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1.
Nat Immunol ; 13(10): 947-53, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22922363

RESUMO

Microbiota are essential for weight gain in mouse models of diet-induced obesity (DIO), but the pathways that cause the microbiota to induce weight gain are unknown. We report that mice deficient in lymphotoxin, a key molecule in gut immunity, were resistant to DIO. Ltbr(-/-) mice had different microbial community composition compared to their heterozygous littermates, including an overgrowth of segmented filamentous bacteria (SFB). Furthermore, cecal transplantation conferred leanness to germ-free recipients. Housing Ltbr(-/-) mice with their obese siblings rescued weight gain in Ltbr(-/-) mice, demonstrating the communicability of the obese phenotype. Ltbr(-/-) mice lacked interleukin 23 (IL-23) and IL-22, which can regulate SFB. Mice deficient in these pathways also resisted DIO, demonstrating that intact mucosal immunity guides diet-induced changes to the microbiota to enable obesity.


Assuntos
Imunidade nas Mucosas , Receptor beta de Linfotoxina/fisiologia , Linfotoxina-alfa/fisiologia , Obesidade , Animais , Bactérias/crescimento & desenvolvimento , Bactérias/imunologia , Ceco/microbiologia , Ceco/transplante , Dieta , Metabolismo Energético , Vida Livre de Germes , Interleucina-23/deficiência , Interleucina-23/fisiologia , Interleucinas/deficiência , Interleucinas/fisiologia , Receptor beta de Linfotoxina/genética , Linfotoxina-alfa/deficiência , Linfotoxina-alfa/genética , Metagenoma , Camundongos , Camundongos Knockout , Obesidade/etiologia , Obesidade/imunologia , Obesidade/metabolismo , Aumento de Peso/imunologia , Interleucina 22
2.
Int J Mol Sci ; 25(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38396724

RESUMO

The development of new approaches and drugs for effective control of the chronic and complicated forms of urogenital chlamydia caused by Chlamydia trachomatis, which is suspected to be one of the main causes of infertility in both women and men, is an urgent task. We used the technology of single-domain antibody (nanobody) generation both for the production of targeting anti-chlamydia molecules and for the subsequent acquisition of anti-idiotypic nanobodies (ai-Nbs) mimicking the structure of a given epitope of the pathogen (the epitope of the Chlamydial Type III Secretion System Needle Protein). In a mouse model, we have shown that the obtained ai-Nbs are able to induce a narrowly specific humoral immune response in the host, leading to the generation of intrinsic anti-Chlamydia antibodies, potentially therapeutic, specifically recognizing a given antigenic epitope of Chlamydia. The immune sera derived from mice immunized with ai-Nbs are able to suppress chlamydial infection in vitro. We hypothesize that the proposed method of the creation and use of ai-Nbs, which mimic and present to the host immune system exactly the desired region of the antigen, create a fundamentally new universal approach to generating molecular structures as a part of specific vaccine for the targeted induction of immune response, especially useful in cases where it is difficult to prepare an antigen preserving the desired epitope in its native conformation.


Assuntos
Infecções por Chlamydia , Anticorpos de Domínio Único , Humanos , Camundongos , Animais , Feminino , Epitopos , Sistemas de Secreção Tipo III , Chlamydia trachomatis , Anticorpos Antibacterianos
3.
Immunity ; 32(3): 403-13, 2010 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-20226692

RESUMO

Epithelial cells provide the first line of defense against mucosal pathogens; however, their coordination with innate and adaptive immune cells is not well understood. Using mice with conditional gene deficiencies, we found that lymphotoxin (LT) from innate cells expressing transcription factor RORgammat, but not from adaptive T and B cells, was essential for the control of mucosal C. rodentium infection. We demonstrate that the LTbetaR signaling was required for the regulation of the early innate response against infection. Furthermore, we have revealed that LTbetaR signals in gut epithelial cells and hematopoietic-derived cells coordinate to protect the host from infection. We further determined that LTbetaR signaling in intestinal epithelial cells was required for recruitment of neutrophils to the infection site early during infection via production of CXCL1 and CXCL2 chemokines. These results support a model wherein LT from RORgammat(+) cells orchestrates the innate immune response against mucosal microbial infection.


Assuntos
Citrobacter rodentium/imunologia , Infecções por Enterobacteriaceae/imunologia , Células Epiteliais/imunologia , Imunidade Inata , Mucosa Intestinal/imunologia , Receptor beta de Linfotoxina/imunologia , Transdução de Sinais , Imunidade Adaptativa , Animais , Células da Medula Óssea/imunologia , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Receptor beta de Linfotoxina/deficiência , Receptor beta de Linfotoxina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
4.
Cytokine ; 101: 39-47, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27623349

RESUMO

Lymphotoxin (LT) is a member of the tumor necrosis factor (TNF) superfamily of cytokines which serves multiple functions, including the control of lymphoid organ development and maintenance, as well as regulation of inflammation and autoimmunity. Although the role of LT in organogenesis and maintenance of lymphoid organs is well established, the contribution of LT pathway to homeostasis of lymphoid organs during the immune response to pathogens is less understood. In this review, we highlight recent advances on the role of LT pathway in antiviral immune responses. We discuss the role of LT signaling in lymphoid organ integrity, type I IFN production and regulation of protection and immunopathology during viral infections. We further discuss the potential of therapeutic targeting LT pathway for controlling immunopathology and antiviral protection.


Assuntos
Antivirais/imunologia , Tecido Linfoide/fisiologia , Linfotoxina-alfa/imunologia , Viroses/imunologia , Animais , Autoimunidade , Homeostase/imunologia , Humanos , Inflamação , Interferon Tipo I/biossíntese , Interferon Tipo I/imunologia , Tecido Linfoide/imunologia , Receptor beta de Linfotoxina/imunologia , Linfotoxina-alfa/efeitos dos fármacos , Linfotoxina-alfa/genética , Camundongos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/fisiologia , Viroses/tratamento farmacológico , Viroses/fisiopatologia
5.
PLoS Pathog ; 10(5): e1004142, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24854422

RESUMO

Septic pneumonias resulting from bacterial infections of the lung are a leading cause of human death worldwide. Little is known about the capacity of CD8 T cell-mediated immunity to combat these infections and the types of effector functions that may be most effective. Pneumonic plague is an acutely lethal septic pneumonia caused by the Gram-negative bacterium Yersinia pestis. We recently identified a dominant and protective Y. pestis antigen, YopE69-77, recognized by CD8 T cells in C57BL/6 mice. Here, we use gene-deficient mice, Ab-mediated depletion, cell transfers, and bone marrow chimeric mice to investigate the effector functions of YopE69-77-specific CD8 T cells and their relative contributions during pulmonary Y. pestis infection. We demonstrate that YopE69-77-specific CD8 T cells exhibit perforin-dependent cytotoxicity in vivo; however, perforin is dispensable for YopE69-77-mediated protection. In contrast, YopE69-77-mediated protection is severely impaired when production of TNFα and IFNγ by CD8 T cells is simultaneously ablated. Interestingly, TNFα is absolutely required at the time of challenge infection and can be provided by either T cells or non-T cells, whereas IFNγ provided by T cells prior to challenge appears to facilitate the differentiation of optimally protective CD8 T cells. We conclude that cytokine production, not cytotoxicity, is essential for CD8 T cell-mediated control of pulmonary Y. pestis infection and we suggest that assays detecting Ag-specific TNFα production in addition to antibody titers may be useful correlates of vaccine efficacy against plague and other acutely lethal septic bacterial pneumonias.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunidade Celular/genética , Interferon gama/fisiologia , Peste/imunologia , Pneumonia Bacteriana/imunologia , Proteínas Citotóxicas Formadoras de Poros/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Yersinia pestis/imunologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Células Cultivadas , Interferon gama/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Peste/complicações , Peste/genética , Pneumonia Bacteriana/genética , Proteínas Citotóxicas Formadoras de Poros/genética , Fator de Necrose Tumoral alfa/genética
6.
Sci Technol Adv Mater ; 17(1): 799-806, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27933119

RESUMO

LaF3/SrF2 multilayer heterostructures with thicknesses of individual layers in the range 5-100 nm have been grown on MgO(100) substrates using molecular beam epitaxy. The longitudinal conductivity of the films has been measured using impedance spectroscopy in the frequency range 10-1-106 Hz and a temperature range 300-570 K. The ionic DC conductivities have been determined from Nyquist impedance diagrams and activation energies from the Arrhenius-Frenkel equation. An increase of the DC conductivity has been observed to accompany decreased layer thickness for various thicknesses as small as 25 nm. The greatest conductivity has been shown for a multilayer heterostructure having thicknesses of 25 nm per layer. The structure has a conductivity two orders of magnitude greater than pure LaF3 bulk material. The increasing conductivity can be understood as a redistribution of charge carriers through the interface due to differing chemical potentials of the materials, by strong lattice-constant mismatch, and/or by formation of a solid La1-xSrxF3-x solution at the interface during the growth process.

7.
Front Immunol ; 15: 1388496, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873613

RESUMO

The intricate immune mechanisms governing mucosal healing following intestinal damage induced by cytotoxic drugs remain poorly understood. The goal of this study was to investigate the role of lymphotoxin beta receptor (LTßR) signaling in chemotherapy-induced intestinal damage. LTßR deficient mice exhibited heightened body weight loss, exacerbated intestinal pathology, increased proinflammatory cytokine expression, reduced IL-22 expression, and proliferation of intestinal epithelial cells following methotrexate (MTX) treatment. Furthermore, LTßR-/-IL-22-/- mice succumbed to MTX treatment, suggesting that LTßR- and IL-22- dependent pathways jointly promote mucosal repair. Although both LTßR ligands LIGHT and LTß were upregulated in the intestine early after MTX treatment, LIGHT-/- mice, but not LTß-/- mice, displayed exacerbated disease. Further, we revealed the critical role of T cells in mucosal repair as T cell-deficient mice failed to upregulate intestinal LIGHT expression and exhibited increased body weight loss and intestinal pathology. Analysis of mice with conditional inactivation of LTßR revealed that LTßR signaling in intestinal epithelial cells, but not in Lgr5+ intestinal stem cells, macrophages or dendritic cells was critical for mucosal repair. Furthermore, inactivation of the non-canonical NF-kB pathway member RelB in intestinal epithelial cells promoted MTX-induced disease. Based on these results, we propose a model wherein LIGHT produced by T cells activates LTßR-RelB signaling in intestinal epithelial cells to facilitate mucosal repair following chemotherapy treatment.


Assuntos
Mucosa Intestinal , Receptor beta de Linfotoxina , Metotrexato , Camundongos Knockout , Transdução de Sinais , Fator de Transcrição RelB , Animais , Mucosa Intestinal/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos dos fármacos , Receptor beta de Linfotoxina/metabolismo , Receptor beta de Linfotoxina/genética , Camundongos , Fator de Transcrição RelB/metabolismo , Fator de Transcrição RelB/genética , Metotrexato/efeitos adversos , Células Epiteliais/metabolismo , Camundongos Endogâmicos C57BL , Interleucina 22 , Interleucinas/metabolismo , Interleucinas/genética
8.
Antibiotics (Basel) ; 13(6)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38927143

RESUMO

In order to combat resistance, it is necessary to develop antimicrobial agents that act differently from conventional antibiotics. Fluorothiazinone, 300 mg tablet (The Gamaleya National Research Center), is an original antibacterial drug based on a new small molecule T3SS and flagellum inhibitor. A total of 357 patients with complicated urinary tract infections (UTIs) were divided into two groups and given Fluorothiazinone 1200 mg/day or a placebo for 7 days to evaluate the efficacy and safety of the drug. Additionally, all patients were given Cefepime 2000 mg/day. Fluorothiazinone with Cefepime showed superiority over placebo/Cefepime based on the assessment of the proportion of patients with an overall outcome in the form of a cure after 21 days post-therapy (primary outcome), overall outcome in cure rates, clinical cure rates, and microbiological efficacy at the end of therapy and after 21 days post-therapy (secondary outcomes). In patients who received Fluorothiazinone, the rate of infection recurrences 53 and 83 days after the end of the therapy was lower by 18.9%, compared with patients who received placebo. Fluorothiazinone demonstrated a favorable safety profile with no serious unexpected adverse events reported. The results showed superiority of the therapy with Fluorothiazinone in combination with Cefepime compared with placebo/Cefepime in patients with cUTIs.

9.
J Appl Genet ; 64(3): 445-458, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37454028

RESUMO

Trihelix transcription factors are involved in the growth and development of plants, as well as various stress responses. In the study presented, we identified 37 trihelix family genes in the apple genome (MdTH). The trihelix genes were located on 13 chromosomes. Phylogenetic analysis of these MdTH and the trihelix genes of other species divided them into six subfamilies: GT-1, GT-2, SH4, SIP1, GTγ, and GTδ. The genes of different groups significantly diverged in their gene structure and conserved functional domains. Cis-element analysis showed that promoter sequences of MdTH genes contained light response elements, phytohormone response elements, and stress-related cis-elements. The expression pattern analysis results demonstrated that MdTH were regulated by drought, salinity, as well as high and low temperatures. MdTH4 and MdTH24 were highly regulated by soil salinity, MdTH4-by drought. MdTH30 showed high expression under low temperature; MdTH8, MdTH20, and MdTH36-under high temperature.


Assuntos
Malus , Malus/genética , Malus/metabolismo , Fatores de Transcrição/genética , Filogenia , Proteínas de Plantas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética
10.
Microorganisms ; 11(2)2023 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-36838426

RESUMO

Mucosal tissue homeostasis is a dynamic process that involves multiple mechanisms including regulation of innate lymphoid cells (ILCs). ILCs are mostly tissue-resident cells which are critical for tissue homeostasis and immune response against pathogens. ILCs can sense environmental changes and rapidly respond by producing effector cytokines to limit pathogen spread and initiate tissue recovery. However, dysregulation of ILCs can also lead to immunopathology. Accumulating evidence suggests that ILCs are dynamic population that can change their phenotype and functions under rapidly changing tissue microenvironment. However, the significance of ILC plasticity in response to pathogens remains poorly understood. Therefore, in this review, we discuss recent advances in understanding the mechanisms regulating ILC plasticity in response to intestinal, respiratory and genital tract pathogens. Key transcription factors and lineage-guiding cytokines regulate this plasticity. Additionally, we discuss the emerging data on the role of tissue microenvironment, gut microbiota, and hypoxia in ILC plasticity in response to mucosal pathogens. The identification of new pathways and molecular mechanisms that control functions and plasticity of ILCs could uncover more specific and effective therapeutic targets for infectious and autoimmune diseases where ILCs become dysregulated.

11.
Front Immunol ; 14: 1146077, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969171

RESUMO

Innate lymphoid cells (ILCs) are heterogeneous innate immune cells which participate in host defense, mucosal repair and immunopathology by producing effector cytokines similarly to their adaptive immune cell counterparts. The development of ILC1, 2, and 3 subsets is controlled by core transcription factors: T-bet, GATA3, and RORγt, respectively. ILCs can undergo plasticity and transdifferentiate to other ILC subsets in response to invading pathogens and changes in local tissue environment. Accumulating evidence suggests that the plasticity and the maintenance of ILC identity is controlled by a balance between these and additional transcription factors such as STATs, Batf, Ikaros, Runx3, c-Maf, Bcl11b, and Zbtb46, activated in response to lineage-guiding cytokines. However, how interplay between these transcription factors leads to ILC plasticity and the maintenance of ILC identity remains hypothetical. In this review, we discuss recent advances in understanding transcriptional regulation of ILCs in homeostatic and inflammatory conditions.


Assuntos
Imunidade Inata , Linfócitos , Diferenciação Celular , Fatores de Transcrição , Citocinas
12.
Blood ; 116(18): 3456-64, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-20634375

RESUMO

Secondary lymphoid organs provide a unique microenvironment for generation of immune responses. Using a cell type-specific conditional knockout approach, we have dissected contributions of tumor necrosis factor (TNF) produced by B cells (B-TNF) or T cells (T-TNF) to the genesis and homeostatic organization of secondary lymphoid organs. In spleen, lymph nodes and Peyer patches, the cellular source of TNF, and its molecular form (soluble versus membrane-bound) appeared distinct. In spleen, in addition to major B-TNF signal, a complementary T-TNF signal contributed to the microstructure. In contrast, B-TNF predominantly controlled the development of follicular dendritic cells and B-cell follicles in Peyer patches. In lymph nodes, cooperation between TNF expressed by B and T cells was necessary for the maintenance of microarchitecture and for generation of an efficient humoral immune response. Unexpectedly, soluble but not membrane TNF expressed by B cells was essential for the organization of the secondary lymphoid organs. Thus, the maintenance of each type of secondary lymphoid organ is orchestrated by distinct contributions of membrane-bound and soluble TNF produced by B and T lymphocytes.


Assuntos
Linfócitos B/imunologia , Linfonodos/imunologia , Nódulos Linfáticos Agregados/imunologia , Baço/imunologia , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Regulação da Expressão Gênica , Imunidade Humoral , Linfonodos/citologia , Linfonodos/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nódulos Linfáticos Agregados/citologia , Baço/citologia , Baço/ultraestrutura , Fator de Necrose Tumoral alfa/genética
13.
J Antibiot (Tokyo) ; 75(3): 155-163, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35064243

RESUMO

The high prevalence of multidrug-resistant Acinetobacter baumannii has emerged as a serious problem in the treatment of nosocomial infections in the past three decades. Recently, we developed a new small-molecule inhibitor belonging to a class of 2,4-disubstituted-4H-[1,3,4]-thiadiazine-5-ones, Fluorothiazinon (FT, previously called CL-55). FT effectively suppressed the T3SS of Chlamydia spp., Pseudomonas aeruginosa, and Salmonella sp. without affecting bacterial growth in vitro. In this study, we describe that prophylactic use of FT for 4 days prior to challenge with resistant clinical isolates of A. baumannii (ABT-897-17 and 52TS19) suppressed septic infection in mice, resulting in improved survival, limited bacteraemia and decreased bacterial load in the organs of the mice. We show that FT had an inhibitory effect on A. baumannii biofilm formation in vitro and, to a greater extent, on biofilm maturation. In addition, FT inhibited Acinetobacter isolate-induced death of HeLa cells, which morphologically manifested as apoptosis. The mechanism of FT action on A. baumannii is currently being studied. FT may be a promising candidate for the development of a broad-spectrum anti-virulence drug to use in the prevention of nosocomial infections.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Anilidas/farmacologia , Antibacterianos/farmacologia , Sepse/tratamento farmacológico , Tiadiazinas/farmacologia , Animais , Carga Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Linhagem Celular Tumoral , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Testes de Sensibilidade Microbiana/métodos , Sepse/metabolismo , Sepse/microbiologia , Virulência/efeitos dos fármacos
14.
Front Cell Infect Microbiol ; 11: 775554, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34938670

RESUMO

Innate lymphoid cells (ILCs) are a heterogeneous group of cytokine-producing lymphocytes which are predominantly located at mucosal barrier surfaces, such as skin, lungs, and gastrointestinal tract. ILCs contribute to tissue homeostasis, regulate microbiota-derived signals, and protect against mucosal pathogens. ILCs are classified into five major groups by their developmental origin and distinct cytokine production. A recently emerged intriguing feature of ILCs is their ability to alter their phenotype and function in response to changing local environmental cues such as pathogen invasion. Once the pathogen crosses host barriers, ILCs quickly activate cytokine production to limit the spread of the pathogen. However, the dysregulated ILC responses can lead to tissue inflammation and damage. Furthermore, the interplay between ILCs and other immune cell types shapes the outcome of the immune response. Recent studies highlighted the important role of ILCs for host defense against intracellular pathogens. Here, we review recent advances in understanding the mechanisms controlling protective and pathogenic ILC responses to intracellular pathogens. This knowledge can help develop new ILC-targeted strategies to control infectious diseases and immunopathology.


Assuntos
Imunidade Inata , Linfócitos , Citocinas , Homeostase , Humanos , Inflamação
15.
J Clin Med ; 10(16)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34442014

RESUMO

BACKGROUND: Motor recovery after stroke is based on neuronal plasticity and the structural reorganization of the brain. Questions are debated about the proper moment to start rehabilitation in the acute period of stroke, the significance of rehabilitation interventions during the so-called "plastic window", and the advantages of modern and traditional programs. The aims of this study were to evaluate the role of different rehabilitation strategies and their combinations for motor recovery and the impact on functional disability by way of neurological and functional outcomes 3 months after ischemic stroke. METHODS: We used three rehabilitation approaches: early rehabilitation from the first day of stroke (Phase I), traditional exercise programs (Phase II), and an author's new method of biofeedback rehabilitation using motion sensors and augmented reality (AR) rehabilitation (Phase III). Clinical and functional outcomes were measured on the 90th day after stroke. We developed algorithms for quantifying the quality of movements during the execution of tasks in the motor domains of the AR rehabilitation program. RESULTS: Phase I of rehabilitation led to an improvement in functional independence, and the recovery of motor functions of the extremities with an absence of mortality and clinical deterioration. AR rehabilitation led to significant improvement both with respect to clinical and functional scores on scales and to variables reflecting the quality of movements. Patients who were actively treated during Phases II and III achieved the same final level of motor recovery and functional outcomes as that of participants who had only received AR rehabilitation during Phase III. Patients who underwent outpatient observation after Phase I showed a deficit of spontaneous motor recovery on the 90th day after stroke. CONCLUSIONS: Early rehabilitation was successful but was not enough; rehabilitation programs should be carried out throughout the entire "sensitive period" of poststroke plasticity. The newly developed AR biofeedback motion training is effective and safe as a separate rehabilitation method in the early recovery period of moderately severe, hemiparalytic, and ischemic stroke. These two rehabilitation approaches must be applied together or after each other, not instead of each other, as shown in clinical practice.

16.
Front Immunol ; 12: 712632, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335629

RESUMO

Lymphotoxin beta receptor (LTßR) is a promising therapeutic target in autoimmune and infectious diseases as well as cancer. Mice with genetic inactivation of LTßR display multiple defects in development and organization of lymphoid organs, mucosal immune responses, IgA production and an autoimmune phenotype. As these defects are imprinted in embryogenesis and neonate stages, the impact of LTßR signaling in adulthood remains unclear. Here, to overcome developmental defects, we generated mice with inducible ubiquitous genetic inactivation of LTßR in adult mice (iLTßRΔ/Δ mice) and redefined the role of LTßR signaling in organization of lymphoid organs, immune response to mucosal bacterial pathogen, IgA production and autoimmunity. In spleen, postnatal LTßR signaling is required for development of B cell follicles, follicular dendritic cells (FDCs), recruitment of neutrophils and maintenance of the marginal zone. Lymph nodes of iLTßRΔ/Δ mice were reduced in size, lacked FDCs, and had disorganized subcapsular sinus macrophages. Peyer`s patches were smaller in size and numbers, and displayed reduced FDCs. The number of isolated lymphoid follicles in small intestine and colon were also reduced. In contrast to LTßR-/- mice, iLTßRΔ/Δ mice displayed normal thymus structure and did not develop signs of systemic inflammation and autoimmunity. Further, our results suggest that LTßR signaling in adulthood is required for homeostasis of neutrophils, NK, and iNKT cells, but is dispensable for the maintenance of polyclonal IgA production. However, iLTßRΔ/Δ mice exhibited an increased sensitivity to C. rodentium infection and failed to develop pathogen-specific IgA responses. Collectively, our study uncovers new insights of LTßR signaling in adulthood for the maintenance of lymphoid organs, neutrophils, NK and iNKT cells, and IgA production in response to mucosal bacterial pathogen.


Assuntos
Envelhecimento/imunologia , Tecido Linfoide/imunologia , Receptor beta de Linfotoxina/fisiologia , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/imunologia , Autoimunidade , Moléculas de Adesão Celular/metabolismo , Quimiocinas/metabolismo , Citrobacter rodentium/imunologia , Cruzamentos Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Homeostase/imunologia , Imunoglobulina A/biossíntese , Imunoglobulina A/imunologia , Inflamação , Células Matadoras Naturais/imunologia , Tecido Linfoide/citologia , Receptor beta de Linfotoxina/biossíntese , Receptor beta de Linfotoxina/deficiência , Receptor beta de Linfotoxina/genética , Camundongos , Camundongos Endogâmicos MRL lpr , Camundongos Transgênicos , Neutrófilos/imunologia , Deleção de Sequência , Organismos Livres de Patógenos Específicos , Esplenomegalia/imunologia
17.
Mucosal Immunol ; 14(3): 703-716, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33214656

RESUMO

Innate lymphoid cells (ILCs) are a heterogeneous family of immune regulators that protect against mucosal pathogens but can also promote intestinal pathology. Although the plasticity between ILCs populations has been described, the role of mucosal pathogens in inducing ILC conversion leading to intestinal pathology remains unclear. Here we demonstrate that IFNγ-producing ILCs are responsible for promoting intestinal pathology in a mouse model of enterocolitis caused by Campylobacter jejuni, a common human enteric pathogen. Phenotypic analysis revealed a distinct population of IFNγ-producing NK1.1-T-bet+ILCs that accumulated in the intestine of C. jejuni-infected mice. Adoptive transfer experiments demonstrated their capacity to promote intestinal pathology. Inactivation of T-bet in NKp46+ ILCs ameliorated disease. Transcriptome analysis and cell-fate mapping experiments revealed that IFNγ-producing NK1.1-ILCs correspond to ILC1 profile and develop from RORγt+ progenitors. Collectively, we identified a distinct population of NK1.1-ex-ILC3s that promotes intestinal pathology through IFNγ production in response to C. jejuni infection.


Assuntos
Infecções por Campylobacter/imunologia , Campylobacter jejuni/fisiologia , Colite/imunologia , Intestinos/imunologia , Linfócitos/imunologia , Animais , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Humanos , Imunidade Inata , Interferon gama/metabolismo , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Células Th1/imunologia
18.
Gastroenterology ; 136(2): 694-704.e4, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18952083

RESUMO

BACKGROUND & AIMS: The ability of the liver to regenerate hepatic mass is essential to withstanding liver injury. The process of liver regeneration is tightly regulated by distinct signaling cascades involving components of the innate immune system, cytokines, and growth factors. However, the role of the adaptive immune system in regulation of liver regeneration is not well-defined. The role of adaptive immune system in liver regeneration was investigated in lymphocyte-deficient mice and in conditional lymphotoxin-deficient mice. METHODS: A model of liver regeneration after 70% partial hepatectomy was used, followed by examination of liver pathology, survival, DNA synthesis, and cytokine expression. RESULTS: We found that mice deficient in T cells show a reduced capacity for liver regeneration following partial hepatectomy. Furthermore, surface lymphotoxin, provided by T cells, is critical for liver regeneration. Mice specifically deficient in T-cell lymphotoxin had increased liver damage and a reduced capacity to initiate DNA synthesis after partial hepatectomy. Transfer of splenocytes from wild-type but not lymphotoxin-deficient mice improved liver regeneration in T cell-deficient mice. We found that an agonistic antibody against the lymphotoxin beta receptor was able to facilitate liver regeneration by reducing liver injury, increasing interleukin-6 production, hepatocyte DNA synthesis, and survival of lymphocyte-deficient (Rag) mice after partial hepatectomy. CONCLUSIONS: The adaptive immune system directly regulates liver regeneration via a T cell-derived lymphotoxin axis, and pharmacological stimulation of lymphotoxin beta receptor might represent a novel therapeutic approach to improve liver regeneration.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Regeneração Hepática/fisiologia , Linfotoxina-alfa/metabolismo , Linfotoxina-beta/metabolismo , Animais , Hepatectomia , Sistema Imunitário/fisiologia , Interleucina-6/metabolismo , Fígado/citologia , Fígado/metabolismo , Fígado/cirurgia , Receptor beta de Linfotoxina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/fisiologia , Baço/citologia
19.
Front Immunol ; 11: 579615, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33488580

RESUMO

Human pathogen Campylobacter jejuni is a significant risk factor for the development of long-term intestinal dysfunction although the cellular and molecular mechanisms remain scantily defined. IL-23 is an emerging therapeutic target for the treatment of inflammatory intestinal diseases, however its role in C. jejuni-driven intestinal pathology is not fully understood. IL-10 deficient mice represent a robust model to study the pathogenesis of C. jejuni infection because C. jejuni infection of mice lacking IL-10 results in symptoms and pathology that resemble human campylobacteriosis. To determine the role of IL-23 in C. jejuni-driven intestinal inflammation, we studied the disease pathogenesis in IL-23-/- mice with inhibited IL-10Rα signaling. These mice exhibited reduced intestinal pathology independent from bacterial clearance. Further, levels of IFNγ, IL-17, IL-22, TNF, and IL-6 were reduced and associated with reduced accumulation of neutrophils, monocytes and macrophages in the colon. Flow cytometry analysis revealed reduced production of IL-17 and IFNγ by group 1 and 3 innate lymphoid cells. Thus, our data suggest that IL-23 contributes to intestinal inflammation in C. jejuni infected mice by promoting IL-17 and IFNγ production by innate lymphoid cells.


Assuntos
Infecções por Campylobacter/imunologia , Campylobacter jejuni/fisiologia , Colite/imunologia , Interleucina-23/metabolismo , Intestinos/patologia , Linfócitos/imunologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Humanos , Imunidade Inata , Interferon gama/metabolismo , Interleucina-10/genética , Interleucina-17/metabolismo , Interleucina-23/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
20.
Brain Sci ; 10(9)2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32916851

RESUMO

BACKGROUND: brain-derived neurotrophic factor (BDNF) may play a role during neurorehabilitation following ischemic stroke. This study aimed to elucidate the possible role of BDNF during early recovery from ischemic stroke assisted by motor training. METHODS: fifty patients were included after acute recovery from ischemic stroke: 21 first received classical rehabilitation followed by 'motor rehabilitation using motion sensors and augmented reality' (AR-rehabilitation), 14 only received AR-rehabilitation, and 15 were only observed. Serum BDNF levels were measured on the first day of stroke, on the 14th day, before AR-based rehabilitation (median, 45th day), and after the AR-based rehabilitation (median, 82nd day). Motor impairment was quantified clinically using the Fugl-Meyer scale (FMA); functional disability and activities of daily living (ADL) were measured using the Modified Rankin Scale (mRS). For comparison, serum BDNF was measured in 50 healthy individuals. RESULTS: BDNF levels were found to significantly increase during the phase with AR-based rehabilitation. The pattern of the sequentially measured BDNF levels was similar in the treated patients. Untreated patients had significantly lower BDNF levels at the endpoint. CONCLUSIONS: the fluctuations of BDNF levels are not consistently related to motor improvement but seem to react to active treatment. Without active rehabilitation treatment, BDNF tends to decrease.

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