RESUMO
The coronavirus disease 2019 (COVID-19) is related to enhanced production of NETs, and autoimmune/autoinflammatory phenomena. We evaluated the proportion of low-density granulocytes (LDG) by flow cytometry, and their capacity to produce NETs was compared with that of conventional neutrophils. NETs and their protein cargo were quantified by confocal microscopy and ELISA. Antinuclear antibodies (ANA), anti-neutrophil cytoplasmic antibodies (ANCA) and the degradation capacity of NETs were addressed in serum. MILLIPLEX assay was used to assess the cytokine levels in macrophages' supernatant and serum. We found a higher proportion of LDG in severe and critical COVID-19 which correlated with severity and inflammatory markers. Severe/critical COVID-19 patients had higher plasmatic NE, LL-37 and HMGB1-DNA complexes, whilst ISG-15-DNA complexes were lower in severe patients. Sera from severe/critical COVID-19 patients had lower degradation capacity of NETs, which was reverted after adding hrDNase. Anti-NET antibodies were found in COVID-19, which correlated with ANA and ANCA positivity. NET stimuli enhanced the secretion of cytokines in macrophages. This study unveils the role of COVID-19 NETs as inducers of pro-inflammatory and autoimmune responses. The deficient degradation capacity of NETs may contribute to the accumulation of these structures and anti-NET antibodies are related to the presence of autoantibodies.
Assuntos
Autoimunidade , COVID-19/sangue , COVID-19/imunologia , Armadilhas Extracelulares/imunologia , Imunidade Humoral , Inflamação , Neutrófilos/imunologia , Anticorpos Antinucleares , Peptídeos Catiônicos Antimicrobianos/sangue , Autoanticorpos/metabolismo , Estudos Transversais , Citocinas/metabolismo , Citocinas/farmacologia , Citometria de Fluxo , Granulócitos/metabolismo , Proteína HMGB1/sangue , Voluntários Saudáveis , Humanos , Microscopia Confocal , Monócitos/citologia , Neutrófilos/citologia , SARS-CoV-2 , Ubiquitinas/farmacologia , CatelicidinasRESUMO
Fcγ receptors (FcγR), cell-surface glycoproteins that bind antigen-IgG complexes, control both humoral and cellular immune responses. The FCGR locus on chromosome 1q23.3 comprises five homologous genes encoding low-affinity FcγRII and FcγRIII, and displays functionally relevant polymorphism that impacts on human health. Recurrent events of non-allelic homologous recombination across the FCGR locus result in copy-number variation of ~82.5 kbp-long fragments known as copy-number regions (CNR). Here, we characterize a recently described deletion that we name CNR5, which results in loss of FCGR3A, FCGR3B, and FCGR2C, and generation of a recombinant FCGR3B/A gene. We show that the CNR5 recombination spot lies at the beginning of the third FCGR3 intron. Although the FCGR3B/A-encoded hybrid protein CD16B/A reaches the plasma membrane in transfected cells, its possible natural expression, predictably restricted to neutrophils, could not be demonstrated in resting or interferon γ-stimulated cells. As the CNR5-deletion was originally described in an Ecuadorian family from Llano Grande (an indigenous community in North-Eastern Quito), we characterized the FCGR genetic variation in two populations from the highlands of Ecuador. Our results reveal that CNR5-deletion is relatively frequent in Llano Grande (5 carriers out of 36 donors). Furthermore, we found a high frequency of two strong-phagocytosis variants: the FCGR3B-NA1 haplotype and the CNR1 duplication, which translates into an increased FCGR3B and FCGR2C copy-number. CNR1 duplication was particularly increased in Llano Grande, 77.8% of the studied sample carrying at least one such duplication. In contrast, an extended haplotype CD16A-176V - CD32C-ORF+2B.2 - CD32B-2B.4 including strong activating and inhibitory FcγR variants was absent in Llano Grande and found at a low frequency (8.6%) in Ecuador highlands. This particular distribution of FCGR polymorphism, possibly a result of selective pressures, further confirms the importance of a comprehensive, joint analysis of all genetic variations in the locus and warrants additional studies on their putative clinical impact. In conclusion, our study confirms important ethnic variation at the FCGR locus; it shows a distinctive FCGR polymorphism distribution in Ecuador highlands; provides a molecular characterization of a novel CNR5-deletion associated with CD16A and CD16B deficiency; and confirms its presence in that population.
Assuntos
Variações do Número de Cópias de DNA , Genética Populacional , Polimorfismo de Nucleotídeo Único , Receptores de IgG/genética , Alelos , Linhagem Celular , Equador , Proteínas Ligadas por GPI/genética , Expressão Gênica , Loci Gênicos , Variação Genética , Genótipo , Granulócitos/metabolismo , HumanosRESUMO
Impaired wound healing complicates a wide range of diseases and represents a major cost to healthcare systems. Here we describe the use of discarded wound dressings as a novel, cost effective, accessible, and non-invasive method of isolating viable human cells present at the site of skin wounds. By analyzing 133 discarded wound dressings from 51 patients with the inherited skin-blistering disease epidermolysis bullosa (EB), we show that large numbers of cells, often in excess of 100 million per day, continually infiltrate wound dressings. We show, that the method is able to differentiate chronic from acute wounds, identifying significant increases in granulocytes in chronic wounds, and we show that patients with the junctional form of EB have significantly more cells infiltrating their wounds compared with patients with recessive dystrophic EB. Finally, we identify subsets of granulocytes and T lymphocytes present in all wounds paving the way for single cell profiling of innate and adaptive immune cells with relevance to wound pathologies. In summary, our study delineates findings in EB that have potential relevance for all chronic wounds, and presents a method of cellular isolation that has wide reaching clinical application.
Assuntos
Bandagens , Separação Celular , Epidermólise Bolhosa , Granulócitos , Linfócitos T , Cicatrização , Doença Aguda , Adulto , Doença Crônica , Epidermólise Bolhosa/metabolismo , Epidermólise Bolhosa/patologia , Epidermólise Bolhosa/terapia , Granulócitos/metabolismo , Granulócitos/patologia , Humanos , Masculino , Linfócitos T/metabolismo , Linfócitos T/patologiaRESUMO
This in vitro study aimed to find the best method of granulocyte isolation for subsequentlabeling with multimodal nanoparticles (magnetic and fluorescent properties) to enable detectionby optical and magnetic resonance imaging (MRI) techniques. The granulocytes were obtained fromvenous blood samples from 12 healthy volunteers. To achieve high purity and yield, four differentmethods of granulocyte isolation were evaluated. The isolated granulocytes were labeled withmultimodal superparamagnetic iron oxide nanoparticles (M-SPIONs) coated with dextran, and theiron load was evaluated qualitatively and quantitatively by MRI, near-infrared fluorescence (NIRF)and inductively coupled plasma mass spectrometry (ICP-MS). The best method of granulocyteisolation was Percoll with Ficoll, which showed 95.92% purity and 94% viability. After labeling withM-SPIONs, the granulocytes showed 98.0% purity with a yield of 3.5 × 106 cells/mL and more than98.6% viability. The iron-loading value in the labeled granulocytes, as obtained by MRI, was 6.40 ±0.18 pg/cell. Similar values were found with the ICP-MS and NIRF imaging techniques. Therefore,our study shows that it is possible to isolate granulocytes with high purity and yield and labelingwith M-SPIONs provides a high internalized iron load and low toxicity to cells. Therefore, these MSPION-labeled granulocytes could be a promising candidate for future use ininflammation/infection detection by optical and MRI techniques.
Assuntos
Separação Celular/métodos , Compostos Férricos/química , Granulócitos , Nanopartículas de Magnetita/química , Coloração e Rotulagem , Análise de Variância , Sobrevivência Celular , Granulócitos/metabolismo , Humanos , Imunofenotipagem , Espectroscopia de Ressonância Magnética , Imagem Molecular/métodosRESUMO
PURPOSE: Cutaneous T cell lymphomas (CTCL) are rare and histologically diverse lymphoproliferative neoplasms, with mycosis fungoides (MF) representing the most common disease subset. Given the emerging role of myeloid-derived suppressor cells (MDSC) as a clinically applicable biomarker in solid tumors, we sought to investigate the presence of tumor-infiltrating and circulating MDSC in early- and advanced-stage MF patients and evaluate their prognostic significance in patient overall survival. METHODS: Tumor-infiltrating MDSC were assessed immunohistochemically with Arginase-1 in 31 MF and 14 non-MF skin punch biopsies. Circulating MDSC were assessed with flow cytometry in freshly isolated PBMC from 29 MF patients. Granulocytic MDSC (G-MDSC) were defined as CD11b+CD14-CD15+ and monocytic MDSC (M-MDSC) were defined as CD11b+CD14+HLA-DRlow/-. RESULTS: MDSC infiltration occurred in approximately one-third (35.5%) of CTCL lesions, with a predilection for non-MF lesions (p < 0.05). The predominant morphology of MDSC was granulocytic. Although in MF lesions the presence of MDSC infiltrates did not correlate with clinical stage, it conferred significantly worse overall survival outcomes (p < 0.05). Circulating G-MDSC were significantly higher in MF patients compared to healthy donor controls (p < 0.0001), while M-MDSC did not show any statistically significant difference. G-MDSC were significantly higher in patients with active disease compared to patients who were in partial remission (p < 0.01). As with tumor-infiltrating MDSC, clinical stage did not correlate with circulating G-MDSC levels, while prospective overall survival analysis showed that patients with high levels of circulating G-MDSC have significantly inferior outcomes (p < 0.01). CONCLUSIONS: This study shows that G-MDSC could represent a novel and easily assessable biomarker in MF, which mirrors disease activity and can predict patient subgroups with aggressive clinical features.
Assuntos
Micose Fungoide/patologia , Células Supressoras Mieloides/patologia , Neoplasias Cutâneas/patologia , Antígeno CD11b , Contagem de Células , Feminino , Citometria de Fluxo , Granulócitos/metabolismo , Granulócitos/patologia , Antígenos HLA-DR , Humanos , Imuno-Histoquímica , Antígenos CD15 , Receptores de Lipopolissacarídeos , Masculino , Monócitos/metabolismo , Monócitos/patologia , Células Supressoras Mieloides/metabolismo , Estadiamento de Neoplasias , Prognóstico , Taxa de SobrevidaRESUMO
Vitamin A and its derivatives (retinoids) act as potent regulators in many aspects of mammalian reproduction, development, repair, and maintenance of differentiated tissue functioning. Unlike other vitamins, Vitamin A and retinoids, which have hormonal actions, present significant toxicity, which plays roles in clinically relevant situations, such as hypervitaminosis A and retinoic acid ("differentiation") syndrome. Although clinical presentation is conspicuous in states of insufficient or excessive Vitamin A and retinoid concentration, equally relevant effects on host resistance to specific infectious agents, and in the general maintenance of immune homeostasis, may go unnoticed, because their expression requires either pathogen exposure or the presence of inflammatory co-morbidities. There is a vast literature on the roles played by retinoids in the maintenance of a tolerogenic, noninflammatory environment in the gut mucosa, which is considered by many investigators representative of a general role played by retinoids as anti-inflammatory hormones elsewhere. However, in the gut mucosa itself, as well as in the bone marrow and inflammatory sites, context determines whether one observes an anti-inflammatory or proinflammatory action of retinoids. Both interactions between specialized cell populations, and interactions between retinoids and other classes of mediators/regulators, such as cytokines and glucocorticoid hormones, must be considered as important factors contributing to this overall context. We review evidence from recent studies on mucosal immunity, granulocyte biology and respiratory allergy models, highlighting the relevance of these variables as well as their possible contributions to the observed outcomes.
Assuntos
Doenças Transmissíveis/tratamento farmacológico , Retinoides/efeitos adversos , Vitamina A/efeitos adversos , Animais , Doenças Transmissíveis/imunologia , Células Dendríticas/metabolismo , Granulócitos/metabolismo , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Retinoides/uso terapêutico , Linfócitos T Reguladores/metabolismo , Vitamina A/uso terapêuticoRESUMO
In sepsis, greater understanding of the inflammatory mechanism involved would provide insights into the condition and into its extension to the muscular apparatus in critically ill patients. Therefore, this study evaluates the inflammatory profile of pneumosepsis induced by Klebsiella pneumoniae (K.p.) in lungs and skeletal muscles during the first 72â¯h. Male BALB/c mice were divided into 4 groups, submitted to intratracheal inoculation of K.p. at a concentration of 2â¯×â¯108 (PS) or PBS, and assessed after 24 (PS24), 48 (PS48) and 72 (PS72) hours. The Maximum Physical Capacity Test (MPCT) was performed before and after induction. Pulmonary inflammation was assessed by total cell number, nitric oxide levels (NOx), IL-1ß and TNF-α levels in bronchoalveolar lavage fluid (BALF); inflammation and muscle trophism were evaluated by the levels of TNF-α, IL-6, TGF-ß and BDNF by ELISA and NF-κB by western blotting in muscle tissue. Cells and colony forming units (CFU) were also analyzed in blood samples. The PS groups showed an increase in total cells in the BALF (pâ¯<â¯0.05), as well in the number of granulocytes in the blood (pâ¯<â¯0.05) and a decrease in performance in the MPCT (pâ¯<â¯0.05). NOx levels showed significant increase in PS72, when compared to Control group (pâ¯=â¯0.03). The PS24 showed a significant increase lung in TNF-α levels (pâ¯<â¯0.001) and in CFU (pâ¯=â¯0.013). We observed an increase in muscular IL-6 and nuclear NF-κB levels in PS24 group, when compared to PS48 and Control groups (pâ¯<â¯0.05). Nevertheless, mild signs of injury in the skeletal muscle tissue does not support the idea of an early muscular injury in this experimental model, suggesting that the low performance of the animals during the MPCT may be related to lung inflammation.
Assuntos
Biomarcadores/metabolismo , Inflamação/patologia , Pulmão/patologia , Músculos/patologia , Sepse/patologia , Animais , Contagem de Células , Citocinas/metabolismo , Granulócitos/metabolismo , Klebsiella pneumoniae/fisiologia , Pulmão/microbiologia , Masculino , Camundongos Endogâmicos BALB C , Músculos/microbiologia , Sepse/microbiologia , Análise de Sobrevida , Fatores de TempoAssuntos
Síndrome de Budd-Chiari/genética , Células Endoteliais/metabolismo , Granulócitos/metabolismo , Janus Quinase 2/genética , Mutação , Alelos , Substituição de Aminoácidos , Síndrome de Budd-Chiari/complicações , Síndrome de Budd-Chiari/diagnóstico , Frequência do Gene , Genótipo , Humanos , Transtornos Mieloproliferativos/complicações , Transtornos Mieloproliferativos/genética , Sequenciamento do ExomaRESUMO
Experimental findings support the evidence of a persistent leucopenia triggered by brain death (BD). This study aimed to investigate leucocyte behaviour in bone marrow and blood after BD in rats. BD was induced using intracranial balloon catheter inflation. Sham-operated (SH) rats were trepanned only. Thereafter bone marrow cells were harvested every six hours from the femoral cavity and used for total and differential counts. They were analysed further by flow cytometry to characterize lymphocyte subsets, granulocyte adhesion molecules expression and apoptosis/necrosis [annexin V/propidium iodide (PI) protocol]. BD rats exhibited a reduction in bone marrow cells due to a reduction in lymphocytes (40%) and segmented cells (45%). Bone marrow lymphocyte subsets were similar in BD and SH rats (CD3, P = 0.1; CD4, P = 0.4; CD3/CD4, P = 0.4; CD5, P = 0.4, CD3/CD5, P = 0.2; CD8, P = 0.8). Expression of L-selectin and beta2 -integrins on granulocytes did not differ (CD11a, P = 0.9; CD11b/c, P = 0.7; CD62L, P = 0.1). There were no differences in the percentage of apoptosis and necrosis (Annexin V, P = 0.73; PI, P = 0.21; Annexin V/PI, P = 0.29). In conclusion, data presented suggest that the downregulation of the bone marrow is triggered by brain death itself, and it is not related to changes in lymphocyte subsets, granulocyte adhesion molecules expression or apoptosis and necrosis.
Assuntos
Células da Medula Óssea/patologia , Morte Encefálica/patologia , Animais , Apoptose , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Morte Encefálica/imunologia , Morte Encefálica/metabolismo , Moléculas de Adesão Celular/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Granulócitos/metabolismo , Hemodinâmica/fisiologia , Contagem de Leucócitos , Leucopenia/etiologia , Subpopulações de Linfócitos/imunologia , Masculino , Necrose , Ratos WistarRESUMO
BACKGROUND: Galectin-3 is known to be a lectin that plays an important role in inflammatory processes, acting as pro-inflammatory mediator in activation and migration of neutrophils and macrophages, as well as in the phagocytic function of these cells. The injection of mineral oils into the peritoneal cavity of mice, such as 2, 6, 10, 14-tetramethylpentadecane (pristane), induce a chronic granulomatous inflammatory reaction which is rich in macrophages, B cells and peritoneal plasma cells known as oil granuloma. In addition, this inflammatory microenvironment provided by oil granulomas is also an important site of plasmacytoma induction, which are dependent on cytokine production and cellular mobilization. Here, we have analyzed the role of galectin-3 in inflammatory cells mobilization and organization after pristane injection characterizing granulomatous reaction through the formation of oil granulomas. RESULTS: In galectin-3 deficient mice (gal-3(-/-)), the mobilization of inflammatory cells, between peritoneal cavity and bone marrow, was responsible for the formation of disorganized oil granulomas, which presented scattered cells, large necrotic areas and low amounts of extracellular matrix. The production of inflammatory cytokines partially explained the distribution of cells through peritoneal cavity, since high levels of IL-6 in gal-3(-/-) mice led to drastically reduction of B1 cells. The previous pro-inflammatory status of these animals also explains the excess of cell death and disruption of oil granulomas architecture. CONCLUSIONS: Our data indicate, for the first time, that the disruption in the inflammatory cells migration in the absence of galectin-3 is a crucial event in the formation and organization of oil granulomas.