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1.
Mol Syst Biol ; 17(9): e10243, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34487431

RESUMO

Systems serology provides a broad view of humoral immunity by profiling both the antigen-binding and Fc properties of antibodies. These studies contain structured biophysical profiling across disease-relevant antigen targets, alongside additional measurements made for single antigens or in an antigen-generic manner. Identifying patterns in these measurements helps guide vaccine and therapeutic antibody development, improve our understanding of diseases, and discover conserved regulatory mechanisms. Here, we report that coupled matrix-tensor factorization (CMTF) can reduce these data into consistent patterns by recognizing the intrinsic structure of these data. We use measurements from two previous studies of HIV- and SARS-CoV-2-infected subjects as examples. CMTF outperforms standard methods like principal components analysis in the extent of data reduction while maintaining equivalent prediction of immune functional responses and disease status. Under CMTF, model interpretation improves through effective data reduction, separation of the Fc and antigen-binding effects, and recognition of consistent patterns across individual measurements. Data reduction also helps make prediction models more replicable. Therefore, we propose that CMTF is an effective general strategy for data exploration in systems serology.


Assuntos
Sorodiagnóstico da AIDS , Teste Sorológico para COVID-19 , COVID-19/imunologia , Interpretação Estatística de Dados , Infecções por HIV/imunologia , Sorodiagnóstico da AIDS/métodos , Sorodiagnóstico da AIDS/estatística & dados numéricos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/metabolismo , Teste Sorológico para COVID-19/métodos , Teste Sorológico para COVID-19/estatística & dados numéricos , Humanos , Imunidade Humoral , Células Matadoras Naturais/imunologia , Modelos Logísticos , Receptores Fc/imunologia , Receptores de IgG/imunologia
2.
Cell Rep ; 37(1): 109798, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34587481

RESUMO

Despite the worldwide effect of the coronavirus disease 2019 (COVID-19) pandemic, the underlying mechanisms of fatal viral pneumonia remain elusive. Here, we show that critical COVID-19 is associated with enhanced eosinophil-mediated inflammation when compared to non-critical cases. In addition, we confirm increased T helper (Th)2-biased adaptive immune responses, accompanying overt complement activation, in the critical group. Moreover, enhanced antibody responses and complement activation are associated with disease pathogenesis as evidenced by formation of immune complexes and membrane attack complexes in airways and vasculature of lung biopsies from six fatal cases, as well as by enhanced hallmark gene set signatures of Fcγ receptor (FcγR) signaling and complement activation in myeloid cells of respiratory specimens from critical COVID-19 patients. These results suggest that SARS-CoV-2 infection may drive specific innate immune responses, including eosinophil-mediated inflammation, and subsequent pulmonary pathogenesis via enhanced Th2-biased immune responses, which might be crucial drivers of critical disease in COVID-19 patients.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , Proteínas do Sistema Complemento/imunologia , Eosinófilos/imunologia , Inflamação/imunologia , Pneumonia Viral/imunologia , SARS-CoV-2/imunologia , Imunidade Adaptativa , Adulto , Idoso , Idoso de 80 Anos ou mais , Complexo Antígeno-Anticorpo/metabolismo , COVID-19/metabolismo , COVID-19/virologia , Ativação do Complemento , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Eosinófilos/virologia , Feminino , Humanos , Inflamação/metabolismo , Inflamação/virologia , Lesão Pulmonar/imunologia , Lesão Pulmonar/patologia , Lesão Pulmonar/virologia , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/metabolismo , Receptores de IgG/imunologia , Receptores de IgG/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais , Células Th2/imunologia , Carga Viral , Adulto Jovem
3.
J Infect Dis ; 224(4): 575-585, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34398243

RESUMO

Severe coronavirus disease 2019 (COVID-19) is associated with an overactive inflammatory response mediated by macrophages. Here, we analyzed the phenotype and function of neutrophils in patients with COVID-19. We found that neutrophils from patients with severe COVID-19 express high levels of CD11b and CD66b, spontaneously produce CXCL8 and CCL2, and show a strong association with platelets. Production of CXCL8 correlated with plasma concentrations of lactate dehydrogenase and D-dimer. Whole blood assays revealed that neutrophils from patients with severe COVID-19 show a clear association with immunoglobulin G (IgG) immune complexes. Moreover, we found that sera from patients with severe disease contain high levels of immune complexes and activate neutrophils through a mechanism partially dependent on FcγRII (CD32). Interestingly, when integrated in immune complexes, anti-severe acute respiratory syndrome coronavirus 2 IgG antibodies from patients with severe COVID-19 displayed a higher proinflammatory profile compared with antibodies from patients with mild disease. Our study suggests that IgG immune complexes might promote the acquisition of an inflammatory signature by neutrophils, worsening the course of COVID-19.


Assuntos
Anticorpos Antivirais/imunologia , Complexo Antígeno-Anticorpo/imunologia , COVID-19/imunologia , Imunoglobulina G/imunologia , Ativação de Neutrófilo/imunologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Complexo Antígeno-Anticorpo/sangue , Antígenos CD/imunologia , Antígeno CD11b/imunologia , Moléculas de Adesão Celular/imunologia , Feminino , Proteínas Ligadas por GPI/imunologia , Humanos , Imunoglobulina G/sangue , Interleucina-8/imunologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Receptores de IgG/imunologia , SARS-CoV-2/imunologia , Adulto Jovem
4.
Nat Commun ; 12(1): 4791, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373452

RESUMO

Classical dendritic cells (cDC) are professional antigen-presenting cells (APC) that regulate immunity and tolerance. Neutrophil-derived cells with properties of DCs (nAPC) are observed in human diseases and after culture of neutrophils with cytokines. Here we show that FcγR-mediated endocytosis of antibody-antigen complexes or an anti-FcγRIIIB-antigen conjugate converts neutrophils into nAPCs that, in contrast to those generated with cytokines alone, activate T cells to levels observed with cDCs and elicit CD8+ T cell-dependent anti-tumor immunity in mice. Single cell transcript analyses and validation studies implicate the transcription factor PU.1 in neutrophil to nAPC conversion. In humans, blood nAPC frequency in lupus patients correlates with disease. Moreover, anti-FcγRIIIB-antigen conjugate treatment induces nAPCs that can activate autologous T cells when using neutrophils from individuals with myeloid neoplasms that harbor neoantigens or those vaccinated against bacterial toxins. Thus, anti-FcγRIIIB-antigen conjugate-induced conversion of neutrophils to immunogenic nAPCs may represent a possible immunotherapy for cancer and infectious diseases.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias/imunologia , Neutrófilos/imunologia , Receptores de IgG/genética , Receptores de IgG/imunologia , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Apresentação do Antígeno/imunologia , Complexo Antígeno-Anticorpo , Medula Óssea , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Movimento Celular , Proliferação de Células , Citocinas/imunologia , Células Dendríticas/imunologia , Endocitose , Humanos , Imunidade Inata , Imunoterapia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Espécies Reativas de Oxigênio , Transcriptoma
5.
PLoS Negl Trop Dis ; 15(7): e0009508, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34237073

RESUMO

The complement system is activated in tuberculous pleural effusion (TPE), with increased levels of the anaphylatoxins stimulating pleural mesothelial cells (PMCs) to secrete chemokines, which recruit nonclassical monocytes to the pleural cavity. The differentiation and recruitment of naive CD4+ T cells are induced by pleural cytokines and PMC-produced chemokines in TPE. However, it is unclear whether anaphylatoxins orchestrate CD4+ T cell response via interactions between PMCs and monocytes in TPE. In this study, CD16+ and CD16- monocytes isolated from TPE patients were cocultured with PMCs pretreated with anaphylatoxins. After removing the PMCs, the conditioned monocytes were cocultured with CD4+ T cells. The levels of the cytokines were measured in PMCs and monocyte subsets treated separately with anaphylatoxins. The costimulatory molecules were assessed in conditioned monocyte subsets. Furthermore, CD4+ T cell response was evaluated in different coculture systems. The results indicated that anaphylatoxins induced PMCs and CD16+ monocytes to secrete abundant cytokines capable of only inducing Th17 expansion, but Th1 was feeble. In addition, costimulatory molecules were more highly expressed in CD16+ than in CD16- monocytes isolated from TPE. The interactions between monocytes and PMCs enhanced the ability of PMCs and monocytes to produce cytokines and that of monocytes to express HLA-DR, CD40, CD80 and CD86, which synergistically induced Th17 expansion. In the above process, anaphylatoxins enhanced the interactions between monocytes and PMCs by increasing the level of the cytokines IL-1ß, IL-6, IL-23 and upregulating the phenotype of CD40 and CD80 in CD16+ monocytes. Collectively, these data indicate that anaphylatoxins play a central role in orchestrating Th17 response mainly via interactions between CD16+ monocytes and PMCs in TPE.


Assuntos
Anafilatoxinas/imunologia , Epitélio/imunologia , Monócitos/imunologia , Derrame Pleural/imunologia , Células Th17/imunologia , Tuberculose/imunologia , Adulto , Linfócitos T CD4-Positivos , Citocinas/imunologia , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Epitélio/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/fisiologia , Derrame Pleural/microbiologia , Receptores de IgG/imunologia , Tuberculose/microbiologia
6.
Nature ; 596(7873): 565-569, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34233346

RESUMO

Vaccine-induced immune thrombotic thrombocytopaenia (VITT) is a rare adverse effect of COVID-19 adenoviral vector vaccines1-3. VITT resembles heparin-induced thrombocytopaenia (HIT) in that it is associated with platelet-activating antibodies against platelet factor 4 (PF4)4; however, patients with VITT develop thrombocytopaenia and thrombosis without exposure to heparin. Here we sought to determine the binding site on PF4 of antibodies from patients with VITT. Using alanine-scanning mutagenesis5, we found that the binding of anti-PF4 antibodies from patients with VITT (n = 5) was restricted to eight surface amino acids on PF4, all of which were located within the heparin-binding site, and that the binding was inhibited by heparin. By contrast, antibodies from patients with HIT (n = 10) bound to amino acids that corresponded to two different sites on PF4. Biolayer interferometry experiments also revealed that VITT anti-PF4 antibodies had a stronger binding response to PF4 and PF4-heparin complexes than did HIT anti-PF4 antibodies, albeit with similar dissociation rates. Our data indicate that VITT antibodies can mimic the effect of heparin by binding to a similar site on PF4; this allows PF4 tetramers to cluster and form immune complexes, which in turn causes Fcγ receptor IIa (FcγRIIa; also known as CD32a)-dependent platelet activation. These results provide an explanation for VITT-antibody-induced platelet activation that could contribute to thrombosis.


Assuntos
Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/imunologia , Epitopos de Linfócito B/imunologia , Trombocitopenia/induzido quimicamente , Trombocitopenia/imunologia , Trombose/induzido quimicamente , Trombose/imunologia , Adulto , Idoso , Sequência de Aminoácidos , Anticorpos/imunologia , Sítios de Ligação de Anticorpos , Feminino , Heparina/química , Heparina/imunologia , Heparina/metabolismo , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Ativação Plaquetária , Fator Plaquetário 4/imunologia , Receptores de IgG/imunologia
7.
Viruses ; 13(6)2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072720

RESUMO

Identification of therapeutics against emerging and re-emerging viruses remains a continued priority that is only reinforced by the recent SARS-CoV-2 pandemic. Advances in monoclonal antibody (mAb) isolation, characterization, and production make it a viable option for rapid treatment development. While mAbs are traditionally screened and selected based on potency of neutralization in vitro, it is clear that additional factors contribute to the in vivo efficacy of a mAb beyond viral neutralization. These factors include interactions with Fc receptors (FcRs) and complement that can enhance neutralization, clearance of infected cells, opsonization of virions, and modulation of the innate and adaptive immune response. In this review, we discuss recent studies, primarily using mouse models, that identified a role for Fc-FcγR interactions for optimal antibody-based protection against emerging and re-emerging virus infections.


Assuntos
Doenças Transmissíveis Emergentes/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Receptores de IgG/imunologia , Viroses/imunologia , Vírus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/uso terapêutico , Citotoxicidade Celular Dependente de Anticorpos , Doenças Transmissíveis Emergentes/terapia , Doenças Transmissíveis Emergentes/virologia , Humanos , Imunização Passiva , Fagocitose , Viroses/terapia , Viroses/virologia , Vírus/classificação
8.
FASEB J ; 35(7): e21746, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34151465

RESUMO

Bullous pemphigoid (BP), an autoimmune skin disease, is characterized by autoantibodies against hemidesmosomal proteins in the skin and mucous membranes. Neutrophils infiltrate BP skin lesions, however, their role in immune dysregulation remains unclear. We investigated whether BP involves aberrant neutrophil extracellular traps (NETs) formation in skin lesions and circulation; and examined the triggers and deleterious immuno-inflammatory consequences. In the present study, we found that circulating NET-related biomarker levels increased in serum and blister fluid of BP patients and significantly correlated with disease severity. Additionally, circulating neutrophils from BP patients displayed enhanced spontaneous NETs formation than healthy controls. In vitro, BP180-NC16A immune complexes-induced NETosis in neutrophils from BP patients, which was abrogated by Fcγ receptor and/or NADPH pathway blockade. Furthermore, the elevated levels of NETs from BP patients boosted autoantibody production by inducing B-cell differentiation into plasma cells, mediated by MAPK P38 cascade activation. Together, our findings provide strong evidence that NETs are involved in a pathogenic loop, causing excessive differentiation of B cells and promotion of autoantibody production. Hence, targeting aberrant neutrophil responses will provide novel potential targets for the treatment of BP.


Assuntos
Formação de Anticorpos/imunologia , Linfócitos B/imunologia , Diferenciação Celular/imunologia , Armadilhas Extracelulares/imunologia , Neutrófilos/imunologia , Penfigoide Bolhoso/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Linfócitos B/metabolismo , Biomarcadores/metabolismo , Vesícula/imunologia , Vesícula/metabolismo , Armadilhas Extracelulares/metabolismo , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Neutrófilos/metabolismo , Penfigoide Bolhoso/metabolismo , Plasmócitos/imunologia , Plasmócitos/metabolismo , Receptores de IgG/imunologia , Transdução de Sinais/imunologia , Pele/imunologia , Pele/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
Science ; 372(6546): 1102-1105, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34083490

RESUMO

Although antiviral antibodies generally confer protective functions, antibodies against dengue virus (DENV) are associated with enhanced disease susceptibility. Antibodies can mediate DENV infection of leukocytes via Fcγ receptors, likely contributing to dengue disease pathogenesis. To determine if this mechanism accounts for variable disease severity, we examined Fab and Fc structures of anti-DENV antibodies from patients before and after infection and with variable disease outcomes. Neither antibody titers nor neutralizing activity correlated with disease severity in DENV-infected populations. Rather, DENV infection induced a specific increase in immunoglobulin G1 (IgG1) afucosylation, and the levels of afucosylated IgG1 were predictive of dengue disease severity. Thus, the IgG1 fucosylation status represents a robust prognostic tool for dengue disease, highlighting the key role of the Fc glycan structure in dengue pathogenesis.


Assuntos
Anticorpos Antivirais/sangue , Anticorpos Antivirais/química , Vírus da Dengue/imunologia , Dengue/imunologia , Fucose/análise , Dengue Grave/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores , Criança , Coinfecção/imunologia , Dengue/fisiopatologia , Feminino , Humanos , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/química , Imunoglobulina G/imunologia , Masculino , Receptores de IgG/química , Receptores de IgG/imunologia , Dengue Grave/fisiopatologia , Índice de Gravidade de Doença , Infecção por Zika virus/imunologia
10.
Blood ; 137(26): 3656-3659, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33945605

RESUMO

Vaccination is crucial in combatting the severe acute respiratory syndrome coronavirus 2 pandemic. The rare complication of thrombocytopenia and thrombotic complications at unusual sites after ChAdOx1 nCov-19 vaccination is caused by platelet-activating antibodies directed against platelet factor 4 (PF4). We present a widely applicable whole-blood standard flow cytometric assay to identify the pathogenic antibodies associated with vaccine-induced immune-mediated thrombotic thrombocytopenia (VITT) after ChAdOx1 nCov-19 vaccination. This assay will enable rapid diagnosis by many laboratories. This trial was registered at www.clinicaltrials.gov as #NCT04370119.


Assuntos
Autoanticorpos/sangue , Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Citometria de Fluxo/métodos , Imunoglobulina G/sangue , Ativação Plaquetária/imunologia , Fator Plaquetário 4/imunologia , Púrpura Trombocitopênica Idiopática/diagnóstico , Receptores de IgG/imunologia , SARS-CoV-2 , Vacinação/efeitos adversos , Especificidade de Anticorpos , Autoanticorpos/biossíntese , Autoanticorpos/imunologia , Vacinas contra COVID-19/imunologia , Heparina/efeitos adversos , Heparina/imunologia , Humanos , Técnicas Imunoenzimáticas , Imunogenicidade da Vacina , Imunoglobulina G/biossíntese , Imunoglobulina G/imunologia , Selectina-P/análise , Púrpura Trombocitopênica Idiopática/etiologia , Púrpura Trombocitopênica Idiopática/imunologia
11.
J Immunol ; 206(11): 2638-2651, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34031148

RESUMO

HIV reservoirs persist in gut-homing CD4+ T cells of people living with HIV and receiving antiretroviral therapy, but the antigenic specificity of such reservoirs remains poorly documented. The imprinting for gut homing is mediated by retinoic acid (RA), a vitamin A-derived metabolite produced by dendritic cells (DCs) exhibiting RA-synthesizing (RALDH) activity. RALDH activity in DCs can be induced by TLR2 ligands, such as bacterial peptidoglycans and fungal zymosan. Thus, we hypothesized that bacterial/fungal pathogens triggering RALDH activity in DCs fuel HIV reservoir establishment/outgrowth in pathogen-reactive CD4+ T cells. Our results demonstrate that DCs derived from intermediate/nonclassical CD16+ compared with classical CD16- monocytes exhibited superior RALDH activity and higher capacity to transmit HIV infection to autologous Staphylococcus aureus-reactive T cells. Exposure of total monocyte-derived DCs (MDDCs) to S. aureus lysates as well as TLR2 (zymosan and heat-killed preparation of Listeria monocytogenes) and TLR4 (LPS) agonists but not CMV lysates resulted in a robust upregulation of RALDH activity. MDDCs loaded with S. aureus or zymosan induced the proliferation of T cells with a CCR5+integrin ß7+CCR6+ phenotype and efficiently transmitted HIV infection to these T cells via RALDH/RA-dependent mechanisms. Finally, S. aureus- and zymosan-reactive CD4+ T cells of antiretroviral therapy-treated people living with HIV carried replication-competent integrated HIV-DNA, as demonstrated by an MDDC-based viral outgrowth assay. Together, these results support a model in which bacterial/fungal pathogens in the gut promote RALDH activity in MDDCs, especially in CD16+ MDDCs, and subsequently imprint CD4+ T cells with gut-homing potential and HIV permissiveness. Thus, nonviral pathogens play key roles in fueling HIV reservoir establishment/outgrowth via RALDH/RA-dependent mechanisms that may be therapeutically targeted.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Infecções por HIV/imunologia , Monócitos/imunologia , Receptores de IgG/imunologia , Tretinoína/imunologia , Adulto , Feminino , Fungos/imunologia , Proteínas Ligadas por GPI/imunologia , Humanos , Listeria monocytogenes/imunologia , Masculino , Pessoa de Meia-Idade , Staphylococcus aureus/imunologia , Adulto Jovem
12.
Front Immunol ; 12: 640672, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017328

RESUMO

The differentiation of human induced pluripotent stem cells (hiPSCs) into T and natural killer (NK) lymphocytes opens novel possibilities for developmental studies of immune cells and in-vitro generation of cell therapy products. In particular, iPSC-derived NK cells gained interest in adoptive anti-cancer immunotherapies, since they enable generation of homogenous populations of NK cells with and without genetic engineering that can be grown at clinical scale. However, the phenotype of in-vitro generated NK cells is not well characterized. NK cells derive in the bone marrow and mature in secondary lymphoid tissues through distinct stages from CD56brightCD16- to CD56dimCD16+ NK cells that represents the most abandoned population in peripheral blood. In this study, we efficiently generated CD56+CD16+CD3- NK lymphocytes from hiPSC and characterized NK-cell development by surface expression of NK-lineage markers. Hematopoietic priming of hiPSC resulted in 31.9% to 57.4% CD34+CD45+ hematopoietic progenitor cells (HPC) that did not require enrichment for NK lymphocyte propagation. HPC were further differentiated into NK cells on OP9-DL1 feeder cells resulting in high purity of CD56brightCD16- and CD56brightCD16+ NK cells. The output of generated NK cells increased up to 40% when OP9-DL1 feeder cells were inactivated with mitomycine C. CD7 expression could be detected from the first week of differentiation indicating priming towards the lymphoid lineage. CD56brightCD16-/+ NK cells expressed high levels of DNAM-1, CD69, natural killer cell receptors NKG2A and NKG2D, and natural cytotoxicity receptors NKp46, NKp44, NKp30. Expression of NKp80 on 40% of NK cells, and a perforin+ and granzyme B+ phenotype confirmed differentiation up to stage 4b. Killer cell immunoglobulin-like receptor KIR2DL2/DL3 and KIR3DL1 were found on up to 3 and 10% of mature NK cells, respectively. NK cells were functional in terms of cytotoxicity, degranulation and antibody-dependent cell-mediated cytotoxicity.


Assuntos
Diferenciação Celular/imunologia , Células Matadoras Naturais/imunologia , Subpopulações de Linfócitos/metabolismo , Antígeno CD56/imunologia , Técnicas de Cultura de Células/métodos , Degranulação Celular/imunologia , Proteínas Ligadas por GPI/imunologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/imunologia , Células Matadoras Naturais/citologia , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos/citologia , Receptores de IgG/imunologia , Receptores KIR2DL2/imunologia , Receptores KIR2DL3/imunologia , Receptores KIR3DL1/imunologia
13.
Immunology ; 164(2): 348-357, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34037988

RESUMO

Granulocytes mediate broad immunoprotection through phagocytosis, extracellular traps, release of cytotoxic granules, antibody effector functions and recruitment of other immune cells against pathogens. However, descriptions of granulocytes in HIV infection and mucosal tissues are limited. Our goal was to characterize granulocyte subsets in systemic, mucosal and lymphoid tissues during lentiviral infection using the rhesus macaque (RM) model. Mononuclear cells from jejunum, colon, cervix, vagina, lymph nodes, spleen, liver and whole blood from experimentally naïve and chronically SHIVsf162p3-infected RM were analysed by microscopy and polychromatic flow cytometry. Granulocytes were identified using phenotypes designed specifically for RM: eosinophils-CD45+  CD66+  CD49d+ ; neutrophils-CD45+  CD66+  CD14+ ; and basophils-CD45+  CD123+  FcRε+ . Nuclear visualization with DAPI staining and surface marker images by ImageStream (cytometry/microscopy) further confirmed granulocytic phenotypes. Flow cytometric data showed that all RM granulocytes expressed CD32 (FcRγII) but did not express CD16 (FcRγIII). Additionally, constitutive expression of CD64 (FcRγI) on neutrophils and FcRε on basophils indicates the differential expression of Fc receptors on granulocyte subsets. Granulocytic subsets in naïve whole blood ranged from 25·4% to 81·5% neutrophils, 0·59% to 13·3% eosinophils and 0·059% to 1·8% basophils. Interestingly, elevated frequencies of circulating neutrophils, colorectal neutrophils and colorectal eosinophils were all observed in chronic lentiviral disease. Conversely, circulating basophils, jejunal eosinophils, vaginal neutrophils and vaginal eosinophils of SHIVsf162p3-infected RM declined in frequency. Overall, our data suggest modulation of granulocytes in chronic lentiviral infection, most notably in the gastrointestinal mucosae where a significant inflammation and disruption occurs in lentivirus-induced disease. Furthermore, granulocytes may migrate to inflamed tissues during infection and could serve as targets of immunotherapeutic intervention.


Assuntos
Granulócitos/imunologia , Infecções por Lentivirus/imunologia , Macaca mulatta/imunologia , Membrana Mucosa/imunologia , Animais , Basófilos/imunologia , Basófilos/virologia , Eosinófilos/imunologia , Eosinófilos/virologia , Citometria de Fluxo/métodos , Granulócitos/virologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Contagem de Leucócitos/métodos , Membrana Mucosa/virologia , Neutrófilos/imunologia , Neutrófilos/virologia , Receptores de IgG/imunologia
14.
Front Immunol ; 12: 625030, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34046030

RESUMO

Human immunodeficiency virus type 1 (HIV-1) infection remains a major public health threat due to its incurable nature and the lack of a highly efficacious vaccine. The RV144 vaccine trial is the only clinical study to date that demonstrated significant but modest decrease in HIV infection risk. To improve HIV-1 vaccine immunogenicity and efficacy, we recently evaluated pox-protein vaccination using a next generation liposome-based adjuvant, Army Liposomal Formulation adsorbed to aluminum (ALFA), in rhesus monkeys and observed 90% efficacy against limiting dose mucosal SHIV challenge in male animals. Here, we analyzed binding antibody responses, as assessed by Fc array profiling using a broad range of HIV-1 envelope antigens and Fc features, to explore the mechanisms of ALFA-mediated protection by employing machine learning and Cox proportional hazards regression analyses. We found that Fcγ receptor 2a-related binding antibody responses were augmented by ALFA relative to aluminium hydroxide, and these responses were associated with reduced risk of infection in male animals. Our results highlight the application of systems serology to provide mechanistic insights to vaccine-elicited protection and support evidence that antibody effector responses protect against HIV-1 infection.


Assuntos
Vacinas contra a AIDS/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Imunogenicidade da Vacina , Vacinas contra a SAIDS/administração & dosagem , Síndrome de Imunodeficiência Adquirida dos Símios/prevenção & controle , Vírus da Imunodeficiência Símia/imunologia , Vacinas contra a AIDS/imunologia , Animais , Feminino , Anticorpos Anti-HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Macaca mulatta , Masculino , Receptores de IgG/imunologia , Vacinas contra a SAIDS/imunologia , Fatores Sexuais , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vacinação
15.
Front Immunol ; 12: 641521, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33796107

RESUMO

One mechanism by which monoclonal antibodies (mAb) help treat cancer or autoimmune disease is through triggering antibody-dependent cellular cytotoxicity (ADCC) via CD16 on Natural Killer (NK) cells. Afucosylation is known to increase the affinity of mAbs for CD16 on NK cells and here, we set out to assess how mAb afucosylation affects the dynamics of NK cell interactions, receptor expression and effector functions. An IgG1 version of a clinically important anti-CD20 mAb was compared to its afucosylated counterpart (anti-CD20-AF). Opsonization of CD20-expressing target cells, 721.221 or Daudi, with anti-CD20-AF increased NK cell cytotoxicity and IFNγ secretion, compared to anti-CD20. The afucosylated mAb also caused a more rapid and greater loss of CD16 from NK cell surfaces. Loss of CD16 has recently been shown to be important for NK cell detachment and sequential engagement of multiple target cells. Here, live-cell time-lapse microscopy of individual cell-cell interactions in an aqueous environment and a three-dimensional matrix, revealed that anti-CD20-AF induced more rapid killing of opsonized target cells. In addition, NK cells detached more quickly from target cells opsonized with anti-CD20-AF compared to anti-CD20, which increased engagement of multiple targets and enabled a greater proportion of NK cells to perform serial killing. Inhibition of CD16 shedding with TAPI-0 led to reduced detachment and serial killing. Thus, disassembly of the immune synapse caused by loss of cell surface CD16 is a factor determining the efficiency of ADCC and antibody afucosylation alters the dynamics of intercellular interactions to boost serial killing.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Células Matadoras Naturais/imunologia , Receptores de IgG/imunologia , Antígenos CD20/imunologia , Fucose , Proteínas Ligadas por GPI/imunologia , Humanos , Imunoglobulina G , Sinapses Imunológicas/imunologia
16.
Nat Commun ; 12(1): 2037, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795692

RESUMO

The hallmarks of COVID-19 are higher pathogenicity and mortality in the elderly compared to children. Examining baseline SARS-CoV-2 cross-reactive immunological responses, induced by circulating human coronaviruses (hCoVs), is needed to understand such divergent clinical outcomes. Here we show analysis of coronavirus antibody responses of pre-pandemic healthy children (n = 89), adults (n = 98), elderly (n = 57), and COVID-19 patients (n = 50) by systems serology. Moderate levels of cross-reactive, but non-neutralizing, SARS-CoV-2 antibodies are detected in pre-pandemic healthy individuals. SARS-CoV-2 antigen-specific Fcγ receptor binding accurately distinguishes COVID-19 patients from healthy individuals, suggesting that SARS-CoV-2 infection induces qualitative changes to antibody Fc, enhancing Fcγ receptor engagement. Higher cross-reactive SARS-CoV-2 IgA and IgG are observed in healthy elderly, while healthy children display elevated SARS-CoV-2 IgM, suggesting that children have fewer hCoV exposures, resulting in less-experienced but more polyreactive humoral immunity. Age-dependent analysis of COVID-19 patients, confirms elevated class-switched antibodies in elderly, while children have stronger Fc responses which we demonstrate are functionally different. These insights will inform COVID-19 vaccination strategies, improved serological diagnostics and therapeutics.


Assuntos
Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Criança , Pré-Escolar , Reações Cruzadas/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Pessoa de Meia-Idade , Receptores de IgG/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
17.
J Virol ; 95(13): e0021921, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-33853957

RESUMO

No prophylactic vaccine has provided robust protection against human immunodeficiency virus type 1 (HIV-1). Vaccine-induced broadly neutralizing antibodies (bNAbs) have not been achieved in humans and most animals; however, cows vaccinated with HIV-1 envelope trimers produce bNAbs with unusually long third heavy complementarity-determining regions (CDRH3s). Alongside neutralization, Fc-mediated effector functions, including antibody-dependent cellular cytotoxicity (ADCC) and phagocytosis (ADP), may be critical for in vivo bNAb antiviral activity. Here, we aimed to augment the Fc-dependent effector functions of a chimeric human-bovine bNAb, NC-Cow1, which binds the CD4 binding site (CD4bs) and exhibits broader and more potent neutralization than most human CD4bs bNAbs by using an exceptionally long 60-amino acid (aa) CDRH3. The bovine variable region of NC-Cow1 was paired with a human IgG1 Fc region mutated to create the following three variants: G236R/L328R (GRLR) that abrogates Fc-gamma receptor (FcγR) binding, and two variants that enhance binding, namely, G236A/S239D/I332E (GASDIE) and G236A/S239D/A330L/I332E (GASDALIE). Both GASDIE and GASDALIE improved binding to human FcγRIIA and FcγRIIIA, enhanced human natural killer (NK) cell activation, and mediated higher levels of ADCC and ADP activity than the wild-type human IgG1 Fc. GASDALIE mediated higher phagocytic activity than GASDIE. As expected, GRLR eliminated binding to FcγRs and did not mediate ADCC or ADP. We demonstrated that mutations in the human Fc region of bovine chimeric antibodies with ultralong CDRH3s could enhance antibody effector functions while maintaining envelope binding and neutralization. This study will have significant implications in the development of multifunctional anti-HIV antibodies, which may be important to prevent HIV-1 transmission in an antibody-based topical microbicide. IMPORTANCE Despite successful antiviral chemotherapy, human immunodeficiency virus (HIV) is still a lifelong persistent virus, and no vaccine yet prevents HIV transmission. Topical microbicides offer an important alternative method to prevent sexual transmission of HIV-1. With the production of highly potent anti-HIV-1 broadly neutralizing antibodies (bNAbs) and multifunctional antibodies, monoclonal antibodies are now important prophylactic agents. Recently discovered anti-HIV-1 bovine bNAbs (with higher potency and breadth than most human bNAbs) could be novel candidates as potent topical microbicides. Our study is significant as it demonstrates the compatibility of combining bovine-derived neutralization with human-derived antibody-effector functions. This study is a new approach to antibody engineering that strengthens the feasibility of using high-potency bovine variable region bNAbs with augmented Fc function and promotes them as a strong candidate for antibody-mediated therapies.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Anticorpos Amplamente Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/prevenção & controle , Proteínas Recombinantes de Fusão/imunologia , Animais , Bovinos , Linhagem Celular , Infecções por HIV/transmissão , HIV-1/imunologia , Humanos , Imunoglobulina G/imunologia , Células Matadoras Naturais/imunologia , Fagocitose/imunologia , Engenharia de Proteínas , Receptores de IgG/imunologia
18.
Theranostics ; 11(11): 5430-5446, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859756

RESUMO

Human immunoglobulin G (IgG), especially autoantibodies, has major implications for the diagnosis and management of a wide range of autoimmune diseases. However, some healthy individuals also have autoantibodies, while a portion of patients with autoimmune diseases test negative for serologic autoantibodies. Recent advances in glycomics have shown that IgG Fc N-glycosylations are more reliable diagnostic and monitoring biomarkers than total IgG autoantibodies in a wide variety of autoimmune diseases. Furthermore, these N-glycosylations of IgG Fc, particularly sialylation, have been reported to exert significant anti-inflammatory effects by upregulating inhibitory FcγRIIb on effector macrophages and reducing the affinity of IgG for either complement protein or activating Fc gamma receptors. Therefore, sialylated IgG is a potential therapeutic strategy for attenuating pathogenic autoimmunity. IgG sialylation-based therapies for autoimmune diseases generated through genetic, metabolic or chemoenzymatic modifications have made some advances in both preclinical studies and clinical trials.


Assuntos
Doenças Autoimunes/imunologia , Imunoglobulina G/imunologia , Animais , Autoanticorpos/imunologia , Humanos , Fragmentos Fc das Imunoglobulinas/imunologia , Macrófagos/imunologia , Receptores de IgG/imunologia , Regulação para Cima/imunologia
19.
Theranostics ; 11(12): 6033-6043, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33897897

RESUMO

Immune checkpoint blockade therapies, especially those targeting the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) have achieved impressive clinical responses in multiple types of cancers. To optimize the therapeutic effect of the checkpoint antibodies, many strategies including targeting delivery, controlled release, and cellular synthesis have been developed. However, within these strategies, antibodies were attached to drug carriers by chemical bonding, which may affect the steric configuration and function of the antibodies. Herein, we prepared cluster of differentiation 64 (CD64), a natural catcher of the fragment crystalline (Fc) of monomeric immunoglobulin G (IgG), and over-expressed it on the cell membrane nanovesicles (NVs) as PD-L1 antibody delivery vehicle (CD64-NVs-aPD-L1), which was employed to disrupt the PD-1/PD-L1 immunosuppressive signal axis for boosting T cell dependent tumor elimination. Meanwhile, chemical immunomodulatory drug cyclophosphamide (CP) was also encapsulated in the vesicle (CD64-NVs-aPD-L1-CP), to simultaneously restrain the regulatory T cells (Tregs) and invigorate Ki67+CD8+ T cells, then further enhance their anti-tumor ability. Methods: The cell membrane NVs overexpressing CD64 were incubated with PD-L1 antibody and chemotherapeutic agent CP to prepare CD64-NVs-aPD-L1-CP. Results: The CD64-NVs-aPD-L1-CP could simultaneously interrupt the immunosuppressive effect of PD-L1 and decrease the inhibition of Tregs, leading to tumor growth suppression and survival time extension. Conclusion: CD64-NVs are charismatic carriers to achieve both checkpoint blockade and immunomodulatory drugs for combined cancer immunotherapy.


Assuntos
Anticorpos/imunologia , Portadores de Fármacos/química , Neoplasias/imunologia , Neoplasias/terapia , Receptores de IgG/imunologia , Receptores de IgG/metabolismo , Animais , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Ciclofosfamida/farmacologia , Engenharia Genética/métodos , Células HEK293 , Humanos , Inibidores de Checkpoint Imunológico/imunologia , Imunoglobulina G/metabolismo , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos C57BL
20.
Nat Commun ; 12(1): 1742, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33741975

RESUMO

A highly protective vaccine will greatly facilitate achieving and sustaining malaria elimination. Understanding mechanisms of antibody-mediated immunity is crucial for developing vaccines with high efficacy. Here, we identify key roles in humoral immunity for Fcγ-receptor (FcγR) interactions and opsonic phagocytosis of sporozoites. We identify a major role for neutrophils in mediating phagocytic clearance of sporozoites in peripheral blood, whereas monocytes contribute a minor role. Antibodies also promote natural killer cell activity. Mechanistically, antibody interactions with FcγRIII appear essential, with FcγRIIa also required for maximum activity. All regions of the circumsporozoite protein are targets of functional antibodies against sporozoites, and N-terminal antibodies have more activity in some assays. Functional antibodies are slowly acquired following natural exposure to malaria, being present among some exposed adults, but uncommon among children. Our findings reveal targets and mechanisms of immunity that could be exploited in vaccine design to maximize efficacy.


Assuntos
Imunidade Humoral , Malária/imunologia , Malária/prevenção & controle , Receptores de IgG/imunologia , Esporozoítos/imunologia , Adulto , Idoso , Anticorpos Antiprotozoários/imunologia , Criança , Feminino , Humanos , Quênia , Vacinas Antimaláricas/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Neutrófilos/imunologia , Fagocitose/imunologia , Plasmodium falciparum/imunologia , Receptores de IgG/metabolismo , Células THP-1 , Adulto Jovem
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