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2.
Proc Natl Acad Sci U S A ; 121(23): e2309674121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38722806

RESUMO

The identification of immunogenic peptides has become essential in an increasing number of fields in immunology, ranging from tumor immunotherapy to vaccine development. The nature of the adaptive immune response is shaped by the similarity between foreign and self-protein sequences, a concept extensively applied in numerous studies. Can we precisely define the degree of similarity to self? Furthermore, do we accurately define immune self? In the current work, we aim to unravel the conceptual and mechanistic vagueness hindering the assessment of self-similarity. Accordingly, we demonstrate the remarkably low consistency among commonly employed measures and highlight potential avenues for future research.


Assuntos
Peptídeos , Humanos , Peptídeos/imunologia , Peptídeos/química , Imunidade Adaptativa/imunologia , Imunoterapia/métodos , Autoantígenos/imunologia , Animais
3.
Int J Mol Sci ; 25(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38673811

RESUMO

Despite conventional therapy, lupus nephritis (LN) remains a significant contributor to short- and long-term morbidity and mortality. B cell abnormalities and the production of autoantibodies against nuclear complexes like anti-dsDNA are recognised as key players in the pathogenesis of LN. To address the challenges of chronic immunosuppression associated with current therapies, we have engineered T cells to express chimeric autoantibody receptors (DNA-CAART) for the precise targeting of B cells expressing anti-dsDNA autoantibodies. T cells from LN patients were transduced using six different CAAR vectors based on their antigen specificity, including alpha-actinin, histone-1, heparan sulphate, or C1q. The cytotoxicity, cytokine production, and cell-cell contact of DNA-CAART were thoroughly investigated in co-culture experiments with B cells isolated from patients, both with and without anti-dsDNA positivity. The therapeutic effects were further evaluated using an in vitro immune kidney LN organoid. Among the six proposed DNA-CAART, DNA4 and DNA6 demonstrated superior selectively cytotoxic activity against anti-dsDNA+ B cells. Notably, DNA4-CAART exhibited improvements in organoid morphology, apoptosis, and the inflammatory process in the presence of IFNα-stimulated anti-dsDNA+ B cells. Based on these findings, DNA4-CAART emerge as promising candidates for modulating autoimmunity and represent a novel approach for the treatment of LN.


Assuntos
Autoantígenos , Linfócitos B , Nefrite Lúpica , Linfócitos T , Humanos , Nefrite Lúpica/imunologia , Nefrite Lúpica/terapia , Nefrite Lúpica/patologia , Linfócitos B/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Autoantígenos/imunologia , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Receptores de Antígenos Quiméricos/genética , Feminino , Anticorpos Antinucleares/imunologia , Autoanticorpos/imunologia , Adulto , Masculino , Citocinas/metabolismo
4.
J Neuroimmunol ; 390: 578343, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38615370

RESUMO

Since the 1980s it is known that immune responses to the Epstein-Barr virus (EBV) are elevated in multiple sclerosis (MS) patients. Recent seroepidemiologial data have shown that this alteration after primary EBV infection identifies individuals with a more than 30-fold increased risk to develop MS. The mechanisms by which EBV infection might erode tolerance for the central nervous system (CNS) in these individuals, years prior to clinical MS onset, remain unclear. In this review I will discuss altered frequencies of EBV life cycle stages and their tissue distribution, EBV with CNS autoantigen cross-reactive immune responses and loss of immune control for autoreactive B and T cells as possible mechanisms. This discussion is intended to stimulate future studies into these mechanisms with the aim to identify candidates for interventions that might correct EBV specific immune control and/or resulting cross-reactivities with CNS autoantigens in MS patients and thereby ameliorate disease activity.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Esclerose Múltipla , Humanos , Esclerose Múltipla/imunologia , Esclerose Múltipla/virologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/imunologia , Animais , Autoantígenos/imunologia
5.
J Neuroimmunol ; 390: 578347, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38663308

RESUMO

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system resulting from loss of immune tolerance. Many disease-modifying therapies for MS have broad immunosuppressive effects on peripheral immune cells, but this can increase risks of infection and attenuate vaccine-elicited immunity. A more targeted approach is to re-establish immune tolerance in an autoantigen-specific manner. This review discusses methods to achieve this, focusing on tolerogenic dendritic cells. Clinical trials in other autoimmune diseases also provide learnings with regards to clinical translation of this approach, including identification of autoantigen(s), selection of appropriate patients and administration route and frequency.


Assuntos
Células Dendríticas , Tolerância Imunológica , Imunoterapia , Esclerose Múltipla , Humanos , Células Dendríticas/imunologia , Células Dendríticas/transplante , Esclerose Múltipla/imunologia , Esclerose Múltipla/terapia , Animais , Tolerância Imunológica/imunologia , Imunoterapia/métodos , Autoantígenos/imunologia
6.
Immunogenetics ; 76(3): 175-187, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38607388

RESUMO

One of the probable hypotheses for the onset of autoimmunity is molecular mimicry. This study aimed to determine the HLA-II risk alleles for developing Hashimoto's thyroiditis (HT) in order to analyze the molecular homology between candidate pathogen-derived epitopes and potentially self-antigens (thyroid peroxidase, TPO) based on the presence of HLA risk alleles. HLA-DRB1/-DQB1 genotyping was performed in 100 HT patients and 330 ethnically matched healthy controls to determine the predisposing/protective alleles for HT disease. Then, in silico analysis was conducted to examine the sequence homology between epitopes derived from autoantigens and four potentially relevant pathogens and their binding capacities to HLA risk alleles based on peptide docking analysis. We identified HLA-DRB1*03:01, *04:02, *04:05, and *11:04 as predisposing alleles and DRB1*13:01 as a potentially predictive allele for HT disease. Also, DRB1*11:04 ~ DQB1*03:01 (Pc = 0.002; OR, 3.97) and DRB1*03:01 ~ DQB1*02:01 (Pc = 0.004; OR, 2.24) haplotypes conferred a predisposing role for HT. Based on logistic regression analysis, carrying risk alleles increased the risk of HT development 4.5 times in our population (P = 7.09E-10). Also, ROC curve analysis revealed a high predictive power of those risk alleles for discrimination of the susceptible from healthy individuals (AUC, 0.70; P = 6.6E-10). Analysis of peptide sequence homology between epitopes of TPO and epitopes derived from four candidate microorganisms revealed a homology between envelop glycoprotein D of herpes virus and sequence 151-199 of TPO with remarkable binding capacity to HLA-DRB1*03:01 allele. Our findings indicate the increased risk of developing HT in those individuals carrying HLA risk alleles which can also be related to herpes virus infection.


Assuntos
Alelos , Autoantígenos , Epitopos , Predisposição Genética para Doença , Cadeias beta de HLA-DQ , Cadeias HLA-DRB1 , Doença de Hashimoto , Humanos , Masculino , Feminino , Doença de Hashimoto/genética , Doença de Hashimoto/imunologia , Adulto , Irã (Geográfico) , Cadeias HLA-DRB1/genética , Cadeias beta de HLA-DQ/genética , Autoantígenos/imunologia , Autoantígenos/genética , Epitopos/imunologia , Epitopos/genética , Pessoa de Meia-Idade , Estudos de Casos e Controles , Iodeto Peroxidase/genética , Iodeto Peroxidase/imunologia , Haplótipos , Genótipo , Frequência do Gene
7.
Front Immunol ; 15: 1329013, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38665908

RESUMO

Introduction: Subgroups of autoantibodies directed against voltage-gated potassium channel (Kv) complex components have been associated with immunotherapy-responsive clinical syndromes. The high prevalence and the role of autoantibodies directly binding Kv remain, however, controversial. Our objective was to determine Kv autoantibody binding requirements and to clarify their contribution to the observed immune response. Methods: Binding epitopes were studied in sera (n = 36) and cerebrospinal fluid (CSF) (n = 12) from a patient cohort positive for Kv1.2 but negative for 32 common neurological autoantigens and controls (sera n = 18 and CSF n = 5) by phospho and deep mutational scans. Autoantibody specificity and contribution to the observed immune response were resolved on recombinant cells, cerebellum slices, and nerve fibers. Results: 83% of the patients (30/36) within the studied cohort shared one out of the two major binding epitopes with Kv1.2-3 reactivity. Eleven percent (4/36) of the serum samples showed no binding. Fingerprinting resolved close to identical sequence requirements for both shared epitopes. Kv autoantibody response is directed against juxtaparanodal regions in peripheral nerves and the axon initial segment in central nervous system neurons and exclusively mediated by the shared epitopes. Discussion: Systematic mapping revealed two shared autoimmune responses, with one dominant Kv1.2-3 autoantibody epitope being unexpectedly prevalent. The conservation of the molecular binding requirements among these patients indicates a uniform autoantibody repertoire with monospecific reactivity. The enhanced sensitivity of the epitope-based (10/12) compared with that of the cell-based detection (7/12) highlights its use for detection. The determined immunodominant epitope is also the primary immune response visible in tissue, suggesting a diagnostic significance and a specific value for routine screening.


Assuntos
Autoanticorpos , Autoimunidade , Epitopos Imunodominantes , Canal de Potássio Kv1.2 , Humanos , Autoanticorpos/imunologia , Autoanticorpos/sangue , Canal de Potássio Kv1.2/imunologia , Epitopos Imunodominantes/imunologia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Autoantígenos/imunologia , Mapeamento de Epitopos , Animais
8.
Rev Alerg Mex ; 71(1): 54, 2024 Feb 01.
Artigo em Espanhol | MEDLINE | ID: mdl-38683072

RESUMO

OBJECTIVE: Analyze the molecular mimicry between Plasmodium spp. and autoantigens associated with GBS, identifying possible antigenic epitopes. METHODS: PSI-Blast, Praline, Emboss, Protein Data Bank, Swiss Model Server, AlphaFold 2, Ellipro and PyMol 2.3 were used to search for homologies, perform alignments, obtain protein structures, and predict epitopes. RESULTS: 17 autoantigens and seven immunological targets of the peripheral nervous system were included, identifying 72 possible epitopes associated with GBS. From the proteome of Plasmodium spp. (298 proteins), only two showed similarities close to 30% with TRIM21 and BACE1, generating seven possible epitopes. CONCLUSION: No significant homologies were observed between the proteome of GBS and Plasmodium spp. The exploration of other mechanisms such as immune-mediated capillary damage, Epitope Spreading or Bystander Activation is suggested to explain the mentioned association. These findings underscore the need to clarify the etiology of autoimmune diseases and the role of pathogens. The need for experimental studies to validate these results is emphasized.


OBJETIVO: Analizar el mimetismo molecular entre Plasmodium spp. y autoantígenos asociados al SGB, identificando posibles epítopos antigénicos. MÉTODOS: Se emplearon PSI-Blast, Praline, Emboss, Protein Data Bank, Swiss Model Server, AlphaFold 2, Ellipro y PyMol 2.3 para buscar homologías, realizar alineamientos, obtener estructuras proteicas y predecir epítopos. RESULTADOS: Se incluyeron 17 autoantígenos y siete objetivos inmunológicos del sistema nervioso periférico, identificándose 72 posibles epítopos asociados al SGB. Del proteoma de Plasmodium spp. (298 proteínas), solo dos mostraron similitud cercana al 30% con TRIM21 y BACE1, generando siete posibles epítopos. CONCLUSIÓN: No se observaron homologías significativas entre el proteoma de SGB y Plasmodium spp. Se sugiere la exploración de otros mecanismos como el daño capilar inmunomediado, Epitope Spreading o Bystander Activation para explicar la asociación mencionada. Estos hallazgos subrayan la necesidad de aclarar la etiología de las enfermedades autoinmunes y el papel de los patógenos. Se enfatiza la necesidad de estudios experimentales para validar estos resultados.


Assuntos
Síndrome de Guillain-Barré , Mimetismo Molecular , Mimetismo Molecular/imunologia , Síndrome de Guillain-Barré/imunologia , Humanos , Plasmodium/imunologia , Autoantígenos/imunologia , Epitopos/imunologia
9.
Rev Alerg Mex ; 71(1): 61, 2024 Feb 01.
Artigo em Espanhol | MEDLINE | ID: mdl-38683079

RESUMO

INTRODUCTION: Cardiovascular diseases are the result of genetic and environmental interaction that conditions the integrity of the heart and blood vessels. Risk factors include infections. The inflammatory response against the infectious agent is a trigger of autoimmune cardiovascular diseases due to the similarity between the pathogen proteins and human antigens, since the immune response can present cross-reactivity caused by molecular mimicry. METHODS: We performed a search for pathogens involved in autoimmune heart diseases and autoantigens 9 associated with these diseases in the Pubmed and Google Scholar search engines. Identity between proteins was performed through global alignments using PSI-BLAST. The 3D structures of the proteins were obtained by Uniprot or NCBI and, if not found, the structure was modeled by homology using the Swiss Model server. Epitope prediction was performed through Ellipro and the Immunological Epitope Database (IEDB). In addition, the PYMOL program was used to visualize proteins in 3D and position the epitopes in the structure. RESULTS: A total of ten cardiovascular proteins showed identity (30-88,24%) in their amino acid sequences with antigens from 10 pathogens. Actin proteins and heat shock protein (HSP) families had higher levels of identity with Trypanosoma Cruzi, Cryptococcus neoformans, and Chlamydia trachomatis, 71,47%, 88,24%, and 80,61%, respectively. Other pathogens, such as Streptococcus pyogenes, Bacillus sp, Magnetospirillum gryphiswaldense, Helicobacter pylori and Chlamydia pneumoniae, presented a moderate identity with a maximum value of 65,79%. CONCLUSION: Human actin and HSPs share a high degree of conservation with epitopes from various microorganisms, such as bacteria, fungi and protozoa, suggesting molecular mimicry and cross-reactivity as a mechanism for the development of atherosclerosis, heart disease rheumatic disease, myocarditis and Chagas heart disease. In vitro and in vivo work is needed to demonstrate the results obtained in the In Silico analysis.


INTRODUCCIÓN: Las enfermedades cardiovasculares son el resultado de la interacción genética y ambiental que condiciona la integridad del corazón y los vasos sanguíneos. Los factores de riesgo incluyen infecciones. La respuesta inflamatoria contra el agente infeccioso es un desencadenante de las enfermedades cardiovasculares autoinmunes, debido a la similitud entre las proteínas del patógeno y los antígenos humanos, pues la respuesta inmunitaria puede presentar reactividad cruzada causada por mimetismo molecular. MÉTODOS: Realizamos una búsqueda de patógenos involucrados en enfermedades cardíacas autoinmunes y de autoantígenos asociados a estas enfermedades en los buscadores Pubmed y Google Scholar. La identidad entre proteínas se realizó a través de alineamientos globales utilizando PSI-BLAST. Las estructuras 3D de las proteínas fue obtenida por Uniprot o NCBI y, si no se encontraban, las estructuras se modelaban por homología, utilizando el servidor Swiss Model. La predicción de los epítopes se realizó a través de Ellipro, y la Base de Datos de Epítopos Inmunológicos (IEDB). Además, se utilizó el programa PYMOL para la visualización de proteínas en 3D, y el posicionamiento de los epítopes en la estructura. RESULTADOS: Diez proteínas cardiovasculares mostraron una identidad (30-88,24%) en sus secuencias de aminoácidos con antígenos de diez patógenos. Las proteínas de actina y las familias de proteínas de choque térmico (HSP, por sus siglas en inglés), presentaron niveles de identidad más altos con Trypanosoma Cruzi, Cryptococcus neoformans y Chlamydia trachomatis, 71,47%, 88,24% y 80,61%, respectivamente. Otros patógenos, como Streptococcus pyogenes, Bacillus sp, Magnetospirillum gryphiswaldense, Helicobacter pylori y Chlamydia pneumoniae, presentaron identidad moderada con un valor máximo del 65,79%. CONCLUSIÓN: La actina humana y las HSP comparten un alto grado de conservación con epítopos de varios microorganismos, como bacterias, hongos y protozoos; lo que sugiere la imitación molecular y la reactividad cruzada como mecanismos para el desarrollo de la aterosclerosis, la enfermedad cardíaca reumática, la miocarditis y la enfermedad cardíaca de Chagas. Se necesitan trabajos in vitro e in vivo, que demuestren los resultados obtenidos en el análisis In Silico.


Assuntos
Doenças Cardiovasculares , Mimetismo Molecular , Humanos , Mimetismo Molecular/imunologia , Antígenos de Bactérias/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia
10.
Sci Rep ; 14(1): 9571, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671086

RESUMO

Primary vitreoretinal lymphoma (PVRL) is a rare subtype of DLBCL and can progress into primary central nervous system lymphoma (PCNSL). To investigate the role of chronic antigenic stimulation in PVRL, we cloned and expressed B-cell receptors (BCR) from PVRL patients and tested for binding against human auto-antigens. SEL1L3, a protein with multiple glycosylation sites, was identified as the BCR target in 3/20 PVRL cases. SEL1L3 induces proliferation and BCR pathway activation in aggressive lymphoma cell lines. Moreover, SEL1L3 conjugated to a toxin killed exclusively lymphoma cells with respective BCR-reactivity. Western Blot analysis indicates the occurrence of hyper-N-glycosylation of SEL1L3 at aa 527 in PVRL patients with SEL1L3-reactive BCRs. The BCR of a PVRL patient with serum antibodies against SEL1L3 was cloned from a vitreous body biopsy at diagnosis and of a systemic manifestation at relapse. VH4-04*07 was used in both lymphoma manifestations with highly conserved CDR3 regions. Both BCRs showed binding to SEL1L3, suggesting continued dependence of lymphoma cells on antigen stimulation. These results indicate an important role of antigenic stimulation by post-translationally modified auto-antigens in the genesis of PVRL. They also provide the basis for a new treatment approach targeting unique lymphoma BCRs with ultimate specificity.


Assuntos
Receptores de Antígenos de Linfócitos B , Humanos , Receptores de Antígenos de Linfócitos B/metabolismo , Glicosilação , Linhagem Celular Tumoral , Neoplasias da Retina/genética , Neoplasias da Retina/metabolismo , Neoplasias da Retina/patologia , Neoplasias da Retina/imunologia , Autoantígenos/imunologia , Autoantígenos/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/metabolismo , Feminino , Masculino , Corpo Vítreo/metabolismo , Corpo Vítreo/patologia , Pessoa de Meia-Idade , Idoso
11.
Bull Math Biol ; 86(6): 66, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38678489

RESUMO

The development of autoimmune diseases often takes years before clinical symptoms become detectable. We propose a mathematical model for the immune response during the initial stage of Systemic Lupus Erythematosus which models the process of aberrant apoptosis and activation of macrophages and neutrophils. NETosis is a type of cell death characterised by the release of neutrophil extracellular traps, or NETs, containing material from the neutrophil's nucleus, in response to a pathogenic stimulus. This process is hypothesised to contribute to the development of autoimmunogenicity in SLE. The aim of this work is to study how NETosis contributes to the establishment of persistent autoantigen production by analysing the steady states and the asymptotic dynamics of the model by numerical experiment.


Assuntos
Apoptose , Armadilhas Extracelulares , Lúpus Eritematoso Sistêmico , Conceitos Matemáticos , Modelos Imunológicos , Neutrófilos , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Humanos , Neutrófilos/imunologia , Apoptose/imunologia , Autoantígenos/imunologia , Simulação por Computador , Macrófagos/imunologia , Macrófagos/metabolismo , Ativação de Neutrófilo/imunologia , Ativação de Macrófagos
12.
J Dermatol Sci ; 114(1): 44-51, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508975

RESUMO

BACKGROUND: Bullous pemphigoid (BP) is an antibody-mediated blistering disease predominantly affecting the elderly. The pathogenesis involves both complement-dependent and complement-independent mechanisms. The therapeutic potential of targeting complement-independent mechanism has not yet been determined. The mainstay of treatment, corticosteroid, has many side effects, indicating the needs of better treatments. OBJECTIVE: We tempted to establish an in vitro model of BP which resembles complement-independent mechanism and to examine the therapeutic potential of a novel anti-inflammatory agent, diacerein. METHODS: Cultured HaCaT cells were treated with purified antibodies from BP patients, with or without diacerein to measure the cell interface presence of BP180, protein kinase C, and the production of proinflammatory cytokines. An open-label, randomized, phase 2 trial was conducted to compare topical diacerein and clobetasol ointments in patients with mild-to-moderate BP (NCT03286582). RESULTS: The reduced presentation of BP180 at cell interface after treating with BP autoantibodies was noticed in immunofluorescence and western blotting studies. The phenomenon was restored by diacerein. Diacerein also reduced the autoantibody-induced increase of pro-inflammatory cytokines. Reciprocal changes of BP180 and protein kinase C at the cell interface were found after treating with BP autoantibodies. This phenomenon was also reversed by diacerein in a dose-dependent manner. The phase 2 trial showed that topical diacerein reduced the clinical symptoms which were comparable to those of topical clobetasol. CONCLUSION: Diacerein inhibited BP autoantibody-induced reduction of BP180 and production of proinflammatory cytokines in vitro and showed therapeutic potential in patients with BP. It is a novel drug worthy of further investigations.


Assuntos
Antraquinonas , Autoanticorpos , Citocinas , Colágenos não Fibrilares , Penfigoide Bolhoso , Humanos , Penfigoide Bolhoso/imunologia , Penfigoide Bolhoso/tratamento farmacológico , Penfigoide Bolhoso/patologia , Antraquinonas/farmacologia , Antraquinonas/uso terapêutico , Autoanticorpos/imunologia , Autoanticorpos/sangue , Colágenos não Fibrilares/imunologia , Citocinas/metabolismo , Citocinas/imunologia , Colágeno Tipo XVII , Autoantígenos/imunologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Clobetasol/uso terapêutico , Clobetasol/farmacologia , Idoso , Masculino , Células HaCaT , Feminino , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Proteína Quinase C/imunologia , Proteínas do Sistema Complemento/imunologia , Linhagem Celular , Resultado do Tratamento , Queratinócitos/imunologia , Queratinócitos/efeitos dos fármacos
13.
J Autoimmun ; 145: 103196, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38458075

RESUMO

Type 1 diabetes (T1D) results from a breakdown in immunological tolerance, with pivotal involvement of antigen-presenting cells. In this context, antigen-specific immunotherapies have been developed to arrest autoimmunity, such as phosphatidylserine (PS)-liposomes. However, the role of certain antigen-presenting cells in immunotherapy, particularly human macrophages (Mφ) in T1D remains elusive. The aim of this study was to determine the role of Mφ in antigen-specific immune tolerance and T1D. To that end, we evaluated Mφ ability to capture apoptotic-body mimicking PS-liposomes in mice and conducted a phenotypic and functional characterisation of four human monocyte-derived Mφ (MoMφ) subpopulations (M0, M1, M2a and M2c) after PS-liposomes uptake. Our findings in mice identified Mφ as the most phagocytic cell subset in the spleen and liver. In humans, while phagocytosis rates were comparable between T1D and control individuals, PS-liposome capture dynamics differed among Mφ subtypes, favouring inflammatory (M1) and deactivated (M2c) Mφ. Notably, high nanoparticle concentrations did not affect macrophage viability. PS-liposome uptake by Mφ induced alterations in membrane molecule expression related to immunoregulation, reduced secretion of IL-6 and IL-12, and diminished autologous T-cell proliferation in the context of autoantigen stimulation. These results underscore the tolerogenic effects of PS-liposomes and emphasize their potential to target human Mφ, providing valuable insights into the mechanism of action of this preclinical immunotherapy.


Assuntos
Autoantígenos , Diabetes Mellitus Tipo 1 , Imunoterapia , Lipossomos , Macrófagos , Fosfatidilserinas , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/imunologia , Animais , Humanos , Fosfatidilserinas/metabolismo , Fosfatidilserinas/imunologia , Camundongos , Imunoterapia/métodos , Macrófagos/imunologia , Macrófagos/metabolismo , Autoantígenos/imunologia , Feminino , Tolerância Imunológica , Fagocitose/imunologia , Masculino , Camundongos Endogâmicos NOD , Autoimunidade , Adulto
14.
Nature ; 627(8003): 407-415, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38383779

RESUMO

Neuromyelitis optica is a paradigmatic autoimmune disease of the central nervous system, in which the water-channel protein AQP4 is the target antigen1. The immunopathology in neuromyelitis optica is largely driven by autoantibodies to AQP42. However, the T cell response that is required for the generation of these anti-AQP4 antibodies is not well understood. Here we show that B cells endogenously express AQP4 in response to activation with anti-CD40 and IL-21 and are able to present their endogenous AQP4 to T cells with an AQP4-specific T cell receptor (TCR). A population of thymic B cells emulates a CD40-stimulated B cell transcriptome, including AQP4 (in mice and humans), and efficiently purges the thymic TCR repertoire of AQP4-reactive clones. Genetic ablation of Aqp4 in B cells rescues AQP4-specific TCRs despite sufficient expression of AQP4 in medullary thymic epithelial cells, and B-cell-conditional AQP4-deficient mice are fully competent to raise AQP4-specific antibodies in productive germinal-centre responses. Thus, the negative selection of AQP4-specific thymocytes is dependent on the expression and presentation of AQP4 by thymic B cells. As AQP4 is expressed in B cells in a CD40-dependent (but not AIRE-dependent) manner, we propose that thymic B cells might tolerize against a group of germinal-centre-associated antigens, including disease-relevant autoantigens such as AQP4.


Assuntos
Aquaporina 4 , Autoanticorpos , Autoantígenos , Linfócitos B , Tolerância Imunológica , Neuromielite Óptica , Animais , Humanos , Camundongos , Proteína AIRE , Aquaporina 4/deficiência , Aquaporina 4/genética , Aquaporina 4/imunologia , Aquaporina 4/metabolismo , Autoanticorpos/imunologia , Autoantígenos/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Antígenos CD40/imunologia , Centro Germinativo/citologia , Centro Germinativo/imunologia , Neuromielite Óptica/imunologia , Neuromielite Óptica/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Timo/citologia , Timo/imunologia , Células Epiteliais da Tireoide/imunologia , Células Epiteliais da Tireoide/metabolismo , Transcriptoma
15.
Immunol Cell Biol ; 102(5): 353-357, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38216149

RESUMO

Immunology research holds significant potential for enhanced inclusivity at the beginning of the science literacy journey, but persistent challenges stem from limited awareness that improvement is needed in this field. At the 2023 Monash Sensory Science Exhibition, we had the opportunity to present several tactile posters, using simple materials, for visually impaired participants to showcase our research on the pathogenesis of rheumatoid arthritis as a result of immune tolerance breakdown and liposome-based tolerogenic immunotherapy. The posters stimulated lively discussions about autoimmune arthritic diseases and our research. With consideration of the diversity of the participants, the efforts of scientists in promoting science literacy for the community can promote a more inclusive environment and engage and inspire a broader audience.


Assuntos
Artrite Reumatoide , Calcitriol , Tolerância Imunológica , Imunoterapia , Lipossomos , Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Humanos , Imunoterapia/métodos , Calcitriol/administração & dosagem , Peptídeos/administração & dosagem , Peptídeos/imunologia , Animais , Autoantígenos/imunologia
16.
Adv Healthc Mater ; 13(12): e2304238, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38295848

RESUMO

There is no curative treatment for chronic auto-inflammatory diseases including rheumatoid arthritis, and current treatments can induce off-target side effects due to systemic immune suppression. This work has previously shown that dexamethasone-pulsed tolerogenic dendritic cells loaded with the arthritis-specific antigen human proteoglycan can suppress arthritis development in a proteoglycan-induced arthritis mouse model. To circumvent ex vivo dendritic cell culture, and enhance antigen-specific effects, drug delivery vehicles, such as liposomes, provide an interesting approach. Here, this work uses anionic 1,2-distearoyl-sn-glycero-3-phosphoglycerol liposomes with enhanced loading of human proteoglycan-dexamethasone conjugates by cationic lysine tetramer addition. Antigen-pulsed tolerogenic dendritic cells induced by liposomal dexamethasone in vitro enhanced antigen-specific regulatory T cells to a similar extent as dexamethasone-induced tolerogenic dendritic cells. In an inflammatory adoptive transfer model, mice injected with antigen-dexamethasone liposomes have significantly higher antigen-specific type 1 regulatory T cells than mice injected with antigen only. The liposomes significantly inhibit the progression of arthritis compared to controls in preventative and therapeutic proteoglycan-induced arthritis mouse models. This coincides with systemic tolerance induction and an increase in IL10 expression in the paws of mice. In conclusion, a single administration of autoantigen and dexamethasone-loaded liposomes seems to be a promising antigen-specific treatment strategy for arthritis in mice.


Assuntos
Autoantígenos , Células Dendríticas , Dexametasona , Lipossomos , Animais , Lipossomos/química , Dexametasona/química , Dexametasona/farmacologia , Camundongos , Autoantígenos/imunologia , Autoantígenos/química , Células Dendríticas/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Humanos , Artrite Experimental/imunologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/terapia , Proteoglicanas/química , Proteoglicanas/farmacologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Artrite Reumatoide/imunologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/terapia , Artrite Reumatoide/induzido quimicamente
18.
Acta Pharmacol Sin ; 45(4): 674-685, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38097717

RESUMO

Autoimmune diseases (AIDs) arise from a breakdown in immunological self-tolerance, wherein the adaptive immune system mistakenly attacks healthy cells, tissues and organs. AIDs impose excessive treatment costs and currently rely on non-specific and universal immunosuppression, which only offer symptomatic relief without addressing the underlying causes. AIDs are driven by autoantigens, targeting the autoantigens holds great promise in transforming the treatment of these diseases. To achieve this goal, a comprehensive understanding of the pathogenic mechanisms underlying different AIDs and the identification of specific autoantigens are critical. In this review, we categorize AIDs based on their underlying causes and compile information on autoantigens implicated in each disease, providing a roadmap for the development of novel immunotherapy regimens. We will focus on type 1 diabetes (T1D), which is an autoimmune disease characterized by irreversible destruction of insulin-producing ß cells in the Langerhans islets of the pancreas. We will discuss insulin as possible autoantigen of T1D and its role in T1D pathogenesis. Finally, we will review current treatments of TID and propose a potentially effective immunotherapy targeting autoantigens.


Assuntos
Autoantígenos , Doenças Autoimunes , Diabetes Mellitus Tipo 1 , Descoberta de Drogas , Insulina , Humanos , Autoantígenos/imunologia , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Insulina/imunologia
19.
Autoimmun Rev ; 23(3): 103508, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38160960

RESUMO

The complicated relationships between autoimmunity, COVID-19, and COVID-19 vaccinations are described, giving insight into their intricacies. Antinuclear antibodies (ANA), anti-Ro/SSA, rheumatoid factor, lupus anticoagulant, and antibodies against interferon (IFN)-I have all been consistently found in COVID-19 patients, indicating a high prevalence of autoimmune reactions following viral exposure. Furthermore, the discovery of human proteins with structural similarities to SARS-CoV-2 peptides as possible autoantigens highlights the complex interplay between the virus and the immune system in initiating autoimmunity. An updated summary of the current status of COVID-19 vaccines is presented. We present probable pathways underpinning the genesis of COVID-19 autoimmunity, such as bystander activation caused by hyperinflammatory conditions, viral persistence, and the creation of neutrophil extracellular traps. These pathways provide important insights into the development of autoimmune-related symptoms ranging from organ-specific to systemic autoimmune and inflammatory illnesses, demonstrating the wide influence of COVID-19 on the immune system.


Assuntos
Autoimunidade , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Vacinas contra COVID-19/imunologia , Autoimunidade/imunologia , Doenças Autoimunes/imunologia , Autoantígenos/imunologia
20.
Int J Mol Sci ; 24(13)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37446157

RESUMO

Atherosclerotic cardiovascular disease is the most common cause of morbidity and death worldwide. Recent studies have demonstrated that this chronic inflammatory disease of the arterial wall can be controlled through the modulation of immune system activity. Many patients with cardiovascular disease remain at elevated risk of recurrent events despite receiving current, state-of-the-art preventive medical treatment. Much of this residual risk is attributed to inflammation. Therefore, finding new treatment strategies for this category of patients became of common interest. This review will discuss the experimental and clinical data supporting the possibility of developing immune-based therapies for lowering cardiovascular risk, explicitly focusing on vaccination strategies.


Assuntos
Aterosclerose , Imunomodulação , Humanos , Aterosclerose/imunologia , Aterosclerose/prevenção & controle , Aterosclerose/terapia , Fatores de Risco de Doenças Cardíacas , Inflamação , Vacinação/tendências , Imunidade Inata/imunologia , Imunidade Adaptativa/imunologia , Imunidade Humoral/imunologia , Autoantígenos/imunologia , Ensaios Clínicos como Assunto , Vacinas/imunologia , Vacinas/uso terapêutico
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