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2.
Nat Commun ; 12(1): 4864, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381030

RESUMO

Successful therapeutics and vaccines for coronavirus disease 2019 (COVID-19) have harnessed the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Evidence that SARS-CoV-2 exists as locally evolving variants suggests that immunological differences may impact the effectiveness of antibody-based treatments such as convalescent plasma and vaccines. Considering that near-sourced convalescent plasma likely reflects the antigenic composition of local viral strains, we hypothesize that convalescent plasma has a higher efficacy, as defined by death within 30 days of transfusion, when the convalescent plasma donor and treated patient were in close geographic proximity. Results of a series of modeling techniques applied to approximately 28,000 patients from the Expanded Access to Convalescent Plasma program (ClinicalTrials.gov number: NCT04338360) support this hypothesis. This work has implications for the interpretation of clinical studies, the ability to develop effective COVID-19 treatments, and, potentially, for the effectiveness of COVID-19 vaccines as additional locally-evolving variants continue to emerge.


Assuntos
COVID-19/terapia , Plasma/imunologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Variação Antigênica , Doadores de Sangue , COVID-19/mortalidade , Feminino , Humanos , Imunização Passiva/mortalidade , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto Jovem
3.
Int J Mol Sci ; 22(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34445637

RESUMO

DNA is a polymeric macromolecule that can display a variety of backbone conformations. While the classical B-DNA is a right-handed double helix, Z-DNA is a left-handed helix with a zig-zag orientation. The Z conformation depends upon the base sequence, base modification and supercoiling and is considered to be transient. To determine whether the presence of Z-DNA can be detected immunochemically, the binding of monoclonal and polyclonal anti-Z-DNA antibodies to a panel of natural DNA antigens was assessed by an ELISA using brominated poly(dG-dC) as a control for Z-DNA. As these studies showed, among natural DNA tested (Micrococcus luteus, calf thymus, Escherichiacoli, salmon sperm, lambda phage), micrococcal (MC) DNA showed the highest binding with both anti-Z-DNA preparations, and E. coli DNA showed binding with the monoclonal anti-DNA preparation. The specificity for Z-DNA conformation in MC DNA was demonstrated by an inhibition binding assay. An algorithm to identify propensity to form Z-DNA indicated that DNA from Mycobacterium tuberculosis could form Z-DNA, a prediction confirmed by immunoassay. Together, these findings indicate that anti-Z-DNA antibodies can serve as probes for the presence of Z-DNA in DNA of various species origin and that the content of Z-DNA varies significantly among DNA sources.


Assuntos
Anticorpos Monoclonais/metabolismo , Especificidade de Anticorpos , DNA Forma Z/metabolismo , Escherichia coli/imunologia , Micrococcus luteus/imunologia , Placenta/imunologia , Espermatozoides/imunologia , Animais , Anticorpos Monoclonais/imunologia , DNA Forma Z/química , DNA Forma Z/imunologia , Escherichia coli/metabolismo , Feminino , Humanos , Masculino , Micrococcus luteus/metabolismo , Conformação de Ácido Nucleico , Placenta/metabolismo , Gravidez , Salmão , Ovinos , Especificidade da Espécie , Espermatozoides/metabolismo
4.
Immunology ; 164(1): 1-2, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34382228

RESUMO

Mass vaccination of the global population against SARS-CoV-2 will, we hope, turn the tide against this devastating pandemic. To complement vaccinations, better tools are needed to enable viral infections and immunological protection to be monitored. Accurate tools provide sound data for informed decision-making at many levels, from personal to governmental. The measurement of viral RNA is currently routinely used to detect active infections, but only gives a positive result during infection and is unable to reveal historic infections. Tests involving a detection of SARS-CoV-2-specific antibodies can reveal prior exposures to virus and can measure anti-viral immune responses induced after natural infection or after vaccination. They may eventually also be used to predict an individual's likelihood of becoming re-infected. Here, we report on the development of a sensitive ELISA technique to detect multiple isotypes of antibodies against the spike glycoprotein, in samples of both serum and saliva. This paper provides an important step towards understanding the immune response to SARS-CoV-2 and may therefore eventually help us to effectively control it.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Antivirais/sangue , Especificidade de Anticorpos , COVID-19/sangue , COVID-19/diagnóstico , Suscetibilidade a Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Interações Hospedeiro-Patógeno/imunologia , Humanos , Biópsia Líquida , Sensibilidade e Especificidade , Carga Viral
5.
J Autoimmun ; 123: 102706, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34293683

RESUMO

Autoimmune phenomena and clinically apparent autoimmune diseases, including autoimmune hepatitis, are increasingly been reported not only after natural infection with the SARS-CoV-2 virus, but also after vaccination against it. We report the case of a 63-year old man without a history of autoimmunity or SARS-CoV-2 natural infection who experienced acute severe autoimmune-like hepatitis seven days after the first dose of the mRNA-1273 SARS-CoV-2 vaccine. Liver histology showed inflammatory portal infiltrate with interface hepatitis, lobular and centrilobular inflammation with centrilobular necrosis, in absence of fibrosis and steatosis. Serum immunoglobulin G was slightly elevated. Autoimmune liver serology showed an indirect immunofluorescence pattern on triple rodent tissue compatible with anti-mitochondrial antibody (AMA), but, unexpectedly, this pattern was not mirrored by positivity for primary biliary cholangitis (PBC)-specific molecular tests, indicating that this antibody is different from classical AMA. Anti-nuclear antibody (ANA) was also positive with a rim-like indirect immunofluorescence pattern on liver and HEp2 cell substrates, similar to PBC-specific ANA; however, anti-gp210 and a large panel of molecular-based assays for nuclear antigens were negative, suggesting a unique ANA in our patient. He carries the HLA DRB1*11:01 allele, which is protective against PBC. Response to prednisone treatment was satisfactory. The clinical significance of these novel specificities needs to be further evaluated in this emerging condition.


Assuntos
Autoanticorpos/imunologia , Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Cadeias HLA-DRB1/imunologia , Hepatite Autoimune/etiologia , Mitocôndrias/imunologia , SARS-CoV-2/imunologia , Vacinação/efeitos adversos , Animais , Anticorpos Antinucleares/imunologia , Especificidade de Anticorpos , Autoantígenos/imunologia , Linhagem Celular , Técnica Indireta de Fluorescência para Anticorpo , Hepatite Autoimune/tratamento farmacológico , Hepatite Autoimune/imunologia , Hepatite Autoimune/patologia , Humanos , Imunossupressores/uso terapêutico , Fígado/imunologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Rosuvastatina Cálcica/efeitos adversos , Rosuvastatina Cálcica/uso terapêutico
6.
Infect Immun ; 89(9): e0021721, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34228490

RESUMO

Cholera is a diarrheal disease caused by Vibrio cholerae that continues to be a major public health concern in populations without access to safe water. IgG- and IgA-secreting memory B cells (MBC) targeting the V. cholerae O-specific polysaccharide (OSP) correlate with protection from infection in persons exposed to V. cholerae and may be a major determinant of long-term protection against cholera. Shanchol, a widely used oral cholera vaccine (OCV), stimulates OSP MBC responses in only some people after vaccination, and the gut microbiota is a possible determinant of variable immune responses observed after OCV. Using 16S rRNA sequencing of feces from the time of vaccination, we compared the gut microbiota among adults with and without MBC responses to OCV. Gut microbial diversity measures were not associated with MBC isotype or OSP-specific responses, but individuals with a higher abundance of Clostridiales and lower abundance of Enterobacterales were more likely to develop an MBC response. We applied protein-normalized fecal supernatants of high and low MBC responders to THP-1-derived human macrophages to investigate the effect of microbial factors at the time of vaccination. Feces from individuals with higher MBC responses induced significantly different IL-1ß and IL-6 levels than individuals with lower responses, indicating that the gut microbiota at the time of vaccination may "prime" the mucosal immune response to vaccine antigens. Our results suggest the gut microbiota could impact immune responses to OCVs, and further study of microbial metabolites as potential vaccine adjuvants is warranted.


Assuntos
Linfócitos B/imunologia , Vacinas contra Cólera/imunologia , Cólera/imunologia , Cólera/microbiologia , Microbioma Gastrointestinal , Memória Imunológica , Vibrio cholerae/imunologia , Administração Oral , Adolescente , Adulto , Especificidade de Anticorpos/imunologia , Linfócitos B/metabolismo , Cólera/prevenção & controle , Vacinas contra Cólera/administração & dosagem , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , Interações Microbianas , Vacinação , Adulto Jovem
7.
Immunity ; 54(8): 1841-1852.e4, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246326

RESUMO

Antibody titers against SARS-CoV-2 slowly wane over time. Here, we examined how time affects antibody potency. To assess the impact of antibody maturation on durable neutralizing activity against original SARS-CoV-2 and emerging variants of concern (VOCs), we analyzed receptor binding domain (RBD)-specific IgG antibodies in convalescent plasma taken 1-10 months after SARS-CoV-2 infection. Longitudinal evaluation of total RBD IgG and neutralizing antibody revealed declining total antibody titers but improved neutralization potency per antibody to original SARS-CoV-2, indicative of antibody response maturation. Neutralization assays with authentic viruses revealed that early antibodies capable of neutralizing original SARS-CoV-2 had limited reactivity toward B.1.351 (501Y.V2) and P.1 (501Y.V3) variants. Antibodies from late convalescents exhibited increased neutralization potency to VOCs, suggesting persistence of cross-neutralizing antibodies in plasma. Thus, maturation of the antibody response to SARS-CoV-2 potentiates cross-neutralizing ability to circulating variants, suggesting that declining antibody titers may not be indicative of declining protection.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , COVID-19/epidemiologia , Humanos , Imunoglobulina G , Testes de Neutralização , SARS-CoV-2/genética , Carga Viral
8.
Biochem Biophys Res Commun ; 571: 152-158, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34325131

RESUMO

Potent neutralizing antibodies (Abs) have been proven with therapeutic efficacy for the intervention against SARS-CoV-2. Majority of these Abs function by directly interfering with the virus entry to host cells. Here, we identified a receptor binding domain (RBD) specific monoclonal Ab (mAb) 82A6 with efficient neutralizing potency against authentic SARS-CoV-2 virus. As most Abs targeting the non-receptor binding motif (RBM) region, 82A6 was incapable to block the RBD-ACE2 interaction. In particular, it actively promoted the S1 subunit shedding from the S protein, which may lead to effective reduction of intact SARS-CoV-2 viruses. Importantly, it could block potential syncytia formation associated with post-infectious cell surface expression of S proteins. Our study evidenced a RBD specific Ab with unique beneficial efficacy against SARS-CoV-2 infection, which might bring informative significance to understand the collective effects of neutralizing Abs elicited in COVID-19 patients.


Assuntos
Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , COVID-19/terapia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Monoclonais/uso terapêutico , Especificidade de Anticorpos , Sítios de Ligação/imunologia , COVID-19/imunologia , COVID-19/virologia , Células Gigantes/imunologia , Células Gigantes/virologia , Células HEK293 , Humanos , Imunização Passiva , Técnicas In Vitro , Domínios Proteicos , Subunidades Proteicas , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/química , Eliminação de Partículas Virais
9.
EBioMedicine ; 69: 103478, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34256345

RESUMO

BACKGROUND: Approximately 40% of human pregnancies are unintended, indicating a need for more acceptable effective contraception methods. New antibody production systems make it possible to manufacture reagent-grade human monoclonal antibodies (mAbs) for clinical use. We used the Nicotiana platform to produce a human antisperm mAb and tested its efficacy for on-demand topical contraception. METHODS: Heavy and light chain variable region DNA sequences of a human IgM antisperm antibody derived from an infertile woman were inserted with human IgG1 constant region sequences into an agrobacterium and transfected into Nicotiana benthamiana. The product, an IgG1 mAb ["Human Contraception Antibody" (HCA)], was purified on Protein A columns, and QC was performed using the LabChip GXII Touch protein characterization system and SEC-HPLC. HCA was tested for antigen specificity by immunofluorescence and western blot assays, antisperm activity by sperm agglutination and complement dependent sperm immobilization assays, and safety in a human vaginal tissue (EpiVaginal™) model. FINDINGS: HCA was obtained at concentrations ranging from 0.4 to 4 mg/ml and consisted of > 90% IgG monomers. The mAb specifically reacted with a glycan epitope on CD52g, a glycoprotein produced in the male reproductive tract and found in abundance on sperm. HCA potently agglutinated sperm under a variety of relevant physiological conditions at concentrations ≥ 6.25 µg/ml, and mediated complement-dependent sperm immobilization at concentrations ≥ 1 µg/ml. HCA and its immune complexes did not induce inflammation in EpiVaginal™ tissue. INTERPRETATION: HCA, an IgG1 mAb with potent sperm agglutination and immobilization activity and a good safety profile, is a promising candidate for female contraception. FUNDING: This research was supported by grants R01 HD095630 and P50HD096957 from the National Institutes of Health.


Assuntos
Anticorpos Monoclonais/imunologia , Antígeno CD52/imunologia , Anticoncepção Imunológica/métodos , Espermatozoides/imunologia , Vacinas Anticoncepcionais/imunologia , Especificidade de Anticorpos , Feminino , Humanos , Masculino
10.
PLoS Pathog ; 17(7): e1009761, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34270631

RESUMO

T-cell immunity is likely to play a role in protection against SARS-CoV-2 by helping generate neutralizing antibodies. We longitudinally studied CD4 T-cell responses to the M, N, and S structural proteins of SARS-CoV-2 in 26 convalescent individuals. Within the first two months following symptom onset, a majority of individuals (81%) mounted at least one CD4 T-cell response, and 48% of individuals mounted detectable SARS-CoV-2-specific circulating T follicular helper cells (cTfh, defined as CXCR5+PD1+ CD4 T cells). SARS-CoV-2-specific cTfh responses across all three protein specificities correlated with antibody neutralization with the strongest correlation observed for S protein-specific responses. When examined over time, cTfh responses, particularly to the M protein, increased in convalescence, and robust cTfh responses with magnitudes greater than 5% were detected at the second convalescent visit, a median of 38 days post-symptom onset. CD4 T-cell responses declined but persisted at low magnitudes three months and six months after symptom onset. These data deepen our understanding of antigen-specific cTfh responses in SARS-CoV-2 infection, suggesting that in addition to S protein, M and N protein-specific cTfh may also assist in the development of neutralizing antibodies and that cTfh response formation may be delayed in SARS-CoV-2 infection.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Células T Auxiliares Foliculares/imunologia , Células T Auxiliares Foliculares/virologia , Adulto , Idoso , Especificidade de Anticorpos , Estudos de Casos e Controles , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Feminino , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pandemias , Fosfoproteínas/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Fatores de Tempo , Proteínas da Matriz Viral/imunologia , Adulto Jovem
11.
PLoS Pathog ; 17(7): e1009766, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34280244

RESUMO

Neutralizing antibodies to the SARS CoV-2 spike proteins have been issued Emergency Use Authorizations and are a likely mechanism of vaccines to prevent COVID-19. However, benefit of treatment with monoclonal antibodies has only been observed in clinical trials in outpatients with mild to moderate COVID-19 but not in patients who are hospitalized and/or have advanced disease. To address this observation, we evaluated the timing of anti SARS-CoV-2 antibody production in hospitalized patients with the use of a highly sensitive multiplexed bead-based immunoassay allowing for early detection of antibodies to SARS-CoV-2. We found significantly lower levels of antibodies to the SARS-CoV-2 spike protein in the first week after symptom onset in patients who expired as compared to patients who were discharged. We also developed a model to characterize the relationship between each patient's individual antibody level trajectory and eventual COVID 19 outcome which can be adapted into a prediction model with more data.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/imunologia , COVID-19/mortalidade , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Especificidade de Anticorpos , Antígenos Virais/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Modelos Imunológicos , Pandemias , Prognóstico , Glicoproteína da Espícula de Coronavírus/imunologia , Fatores de Tempo , Estados Unidos/epidemiologia
12.
Sci Transl Med ; 13(602)2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-34261800

RESUMO

Although substantial progress has been made with Ebola virus (EBOV) vaccine measures, the immune correlates of vaccine-mediated protection remain uncertain. Here, five mucosal vaccine vectors based on human and avian paramyxoviruses provided nonhuman primates with varying degrees of protection, despite expressing the same EBOV glycoprotein (GP) immunogen. Each vaccine produced antibody responses that differed in Fc-mediated functions and isotype composition, as well as in magnitude and coverage toward GP and its conformational and linear epitopes. Differences in the degree of protection and comprehensive characterization of the response afforded the opportunity to identify which features and functions were elevated in survivors and could therefore serve as vaccine correlates of protection. Pairwise network correlation analysis of 139 immune- and vaccine-related parameters was performed to demonstrate relationships with survival. Total GP-specific antibodies, as measured by biolayer interferometry, but not neutralizing IgG or IgA titers, correlated with survival. Fc-mediated functions and the amount of receptor binding domain antibodies were associated with improved survival outcomes, alluding to the protective mechanisms of these vaccines. Therefore, functional qualities of the antibody response, particularly Fc-mediated effects and GP specificity, rather than simply magnitude of the response, appear central to vaccine-induced protection against EBOV. The heterogeneity of the response profile between the vaccines indicates that each vaccine likely exhibits its own protective signature and the requirements for an efficacious EBOV vaccine are complex.


Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Especificidade de Anticorpos , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Primatas
13.
JCI Insight ; 6(13)2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34081630

RESUMO

BACKGROUNDThe role of humoral immunity in COVID-19 is not fully understood, owing, in large part, to the complexity of antibodies produced in response to the SARS-CoV-2 infection. There is a pressing need for serology tests to assess patient-specific antibody response and predict clinical outcome.METHODSUsing SARS-CoV-2 proteome and peptide microarrays, we screened 146 COVID-19 patients' plasma samples to identify antigens and epitopes. This enabled us to develop a master epitope array and an epitope-specific agglutination assay to gauge antibody responses systematically and with high resolution.RESULTSWe identified linear epitopes from the spike (S) and nucleocapsid (N) proteins and showed that the epitopes enabled higher resolution antibody profiling than the S or N protein antigen. Specifically, we found that antibody responses to the S-811-825, S-881-895, and N-156-170 epitopes negatively or positively correlated with clinical severity or patient survival. Moreover, we found that the P681H and S235F mutations associated with the coronavirus variant of concern B.1.1.7 altered the specificity of the corresponding epitopes.CONCLUSIONEpitope-resolved antibody testing not only affords a high-resolution alternative to conventional immunoassays to delineate the complex humoral immunity to SARS-CoV-2 and differentiate between neutralizing and non-neutralizing antibodies, but it also may potentially be used to predict clinical outcome. The epitope peptides can be readily modified to detect antibodies against variants of concern in both the peptide array and latex agglutination formats.FUNDINGOntario Research Fund (ORF) COVID-19 Rapid Research Fund, Toronto COVID-19 Action Fund, Western University, Lawson Health Research Institute, London Health Sciences Foundation, and Academic Medical Organization of Southwestern Ontario (AMOSO) Innovation Fund.


Assuntos
Testes de Aglutinação/métodos , Formação de Anticorpos/imunologia , Teste Sorológico para COVID-19/métodos , COVID-19/imunologia , Epitopos de Linfócito B/imunologia , SARS-CoV-2/imunologia , Sequência de Aminoácidos , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos/imunologia , COVID-19/sangue , COVID-19/mortalidade , Epitopos/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Humanos , Imunidade Humoral , Análise em Microsséries/métodos , Nucleocapsídeo/química , Nucleocapsídeo/genética , Nucleocapsídeo/imunologia , Peptídeos/imunologia , SARS-CoV-2/genética , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia
14.
Transfus Apher Sci ; 60(4): 103174, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34088601

RESUMO

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is associated with high titers of immunoglobulin G class antibodies directed against the cationic platelet chemokine platelet factor 4 (PF4). These antibodies activate platelets via FcγIIa receptors. VITT closely resembles heparin-induced thrombocytopenia. Inflammation and tissue trauma substantially increase the risk for forming pathogenic PF4 antibodies. We therefore propose the use of therapeutic plasma exchange as rescue therapy in VITT to deplete antibodies plus factors promoting inflammation such as excess cytokines in the circulation as well as extracellular vesicles derived from activated platelets.


Assuntos
Vacinas contra COVID-19/efeitos adversos , Troca Plasmática , Fator Plaquetário 4/imunologia , Púrpura Trombocitopênica Trombótica/terapia , Terapia de Salvação , Albuminas , Especificidade de Anticorpos , Anticoagulantes , Autoanticorpos/imunologia , Vacinas contra COVID-19/farmacologia , Citratos , Contraindicações de Procedimentos , Citocinas/sangue , Vesículas Extracelulares , Humanos , Imunoglobulina G/imunologia , Imunossupressão , Inflamação , Troca Plasmática/efeitos adversos , Troca Plasmática/métodos , Ativação Plaquetária , Transfusão de Plaquetas/efeitos adversos , Púrpura Trombocitopênica Trombótica/etiologia , Púrpura Trombocitopênica Trombótica/imunologia , Sistema de Registros , Trombocitopenia/etiologia , Trombose/etiologia
15.
Front Immunol ; 12: 627986, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093522

RESUMO

Seropositive rheumatoid arthritis (RA) is characterized by the presence of rheumatoid factor (RF) and anti-citrullinated protein autoantibodies (ACPA) with different fine-specificities. Yet, other serum anti-modified protein autoantibodies (AMPA), e.g. anti-carbamylated (Carb), -acetylated (KAc), and malondialdehyde acetaldehyde (MAA) modified protein antibodies, have been described. In this comprehensive study, we analyze 30 different IgG and IgA AMPA reactivities to Cit, Carb, KAc, and MAA antigens detected by ELISA and autoantigen arrays in N=1985 newly diagnosed RA patients. Association with patient characteristics such as smoking and disease activity were explored. Carb and KAc reactivities by different assays were primarily seen in patients also positive for anti-citrulline reactivity. Modified vimentin (mod-Vim) peptides were used for direct comparison of different AMPA reactivities, revealing that IgA AMPA recognizing mod-Vim was mainly detected in subsets of patients with high IgG anti-Cit-Vim levels and a history of smoking. IgG reactivity to acetylation was mainly detected in a subset of patients with Cit and Carb reactivity. Anti-acetylated histone reactivity was RA-specific and associated with high anti-CCP2 IgG levels, multiple ACPA fine-specificities, and smoking status. This reactivity was also found to be present in CCP2+ RA-risk individuals without arthritis. Our data further demonstrate that IgG autoreactivity to MAA was increased in RA compared to controls with highest levels in CCP2+ RA, but was not RA-specific, and showed low correlation with other AMPA. Anti-MAA was instead associated with disease activity and was not significantly increased in CCP2+ individuals at risk of RA. Notably, RA patients could be subdivided into four different subsets based on their AMPA IgG and IgA reactivity profiles. Our serology results were complemented by screening of monoclonal antibodies derived from single B cells from RA patients for the same antigens as the RA cohort. Certain CCP2+ clones had Carb or Carb+KAc+ multireactivity, while such reactivities were not found in CCP2- clones. We conclude that autoantibodies exhibiting different patterns of ACPA fine-specificities as well as Carb and KAc reactivity are present in RA and may be derived from multireactive B-cell clones. Carb and KAc could be considered reactivities within the "Cit-umbrella" similar to ACPA fine-specificities, while MAA reactivity is distinctly different.


Assuntos
Artrite Reumatoide/imunologia , Autoanticorpos/sangue , Autoantígenos/imunologia , Autoimunidade , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Processamento de Proteína Pós-Traducional , Acetilação , Adulto , Idoso , Anticorpos Anti-Proteína Citrulinada/sangue , Especificidade de Anticorpos , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Malondialdeído/imunologia , Pessoa de Meia-Idade , Peptídeos Cíclicos/imunologia , Carbamilação de Proteínas
18.
Transfusion ; 61(7): 2169-2178, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34181769

RESUMO

BACKGROUND: Despite the significant adverse clinical consequences of RBC alloimmunization, our understanding of the signals that induce immune responses to transfused RBCs remains incomplete. Though RBC storage has been shown to enhance alloimmunization in the hen egg lysozyme, ovalbumin, and human Duffy (HOD) RBC alloantigen mouse model, the molecular signals leading to immune activation in this system remain unclear. Given that the nonclassical major histocompatibility complex (MHC) Class I molecule CD1D can bind to multiple different lysophospholipids and direct immune activation, we hypothesized that storage of RBCs increases lysophospholipids known to bind CD1D, and further that recipient CD1D recognition of these altered lipids mediates storage-induced alloimmunization responses. STUDY DESIGN AND METHODS: We used a mass spectrometry-based approach to analyze the changes in lysophospholipids that are induced during storage of mouse RBCs. CD1D knockout (CD1D-KO) and wild-type (WT) control mice were transfused with stored HOD RBCs to measure the impact of CD1D deficiency on RBC alloimmunization. RESULTS: RBC storage results in alterations in multiple lysophospholipid species known to bind to CD1D and activate the immune system. Prior to transfusion, CD1D-deficient mice had lower baseline levels of polyclonal immunoglobulin (IgG) relative to WT mice. In response to stored RBC transfusion, CD1D-deficient mice generated similar levels of anti-HOD IgM and anti-HOD IgG. CONCLUSION: Although storage of RBCs leads to alteration of several lysophospholipids known to be capable of binding CD1D, storage-induced RBC alloimmunization responses are not impacted by recipient CD1D deficiency.


Assuntos
Antígenos CD1d/imunologia , Preservação de Sangue , Transfusão de Sangue , Eritrócitos/imunologia , Isoanticorpos/biossíntese , Isoantígenos/imunologia , Lisofosfolipídeos/sangue , Reação Transfusional/imunologia , Alarminas/sangue , Alarminas/imunologia , Animais , Especificidade de Anticorpos , Antígenos CD1d/genética , Antígenos CD1d/metabolismo , Sistema do Grupo Sanguíneo Duffy/genética , Sistema do Grupo Sanguíneo Duffy/imunologia , Feminino , Imunização , Imunoglobulina G/biossíntese , Imunoglobulina G/imunologia , Imunoglobulina M/biossíntese , Imunoglobulina M/imunologia , Isoanticorpos/imunologia , Lisofosfolipídeos/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Camundongos Transgênicos , Muramidase/imunologia , Ovalbumina/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia
19.
Viruses ; 13(5)2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067226

RESUMO

The bluetongue virus (BTV) is transmitted by Culicoides biting midges and causes bluetongue (BT), an OIE-notifiable disease of ruminants. At least 29 BTV serotypes are described as determined by the outer shell proteins VP2 and VP5. Vaccination is the most effective control measure. Inactivated and live-attenuated vaccines (LAVs) are currently available. These vaccines have their specific pros and cons, and both are not DIVA vaccines. The BT Disabled Infectious Single Animal (DISA) vaccine platform is based on LAV without nonessential NS3/NS3a expression and is applicable for many serotypes by the exchange of outer shell proteins. The DISA vaccine is effective and completely safe. Further, transmission of the DISA vaccine by midges is blocked (DISA principle). Finally, the DISA vaccine enables DIVA because of a lack of antibodies against the immunogenic NS3/NS3a protein (DIVA principle). The deletion of 72 amino acids (72aa) in NS3/NS3a is sufficient to block virus propagation in midges. Here, we show that a prototype DISA vaccine based on LAV with the 72aa deletion enables DIVA, is completely safe and induces a long-lasting serotype-specific protection in cattle. In conclusion, the in-frame deletion of 72-aa codons in the BT DISA/DIVA vaccine platform is sufficient to fulfil all the criteria for modern veterinary vaccines.


Assuntos
Vírus Bluetongue/genética , Vírus Bluetongue/imunologia , Doenças dos Bovinos/prevenção & controle , Vacinas Atenuadas/imunologia , Proteínas não Estruturais Virais/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Bluetongue/prevenção & controle , Bluetongue/virologia , Bovinos , Genoma Viral , Imunização , Sorogrupo , Vacinas Virais/administração & dosagem , Vacinas Virais/efeitos adversos
20.
Toxins (Basel) ; 13(6)2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071768

RESUMO

This study aimed to detect and monitor total Zearalenone (ZEN) and its five homologs (ZENs) in cereals and feed. The monoclonal antibodies (mAbs) with a high affinity and broad class specificity against ZENs were prepared, and the conditions of a heterologous indirect competitive ELISA (icELISA) were preliminarily optimized based on the ZEN mAbs. The immunogen ZEN-BSA was synthesized using the oxime active ester method (OAE) and identified using infrared (IR) and ultraviolet (UV). The coating antigen ZEN-OVA was obtained via the 1,4-butanediol diglycidyl ether method (BDE). Balb/c mice were immunized using a high ZEN-BSA dose with long intervals and at multiple sites. A heterologous indirect non-competitive ELISA (inELISA) and an icELISA were used to screen the suitable cell fusion mice and positive hybridoma cell lines. The ZEN mAbs were prepared by inducing ascites in vivo. The standard curve was established, and the sensitivity and specificity of the ZEN mAbs were determined under the optimized icELISA conditions. ZEN-BSA was successfully synthesized at a conjugation ratio of 17.2:1 (ZEN: BSA). Three hybridoma cell lines, 2D7, 3C2, and 4A10, were filtered, and their mAbs corresponded to an IgG1 isotype with a κ light chain. The mAbs titers were between (2.56 to 5.12) × 102 in supernatants and (1.28 to 5.12) × 105 in the ascites. Besides, the 50% inhibitive concentration (IC50) values were from 18.65 to 31.92 µg/L in the supernatants and 18.12 to 31.46 µg/L in the ascites. The affinity constant (Ka) of all of the mAbs was between 4.15 × 109 and 6.54 × 109 L/mol. The IC50 values of mAb 2D7 for ZEN, α-ZEL, ß-ZEL, α-ZAL, ß-ZAL and ZAN were 17.23, 16.71, 18.27, 16.39, 20.36 and 15.01 µg/L, and their cross-reactivities (CRs, %) were 100%, 103.11%, 94.31%, 105.13%, 84.63%, and 114.79%, respectively, under the optimized icELISA conditions. The limit of detection (LOD) for ZEN was 0.64 µg/L, and its linear working range was between 1.03 and 288.55 µg/L. The mAbs preparation and the optimization of icELISA conditions promote the potential development of a rapid test ELISA kit, providing an alternative method for detecting ZEN and its homologs in cereals and feed.


Assuntos
Anticorpos Monoclonais/biossíntese , Afinidade de Anticorpos , Especificidade de Anticorpos , Zearalenona/imunologia , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Soroalbumina Bovina/imunologia , Zearalenona/análise , Zearalenona/metabolismo
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