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Immune mediators affect multiple biological functions of intestinal epithelial cells (IECs) and, like Paneth and Paneth-like cells, play an important role in intestinal epithelial homeostasis. IFN-γ a prototypical proinflammatory cytokine disrupts intestinal epithelial homeostasis. However, the mechanism underlying the process remains unknown. In this study, using in vivo and in vitro models we demonstrate that IFN-γ is spontaneously secreted in the small intestine. Furthermore, we observed that this cytokine stimulates mitochondrial activity, ROS production, and Paneth and Paneth-like cell secretion. Paneth and Paneth-like secretion downstream of IFN-γ, as identified here, is mTORC1 and necroptosis-dependent. Thus, our findings revealed that the pleiotropic function of IFN-γ also includes the regulation of Paneth cell function in the homeostatic gut.
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Overuse of antimicrobials has greatly contributed to the increase in the emergence of multidrug-resistant bacteria, a situation that hinders the control and treatment of infectious diseases. This is the case with urinary tract infections (UTIs), which represent a substantial percentage of worldwide public health problems, thus the need to look for alternatives for their control and treatment. Previous studies have shown the usefulness of autologous bacterial lysates as an alternative for the treatment and control of UTIs. However, a limitation is the high cost of producing individual immunogens. At the same time, an important aspect of vaccines is their immunogenic amplitude, which is the reason why they must be constituted of diverse antigenic components. In the case of UTIs, the etiology of the disease is associated with different bacteria, and even Escherichia coli, the main causal agent of the disease, is made up of several antigenic variants. In this work, we present results on the study of a bacterial lysate composed of 10 serotypes of Escherichia coli and by Klebsiella pneumoniae, Klebsiella aerogenes, Enterococcus faecalis, Proteus mirabilis, Citrobacter freundii, and Staphylococcus haemolyticus. The safety of the compound was tested on cells in culture and in an animal model, and its immunogenic capacity by analysing in vitro human and murine macrophages (cell line J774 A1). The results show that the polyvalent lysate did not cause damage to the cells in culture or alterations in the animal model used. The immunostimulatory activity assay showed that it activates the secretion of TNF-α and IL-6 in human macrophages and TNF-α in murine cells. The obtained results suggest that the polyvalent lysate evaluated can be an alternative for the treatment and control of chronic urinary tract infections, which will reduce the use of antimicrobials.
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Infecções Urinárias , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , Infecções Urinárias/imunologia , Infecções Urinárias/terapia , Animais , Humanos , Camundongos , Escherichia coli , Feminino , Extratos Celulares/farmacologia , Extratos Celulares/uso terapêutico , Lisados BacterianosRESUMO
Parasites have been associated with possible anticancer activity, including Trypanosoma cruzi, which has been linked to inhibiting the growth of solid tumors. To better understand this antitumor effect, we investigated the association of anti-T. cruzi antibodies with B cells of the acute lymphoblastic leukemia (ALL) SUPB15 cell line. The antibodies were generated in rabbits. IgGs were purified by affinity chromatography. Two procedures (flow cytometry (CF) and Western blot(WB)) were employed to recognize anti-T. cruzi antibodies on SUPB15 cells. We also used CF to determine whether the anti-T. cruzi antibodies could suppress SUPB15 cells. The anti-T. cruzi antibodies recognized 35.5% of the surface antigens of SUPB15. The complement-dependent cytotoxicity (CDC) results demonstrate the cross-suppression of anti-T. cruzi antibodies on up to 8.4% of SUPB15 cells. For the WB analysis, a band at 100 kDa with high intensity was sequenced using mass spectrometry, identifying the protein as nucleolin. This protein may play a role in the antitumor effect on T. cruzi. The anti-T. cruzi antibodies represent promising polyclonal antibodies that have the effect of tumor-suppressive cross-linking on cancer cells, which should be further investigated.
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Anticorpos Antiprotozoários , Leucemia-Linfoma Linfoblástico de Células Precursoras , Trypanosoma cruzi , Trypanosoma cruzi/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Humanos , Linhagem Celular Tumoral , Animais , Coelhos , Anticorpos Antiprotozoários/imunologia , Proteínas de Ligação a RNA/imunologia , Proteínas de Ligação a RNA/metabolismo , Nucleolina , Fosfoproteínas/imunologia , Fosfoproteínas/metabolismoRESUMO
Enteropathogenic bacterial infections are a global health issue associated with high mortality, particularly in developing countries. Efficient host protection against enteropathogenic bacterial infection is characterized by coordinated responses between immune and nonimmune cells. In response to infection in mice, innate immune cells are activated to produce interleukin (IL)-23 and IL-22, which promote antimicrobial peptide (AMP) production and bacterial clearance. IL-36 cytokines are proinflammatory IL-1 superfamily members, yet their role in enteropathogenic bacterial infection remains poorly defined. Using the enteric mouse pathogen, C.rodentium, we demonstrate that signaling via IL-36 receptor (IL-36R) orchestrates a crucial innate-adaptive immune link to control bacterial infection. IL-36R-deficient mice (Il1rl2-/- ) exhibited significant impairment in expression of IL-22 and AMPs, increased intestinal damage, and failed to contain C. rodentium compared to controls. These defects were associated with failure to induce IL-23 and IL-6, two key IL-22 inducers in the early and late phases of infection, respectively. Treatment of Il1rl2-/- mice with IL-23 during the early phase of C. rodentium infection rescued IL-22 production from group 3 innate lymphoid cells (ILCs), whereas IL-6 administration during the late phase rescued IL-22-mediated production from CD4+ T cell, and both treatments protected Il1rl2-/- mice from uncontained infection. Furthermore, IL-36R-mediated IL-22 production by CD4+ T cells was dependent upon NFκB-p65 and IL-6 expression in dendritic cells (DCs), as well as aryl hydrocarbon receptor (AhR) expression by CD4+ T cells. Collectively, these data demonstrate that the IL-36 signaling pathway integrates innate and adaptive immunity leading to host defense against enteropathogenic bacterial infection.
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Imunidade Adaptativa , Citrobacter rodentium/imunologia , Infecções por Enterobacteriaceae/imunologia , Imunidade Inata , Receptores de Interleucina-1/metabolismo , Animais , Citrobacter rodentium/patogenicidade , Modelos Animais de Doenças , Infecções por Enterobacteriaceae/microbiologia , Interleucina-1/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Camundongos , Camundongos Knockout , Receptores de Interleucina-1/genética , Transdução de Sinais/genética , Transdução de Sinais/imunologiaRESUMO
In this study, the genomes of two lytic bacteriophages, vB_EcoS-phiEc3 and vB_EcoS-phiEc4, were sequenced and characterized using bioinformatics approaches. Whole-genome analysis showed that both phages belonged to the Kagunavirus genus, Guernseyvirinae subfamily and Siphoviridae family. Moreover, their genomes had 45, 288 bp and 44,540 bp, and G + C content of 48.42% and 50.04%, respectively. The genome of vB_EcoS-phiEc3 harbored 80 protein coding sequences (CDSs), whereas vB_EcoS-phiEc4 harbored 75 CDSs. Among them, 50 CDSs in vB_EcoS-phiEc3 and 44 CDSs in vB_EcoS-phiEc4 were considered as functional genes. Their lytic activity against multidrug-resistant uropathogenic Escherichia coli (UPEC) strains, as well as the absence of antibiotic resistance genes, lysogenic and virulence genes, enable vB_EcoS-phiEc3 and vB_EcoS-phiEc4 as a safe therapy option against UPEC infections.
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Bacteriófagos , Infecções por Escherichia coli , Siphoviridae , Escherichia coli Uropatogênica , Bacteriófagos/genética , Genoma Viral , Humanos , Siphoviridae/genética , Escherichia coli Uropatogênica/genéticaRESUMO
Homogeneous extremely low-frequency electromagnetic fields (ELF-EMFs) alter biological phenomena, including the cell phenotype and proliferation rate. Heterogenous vortex magnetic fields (VMFs), a new approach of exposure to magnetic fields, induce systematic movements on charged biomolecules from target cells; however, the effect of VMFs on living systems remains uncertain. Here, we designed, constructed, and characterized an ELF-VMF-modified Rodin's coil to expose SH-SY5Y cells. Samples were analyzed by performing 2D-differential-gel electrophoresis, identified by MALDI-TOF/TOF, validated by western blotting, and characterized by confocal microscopy. A total of 106 protein spots were differentially expressed; 40 spots were downregulated and 66 were upregulated in the exposed cell proteome, compared to the control cell proteome. The identified spots are associated with cytoskeleton and cell viability proteins, and according to the protein-protein interaction network, a significant interaction among them was found. Our data revealed a decrease in cell survival associated with apoptotic cells without effects on the cell cycle, as well as evident changes in the cytoskeleton. We demonstrated that ELF-VMFs, at a specific frequency and exposure time, alter the cell proteome and structurally affect the target cells. This is the first report showing that VMF application might be a versatile system for testing different hypotheses in living systems, using appropriate exposure parameters.© 2022 Bioelectromagnetics Society.
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Neuroblastoma , Proteoma , Apoptose , Linhagem Celular , Citoesqueleto , Campos Eletromagnéticos , Humanos , Campos MagnéticosRESUMO
Mice lacking junctional adhesion molecule A (JAM-A, encoded by F11r) exhibit enhanced intestinal epithelial permeability, bacterial translocation, and elevated colonic lymphocyte numbers, yet do not develop colitis. To investigate the contribution of adaptive immune compensation in response to increased intestinal epithelial permeability, we examined the susceptibility of F11r(-/-)Rag1(-/-) mice to acute colitis. Although negligible contributions of adaptive immunity in F11r(+/+)Rag1(-/-) mice were observed, F11r(-/-)Rag1(-/-) mice exhibited increased microflora-dependent colitis. Elimination of T cell subsets and cytokine analyses revealed a protective role for TGF-ß-producing CD4(+) T cells in F11r(-/-) mice. Additionally, loss of JAM-A resulted in elevated mucosal and serum IgA that was dependent upon CD4(+) T cells and TGF-ß. Absence of IgA in F11r(+/+)Igha(-/-) mice did not affect disease, whereas F11r(-/-)Igha(-/-) mice displayed markedly increased susceptibility to acute injury-induced colitis. These data establish a role for adaptive immune-mediated protection from acute colitis under conditions of intestinal epithelial barrier compromise.
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Imunidade Adaptativa/imunologia , Colite/imunologia , Mucosa Intestinal/imunologia , Intestinos/imunologia , Imunidade Adaptativa/genética , Animais , Translocação Bacteriana/genética , Translocação Bacteriana/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/imunologia , Colite/induzido quimicamente , Colite/genética , Sulfato de Dextrana , Epitélio/imunologia , Epitélio/metabolismo , Feminino , Citometria de Fluxo , Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Imunoglobulina A/genética , Imunoglobulina A/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Permeabilidade , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismoRESUMO
The gut epithelium acts to separate host immune cells from unrestricted interactions with the microbiota and other environmental stimuli. In response to epithelial damage or dysfunction, immune cells are activated to produce interleukin (IL)-22, which is involved in repair and protection of barrier surfaces. However, the specific pathways leading to IL-22 and associated antimicrobial peptide (AMP) production in response to intestinal tissue damage remain incompletely understood. Here, we define a critical IL-36/IL-23/IL-22 cytokine network that is instrumental for AMP production and host defense. Using a murine model of intestinal damage and repair, we show that IL-36γ is a potent inducer of IL-23 both in vitro and in vivo. IL-36γ-induced IL-23 required Notch2-dependent (CD11b+CD103+) dendritic cells (DCs), but not Batf3-dependent (CD11b-CD103+) DCs or CSF1R-dependent macrophages. The intracellular signaling cascade linking IL-36 receptor (IL-36R) to IL-23 production by DCs involved MyD88 and the NF-κB subunits c-Rel and p50. Consistent with in vitro observations, IL-36R- and IL-36γ-deficient mice exhibited dramatically reduced IL-23, IL-22, and AMP levels, and consequently failed to recover from acute intestinal damage. Interestingly, impaired recovery of mice deficient in IL-36R or IL-36γ could be rescued by treatment with exogenous IL-23. This recovery was accompanied by a restoration of IL-22 and AMP expression in the colon. Collectively, these data define a cytokine network involving IL-36γ, IL-23, and IL-22 that is activated in response to intestinal barrier damage and involved in providing critical host defense.
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Imunidade Inata/imunologia , Doenças Inflamatórias Intestinais/imunologia , Interleucinas/imunologia , Cicatrização/imunologia , Animais , Doenças Inflamatórias Intestinais/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Camundongos , Camundongos TransgênicosRESUMO
Overfishing of sea cucumber Isostichopus badionotus from Yucatan has led to a major population decline. They are being captured as an alternative to traditional species despite a paucity of information about their health-promoting properties. The transcriptome of the body wall of wild and farmed I. badionotus has now been studied for the first time by an RNA-Seq approach. The functional profile of wild I. badionotus was comparable with data in the literature for other regularly captured species. In contrast, the metabolism of first generation farmed I. badionotus was impaired. This had multiple possible causes including a sub-optimal growth environment and impaired nutrient utilization. Several key metabolic pathways that are important in effective handling and accretion of nutrients and energy, or clearance of harmful cellular metabolites, were disrupted or dysregulated. For instance, collagen mRNAs were greatly reduced and deposition of collagen proteins impaired. Wild I. badionotus is, therefore, a suitable alternative to other widely used species but, at present, the potential of farmed I. badionotus is unclear. The environmental or nutritional factors responsible for their impaired function in culture remain unknown, but the present data gives useful pointers to the underlying problems associated with their aquaculture.
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Animais Domésticos/genética , Animais Selvagens/genética , Perfilação da Expressão Gênica , Pepinos-do-Mar/genética , Transcriptoma , Animais , Biologia Computacional/métodos , Perfilação da Expressão Gênica/métodos , Ontologia Genética , Reprodutibilidade dos TestesRESUMO
In the development of cervical cancer (CC), the immune response plays an essential role, from the elimination of human papillomavirus (HPV) infection to the response against the tumor. For optimal function of the immune response, various factors are required, one of the most important being an adequate nutrition. The complex interaction between nutrients and microbiota maintains the immune system in homeostasis and in case of infection, it provides the ability to fight against pathogen invasion, as occurs in HPV infection. The purpose of this article is to describe the role of diet, food, and specific nutrients in the immune response from the onset of infection to progression to precancerous lesions and CC, as well as the role of diet and nutrition during oncological treatment. The immunomodulatory role of microbiota is also discussed. A detailed analysis of the evidence leads us to recommend a nutritional pattern very similar to the Mediterranean diet or the prudent diet for an optimal immune response. Moreover, pre- and probiotics favorably modulate the microbiota and induce preventive and therapeutic effects against cancer.
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Imunidade , Estado Nutricional , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Dieta , Feminino , Microbioma Gastrointestinal , Humanos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/imunologia , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/terapiaRESUMO
Background and objectives: Type 2 diabetes (T2D) is a major problem of public health in Mexico. We investigated the influence of five polymorphisms, previously associated with obesity and cardiovascular disease in Europeans and Asians, on T2D in Mexican Mestizos. Materials and Methods: A total of 1358 subjects from 30 to 85 years old were genotyped for five loci: CXCL12 rs501120; CDNK2A/B rs1333049; HNF-1α rs2259816; FTO rs9939609; and LEP rs7799039. We used logistic regressions to test the effect of each locus on T2D in two caseâ»control groups with obesity and without obesity. Also, linear regression models on glucose and glycated hemoglobin (HbA1c) were carried out on the whole sample, adjusted by age, gender, and body mass index. Results: The CXCL12 rs501120 C allele (OR = 1.96, p = 0.02), the FTO rs9939609 A allele (OR = 2.20, p = 0.04) and the LEP rs7799039 A allele (OR = 0.6, p = 0.03) were significantly associated with T2D in obesity caseâ»control group. No significant association was found in the non-obesity caseâ»control group. The linear regression model showed that CDNK2A/B rs1333049 C allele (ß = 0.4, p = 0.03) and FTO rs9939609 A allele (ß = 0.5, p = 0.03), were significantly associated with HbA1c, but no association was found among the loci with the glucose levels. Conclusions: Polymorphisms previously linked with obesity and cardiovascular events were also associated with T2D and high levels of HbA1c. Furthermore, we must point at the fact that this is the first report where polymorphisms CXCL12 rs501120 and LEP rs7799039 are associated with T2D in subjects with obesity.
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Doenças Cardiovasculares/genética , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/genética , Obesidade/genética , Polimorfismo Genético , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Quimiocina CXCL12/genética , Diabetes Mellitus Tipo 2/etiologia , Feminino , Humanos , Leptina/genética , Modelos Lineares , Modelos Logísticos , Masculino , México/etnologia , Pessoa de Meia-Idade , Obesidade/complicações , População BrancaRESUMO
IL-1 family members are central mediators of host defense. In this article, we show that the novel IL-1 family member IL-36γ was expressed during experimental colitis and human inflammatory bowel disease. Germ-free mice failed to induce IL-36γ in response to dextran sodium sulfate (DSS)-induced damage, suggesting that gut microbiota are involved in its induction. Surprisingly, IL-36R-deficient (Il1rl2(-/-)) mice exhibited defective recovery following DSS-induced damage and impaired closure of colonic mucosal biopsy wounds, which coincided with impaired neutrophil accumulation in the wound bed. Failure of Il1rl2(-/-) mice to recover from DSS-induced damage was associated with a profound reduction in IL-22 expression, particularly by colonic neutrophils. Defective recovery of Il1rl2(-/-) mice could be rescued by an aryl hydrocarbon receptor agonist, which was sufficient to restore IL-22 expression and promote full recovery from DSS-induced damage. These findings implicate the IL-36/IL-36R axis in the resolution of intestinal mucosal wounds.
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Colite/imunologia , Interleucina-1/biossíntese , Interleucinas/biossíntese , Receptores de Interleucina/imunologia , Cicatrização/imunologia , Animais , Colite/induzido quimicamente , Colite/microbiologia , Colo/imunologia , Colo/lesões , Sulfato de Dextrana , Helicobacter hepaticus/patogenicidade , Humanos , Inflamação/imunologia , Inflamação/patologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos/imunologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Interleucina/genética , Cicatrização/genética , Interleucina 22RESUMO
The gastrointestinal tract is the largest hormone-producing organ in the body due to a specialized cell population called enteroendocrine cells (EECs). The number of EECs increases in the mucosa of inflammatory bowel disease patients; however, the mechanisms responsible for these changes remain unknown. Here, we show that the pro-inflammatory cytokines interferon γ (IFNγ) and tumor necrosis factor α (TNFα) or dextran sulfate sodium (DSS)-induced colitis increase the number of EECs producing chromogranin A (CgA) in the colonic mucosa of C57BL/6J mice. CgA-positive cells were non-proliferating cells enriched with inactive phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and autophagy markers. Moreover, inhibition of Akt and autophagy prevented the increase in CgA-positive cells after IFNγ/TNFα treatment. Similarly, we observed that CgA-positive cells in the colonic mucosa of patients with colitis expressed Akt and autophagy markers. These findings suggest that Akt signaling and autophagy control differentiation of the intestinal EEC lineage during inflammation.
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Cromogranina A/metabolismo , Colo/citologia , Citocinas/farmacologia , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Células Neuroendócrinas/efeitos dos fármacos , Células Neuroendócrinas/metabolismo , Animais , Autofagia/efeitos dos fármacos , Western Blotting , Células CACO-2 , Colite/metabolismo , Imunofluorescência , Humanos , Interferon gama/farmacologia , Interleucina-1beta/farmacologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
IL-17-expressing CD4+ T lymphocytes (Th17 cells) naturally reside in the intestine where specific cytokines and microbiota, such as segmented filamentous bacteria (SFB), promote their differentiation. Intestinal Th17 cells are thought to initially differentiate in the GALT and/or mesenteric lymph nodes upon Ag encounter and subsequently home to the lamina propria (LP) where they mediate effector functions. However, whether GALT and/or mesenteric lymph nodes are required for intestinal Th17 differentiation as well as how microbiota containing SFB regulate Ag-specific intestinal Th17 cells remain poorly defined. In this study, we observed that naive CD4+ T cells were abundant in the intestinal LP prior to weaning and that the accumulation of Th17 cells in response to microbiota containing SFB occurred in the absence of lymphotoxin-dependent lymphoid structures and the spleen. Furthermore, the differentiation of intestinal Th17 cells in the presence of microbiota containing SFB was dependent on MHC class II expression by CD11c+ cells. Lastly, the differentiation of Ag-specific Th17 cells required both the presence of cognate Ag and microbiota containing SFB. These findings suggest that microbiota containing SFB create an intestinal milieu that may induce Ag-specific Th17 differentiation against food and/or bacterial Ags directly in the intestinal LP.
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Bactérias/imunologia , Diferenciação Celular/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Intestinos , Linfonodos/imunologia , Mesentério/imunologia , Células Th17/imunologia , Animais , Antígenos de Bactérias/imunologia , Diferenciação Celular/genética , Antígenos de Histocompatibilidade Classe II/genética , Intestinos/imunologia , Intestinos/microbiologia , Camundongos , Camundongos Knockout , Células Th17/citologiaRESUMO
Cervical cancer (CC) is a significant health problem, especially in low-income countries. Functional studies on the human papillomavirus have generated essential advances in the knowledge of CC. However, many unanswered questions remain. This mini-review discusses the latest results on CC pathogenesis, HPV oncogenesis, and molecular changes identified through next-generation technologies. Interestingly, the percentage of samples with HPV genome integrations correlates with the degree of the cervical lesions, suggesting a role in the development of CC. Also, new functions have been described for the viral oncoproteins E5, E6, and E7, resulting in the acquisition and maintenance of cancer hallmarks, including proliferation, immune response evasion, apoptosis, and genomic instability. Remarkably, E5 oncoprotein affects signaling pathways involved in the expression of interferon-induced genes and EGFR-induced proliferation, while E6 and E7 oncoproteins regulate the DNA damage repair and cell cycle continuity pathways. Furthermore, next-generation technologies provide vast amounts of information, increasing our knowledge of changes in the genome, transcriptome, proteome, metabolome, and epigenome in CC. These studies have identified novel molecular traits associated with disease susceptibility, degree of progression, treatment response, and survival as potential biomarkers and therapeutic targets.
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Although several subsets of intestinal APCs have been described, there has been no systematic evaluation of their phenotypes, functions, and regional localization to date. In this article, we used 10-color flow cytometry to define the major APC subsets in the small and large intestine lamina propria. Lamina propria APCs could be subdivided into CD11c(+)CD11b(-), CD11c(+)CD11b(+), and CD11c(dull)CD11b(+) subsets. CD11c(+)CD11b(-) cells were largely CD103(+)F4/80(-) dendritic cells (DCs), whereas the CD11c(+)CD11b(+) subset comprised CD11c(+)CD11b(+)CD103(+)F4/80(-) DCs and CD11c(+)CD11b(+)CD103(-)F4/80(+) macrophage-like cells. The majority of CD11c(dull)CD11b(+) cells were CD103(-)F4/80(+) macrophages. Although macrophages were more efficient at inducing Foxp3(+) regulatory T (T(reg)) cells than DCs, at higher T cell/APC ratios, all of the DC subsets efficiently induced Foxp3(+) T(reg) cells. In contrast, only CD11c(+)CD11b(+)CD103(+) DCs efficiently induced Th17 cells. Consistent with this, the regional distribution of CD11c(+)CD11b(+)CD103(+) DCs correlated with that of Th17 cells, with duodenum > jejunum > ileum > colon. Conversely, CD11c(+)CD11b(-)CD103(+) DCs, macrophages, and Foxp3(+) T(reg) cells were most abundant in the colon and scarce in the duodenum. Importantly, however, the ability of DC and macrophage subsets to induce Foxp3(+) T(reg) cells versus Th17 cells was strikingly dependent on the source of the mouse strain. Thus, DCs from C57BL/6 mice from Charles River Laboratories (that have segmented filamentous bacteria, which induce robust levels of Th17 cells in situ) were more efficient at inducing Th17 cells and less efficient at inducing Foxp3(+) T(reg) cells than DCs from B6 mice from The Jackson Laboratory. Thus, the functional specializations of APC subsets in the intestine are dependent on the T cell/APC ratio, regional localization, and source of the mouse strain.
Assuntos
Células Apresentadoras de Antígenos/citologia , Células Dendríticas/imunologia , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/imunologia , Macrófagos/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Sequência de Aminoácidos , Animais , Células Apresentadoras de Antígenos/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Células Cultivadas , Doença Crônica , Técnicas de Cocultura , Colite/genética , Colite/imunologia , Colite/patologia , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Mucosa Intestinal/metabolismo , Contagem de Linfócitos , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Especificidade da Espécie , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Células Th17/citologia , Células Th17/metabolismoRESUMO
Staphylococcus aureus (S. aureus) is a common pathogen involved in community- and hospital-acquired infections. Its biofilm formation ability predisposes it to device-related infections. Methicillin-resistant S. aureus (MRSA) strains are associated with more serious infections and higher mortality rates and are more complex in terms of antibiotic resistance. It is still controversial whether MRSA are indeed more virulent than methicillin-susceptible S. aureus (MSSA) strains. A difference in biofilm formation by both types of bacteria has been suggested, but how only the presence of the SCCmec cassette or mecA influences this phenotype remains unclear. In this review, we have searched for literature studying the difference in biofilm formation by MRSA and MSSA. We highlighted the relevance of the icaADBC operon in the PIA-dependent biofilms generated by MSSA under osmotic stress conditions, and the role of extracellular DNA and surface proteins in the PIA-independent biofilms generated by MRSA. We described the prominent role of surface proteins with the LPXTG motif and hydrolases for the release of extracellular DNA in the MRSA biofilm formation. Finally, we explained the main regulatory systems in S. aureus involved in virulence and biofilm formation, such as the SarA and Agr systems. As most of the studies were in vitro using inert surfaces, it will be necessary in the future to focus on biofilm formation on extracellular matrix components and its relevance in the pathogenesis of infection by both types of strains using in vivo animal models.
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The vertebral column defines a vertebrate and shapes the spinal canal, a cavity that encloses and safeguards the spinal cord. Proper development and function of the mammalian central nervous system rely significantly on the activity of resident macrophages known as microglia. Microglia display heterogeneity and multifunctionality, enabling distinct gene expression and behavior within the spinal cord and brain. Numerous studies have explored cerebral microglia function, detailing purification methods extensively. However, the purification of microglia from the spinal cord in mice lacks a comprehensive description. In contrast, the utilization of a highly purified collagenase, as opposed to an unrefined extract, lacks reporting within central nervous system tissues. In this study, the vertebral column and spinal cord were excised from 8-10 week-old C57BL/6 mice. Subsequent digestion employed a highly purified collagenase, and microglia purification utilized a density gradient. Cells underwent staining for flow cytometry, assessing viability and purity through CD11b and CD45 staining. Results yielded an average viability of 80% and a mean purity of 95%. In conclusion, manipulation of mouse microglia involved digestion with a highly purified collagenase, followed by a density gradient. This approach effectively produced substantial spinal cord microglia populations.
Assuntos
Microglia , Traumatismos da Medula Espinal , Camundongos , Animais , Microglia/metabolismo , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Medula Espinal/metabolismo , Colagenases/metabolismo , MamíferosRESUMO
Immunological mechanisms of non-IgE-mediated cow's milk protein allergy (CMPA) are not well understood. Such a circumstance requires attention with the aim of discovering new biomarkers that could lead to better diagnostic assays for early treatment. Here, we sought both to investigate the mechanism that underlies non-IgE-mediated CMPA and to identify cow's milk immunoreactive proteins in a Mexican pediatric patient group (n = 34). Hence, we determined the IgE and IgG1-4 subclass antibody levels against cow's milk proteins (CMP) by ELISA. Then, we performed 2D-Immunoblots using as first antibody immunoglobulins in the patients'serum that bound specifically against CMP together with CMP enrichment by ion-exchange chromatography. Immunoreactive proteins were identified by mass spectrometry-based proteomics. The serological test confirmed absence of specific IgE in the CMPA patients but showed significant increase in antigen-specific IgG1. Additionally, we identified 11 proteins that specifically bound to IgG1. We conclude that the detection of specific IgG1 together with an immunoproteomics approach is highly relevant to the understanding of CMPA's physiopathology and as a possible aid in making a prognosis since current evidence indicates IgG1 occurrence as an early signal of potential risk toward development of IgE-mediated food allergy. SIGNIFICANCE: Allergies are one of the most studied topics in the field of public health and novel protein allergens are found each year. Discovery of new principal and regional allergens has remarkable repercussions in precise molecular diagnostics, prognostics, and more specific immunotherapies. In this context, specific IgE is widely known to mediate physiopathology; however, allergies whose mechanism does not involve this immunoglobulin are poorly understood although their incidence has increased. Therefore, accurate diagnosis and adequate treatment are delayed with significant consequences on the health of pediatric patients. The study of type and subtypes of immunoglobulins associated with the immunoreactivity of cow's milk proteins together with an immunoproteomics approach allows better comprehension of physiopathology, brings the opportunity to discover new potential cow's milk protein allergens and may help in prognosis prediction (IgG1 occurrence as an early signal of possible risk toward development of IgE-mediated food allergy).
Assuntos
Hipersensibilidade Alimentar , Hipersensibilidade a Leite , Animais , Feminino , Bovinos , Hipersensibilidade a Leite/diagnóstico , Imunoglobulina E , Hipersensibilidade Alimentar/diagnóstico , Alérgenos , Proteínas do Leite , Imunoglobulina GRESUMO
T cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy that is still fatal in many cases. T cell blasts are characterized by hyperactivation and strong proliferative and migratory capacities. The chemokine receptor CXCR4 is involved in mediating malignant T cell properties, and cortactin has been shown to control CXCR4 surface localization in T-ALL cells. We have previously shown that cortactin overexpression is correlated with organ infiltration and relapse in B-ALL. However, the role of cortactin in T cell biology and T-ALL remains elusive. Here, we analyzed the functional relevance of cortactin for T cell activation and migration and the implications for T-ALL development. We found that cortactin is upregulated in response to T cell receptor engagement and recruited to the immune synapse in normal T cells. Loss of cortactin caused reduced IL-2 production and proliferation. Cortactin-depleted T cells showed defects in immune synapse formation and migrated less due to impaired actin polymerization in response to T cell receptor and CXCR4 stimulation. Leukemic T cells expressed much higher levels of cortactin compared to normal T cells that correlated with greater migratory capacity. Xenotransplantation assays in NSG mice revealed that cortactin-depleted human leukemic T cells colonized the bone marrow significantly less and failed to infiltrate the central nervous system, suggesting that cortactin overexpression drives organ infiltration, which is a major complication of T-ALL relapse. Thus, cortactin could serve as a potential therapeutic target for T-ALL and other pathologies involving aberrant T cell responses.