavior in the deeper regions of the LN in vivo.


Assuntos
Microscopia Intravital/métodos , Linfonodos/citologia , Microscopia Confocal/métodos , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Movimento Celular/fisiologia , Rastreamento de Células/métodos , Camundongos
5.
Int J Mol Sci ; 23(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35055188

RESUMO

In a previous study, we uncovered three immune-responsive patterns of gut microbes using an in vitro mesenteric lymph node cell suspension model, abbreviated as the MLN model hereafter. We used Akkermansia muciniphila and Clostridium butyricum as the first group directly inducing an immune response, Bifidobacterium sp. and Bacteroides sp. as the second group evoking an immune response with the help of stimuli (anti-CD3 and anti-CD28 antibodies), and Lactobacillus sp. as the third group blunting the immune response with or without stimuli. Our group previously clarified the immune-activation characteristics of A. muciniphila and linked its in vivo immune induction effect in GF and SPF mice under homeostasis. In the present study, we supplemented the characteristics of C. butyricum and B. bifidum in the in vitro MLN model and addressed the specific elements of the model. Finally, we used an in vivo TNBS-challenge model to show the functional differences between these species with different response patterns in vitro. The results showed that C. butyricum and B. bifidum evoked an immune response in vitro in a dose-dependent and strain-unique manner. Although TLR2, rather than TLR4, is indispensable for immune activation in the present in vitro model, it may not involve interaction between TLR2 and bacterial ligands. Like the PBMC model, the present in vitro MLN model is highly dependent on cell resources and should be given more attention when used to conduct a quantitative comparison. Finally, a mixture of two strong immunogenic strains, A. muciniphila and C. butyricum, significantly increased the mortality of TNBS-challenged (2,4,6-trinitrobenzene sulfonic acid, TNBS) mice, indicating a possible link between the in vitro MLN model and in vivo functional evaluation. However, more evidence is needed to clarify the associations and underlying mechanisms.


Assuntos
Bifidobacterium/imunologia , Clostridium butyricum/imunologia , Linfonodos/citologia , Ácido Trinitrobenzenossulfônico/efeitos adversos , Animais , Técnicas de Cocultura , Linfonodos/imunologia , Linfonodos/microbiologia , Masculino , Mesentério , Camundongos , Modelos Biológicos , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo
6.
Biochem Biophys Res Commun ; 586: 100-106, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837833

RESUMO

Lipopolysaccharide (LPS) is the principal component of the outer membrane of gram-negative bacteria. The prior oral administration of LPS attenuates inflammatory responses, such as intestinal injury and atopic dermatitis, in mouse models; however, the underlying mechanism remains unclear. Here, we examined the effect of topical LPS application on allergic contact dermatitis and its mechanism of action using a murine contact hypersensitivity (CHS) model. Prolonged LPS application to the skin significantly suppressed 2,4-dinitrofluorobenzene (DNFB)-induced CHS. LPS application to the skin also reduced the phagocytosis of fluorescein isothiocyanate (FITC)-dextran by Langerhans and dendritic cells. Cutaneous cell migration into the skin-draining lymph nodes (LNs) induced by FITC painting was reduced by LPS application. During the CHS response, DNFB application induced T-cell proliferation and inflammatory cytokine production in skin-draining LNs, whereas prolonged LPS application inhibited DNFB-induced T-cell growth and interferon gamma production, indicating suppression of DNFB-induced sensitization. These results suggest that prolonged LPS application suppressed DNFB-induced sensitization and subsequently CHS response. Our findings imply that topical application of LPS may prevent allergic dermatitis such as CHS.


Assuntos
Dermatite de Contato/tratamento farmacológico , Fatores Imunológicos/farmacologia , Lipopolissacarídeos/farmacologia , Linfócitos/efeitos dos fármacos , Pele/efeitos dos fármacos , Administração Cutânea , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Dermatite de Contato/etiologia , Dermatite de Contato/imunologia , Dermatite de Contato/patologia , Dextranos/metabolismo , Dinitrofluorbenzeno/administração & dosagem , Orelha , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Células de Langerhans/citologia , Células de Langerhans/efeitos dos fármacos , Células de Langerhans/imunologia , Linfonodos/citologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/citologia , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose/efeitos dos fármacos , Cultura Primária de Células , Pele/imunologia , Pele/patologia
7.
J Feline Med Surg ; 24(2): 77-90, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33908810

RESUMO

OBJECTIVES: Flow cytometric (FCM) immunophenotyping of lymphoid tissue aspirates is an available adjunct for feline lymphoma diagnostics. Reference data have only been established for feline peripheral blood. Studies investigating the composition of normal and mildly reactive feline lymph nodes (LNs) are lacking. The aim of this prospective study was to establish reference data for lymphocyte subpopulations in normal and mildly reactive feline peripheral LNs using a standardised multicolour panel of antibodies. METHODS: Macroscopically inconspicuous mandibular and/or popliteal LNs from 31 adult cats, which were euthanased for reasons other than haematological diseases, were excised and processed within 5 h after death. Multicolour flow cytometry using eight different feline-specific, anti-canine and human cross-reactive monoclonal antibodies used in current diagnostic marker panels was performed after cytological exclusion of pathological states and complemented by lymphocyte clonality testing, histopathology and immunohistochemistry (IHC) to ensure the absence of lymphoid disease. RESULTS: Of 31 cats, the immunophenotyping data of 24 individuals could be included as histopathology and clonality testing excluded a pathological condition. Lymphocyte populations showed the following positive antibody reactions: CD18+ 86.3% ± 13.86%, CD3+ 54.81% ± 11.10%, CD5+ 57.39% ± 12.66%, CD21+ 40.42% ± 12.40%, CD79alphacy+ (CD79αcy) 30.41% ± 13.49% and CD14+ 0.75% ± 1.35%. There were 30.88% ± 13.48% CD4+ and 12.91% ± 6.68% CD8+ cells. Cytology revealed a mixed population of mostly lymphoid cells in all samples. The absence of a monoclonal/oligoclonal neoplastic population was confirmed by lymphocyte clonality testing. Histopathology and IHC showed a normal or mildly reactive pattern in all cases. CONCLUSIONS AND RELEVANCE: This study establishes FCM immunophenotyping data of lymphocyte populations of normal and mildly reactive feline peripheral LNs. For the first time, anti-CD5, CD4, CD8 and CD21 reference data in normal and mildly reactive feline peripheral LNs are presented. CD18, CD3, CD14 and CD79αcy have been used to establish reference data for the first time in any feline material.


Assuntos
Linfonodos , Subpopulações de Linfócitos , Animais , Anticorpos Monoclonais , Gatos , Citometria de Fluxo/veterinária , Imunofenotipagem/veterinária , Linfonodos/citologia , Estudos Prospectivos
8.
STAR Protoc ; 2(4): 100914, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34746869

RESUMO

Most non-Hodgkin's lymphomas grow exclusively in the lymph node compartment protected by the tumor microenvironment. To better understand the cellular heterogeneity and the complex interaction between malignant and non-malignant cells, experiments with primary, patient-derived samples are often indispensable. Here, we describe a time-efficient but gentle protocol to process human lymph node samples. This protocol avoids enzymatic or mechanical stress and was optimized for the purpose of generating single-cell suspension suitable for delicate assays, such as single-cell RNA sequencing. For complete details on the use and execution of this protocol, please refer to Roider et al. (2020).


Assuntos
Linfonodos , Análise de Célula Única/métodos , Células Cultivadas , Citometria de Fluxo , Humanos , Linfonodos/citologia , Linfonodos/patologia , Linfoma não Hodgkin
9.
EMBO J ; 40(22): e108966, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34618370

RESUMO

Viremia in the vertebrate host is a major determinant of arboviral reservoir competency, transmission efficiency, and disease severity. However, immune mechanisms that control arboviral viremia are poorly defined. Here, we identify critical roles for the scavenger receptor MARCO in controlling viremia during arthritogenic alphavirus infections in mice. Following subcutaneous inoculation, arthritogenic alphavirus particles drain via the lymph and are rapidly captured by MARCO+ lymphatic endothelial cells (LECs) in the draining lymph node (dLN), limiting viral spread to the bloodstream. Upon reaching the bloodstream, alphavirus particles are cleared from the circulation by MARCO-expressing Kupffer cells in the liver, limiting viremia and further viral dissemination. MARCO-mediated accumulation of alphavirus particles in the draining lymph node and liver is an important host defense mechanism as viremia and viral tissue burdens are elevated in MARCO-/- mice and disease is more severe. In contrast to prior studies implicating a key role for lymph node macrophages in limiting viral dissemination, these findings exemplify a previously unrecognized arbovirus-scavenging role for lymphatic endothelial cells and improve our mechanistic understanding of viremia control during arthritogenic alphavirus infection.


Assuntos
Infecções por Alphavirus/virologia , Linfonodos/citologia , Receptores Imunológicos/metabolismo , Viremia/patologia , Alphavirus/patogenicidade , Animais , Febre de Chikungunya/genética , Febre de Chikungunya/virologia , Células Endoteliais/virologia , Interações Hospedeiro-Patógeno , Células de Kupffer/virologia , Linfonodos/virologia , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Camundongos Transgênicos , RNA Viral/metabolismo , Receptores Imunológicos/genética , Análise de Célula Única , Viremia/virologia
10.
Front Immunol ; 12: 711980, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34594327

RESUMO

Regulatory B cells (Breg) are considered as immunosuppressive cells. Different subsets of Breg cells have been identified both in human beings and in mice. However, there is a lack of unique markers to identify Breg cells, and the heterogeneity of Breg cells in different organs needs to be further illuminated. In this study, we performed high-throughput single-cell RNA sequencing (scRNA-seq) and single-cell B-cell receptor sequencing (scBCR-seq) of B cells from the murine spleen, liver, mesenteric lymph nodes, bone marrow, and peritoneal cavity to better define the phenotype of these cells. Breg cells were identified based on the expression of immunosuppressive genes and IL-10-producing B (B10) cell-related genes, to define B10 and non-B10 subsets in Breg cells based on the score of the B10 gene signatures. Moreover, we characterized 19 common genes significantly expressed in Breg cells, including Fcrl5, Zbtb20, Ccdc28b, Cd9, and Ptpn22, and further analyzed the transcription factor activity in defined Breg cells. Last, a BCR analysis was used to determine the clonally expanded clusters and the relationship of Breg cells across different organs. We demonstrated that Atf3 may potentially modulate the function of Breg cells as a transcription factor and that seven organ-specific subsets of Breg cells are found. Depending on gene expression and functional modules, non-B10 Breg cells exhibited activated the TGF-ß pathway, thus suggesting that non-B10 Breg cells have specific immunosuppressive properties different from conventional B10 cells. In conclusion, our work provides new insights into Breg cells and illustrates their transcriptional profiles and BCR repertoire in different organs under physiological conditions.


Assuntos
Linfócitos B Reguladores/classificação , Tecido Linfoide/citologia , Análise de Célula Única/métodos , Transcriptoma , Animais , Antígenos de Diferenciação de Linfócitos B/análise , Linfócitos B Reguladores/química , Células da Medula Óssea , Células Clonais , Feminino , Humanos , Imunofenotipagem , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Especificidade de Órgãos , Cavidade Peritoneal/citologia , RNA-Seq , Receptores de Antígenos de Linfócitos B/genética , Baço/citologia , Fatores de Transcrição/análise
11.
Front Immunol ; 12: 749325, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659250

RESUMO

Previous work showed that interferon-λ (IFN-λ) can trigger the synthesis of thymic stromal lymphopoietin (TSLP) by specialized epithelial cells in the upper airways of mice, thereby improving the performance of intranasally administered influenza vaccines. Here we demonstrate that protein-only influenza vaccines containing either IFN-λ or TSLP boosted antigen-specific IgG1 and IgA responses and enhanced the resistance of mice to influenza virus challenge, irrespective of whether the vaccines were applied via the intranasal or the rectal route. TSLP receptor deficiency negatively influenced vaccine-induced antiviral immunity by impairing the migration of dendritic cells from the airways to the draining lymph nodes of immunized mice, thereby restraining follicular helper T cell and germinal center B cell responses. As previously observed during intranasal vaccination, the adjuvant effect of IFN-λ on a rectally administered influenza vaccine was no longer observed when TSLP receptor-deficient mice were used for immunization, highlighting the central role of the IFN-λ/TSLP axis for vaccine-induced antiviral immunity in the mucosa.


Assuntos
Citocinas/administração & dosagem , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Vacinas contra Influenza/administração & dosagem , Interferons/administração & dosagem , Infecções por Orthomyxoviridae/prevenção & controle , Vacinas de Subunidades/administração & dosagem , Administração Intranasal , Administração Retal , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Imunoglobulinas/genética , Vírus da Influenza A , Linfonodos/citologia , Linfonodos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Citocinas/genética
12.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34615710

RESUMO

Lymphocyte-rich classic Hodgkin lymphoma (LR-CHL) is a rare subtype of Hodgkin lymphoma. Recent technical advances have allowed for the characterization of specific cross-talk mechanisms between malignant Hodgkin Reed-Sternberg (HRS) cells and different normal immune cells in the tumor microenvironment (TME) of CHL. However, the TME of LR-CHL has not yet been characterized at single-cell resolution. Here, using single-cell RNA sequencing (scRNA-seq), we examined the immune cell profile of 8 cell suspension samples of LR-CHL in comparison to 20 samples of the mixed cellularity (MC, 9 cases) and nodular sclerosis (NS, 11 cases) subtypes of CHL, as well as 5 reactive lymph node controls. We also performed multicolor immunofluorescence (MC-IF) on tissue microarrays from the same patients and an independent validation cohort of 31 pretreatment LR-CHL samples. ScRNA-seq analysis identified a unique CD4+ helper T cell subset in LR-CHL characterized by high expression of Chemokine C-X-C motif ligand 13 (CXCL13) and PD-1. PD-1+CXCL13+ T cells were significantly enriched in LR-CHL compared to other CHL subtypes, and spatial analyses revealed that in 46% of the LR-CHL cases these cells formed rosettes surrounding HRS cells. MC-IF analysis revealed CXCR5+ normal B cells in close proximity to CXCL13+ T cells at significantly higher levels in LR-CHL. Moreover, the abundance of PD-1+CXCL13+ T cells in the TME was significantly associated with shorter progression-free survival in LR-CHL (P = 0.032). Taken together, our findings strongly suggest the pathogenic importance of the CXCL13/CXCR5 axis and PD-1+CXCL13+ T cells as a treatment target in LR-CHL.


Assuntos
Linfócitos B/metabolismo , Quimiocina CXCL13/metabolismo , Doença de Hodgkin/patologia , Receptores CXCR5/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Antígeno B7-H1/metabolismo , Imunofluorescência , Humanos , Linfonodos/citologia , Receptor de Morte Celular Programada 1/metabolismo , RNA-Seq , Células de Reed-Sternberg/patologia , Análise de Célula Única , Microambiente Tumoral/imunologia
13.
FASEB J ; 35(11): e22017, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34699642

RESUMO

Cellular interactions between endothelial cells and macrophages regulate macrophage localization and phenotype, but the mechanisms underlying these interactions are poorly understood. Here we explored the role of sialoglycans on lymphatic endothelial cells (LEC) in interactions with macrophage-expressed Siglec-1 (CD169). Lectin-binding assays and mass spectrometric analyses revealed that LEC from human skin express more sialylated glycans than the corresponding blood endothelial cells. Higher amounts of sialylated and/or sulfated glycans on LEC than BEC were consistently observed in murine skin, lung and lymph nodes. The floor LEC of the subcapsular sinus (SCS) in murine lymph nodes (LN) displayed sialylated glycans at particularly high densities. The sialoglycans of LN LEC were strongly bound by Siglec-1. Such binding plays an important role in the localization of Siglec-1+ LN-SCS macrophages, as their numbers are strongly reduced in mice expressing a Siglec-1 mutant that is defective in sialoglycan binding. The residual Siglec-1+ macrophages are less proliferative and have a more anti-inflammatory phenotype. We propose that the densely clustered, sialylated glycans on the SCS floor LEC are a key component of the macrophage niche, providing anchorage for the Siglec-1+ LN-SCS macrophages.


Assuntos
Células Endoteliais/metabolismo , Linfonodos/metabolismo , Macrófagos/metabolismo , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Pele/metabolismo , Animais , Células CHO , Cricetulus , Células Endoteliais/citologia , Humanos , Linfonodos/citologia , Macrófagos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Cultura Primária de Células , Pele/citologia
14.
Hum Immunol ; 82(12): 976-981, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34511272

RESUMO

Dendritic cells (DCs) with capacity of antigen cross-presentation are of key interest for immunotherapy against cancer as they can induce antigen-specific cytotoxic T lymphocyte (CTL) responses. This study describes frequencies of DC subtypes in human tonsils and lymph nodes, and phenotypic aspects that may be targeted by adjuvant measures. From human tonsils and neck lymph nodes, DCs were identified through flow cytometry, and subsets of plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) were investigated. Maturity status was assessed and surface receptors with CTL-promoting potentials were studied. CD123+ pDCs as well as CD1c+, CD141+, and CD1c-CD141- mDCs were detected in tonsils and lymph nodes. Both sites featured a similar presence of DC subsets, with CD123+ pDC being dominant and CD141+ mDCs least frequent. Based on CD80/CD86 expression, all DC subtypes featured a low degree of maturation. Expression of pattern recognition receptors (PRRs) CD206, CD207, DC-SIGN, TLR2, and TLR4, as well as the chemokine receptor XCR1, indicated DC subset-specific receptor profiles. We conclude that tonsils and lymph nodes share common features in terms of DC subset frequency and maturation as well as PRR and XCR1 expression pattern. Our work suggests that both sites may be considered for vaccine deposition in DC-mediated immunotherapy.


Assuntos
Células Dendríticas/metabolismo , Linfonodos/citologia , Tonsila Palatina/citologia , Receptores de Reconhecimento de Padrão/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Antígenos CD40/metabolismo , Células Dendríticas/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Acoplados a Proteínas G/metabolismo , Adulto Jovem
15.
Nature ; 597(7875): 250-255, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34497389

RESUMO

The cellular landscape of the human intestinal tract is dynamic throughout life, developing in utero and changing in response to functional requirements and environmental exposures. Here, to comprehensively map cell lineages, we use single-cell RNA sequencing and antigen receptor analysis of almost half a million cells from up to 5 anatomical regions in the developing and up to 11 distinct anatomical regions in the healthy paediatric and adult human gut. This reveals the existence of transcriptionally distinct BEST4 epithelial cells throughout the human intestinal tract. Furthermore, we implicate IgG sensing as a function of intestinal tuft cells. We describe neural cell populations in the developing enteric nervous system, and predict cell-type-specific expression of genes associated with Hirschsprung's disease. Finally, using a systems approach, we identify key cell players that drive the formation of secondary lymphoid tissue in early human development. We show that these programs are adopted in inflammatory bowel disease to recruit and retain immune cells at the site of inflammation. This catalogue of intestinal cells will provide new insights into cellular programs in development, homeostasis and disease.


Assuntos
Envelhecimento , Sistema Nervoso Entérico/citologia , Feto/citologia , Saúde , Intestinos/citologia , Intestinos/crescimento & desenvolvimento , Linfonodos/citologia , Linfonodos/crescimento & desenvolvimento , Adulto , Animais , Criança , Doença de Crohn/patologia , Conjuntos de Dados como Assunto , Sistema Nervoso Entérico/anatomia & histologia , Sistema Nervoso Entérico/embriologia , Sistema Nervoso Entérico/crescimento & desenvolvimento , Células Epiteliais/citologia , Feminino , Feto/anatomia & histologia , Feto/embriologia , Humanos , Intestinos/embriologia , Intestinos/inervação , Linfonodos/embriologia , Linfonodos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Organogênese , Receptores de IgG/metabolismo , Transdução de Sinais , Análise Espaço-Temporal , Fatores de Tempo
16.
Elife ; 102021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34402793

RESUMO

Follicular T helper cells (Tfh) are a specialized subset of CD4 effector T cells that are crucial for germinal center (GC) reactions and for selecting B cells to undergo affinity maturation. Despite this central role for humoral immunity, only few data exist about their clonal distribution when multiple lymphoid organs are exposed to the same antigen (Ag) as it is the case in autoimmunity. Here, we used an autoantibody-mediated disease model of the skin and injected one auto-Ag into the two footpads of the same mouse and analyzed the T cell receptor (TCR)ß sequences of Tfh located in GCs of both contralateral draining lymph nodes. We found that over 90% of the dominant GC-Tfh clonotypes were shared in both lymph nodes but only transiently. The initially dominant Tfh clonotypes especially declined after establishment of chronic disease while GC reaction and autoimmune disease continued. Our data demonstrates a dynamic behavior of Tfh clonotypes under autoimmune conditions and emphasizes the importance of the time point for distinguishing auto-Ag-specific Tfh clonotypes from potential bystander activated ones.


Assuntos
Autoanticorpos/imunologia , Autoimunidade/imunologia , Centro Germinativo/imunologia , Linfonodos/imunologia , Células T Auxiliares Foliculares/imunologia , Animais , Antígenos/administração & dosagem , Antígenos/imunologia , Linfócitos B/imunologia , Feminino , Imunidade Humoral , Imunização , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos C57BL
17.
Hum Exp Toxicol ; 40(12_suppl): S269-S277, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34424081

RESUMO

Background: Benzo[a]pyrene (BaP) affects the immune system and causes mutagenic and carcinogenic effects. Purpose: We aimed to evaluate the effects of systemic exposure to BaP on mite allergen-induced atopic dermatitis (AD)-like skin lesions in mice. Methods: Mite allergen (Dermatophagoides pteronyssinus; Dp) was injected intradermally into the right ears of NC/Nga male mice on eight occasions every 2-3 days. Benzo[a]pyrene was administered intraperitoneally in the equivalent doses of 0, 2, 20, 200, or 2000 µg/kg/day, once a week on four occasions. Results: AD-like skin inflammation related to mite allergen worsened by BaP exposure at 2, 20 µg/kg/day doses; this was in parallel with eosinophil and mast cell infiltration and mast cell degranulation. A trend was also observed toward increased proinflammatory molecule expression, including macrophage inflammatory protein-1 alpha, interleukin (IL)-4, IL-13, and IL-18, in the ear tissue. However, 200 or 2000 µg/kg/day BaP attenuated the enhancing effects. In the regional lymph nodes, 2 µg/kg/day BaP with Dp enhanced antigen-presenting cell and T cell activation compared with Dp alone. Conclusions: This suggests that BaP exposure can aggravate Dp-induced AD-like skin lesions through TH2-biased responses in the inflamed sites and the activation of regional lymph nodes. Therefore, BaP may be responsible for the recent increase in AD incidence.


Assuntos
Antígenos de Dermatophagoides/toxicidade , Benzo(a)pireno/toxicidade , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/patologia , Animais , Citocinas/genética , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Linfonodos/citologia , Camundongos , Organismos Livres de Patógenos Específicos
18.
Pharmacol Res ; 172: 105811, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34390852

RESUMO

BACKGROUND/AIMS: IR700DX-6T and IR700DX-mbc94 are two chemically synthesized photosensitizers (PSs) that target the translocator protein (TSPO) and type 2 cannabinoid receptor (CB2R), respectively, for photodynamic therapy (PDT) of cancer. Recently, we found that IR700DX-6T and IR700DX-mbc94 exhibited high selectivity and efficiency in PDT for breast cancer and malignant astrocytoma. Yet, the phototherapeutic effects of the PSs on pancreatic cancer and underlying mechanisms remain unknown. This study investigated the effect of IR700DX-6T- or IR700DX-mbc94-PDT on pancreatic cancer and whether the treatment involves eliciting anticancer immune responses in support of superior therapeutic efficacy. METHODS: Four pancreatic cancer cell lines were used for in vitro studies. C57BL/6 mice bearing pancreatic cancer cell-derived xenografts were generated for in vivo studies regarding the therapeutic effects of IR700DX-6T-PDT and IR700DX-mbc94-PDT on pancreatic cancer. The immunostimulatory or immunosuppressive effects of IR700DX-6T-PDT and IR700DX-mbc94-PDT were examined by detecting CD8+ T cells, regulatory T cells (Tregs), and dendritic cells (DCs) using flow cytometry and immunohistochemistry (IHC). RESULTS: TSPO and CB2R were markedly upregulated in pancreatic cancer cells and tissues. Both IR700DX-6T-PDT and IR700DX-mbc94-PDT significantly inhibited pancreatic cancer cell growth in a dose- and time-dependent manner. Notably, assessment of anticancer immune responses revealed that both IR700DX-6T-PDT and IR700DX-mbc94-PDT significantly induced CD8+ T cells, promoted maturation of DCs, and suppressed Tregs, with stronger effects exerted by IR700DX-6T-PDT compared to IR700DX-mbc94-PDT. CONCLUSIONS: IR700DX-6T-PDT and IR700DX-mbc94-PDT involves eliciting anticancer immune responses. Our study has also implicated that PDT in combination with immunotherapy holds promise to improve therapeutic efficacy for patients with pancreatic cancer.


Assuntos
Indóis/uso terapêutico , Compostos de Organossilício/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Trifosfato de Adenosina/metabolismo , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Humanos , Indóis/farmacologia , Linfonodos/citologia , Linfonodos/imunologia , Camundongos Endogâmicos C57BL , Compostos de Organossilício/farmacologia , Pâncreas/metabolismo , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Receptor CB2 de Canabinoide/metabolismo , Receptores de GABA/metabolismo , Baço/citologia , Baço/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia
19.
Pharmacol Res ; 172: 105793, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34339836

RESUMO

To date, the overall response rate to checkpoint blockade remains unsatisfactory, partially due to the limited understanding of the tumor immune microenvironment. The retinoic acid-related orphan receptor γt (RORγt) is the key transcription factor of T helper cell 17 (Th17) cells and plays an essential role in tumor immunity. In this study, we used JG-1, a potent and selective small-molecule RORγt agonist to evaluate the therapeutic potential and mechanism of action of targeting RORγt in tumor immunity. JG-1 promotes Th17 cells differentiation and inhibition of regulatory T (Treg) cells differentiation. JG-1 demonstrates robust tumor growth inhibition in multiple syngeneic models and shows a synergic effect with the Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) antibody. In tumors, JG-1 not only promotes Th17 cells differentiation and increases C-C Motif Chemokine Receptor 6 (CCR6)- Chemokine (C-C motif) ligand 20 (CCL20) expression, but also inhibits both the expression of transforming growth factor-ß1 (TGF-ß1) and the differentiation and infiltration of Treg cells. In summary, JG-1 is a lead compound showing a potent activity in vitro and robust tumor growth inhibition in vivo with synergetic effects with anti-CTLA-4.


Assuntos
Anticorpos/uso terapêutico , Antineoplásicos/uso terapêutico , Antígeno CTLA-4/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Animais , Antineoplásicos/farmacologia , Linfócitos B/efeitos dos fármacos , Antígeno CTLA-4/imunologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Linfonodos/citologia , Camundongos Endogâmicos C57BL , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Baço/citologia , Linfócitos T/efeitos dos fármacos , Fator de Crescimento Transformador beta1/genética
20.
Immunol Lett ; 239: 12-19, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34333043

RESUMO

Colonization factor antigen I (CFA/I) fimbria, an adhesin from enterotoxigenic Escherichia coli, confers protection in murine autoimmune models for type 1 diabetes (T1D), multiple sclerosis, and rheumatoid arthritis. Although CFA/I fimbriae's initial mode of action is in a bystander or in an antigen (Ag)-independent fashion, protection is ultimately dependent upon the induction and/or activation of auto-Ag-specific regulatory T cells (Tregs). However, little is known about how protection transitions from bystander suppression to Ag-specific Tregs. Since dendritic cells (DCs) play an integral role in fate decisions for T cells becoming inflammatory or tolerogenic, the described study tests the hypothesis that Lactococcus lactis expressing CFA/I (LL-CFA/I) stimulates DCs to establish a regulatory microenvironment. To this end, bone marrow-derived dendritic cells (BMDCs) were infected in vitro with LL-CFA/I. Results revealed increased production of IL-10, TGF-ß, and indoleamine 2,3-deoxygenase (IDO). Although co-culture of LL-CFA/I infected BMDCs with naïve T cells did not promote Foxp3 expression, TNF-α and IFN-γ production was suppressed. NOD mice orally dosed with LL-CFA/I showed an increase in regulatory plasmacytoid DCs (pDCs) expressing IDO and TGF-ß in pancreatic lymph nodes (PaLNs) and spleen three days post-treatment. However, Tregs did not appear in the mucosal inductive sites until much later. These findings show that LL-CFA/I influences specific DC populations to establish tolerance.


Assuntos
Células Dendríticas/imunologia , Diabetes Mellitus Tipo 1/prevenção & controle , Lactococcus lactis/imunologia , Probióticos/administração & dosagem , Administração Oral , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Antígenos de Bactérias/metabolismo , Glicemia/análise , Linfócitos T CD4-Positivos , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/metabolismo , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Modelos Animais de Doenças , Feminino , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/imunologia , Proteínas de Fímbrias/metabolismo , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Linfonodos/citologia , Camundongos , Camundongos Transgênicos , Cultura Primária de Células , Baço/citologia , Fator de Crescimento Transformador beta/metabolismo
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