Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 760
Filtrar
4.
Multimedia | Recursos Multimídia | ID: multimedia-8240
5.
Sci Rep ; 11(1): 5538, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33692390

RESUMO

Understanding antibody responses to SARS-CoV-2 is indispensable for the development of containment measures to overcome the current COVID-19 pandemic. Recent studies showed that serum from convalescent patients can display variable neutralization capacities. Still, it remains unclear whether there are specific signatures that can be used to predict neutralization. Here, we performed a detailed analysis of sera from a cohort of 101 recovered healthcare workers and we addressed their SARS-CoV-2 antibody response by ELISA against SARS-CoV-2 Spike receptor binding domain and nucleoprotein. Both ELISA methods detected sustained levels of serum IgG against both antigens. Yet, the majority of individuals from our cohort generated antibodies with low neutralization capacity and only 6% showed high neutralizing titers against both authentic SARS-CoV-2 virus and the Spike pseudotyped virus. Interestingly, higher neutralizing sera correlate with detection of -IgG, IgM and IgA antibodies against both antigens, while individuals with positive IgG alone showed poor neutralization response. These results suggest that having a broader repertoire of antibodies may contribute to more potent SARS-CoV-2 neutralization. Altogether, our work provides a cross sectional snapshot of the SARS-CoV-2 neutralizing antibody response in recovered healthcare workers and provides preliminary evidence that possessing multiple antibody isotypes can play an important role in predicting SARS-CoV-2 neutralization.


Assuntos
Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Anticorpos Antivirais/imunologia , COVID-19/terapia , Estudos de Coortes , Estudos Transversais , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Testes de Neutralização/métodos , Pandemias , SARS-CoV-2/patogenicidade , Soro/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
6.
J Surg Res ; 263: 236-244, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33713955

RESUMO

BACKGROUND: Stromal interaction molecule 1 (STIM1)-mediated store-operated Ca2+ entry (SOCE) is now recognized as the main mechanism of the majority of nonexcitable cell calcium influx. Calcium overload is a primary mechanism of endothelial cell injury during systemic inflammatory response and sepsis. Whether STIM1-mediated SOCE plays a role in calcium overload in vascular endothelial cell injury remains unclear. MATERIALS AND METHODS: To explore the role of STIM1-gated SOCE in vascular endothelial cell calcium overload and inflammation, we established a human septic serum or lipopolysaccharide (LPS)-induced human umbilical vein endothelial cell (HUVEC) experimental system and derived ribonucleic acid interference (RNAi)-mediated STIM1, ORAI1 (orai gene [HGNC: 25896 Entrez Gene: 84876] coding protein, ORAI Calcium Release-Activated Calcium Modulator 1), and transient receptor potential channel 1 (TRPC1) (core components of store-operated Ca2+[SOC]) downregulated HUVECs, as well as STIM1 overinduced HUVECs. RESULTS: Our results show that sepsis serum or LPS stimulation increased STIM1 in HUVECs and increased all cytokines except for VEGF and the inflammatory mediators tumor necrosis factor, intercellular cell adhesion molecule-1, and endothelin-1 in a time-dependent manner. RNAi-mediated knockdown of STIM1 significantly inhibited serum or LPS-induced inflammatory cytokine expression, and STIM1 overexpression in HUVECs promoted LPS-mediated induction of these cytokines. Meanwhile, similar to the blocking effect of the specific SOC inhibitors Gd3+ and La3+ on LPS-induced calcium influx, RNAi-mediated depletion of STIM1 or the SOC proteins TRPC1 and ORAI1 could significantly inhibit serum or LPS-induced extracellular calcium influx, as well as the expression of the inflammatory cytokines tumor necrosis factor, intercellular cell adhesion molecule-1, and endothelin-1. Simultaneous downregulation of the SOCE core units TRPC1 and ORAI1 inhibited LPS-induced calcium influx and cytokine expression, which could not be restored by inducing STIM1. Forced expression of nuclear factor-κB (NF-κB) in HUVECs significantly induced STIM1 expression, whereas RNAi-mediated depletion of NF-κB significantly inhibited STIM1 mRNA levels and significantly reduced the thapsigargin-mediated SOCE calcium influx, which was similar to results with the NF-κB inhibitor wogonin. CONCLUSIONS: Septic serum stimulates the expression of STIM1, cytokines, and inflammatory mediators in HUVECs. STIM1-mediated SOCE is required for Ca2+ influx induced by LPS or septic serum and contributes cytokines and inflammatory mediators in septic serum-stimulated HUVECs. In addition, STIM1-mediated SOCE on Ca2+ influx by septic serum or LPS involves NF-κB signaling.


Assuntos
Queimaduras/sangue , Cálcio/metabolismo , Endotélio Vascular/patologia , Proteínas de Neoplasias/metabolismo , Sepse/imunologia , Molécula 1 de Interação Estromal/metabolismo , Adulto , Queimaduras/imunologia , Sinalização do Cálcio/imunologia , Endotélio Vascular/imunologia , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipopolissacarídeos/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Sepse/sangue , Sepse/patologia , Soro/imunologia , Molécula 1 de Interação Estromal/genética
7.
Int J Mol Sci ; 22(3)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525644

RESUMO

Recently, generalized modules for membrane antigens (GMMA) technology has been proposed as an alternative approach to traditional glycoconjugate vaccines for O-antigen delivery. Saccharide length is a well-known parameter that can impact the immune response induced by glycoconjugates both in terms of magnitude and quality. However, the criticality of O-antigen length on the immune response induced by GMMA-based vaccines has not been fully elucidated. Here, Shigella and Salmonella GMMA-producing strains were further mutated in order to display homogeneous polysaccharide populations of different sizes on a GMMA surface. Resulting GMMA were compared in mice immunization studies. Athymic nude mice were also used to investigate the involvement of T-cells in the immune response elicited. In contrast with what has been reported for traditional glycoconjugate vaccines and independent of the pathogen and the sugar structural characteristics, O-antigen length did not result in being a critical parameter for GMMA immunogenicity. This work supports the identification of critical quality attributes to optimize GMMA vaccine design and improve vaccine efficacy and gives insights on the nature of the immune response induced by GMMA.


Assuntos
Vacinas Bacterianas/administração & dosagem , Antígenos O/genética , Salmonella typhimurium/imunologia , Shigella flexneri/imunologia , Shigella sonnei/imunologia , Animais , Anticorpos Antibacterianos/análise , Vacinas Bacterianas/imunologia , Desenho de Fármacos , Engenharia Genética , Imunização , Camundongos , Camundongos Nus , Mutação , Antígenos O/administração & dosagem , Antígenos O/imunologia , Salmonella typhimurium/genética , Soro/imunologia , Shigella flexneri/genética , Shigella sonnei/genética , Linfócitos T/imunologia
8.
Virus Res ; 292: 198228, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33188797

RESUMO

Given the dual life cycle of arboviruses in insect and animal hosts and the importance of serum factors as a first line antiviral defense, we have examined the outcome of interactions between the arbovirus La Crosse Virus (LACV) and human serum. To mimic the life cycle between species, we used LACV derived from insect (I-LACV) and human keratinocyte (HaCaT) cells. Incubation of I-LACV with normal human serum did not result in neutralization, but instead stabilized I-LACV virions and enhanced the amount of infectious virus. Enhanced infectivity was also seen with heat-inactivated serum devoid of complement activity and with serum from a range of animals including mouse, ferret, and non-human primates. Depletion of antibodies from serum resulted in loss of enhancement of infectivity and sucrose gradient sedimentation assays showed IgG co-sedimenting with I-LACV particles. In agreement with our results with I-LACV, HaCaT-derived LACV was not neutralized by complement or antibodies in normal human serum. However, in contrast to I-LACV, HaCaT-derived LACV infectivity was stable when incubated alone and treatment with serum did not enhance infectivity. Our results indicate that LACV derived from insect cells differs substantially from virus derived from human cells, with I-LACV being dependent on serum factors to enhance infectivity. These findings suggest that understanding differential composition of insect versus animal cell-derived LACV may form the foundation for potential new antiviral approaches.


Assuntos
Encefalite da Califórnia/virologia , Insetos/virologia , Queratinócitos/virologia , Vírus La Crosse/fisiologia , Soro/imunologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Encefalite da Califórnia/imunologia , Furões , Interações Hospedeiro-Patógeno , Humanos , Queratinócitos/imunologia , Vírus La Crosse/genética , Vírus La Crosse/imunologia , Camundongos , Testes de Neutralização , Primatas , Replicação Viral
10.
Indian J Dermatol Venereol Leprol ; 86(6): 632-642, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33063705

RESUMO

Background: Autologous serum therapy aims to supplement the existing pharmacotherapy in chronic urticaria by decreasing the antihistamine pill-burden and maintaining symptom-free interval. Subcutaneous autologous serum therapy further modifies the amount of serum (2 mL to 1 mL) and gauge of a needle (24G to 31G) to improve compliance and facilitate ease of application. Objectives: To assess clinical effectiveness and safety of subcutaneous autologous serum therapy versus conventional intramuscular autologous serum therapy and to compare the quality of life in the two treatment arms. Methods: Institution-based, assessor-blind, prospective, randomized, parallel-group, active-controlled trial with 32 patients in each treatment arm and analyzed on a modified intention to treat principle. After baseline autologous serum skin test, autologous serum was injected as per randomization every week for 9 consecutive weeks. Results: Among the study population, conventional intramuscular autologous serum therapy and subcutaneous autologous serum therapy had a comparable duration of disease (P = 0.164, Mann-Whitney U test), autoreactive status (P = 0.796), urticaria total severity score (P = 0.637) and urticaria activity score summed up over 7 days (P = 0.982). Both urticaria activity score summed up over 7 days and total severity score along with antihistamine pill-burden reduced significantly (P < 0.001, Friedman's analysis of variance) in both subcutaneous autologous serum therapy and conventional intramuscular autologous serum therapy from first follow-up onwards (P < 0.05, Post hoc Dunn's test). Significant improvement was noted in patient's as well as physician's global assessment of disease activity improvement scale (P < 0.001, Friedman's analysis of variance). Intergroup analysis showed that there was no significant difference in urticaria activity score summed up over 7 days either at baseline (P = 0.982, Mann-Whitney U test) or at study end (P = 0.398, Mann-Whitney U test). Similar comparable results were found in the total severity score at the end of the study (P = 0.345, Mann-Whitney U test). Dermatology life quality index showed marked improvement with both types of treatment (P < 0.0001, Wilcoxon test), and the intergroup comparison showed comparable dermatology life quality index values (P = 0.994, Mann-Whitney U test). The pain score at the injection site was more with conventional intramuscular autologous serum therapy than subcutaneous autologous serum therapy (P = 0.0115, Mann-Whitney test). Younger age and lower baseline total severity scores were associated with a better therapeutic response. Baseline urticaria activity score added up over a period of 7 days and total severity scores and the diameter of lesions showed a positive correlation with response pattern. Limitation: Basophil histamine release assay not done. Logistics could not support follow-up beyond the end of treatment. Conclusion: Subcutaneous autologous serum therapy is not inferior to conventional intramuscular autologous serum therapy with the additional advantage of less pain and operational feasibility.


Assuntos
Transfusão de Sangue Autóloga/métodos , Urticária Crônica/terapia , Soro/imunologia , Adulto , Feminino , Humanos , Injeções Intramusculares , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento , Adulto Jovem
11.
Viruses ; 12(10)2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-33008118

RESUMO

Identifying the specific epitopes targeted by antibodies elicited in response to infectious diseases is important for developing vaccines and diagnostics. However, techniques for broadly exploring the specificity of antibodies in a rapid manner are lacking, limiting our ability to quickly respond to emerging viruses. We previously reported a technology that couples deep sequencing technology with a bacteriophage MS2 virus-like particle (VLP) peptide display platform for identifying pathogen-specific antibody responses. Here, we describe refinements that expand the number of patient samples that can be processed at one time, increasing the utility of this technology for rapidly responding to emerging infectious diseases. We used dengue virus (DENV) as a model system since much is already known about the antibody response. Sera from primary DENV-infected patients (n = 28) were used to pan an MS2 bacteriophage VLP library displaying all possible 10-amino-acid peptides from the DENV polypeptide. Selected VLPs were identified by deep sequencing and further investigated by enzyme-linked immunosorbent assay. We identified previously described immunodominant regions of envelope and nonstructural protein-1, as well as a number of other epitopes. Our refinement of the deep sequence-coupled biopanning technology expands the utility of this approach for rapidly investigating the specificity of antibody responses to infectious diseases.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Bioprospecção/métodos , Epitopos/imunologia , Soro/imunologia , Antígenos Virais/química , Dengue/imunologia , Vírus da Dengue/genética , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Humanos , Levivirus/genética , Levivirus/imunologia , Modelos Moleculares , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas Virais/química
13.
Sci Rep ; 10(1): 15436, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963315

RESUMO

Humoral immunity to pathogens and other environmental challenges is paramount to maintain normal health, and individuals lacking or unable to make antibodies are at risk. Recent studies indicate that many human protective antibodies are against carbohydrate antigens; however, little is known about repertoires and individual variation of anti-carbohydrate antibodies in healthy individuals. Here we analyzed anti-carbohydrate antibody repertoires (ACARs) of 105 healthy individual adult donors, aged 20-60+ from different ethnic backgrounds to explore variations in antibodies, as defined by binding to glycan microarrays and by affinity purification. Using microarrays that contained > 1,000 glycans, including antigens from animal cells and microbes, we profiled the IgG and IgM ACARs from all donors. Each donor expressed many ACAs, but had a relatively unique ACAR, which included unanticipated antibodies to carbohydrate antigens not well studied, such as chitin oligosaccharides, Forssman-related antigens, globo-type antigens, and bacterial glycans. We also saw some expected antibodies to ABO(H) blood group and α-Gal-type antigens, although these also varied among individuals. Analysis suggests differences in ACARs are associated with ethnicity and age. Thus, each individual ACAR is relatively unique, suggesting that individualized information could be useful in precision medicine for predicting and monitoring immune health and resistance to disease.


Assuntos
Anticorpos/sangue , Antígenos/imunologia , Carboidratos/imunologia , Soro/imunologia , Sistema ABO de Grupos Sanguíneos/imunologia , Adulto , Animais , Feminino , Humanos , Imunidade Humoral/imunologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Polissacarídeos/imunologia , Adulto Jovem
14.
J Immunol Res ; 2020: 6292631, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32766318

RESUMO

A distinctive new indirect immunofluorescence pattern in liver tissue has been associated with anti-HMGCR autoantibodies. It is known as HALIP (HMGCR Associated Liver Immunofluorescence Pattern). In this study, we furthered the original studies to demonstrate the association of anti-HMGCR antibodies with the HALIP. Human anti-HMGCR antibodies from patients' sera were purified and incubated with rat triple tissue (kidney/stomach/liver). A characteristic HALIP was observed. Additionally, a colocalization assay of human anti-HMGCR antibodies with rabbit polyclonal anti-HMGCR antibodies showed colocalization of both immunofluorescence patterns. This study confirms that the HALIP is due to human anti-HMGCR antibodies.


Assuntos
Autoanticorpos/imunologia , Hidroximetilglutaril-CoA Redutases/imunologia , Animais , Imunofluorescência/métodos , Técnica Indireta de Fluorescência para Anticorpo/métodos , Humanos , Fígado/imunologia , Ratos , Soro/imunologia
15.
Fish Shellfish Immunol ; 106: 464-472, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32777461

RESUMO

The present study aims to shed light on the effects of yeast cell wall (ImmunoWall®) supplementation on biochemical indices, oxidative status, serum and mucus immune responses as well as disease resistance of juvenile Persian sturgeon (Acipenser persicus). For this purpose, one hundred fifty three juvenile Persian sturgeons (47.78 ± 0.39 g) were distributed into nine tanks (500 L) and fed with basal diets containing two levels of yeast cell wall (YCW) 0.5% (T1) and 1% (T2) and a diet without YCW as control (0%). As shown by the results obtained at the end of 56-day feeding trial, YCW had no significant effect on glucose, cortisol, SGOT, lysozyme and IgM in serum (P > 0.05) albeit an enhancement of cholesterol, LDH, ALP and SOD and ACH50 was observed in fish fed YCW supplemented diets. However, plasma triglyceride levels were lower in fish fed YCW compared with the control group. Also, total protein content, lysozyme and protease activities in skin mucus were unaffected by the supplemented diets (P > 0.05) and only total immunoglobulin and ALP enzyme activity were significantly increased in T1 and T2 groups (P > 0.05). The cumulative mortality of the fish fed supplemented diets at the end of disease challenge was 100% where cumulative mortality of those fed the control diet was 75% (P < 0.05). The present study shows that increasing immune parameters in serum and mucus of juvenile Persian sturgeon by YCW dietary supplementation did not improve resistance against Aeromonas hydrophila. According to the obtained results, the YCW supplementation at 0.5 and 1% in the juvenile Persian sturgeon diet is not recommended.


Assuntos
Resistência à Doença , Doenças dos Peixes/imunologia , Peixes/imunologia , Imunidade nas Mucosas , Estresse Oxidativo , Fermento Seco/metabolismo , Aeromonas hydrophila/fisiologia , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Distribuição Aleatória , Soro/imunologia , Pele/imunologia , Fermento Seco/administração & dosagem
16.
Nature ; 586(7830): 572-577, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32726802

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a respiratory disease called coronavirus disease 2019 (COVID-19), the spread of which has led to a pandemic. An effective preventive vaccine against this virus is urgently needed. As an essential step during infection, SARS-CoV-2 uses the receptor-binding domain (RBD) of the spike protein to engage with the receptor angiotensin-converting enzyme 2 (ACE2) on host cells1,2. Here we show that a recombinant vaccine that comprises residues 319-545 of the RBD of the spike protein induces a potent functional antibody response in immunized mice, rabbits and non-human primates (Macaca mulatta) as early as 7 or 14 days after the injection of a single vaccine dose. The sera from the immunized animals blocked the binding of the RBD to ACE2, which is expressed on the cell surface, and neutralized infection with a SARS-CoV-2 pseudovirus and live SARS-CoV-2 in vitro. Notably, vaccination also provided protection in non-human primates to an in vivo challenge with SARS-CoV-2. We found increased levels of RBD-specific antibodies in the sera of patients with COVID-19. We show that several immune pathways and CD4 T lymphocytes are involved in the induction of the vaccine antibody response. Our findings highlight the importance of the RBD domain in the design of SARS-CoV-2 vaccines and provide a rationale for the development of a protective vaccine through the induction of antibodies against the RBD domain.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , COVID-19 , Vacinas contra COVID-19 , Humanos , Macaca mulatta/imunologia , Macaca mulatta/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Animais , Modelos Moleculares , Domínios Proteicos , SARS-CoV-2 , Soro/imunologia , Baço/citologia , Baço/imunologia , Linfócitos T/imunologia , Vacinação
17.
Int Immunopharmacol ; 86: 106732, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32622200

RESUMO

BACKGROUND: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is attracting considerable attention due to disease acceleration and substantial mortality. Macrophages are known to regulate the fibrotic process in idiopathic pulmonary fibrosis. OBJECTIVE: We investigated if two new macrophage-specific serum biomarkers, soluble mannose receptor (MR, sCD206) and soluble CD163 (sCD163), increased in serum obtained from patients with AE-IPF compared to stable IPF (S-IPF). METHODS: A total of 36 IPF patients with AE status, 54 IPF patients with stable status, and 27 normal controls were enrolled in this study. The levels of serum sCD206 and sCD163 were compared among the three groups and analysed with the clinical features and mortality of IPF. RESULTS: The serum concentrations of both markers were higher in patients with AE-IPF than in those with S-IPF (580.0 ng/ml vs 335 ng/ml for sCD206 and 69.2 ng/ml vs 37.9 ng/ml for sCD163). The level of sCD206 was related to an increased risk of mortality (HR = 1.002, p < 0.001). The best separation between decedents and survivors was obtained by sCD206 (area under the receiver operating characteristic curve [AUC] 0.712 and 95% confidence interval 0.595-0.830). CONCLUSION: Our data demonstrated that the macrophage-related markers sCD206 and sCD163 were significantly higher in patients with IPF, especially sCD206 in AE-IPF patients. The high level of serum sCD206 was associated with mortality in idiopathic pulmonary fibrosis.


Assuntos
Biomarcadores/metabolismo , Fibrose Pulmonar Idiopática/imunologia , Lectinas Tipo C/metabolismo , Macrófagos/imunologia , Lectinas de Ligação a Manose/metabolismo , Receptores de Superfície Celular/metabolismo , Soro/imunologia , Idoso , Antígenos CD/sangue , Antígenos de Diferenciação Mielomonocítica/sangue , Feminino , Humanos , Fibrose Pulmonar Idiopática/mortalidade , Masculino , Pessoa de Meia-Idade , Receptores de Superfície Celular/sangue , Análise de Sobrevida
18.
Infect Immun ; 88(9)2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32571987

RESUMO

Even though both cellular and humoral immunities contribute to host defense, the role played by humoral immunity against the airborne opportunistic fungal pathogen Aspergillus fumigatus has been underexplored. In this study, we aimed at deciphering the role of the complement system, the major humoral immune component, against A. fumigatus Mass spectrometry analysis of the proteins extracted from A. fumigatus conidial (asexual spores and infective propagules) surfaces opsonized with human serum indicated that C3 is the major complement protein involved. Flow cytometry and immunolabeling assays further confirmed C3b (activated C3) deposition on the conidial surfaces. Assays using cell wall components of conidia indicated that the hydrophobin RodAp, ß-(1,3)-glucan (BG) and galactomannan (GM) could efficiently activate C3. Using complement component-depleted sera, we showed that while RodAp activates C3 by the alternative pathway, BG and GM partially follow the classical and lectin pathways, respectively. Opsonization facilitated conidial aggregation and phagocytosis, and complement receptor (CR3 and CR4) blockage on phagocytes significantly inhibited phagocytosis, indicating that the complement system exerts a protective role against conidia by opsonizing them and facilitating their phagocytosis mainly through complement receptors. Conidial opsonization with human bronchoalveolar lavage fluid (BALF) confirmed C3 to be the major complement protein interacting with conidia. Nevertheless, complement C2 and mannose-binding lectin (MBL), the classical and lectin pathway components, respectively, were not identified, indicating that BALF activates the alternative pathway on the conidial surface. Moreover, the cytokine profiles were different upon stimulation of phagocytes with serum- and BALF-opsonized conidia, highlighting the importance of studying interaction of conidia with complement proteins in their biological niche.


Assuntos
Aspergillus fumigatus/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Complemento C3/imunologia , Polissacarídeos Fúngicos/farmacologia , Macrófagos/efeitos dos fármacos , Soro/imunologia , Esporos Fúngicos/imunologia , Aspergilose/genética , Aspergilose/imunologia , Aspergilose/microbiologia , Aspergillus fumigatus/química , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/microbiologia , Parede Celular/química , Parede Celular/imunologia , Ativação do Complemento/efeitos dos fármacos , Complemento C3/genética , Citocinas/biossíntese , Citocinas/imunologia , Polissacarídeos Fúngicos/imunologia , Polissacarídeos Fúngicos/isolamento & purificação , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Imunidade Celular , Imunidade Humoral , Integrina alfaXbeta2/genética , Integrina alfaXbeta2/imunologia , Antígeno de Macrófago 1/genética , Antígeno de Macrófago 1/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Mananas/imunologia , Mananas/isolamento & purificação , Mananas/farmacologia , Proteínas Opsonizantes/farmacologia , Fagocitose/efeitos dos fármacos , Cultura Primária de Células , Ligação Proteica , Espécies Reativas de Oxigênio , Soro/química , Soro/microbiologia , Esporos Fúngicos/química , beta-Glucanas/imunologia , beta-Glucanas/isolamento & purificação , beta-Glucanas/farmacologia
19.
Sci Rep ; 10(1): 10073, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32572045

RESUMO

Cats are a critical pre-clinical model for studying adeno-associated virus (AAV) vector-mediated gene therapies. A recent study has described the high prevalence of anti-AAV neutralizing antibodies among domestic cats in Switzerland. However, our knowledge of pre-existing humoral immunity against various AAV serotypes in cats is still limited. Here, we show that, although antibodies binding known AAV serotypes (AAV1 to AAV11) are prevalent in cats living in the Northeastern United States, these antibodies do not necessarily neutralize AAV infectivity. We analyzed sera from 35 client-owned, 20 feral, and 30 specific pathogen-free (SPF) cats for pre-existing AAV-binding antibodies against the 11 serotypes. Antibody prevalence was 7 to 90% with an overall median of 50%. The AAV-binding antibodies showed broad reactivities with other serotypes. Of 44 selected antibodies binding AAV2, AAV6 or AAV9, none exhibited appreciable neutralizing activities. Instead, AAV6 or AAV9-binding antibodies showed a transduction-enhancing effect. AAV6-binding antibodies were highly prevalent in SPF cats (83%), but this was primarily due to cross-reactivity with preventive vaccine-induced anti-feline panleukopenia virus antibodies. These results indicate that prevalent pre-existing immunity in cats is not necessarily inhibitory to AAV and highlight a substantial difference in the nature of AAV-binding antibodies in cats living in geographically different regions.


Assuntos
Anticorpos Antivirais/metabolismo , Dependovirus/imunologia , Soro/imunologia , Animais , Anticorpos Neutralizantes/metabolismo , Gatos , Dependovirus/classificação , Imunidade Humoral , New England , Sorogrupo , Suíça , Transdução Genética
20.
J Clin Lab Anal ; 34(9): e23411, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32594577

RESUMO

BACKGROUND: The detection of serum antibodies to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is emerging as a new tool for the coronavirus disease 2019 (COVID-19) diagnosis. Since many coronaviruses are sensitive to heat, heating inactivation of samples at 56°C prior to testing is considered a possible method to reduce the risk of transmission, but the effect of heating on the measurement of SARS-CoV-2 antibodies is still unclear. METHODS: By comparing the levels of SARS-CoV-2 antibodies before and after heat inactivation of serum at 56°C for 30 minutes using a quantitative fluorescence immunochromatographic assay RESULTS: We showed that heat inactivation significantly interferes with the levels of antibodies to SARS-CoV-2. The IgM levels of all the 34 serum samples (100%) from COVID-19 patients decreased by an average level of 53.56%. The IgG levels were decreased in 22 of 34 samples (64.71%) by an average level of 49.54%. Similar changes can also be observed in the non-COVID-19 disease group (n = 9). Of note, 44.12% of the detected IgM levels were dropped below the cutoff value after heating, suggesting heat inactivation can lead to false-negative results of these samples. CONCLUSION: Our results indicate that heat inactivation of serum at 56°C for 30 minutes interferes with the immunoanalysis of antibodies to SARS-CoV-2. Heat inactivation prior to immunoanalysis is not recommended, and the possibility of false-negative results should be considered if the sample was pre-inactivated by heating.


Assuntos
Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/sangue , Infecções por Coronavirus/imunologia , Temperatura Alta , Imunoensaio/métodos , Pneumonia Viral/sangue , Pneumonia Viral/imunologia , Soro/imunologia , COVID-19 , Infecções por Coronavirus/virologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Pandemias , Pneumonia Viral/virologia , SARS-CoV-2
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...