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1.
Cells ; 10(5)2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065953

RESUMO

Macrophages play a key role in induction of inflammatory responses. These inflammatory responses are mostly considered to be instigated by activation of pattern recognition receptors (PRRs) or cytokine receptors. However, recently it has become clear that also antibodies and pentraxins, which can both activate Fc receptors (FcRs), induce very powerful inflammatory responses by macrophages that can even be an order of magnitude greater than PRRs. While the physiological function of this antibody-dependent inflammation (ADI) is to counteract infections, undesired activation or over-activation of this mechanism will lead to pathology, as observed in a variety of disorders, including viral infections such as COVID-19, chronic inflammatory disorders such as Crohn's disease, and autoimmune diseases such as rheumatoid arthritis. In this review we discuss how physiological ADI provides host defense by inducing pathogen-specific immunity, and how erroneous activation of this mechanism leads to pathology. Moreover, we will provide an overview of the currently known signaling and metabolic pathways that underlie ADI, and how these can be targeted to counteract pathological inflammation.


Assuntos
Anticorpos/metabolismo , Proteína C-Reativa/metabolismo , Inflamação/imunologia , Componente Amiloide P Sérico/metabolismo , Anticorpos/imunologia , Proteína C-Reativa/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Inflamação/metabolismo , Inflamação/microbiologia , Macrófagos/imunologia , Macrófagos/metabolismo , Redes e Vias Metabólicas/imunologia , Receptores Fc/metabolismo , Componente Amiloide P Sérico/imunologia , Transdução de Sinais/imunologia
2.
Res Vet Sci ; 136: 527-534, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33882381

RESUMO

Oxytocin is currently of high interest as a biomarker of welfare and stress in humans and animals. The purpose of this study was to validate two new assays (one using a monoclonal antibody and the other using a polyclonal antibody) for the oxytocin measurement in the saliva of dogs. For this purpose, an analytical validation was performed, and these assays were applied in an experimental trial in which dogs were stroked by their owners. In the experimental trial, saliva samples of 17 dogs were collected by the owners at three different times: a basal sample, at the end of 10 min of an affiliative interaction with their owners consisting of stroking and 15 min after the end of the affiliative interaction. The dogs were separated into two groups (group 1, n = 8 and group 2, n = 9) according to the acceptance of the sponge and the response to the stroking. Significant differences in the response of salivary oxytocin after stroking in the two groups were found when the assay with the monoclonal antibody was used. This assay showed a significant increase just after the end of affiliative interaction (P < 0.01) and 15 min after (P < 0.01) in those dogs that had a good acceptance of the sponge and the stroking induced a positive response on them (based in a Likert-type scale from 1 to 10). These data reflect that the assays used in this study can lead to different results when quantifying oxytocin in the saliva of dogs after stroking.


Assuntos
Cães/fisiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Ocitocina/análise , Animais de Estimação/fisiologia , Saliva/química , Animais , Anticorpos/imunologia , Anticorpos Monoclonais/imunologia , Biomarcadores , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Masculino
3.
J Med Chem ; 64(8): 4947-4959, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33825469

RESUMO

Hapten-specific endogenous antibodies are naturally occurring antibodies present in human blood. Herein, we investigated a new strategy in which small-molecule haptens were utilized as naturally occurring antibody binders for peptide half-life extension. The glucagon-like peptide 1 receptor agonist exendin 4 was site-specifically functionalized with the dinitrophenyl (DNP) hapten at the C-terminus via sortase A-mediated ligation. The resulting Ex4-DNP conjugates retained GLP-1 receptor activation potency in vitro and had a similar in vivo acute glucose-lowering effect comparable to that of native Ex4. Pharmacokinetic studies and hypoglycemic duration tests demonstrated that the Ex4-DNP conjugates displayed significantly elongated half-lives and improved long-acting antidiabetic activity in the presence of endogenous anti-DNP antibodies. In chronic treatment studies, once-daily administration of optimal conjugate 7 demonstrated more beneficial effects without prominent toxicity compared with Ex4. This strategy provides a new approach and represents an alternative to the well-established peptide-Fc fusion strategy to improve the peptide half-life and the therapeutic efficacy.


Assuntos
Anticorpos/sangue , Exenatida/química , Haptenos/química , Hipoglicemiantes/síntese química , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Complexo Antígeno-Anticorpo/química , Complexo Antígeno-Anticorpo/metabolismo , Glicemia/análise , Diabetes Mellitus Experimental/tratamento farmacológico , Dinitrobenzenos/química , Dinitrobenzenos/imunologia , Desenho de Fármacos , Feminino , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Teste de Tolerância a Glucose , Meia-Vida , Haptenos/imunologia , Hipoglicemiantes/metabolismo , Hipoglicemiantes/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL
4.
Science ; 372(6537)2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33795432

RESUMO

Multivalent display of receptor-engaging antibodies or ligands can enhance their activity. Instead of achieving multivalency by attachment to preexisting scaffolds, here we unite form and function by the computational design of nanocages in which one structural component is an antibody or Fc-ligand fusion and the second is a designed antibody-binding homo-oligomer that drives nanocage assembly. Structures of eight nanocages determined by electron microscopy spanning dihedral, tetrahedral, octahedral, and icosahedral architectures with 2, 6, 12, and 30 antibodies per nanocage, respectively, closely match the corresponding computational models. Antibody nanocages targeting cell surface receptors enhance signaling compared with free antibodies or Fc-fusions in death receptor 5 (DR5)-mediated apoptosis, angiopoietin-1 receptor (Tie2)-mediated angiogenesis, CD40 activation, and T cell proliferation. Nanocage assembly also increases severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus neutralization by α-SARS-CoV-2 monoclonal antibodies and Fc-angiotensin-converting enzyme 2 (ACE2) fusion proteins.


Assuntos
Anticorpos/química , Anticorpos/imunologia , Nanoestruturas , Engenharia de Proteínas , Transdução de Sinais , Angiopoietinas/química , Angiopoietinas/imunologia , Angiopoietinas/metabolismo , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Antígenos CD40/química , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Simulação por Computador , Genes Sintéticos , Humanos , Fragmentos Fc das Imunoglobulinas/química , Ativação Linfocitária , Modelos Moleculares , Ligação Proteica , Receptor TIE-2/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Linfócitos T/fisiologia
5.
Nat Commun ; 12(1): 2425, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893275

RESUMO

Anti-programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) antibodies are currently used in the clinic to interupt the PD-1/PD-L1 immune checkpoint, which reverses T cell dysfunction/exhaustion and shows success in treating cancer. Here, we report a histone demethylase inhibitor, 5-carboxy-8-hydroxyquinoline (IOX1), which inhibits tumour histone demethylase Jumonji domain-containing 1A (JMJD1A) and thus downregulates its downstream ß-catenin and subsequent PD-L1, providing an antibody-independent paradigm interrupting the PD-1/PD-L1 checkpoint. Synergistically, IOX1 inhibits cancer cells' P-glycoproteins (P-gp) through the JMJD1A/ß-catenin/P-gp pathway and greatly enhances doxorubicin (DOX)-induced immune-stimulatory immunogenic cell death. As a result, the IOX1 and DOX combination greatly promotes T cell infiltration and activity and significantly reduces tumour immunosuppressive factors. Their liposomal combination reduces the growth of various murine tumours, including subcutaneous, orthotopic, and lung metastasis tumours, and offers a long-term immunological memory function against tumour rechallenging. This work provides a small molecule-based potent cancer chemo-immunotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doxorrubicina/farmacologia , Hidroxiquinolinas/farmacologia , Imunoterapia/métodos , Neoplasias/terapia , Linfócitos T/efeitos dos fármacos , Animais , Anticorpos/imunologia , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Doxorrubicina/administração & dosagem , Células HCT116 , Humanos , Hidroxiquinolinas/administração & dosagem , Hidroxiquinolinas/química , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células NIH 3T3 , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias Experimentais/imunologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/imunologia
6.
Nat Commun ; 12(1): 2403, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893299

RESUMO

The ability to design functional sequences and predict effects of variation is central to protein engineering and biotherapeutics. State-of-art computational methods rely on models that leverage evolutionary information but are inadequate for important applications where multiple sequence alignments are not robust. Such applications include the prediction of variant effects of indels, disordered proteins, and the design of proteins such as antibodies due to the highly variable complementarity determining regions. We introduce a deep generative model adapted from natural language processing for prediction and design of diverse functional sequences without the need for alignments. The model performs state-of-art prediction of missense and indel effects and we successfully design and test a diverse 105-nanobody library that shows better expression than a 1000-fold larger synthetic library. Our results demonstrate the power of the alignment-free autoregressive model in generalizing to regions of sequence space traditionally considered beyond the reach of prediction and design.


Assuntos
Algoritmos , Biologia Computacional/métodos , Redes Neurais de Computação , Engenharia de Proteínas/métodos , Sequência de Aminoácidos , Anticorpos/genética , Anticorpos/imunologia , Anticorpos/metabolismo , Antígenos/imunologia , Genótipo , Humanos , Mutação , Fenótipo , Proteínas/genética , Proteínas/imunologia , Proteínas/metabolismo
7.
Int J Mol Sci ; 22(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917390

RESUMO

Glycosphingolipids (GSLs) are composed of a mono-, di-, or oligosaccharide and a ceramide and function as constituents of cell membranes. Various molecular species of GSLs have been identified in mammalian cells due to differences in the structures of oligosaccharides. The oligosaccharide structure can vary depending on cell lineage, differentiation stage, and pathology; this property can be used as a cell identification marker. Furthermore, GSLs are involved in various aspects of the immune response, such as cytokine production, immune signaling, migration of immune cells, and antibody production. GSLs containing certain structures exhibit strong immunogenicity in immunized animals and promote the production of anti-GSL antibodies. By exploiting this property, it is possible to generate antibodies that recognize the fine oligosaccharide structure of specific GSLs or glycoproteins. In our study using artificially synthesized GSLs (artGSLs), we found that several structural features are correlated with the antibody-inducing activity of GSLs. Based on these findings, we designed artGSLs that efficiently induce the production of antibodies accompanied by class switching and developed several antibodies that recognize not only certain glycan structures of GSLs but also those of glycoproteins. This review comprehensively introduces the immune activities of GSLs and their application as pharmaceuticals.


Assuntos
Anticorpos/imunologia , Formação de Anticorpos , Movimento Celular , Glicoesfingolipídeos/farmacologia , Switching de Imunoglobulina/efeitos dos fármacos , Transdução de Sinais , Animais , Formação de Anticorpos/efeitos dos fármacos , Formação de Anticorpos/imunologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Citocinas/imunologia , Glicoesfingolipídeos/química , Glicoesfingolipídeos/imunologia , Humanos , Transdução de Sinais/imunologia
8.
Int J Mol Sci ; 22(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923551

RESUMO

Most antibodies currently in use have been selected based on their binding affinity. However, nowadays, antibodies that can not only bind but can also alter the function of cell surface signaling components are increasingly sought after as therapeutic drugs. Therefore, the identification of such functional antibodies from a large antibody library is the subject of intensive research. New methods applied to combinatorial antibody libraries now allow the isolation of functional antibodies in the cellular environment. These selected agonist antibodies have provided new insights into important issues of signal transduction. Notably, when certain antibodies bind to a given receptor, the cell fate induced by them may be the same or different from that induced by natural agonists. In addition, combined with phenotypic screening, this platform allows us to discover unexpected experimental results and explore various phenomena in cell biology, such as those associated with stem cells and cancer cells.


Assuntos
Anticorpos/imunologia , Descoberta de Drogas/métodos , Biblioteca de Peptídeos , Receptores Acoplados a Proteínas G/imunologia , Animais , Anticorpos/genética , Pleiotropia Genética , Humanos , Receptores Acoplados a Proteínas G/genética
9.
J Med Chem ; 64(5): 2382-2418, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33650861

RESUMO

Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, but an effective targeted therapy has not been well-established so far. Considering the lack of effective targets, where do we go next in the current TNBC drug development? A promising intervention for TNBC might lie in de novo small-molecule drugs that precisely target different molecular characteristics of TNBC. However, an ideal single-target drug discovery still faces a huge challenge. Alternatively, other new emerging strategies, such as dual-target drug, drug repurposing, and combination strategies, may provide new insight into the improvement of TNBC therapeutics. In this review, we focus on summarizing the current situation of a series of candidate small-molecule drugs in TNBC therapy, including single-target drugs, dual-target drugs, as well as drug repurposing and combination strategies that will together shed new light on the future directions targeting TNBC vulnerabilities with small-molecule drugs for future therapeutic purposes.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Anticorpos/imunologia , Anticorpos/uso terapêutico , Antineoplásicos/química , Ensaios Clínicos como Assunto , Combinação de Medicamentos , Descoberta de Drogas , Reposicionamento de Medicamentos , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/uso terapêutico , Terapia de Alvo Molecular , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/terapia
10.
PLoS One ; 16(3): e0245424, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33760825

RESUMO

SARS-CoV-2 (Severe Acute Respiratory Syndrome Corona Virus-2), cause of COVID-19 (Coronavirus Disease of 2019), represents a significant risk to people living with pre-existing conditions associated with exacerbated inflammatory responses and consequent dysfunctional immunity. In this paper, we have evaluated the influence of obesity, a condition associated with chronic systemic inflammation, on the secretion of SARS-CoV-2-specific IgG antibodies in the blood of COVID-19 patients. Our hypothesis is that obesity is associated with reduced amounts of specific IgG antibodies. Results have confirmed our hypothesis and have shown that SARS-CoV-2 IgG antibodies are negatively associated with Body Mass Index (BMI) in COVID-19 obese patients, as expected based on the known influence of obesity on humoral immunity. Antibodies in COVID-19 obese patients are also negatively associated with serum levels of pro-inflammatory and metabolic markers of inflammaging and pulmonary inflammation, such as SAA (serum amyloid A protein), CRP (C-reactive protein), and ferritin, but positively associated with NEFA (nonesterified fatty acids). These results altogether could help to identify an inflammatory signature with strong predictive value for immune dysfunction. Inflammatory markers identified may subsequently be targeted to improve humoral immunity in individuals with obesity and in individuals with other chronic inflammatory conditions.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , Obesidade/virologia , Adulto , Idoso , Anticorpos/sangue , Anticorpos/imunologia , Anticorpos Antivirais/sangue , Biomarcadores/sangue , Índice de Massa Corporal , COVID-19/sangue , COVID-19/epidemiologia , Infecções por Coronavirus/virologia , Feminino , Humanos , Imunidade Humoral/imunologia , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade
11.
Int J Mol Sci ; 22(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672018

RESUMO

Hepatitis B is a major global health challenge. In the absence of an effective treatment for the disease, hepatitis B vaccines provide protection against the viral infection. However, some individuals do not have positive immune responses after being vaccinated with the hepatitis B vaccines available in the market. Thus, it is important to develop a more protective vaccine. Previously, we showed that hepatitis B virus (HBV) 'a' determinant (aD) displayed on the prawn nodavirus capsid (Nc) and expressed in Spodoptera frugiperda (Sf9) cells (namely, Nc-aD-Sf9) self-assembled into virus-like particles (VLPs). Immunisation of BALB/c mice with the Nc-aD-Sf9 VLPs showed significant induction of humoral, cellular and memory B-cell immunity. In the present study, the biophysical properties of the Nc-aD-Sf9 VLPs were studied using dynamic light scattering (DLS) and circular dichroism (CD) spectroscopy. Enzyme-linked immunosorbent assay (ELISA) was used to determine the antigenicity of the Nc-aD-Sf9 VLPs, and multiplex ELISA was employed to quantify the cytokine response induced by the VLPs administered intramuscularly into BALB/c mice (n = 8). CD spectroscopy of Nc-aD-Sf9 VLPs showed that the secondary structure of the VLPs predominantly consisted of beta (ß)-sheets (44.8%), and they were thermally stable up to ~52 °C. ELISA revealed that the aD epitope of the VLPs was significantly antigenic to anti-HBV surface antigen (HBsAg) antibodies. In addition, multiplex ELISA of serum samples from the vaccinated mice showed a significant induction (p < 0.001) of IFN-γ, IL-4, IL-5, IL-6, IL-10, and IL-12p70. This cytokine profile is indicative of natural killer cell, macrophage, dendritic cell and cytotoxic T-lymphocyte activities, which suggests a prophylactic innate and adaptive cellular immune response mediated by Nc-aD-Sf9 VLPs. Interestingly, Nc-aD-Sf9 induced a more robust release of the aforementioned cytokines than that of Nc-aD VLPs produced in Escherichia coli and a commercially used hepatitis B vaccine. Overall, Nc-aD-Sf9 VLPs are thermally stable and significantly antigenic, demonstrating their potential as an HBV vaccine candidate.


Assuntos
Proteínas do Capsídeo/imunologia , Citocinas/metabolismo , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Epitopos Imunodominantes/imunologia , Nodaviridae/imunologia , Transdução de Sinais/imunologia , Vacinação/métodos , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Anticorpos/imunologia , Antígenos de Superfície da Hepatite B/imunologia , Vacinas contra Hepatite B/administração & dosagem , Temperatura Alta , Camundongos , Camundongos Endogâmicos BALB C , Células Sf9 , Spodoptera , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem
12.
Int J Mol Sci ; 22(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652936

RESUMO

Human cytomegalovirus (CMV) infection is widespread among adults (60-90%) and is usually undetected in healthy individuals without symptoms but can cause severe diseases in immunocompromised hosts. T-cell receptor (TCR)-like antibodies (Abs), which recognize complex antigens (peptide-MHC complex, pMHC) composed of MHC molecules with embedded short peptides derived from intracellular proteins, including pathogenic viral proteins, can serve as diagnostic and/or therapeutic agents. In this study, we aimed to engineer a TCR-like Ab specific for pMHC comprising a CMV pp65 protein-derived peptide (495NLVPMVATV503; hereafter, CMVpp65495-503) in complex with MHC-I molecule human leukocyte antigen (HLA)-A*02:01 (CMVpp65495-503/HLA-A*02:01) to increase affinity by sequential mutagenesis of complementarity-determining regions using yeast surface display technology. Compared with the parental Ab, the final generated Ab (C1-17) showed ~67-fold enhanced binding affinity (KD ≈ 5.2 nM) for the soluble pMHC, thereby detecting the cell surface-displayed CMVpp65495-503/HLA-A*02:01 complex with high sensitivity and exquisite specificity. Thus, the new high-affinity TCR-like Ab may be used for the detection and treatment of CMV infection.


Assuntos
Anticorpos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Antígenos HLA-A/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas da Matriz Viral/imunologia , Afinidade de Anticorpos , Linhagem Celular , Humanos , Peptídeos/imunologia
13.
Methods Mol Biol ; 2265: 223-233, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704718

RESUMO

The advent of personalized medicines targeting cell signaling pathways has radically improved melanoma patient outcomes. More recently, immune-modulating therapies disrupting the PD-1/PD-L1 axis have become a powerful tool in the treatment of a range of melanoma, showing a profound improvement in the overall survival outcomes. However, immune checkpoint inhibitors (ICIs) are associated with considerable toxicities and appear to only be efficacious in a subset of melanoma patients. Therefore, there is an urgent need to identify biomarkers that can determine if patients will or will not respond to ICI therapy. Here, we describe an optimized method for analyzing PD-L1 expression on circulating melanoma cells following immunomagnetic enrichment from patient blood samples.


Assuntos
Antígeno B7-H1/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Separação Imunomagnética/métodos , Melanoma/sangue , Células Neoplásicas Circulantes/imunologia , Anticorpos/imunologia , Antígeno B7-H1/imunologia , Humanos , Leucócitos Mononucleares/citologia , Biópsia Líquida/métodos , Melanoma/diagnóstico
14.
Nutrients ; 13(3)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652629

RESUMO

Impaired gastric digestion due to suppressed gastric acidity enhances the risk for food allergy development. In the current study, we aimed to evaluate the impact of a supported gastric digestion via application of a pharmaceutical gastric enzyme solution (GES) on food allergy development and allergic reactions in a BALB/c mouse model. The ability of the GES to restore hypoacidic conditions was tested in mice treated with gastric acid suppression medication. To evaluate the impact on allergic symptoms, mice were orally sensitized with ovalbumin (OVA) under gastric acid suppression and subjected to oral challenges with or without GES. The immune response was evaluated by measurement of antibody titers, cytokine levels, mucosal allergy effector cell influx and regulatory T-cell counts. Clinical response was objectified by core body temperature measurements after oral OVA challenge. Supplementation of GES transiently restored physiological pH levels in the stomach after pharmaceutical gastric acid suppression. During oral sensitization, supplementation of gastric enzymes significantly reduced systemic IgE, IgG1 and IgG2a levels and allergic symptoms. In food allergic mice, clinical symptoms were reduced by co-administration of the gastric enzyme solution. Support of gastric digestion efficiently prevents food allergy induction and alleviates clinical symptoms in our food allergy model.


Assuntos
Suplementos Nutricionais , Digestão/imunologia , Hipersensibilidade Alimentar/prevenção & controle , Fármacos Gastrointestinais/administração & dosagem , Tolerância Imunológica/efeitos dos fármacos , Alérgenos/imunologia , Animais , Anticorpos/sangue , Anticorpos/imunologia , Subpopulações de Linfócitos B/imunologia , Citocinas/sangue , Citocinas/imunologia , Modelos Animais de Doenças , Hipersensibilidade Alimentar/imunologia , Contagem de Linfócitos , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Estômago/imunologia , Linfócitos T Reguladores/imunologia
16.
Int J Infect Dis ; 104: 610-616, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33524620

RESUMO

AIM: The antibody levels against a broad spectrum of pathogens were assessed in commercial intravenous immunoglobulin (IVIG) manufactured from pooled plasma obtained from different global regions. METHODS: Twenty-four IVIG commercial lots from eight manufacturers corresponding to 12 brands were analyzed. The plasma was collected in 10 countries/regions. Depending on each pathogen, antibody levels were measured using specific commercial IgG-specific enzyme immunoassay kits or by cell culture neutralization test and guinea pig skin neutralization test. A principal component analysis was performed. RESULTS: For polio and diphtheria (reference markers of the US authorities), all IVIGs had relevant titers in accordance with reference levels. IVIGs from Canada, Australia, and the USA were positive for titers against globally distributed pathogens or those under vaccination programs in the developed world (parainfluenza, Epstein-Barr, varicella-zoster, influenza B, parvovirus B19, and measles viruses). IVIG from Taiwan and Hong Kong showed low antibody titers for these pathogens but high titers for Pseudomonas aeruginosa. IVIG from India had high titers for pathogens frequently found in developing countries (West Nile, dengue, chikungunya, and hepatitis E viruses and Streptococcus pneumoniae). IVIGs from Argentina, Spain, Israel, and Czechia showed intermediate antibody concentrations. CONCLUSION: The antibody profile in IVIG was greatly influenced by regional characteristics including climate, vaccination programs, and the prevalence of pathogens in the different countries and regions.


Assuntos
Imunoglobulinas Intravenosas/imunologia , América , Anticorpos/genética , Anticorpos/imunologia , Ásia , Humanos , Técnicas Imunoenzimáticas , Imunoglobulinas Intravenosas/análise , Imunoglobulinas Intravenosas/economia , Testes de Neutralização , Plasma/química , Plasma/imunologia
17.
Cancer Sci ; 112(4): 1417-1428, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33539630

RESUMO

Chimeric antigen receptor (CAR)-T cell therapy has shown salient efficacy in cancer immunotherapy, particularly in the treatment of B cell malignancies. However, the efficacy of CAR-T for solid tumors remains inadequate. In this study, we displayed that c-met is an appropriate therapeutic target for papillary renal cell carcinoma (PRCC) using clinical samples, developed an anti-human c-met CAR-T cells, and investigated the anti-tumor efficacy of the CAR-T cells using an orthotopic mouse model as pre-clinical research. Administration of the anti-c-met CAR-T cells induced marked infiltration of the CAR-T cells into the tumor tissue and unambiguous suppression of tumor growth. Furthermore, in combination with axitinib, the anti-tumor efficacy of the CAR-T cells was synergistically augmented. Taken together, our current study demonstrated the potential for clinical application of anti-c-met CAR-T cells in the treatment of patients with PRCC.


Assuntos
Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/terapia , Neoplasias Renais/imunologia , Neoplasias Renais/terapia , Proteínas Proto-Oncogênicas c-met/imunologia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Idoso , Animais , Anticorpos/imunologia , Antígenos de Neoplasias/imunologia , Linhagem Celular Tumoral , Células Cultivadas , Modelos Animais de Doenças , Feminino , Humanos , Imunoterapia/métodos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
18.
Food Chem ; 345: 128812, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33601655

RESUMO

Due to complex matrixes and specific reagent deficiency, the rapid detection of histamine is still a challenge to date. Based on the high peroxidase-like activity of iron-cobalt co-doped carbon dots, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was established for histamine detection using the mimic enzyme labeled with histamine antibody (His-Ab). Through the competitive binding of the labeled His-Ab to solid-phase and sample antigens, histamine content was detected with a linear range of 2.5-150 µg mL-1. The detection limit based on 3σ/K was 0.50 mg kg-1, which was much lower than those of commercial His-kit and HPLC methods. The ic-ELISA method was applied to histamine detection in fish samples with the recovery of (103.4 ± 0.5)%, which was in accord with those of commercial His-kit and HPLC methods. The results indicated that the established ic-ELISA method was suitable for rapid detection of histamine in fish samples with high accuracy, sensitivity and stability.


Assuntos
Peixes/metabolismo , Histamina/análise , Pontos Quânticos/química , Animais , Anticorpos/química , Anticorpos/imunologia , Carbono/química , Cobalto/química , Ensaio de Imunoadsorção Enzimática , Histamina/imunologia , Ferro/química , Limite de Detecção , Reprodutibilidade dos Testes , Alimentos Marinhos/análise
19.
Food Chem ; 350: 129229, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33636619

RESUMO

A new strategy to mimic antibody for electrochemical recognition and detection of deoxynivalenol (DON) using a highly-sensitive and selective antibody-like sensor based on molecularly imprinted poly(l-arginine) (P-Arg-MIP) on carboxylic acid functionalized carbon nanotubes (COOH-MWCNTs) was proposed. l-arginine as functional monomer was screened to prepare imprinted electrode via its electro-polymerization in the presence of DON onto the surface of COOH-MWCNTs electrode coupled with theoretical calculation. Surface morphology, structural characteristics, and electrochemical properties of P-Arg-MIP/COOH-MWCNTs were characterized by SEM, EDS, FTIR, and CV, respectively. P-Arg-MIP/COOH-MWCNTs displayed relatively high conductivity, high effective surface area, antibody-like molecular recognition and affinity, and a good response towards DON in a linear range from 0.1 to 70 µM with LOD of 0.07 µM in wheat flour samples with satisfactory recovery and feasible practicability in comparison with HPLC. This method provides a promising biomimetic sensing platform for the determination of mycotoxins in food and agro-products.


Assuntos
Biomimética/instrumentação , Limite de Detecção , Impressão Molecular , Nanotubos de Carbono/química , Peptídeos/química , Peptídeos/síntese química , Tricotecenos/análise , Anticorpos/imunologia , Eletroquímica , Eletrodos , Farinha/análise , Tricotecenos/química , Triticum/química
20.
Nat Chem Biol ; 17(4): 428-437, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33542533

RESUMO

Tryptophan C-mannosylation is an unusual co-translational protein modification performed by metazoans and apicomplexan protists. The prevalence and biological functions of this modification are poorly understood, with progress in the field hampered by a dearth of convenient tools for installing and detecting the modification. Here, we engineer a yeast system to produce a diverse array of proteins with and without tryptophan C-mannosylation and interrogate the modification's influence on protein stability and function. This system also enabled mutagenesis studies to identify residues of the glycosyltransferase and its protein substrates that are crucial for catalysis. The collection of modified proteins accrued during this work facilitated the generation and thorough characterization of monoclonal antibodies against tryptophan C-mannosylation. These antibodies empowered proteomic analyses of the brain C-glycome by enriching for peptides possessing tryptophan C-mannosylation. This study revealed many new modification sites on proteins throughout the secretory pathway with both conventional and non-canonical consensus sequences.


Assuntos
Manose/química , Engenharia de Proteínas/métodos , Triptofano/metabolismo , Sequência de Aminoácidos/genética , Anticorpos/imunologia , Glicosilação , Glicosiltransferases/metabolismo , Manose/metabolismo , Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Estabilidade Proteica , Proteômica/métodos , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo , Triptofano/química
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