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1.
Immunogenetics ; 71(8-9): 561-573, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31506710

RESUMO

The major histocompatibility complex (MHC) is critical to host-pathogen interactions. Class II MHC is a heterodimer, with α and ß subunits encoded by different genes. The peptide-binding groove is formed by the first domain of both subunits (α1 and ß1), but studies of class II variation or natural selection focus primarily on the ß subunit and II B genes. We explored MHC II A in Leach's storm-petrel, a seabird with two expressed, polymorphic II B genes. We found two II A genes, Ocle-DAA and Ocle-DBA, in contrast to the single II A gene in chicken and duck. In exon 2 which encodes the α1 domain, the storm-petrel II A genes differed strongly from each other but showed little within-gene polymorphism in 30 individuals: just one Ocle-DAA allele, and three Ocle-DBA alleles differing from each other by single non-synonymous substitutions. In a comparable sample, the two II B genes had nine markedly diverged alleles each. Differences between the α1 domains of Ocle-DAA and Ocle-DBA showed signatures of positive selection, but mainly at non-peptide-binding site (PBS) positions. In contrast, positive selection within and between the II B genes corresponded to putative PBS codons. Phylogenetic analysis of the conserved α2 domain did not reveal deep or well-supported lineages of II A genes in birds, in contrast to the pronounced differentiation of DQA, DPA, and DRA isotypes in mammals. This uncertain homology complicates efforts to compare levels of functional variation and modes of evolution of II A genes across taxa.


Assuntos
Proteínas Aviárias/genética , Aves/genética , Evolução Molecular , Antígenos de Histocompatibilidade Classe II/genética , Polimorfismo Genético , Sequência de Aminoácidos , Animais , Proteínas Aviárias/imunologia , Sequência de Bases , Aves/imunologia , Éxons , Feminino , Frequência do Gene , Antígenos de Histocompatibilidade Classe II/imunologia , Masculino , Filogenia , Homologia de Sequência
2.
Cancer Immunol Immunother ; 68(11): 1865-1873, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31448380

RESUMO

It is well recognized that CD4+ T cells may play an important role in immunosurveillance and immunotherapy against cancer. However, the details of how these cells recognize and eliminate the tumor cells remain incompletely understood. For the past 25 years, we have focused on how CD4+ T cells reject multiple myeloma cells in a murine model (MOPC315). In our experimental system, the secreted tumor-specific antigen is taken up by tumor-infiltrating macrophages that process it and present a neoepitope [a V region-derived idiotypic (Id) peptide] on MHC class II molecules to Th1 cells. Stimulated Th1 cells produce IFNγ, which activates macrophages in a manner that elicits an M1-like, tumoricidal phenotype. Through an inducible nitric oxide synthetase (iNOS)-dependent mechanism, the M1 macrophages secrete nitric oxide (NO) that diffuses into neighboring tumor cells. Inside the tumor cells, NO-derived reactive nitrogen species, including peroxynitrite, causes nitrosylation of proteins and triggers apoptosis by the intrinsic apoptotic pathway. This mode of indirect tumor recognition by CD4+ T cells operates independently of MHC class II expression on cancer cells. However, secretion of the tumor-specific antigen, and uptake and MHCII presentation on macrophages, is required for rejection. Similar mechanisms can also be observed in a B-lymphoma model and in the unrelated B16 melanoma model. Our findings reveal a novel mechanism by which CD4+ T cells kill tumor cells indirectly via induction of intratumoral cytotoxic macrophages. The data suggest that induction of M1 polarization of tumor-infiltrating macrophages, by CD4+ T cells or through other means, could serve as an immunotherapeutic strategy.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Macrófagos/imunologia , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/terapia , Animais , Antígenos de Neoplasias/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Imunoterapia/métodos , Camundongos , Células Th1/imunologia
3.
Immunogenetics ; 71(7): 445-454, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31183519

RESUMO

Major histocompatibility complex (MHC) class II antigen presentation is a key component in eliciting a CD4+ T cell response. Precise prediction of peptide-MHC (pMHC) interactions has thus become a cornerstone in defining epitope candidates for rational vaccine design. Current pMHC prediction tools have, so far, primarily focused on inference from in vitro binding affinity. In the current study, we collate a large set of MHC class II eluted ligands generated by mass spectrometry to guide the prediction of MHC class II antigen presentation. We demonstrate that models developed on eluted ligands outperform those developed on pMHC binding affinity data. The predictive performance can be further enhanced by combining the eluted ligand and pMHC affinity data in a single prediction model. Furthermore, by including ligand data, the peptide length preference of MHC class II can be accurately learned by the prediction model. Finally, we demonstrate that our model significantly outperforms the current state-of-the-art prediction method, NetMHCIIpan, on an external dataset of eluted ligands and appears superior in identifying CD4+ T cell epitopes.


Assuntos
Biologia Computacional/métodos , Antígenos de Histocompatibilidade Classe II/metabolismo , Peptídeos/metabolismo , Apresentação do Antígeno , Bases de Dados de Proteínas , Epitopos de Linfócito T , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Ligantes , Ligação Proteica , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
4.
Pol J Microbiol ; 68(2): 233-246, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31250594

RESUMO

The aim of this study was to identify the potential vaccine antigens in Corynebacterium diphtheriae strains by in silico analysis of the amino acid variation in the 67-72p surface protein that is involved in the colonization and induction of epithelial cell apoptosis in the early stages of infection. The analysis of pili structural proteins involved in bacterial adherence to host cells and related to various types of infections was also performed. A polymerase chain reaction (PCR) was carried out to amplify the genes encoding the 67-72p protein and three pili structural proteins (SpaC, SpaI, SapD) and the products obtained were sequenced. The nucleotide sequences of the particular genes were translated into amino acid sequences, which were then matched among all the tested strains using bioinformatics tools. In the last step, the affinity of the tested proteins to major histocompatibility complex (MHC) classes I and II, and linear B-cell epitopes was analyzed. The variations in the nucleotide sequence of the 67-72p protein and pili structural proteins among C. diphtheriae strains isolated from various infections were noted. A transposition of the insertion sequence within the gene encoding the SpaC pili structural proteins was also detected. In addition, the bioinformatics analyses enabled the identification of epitopes for B-cells and T-cells in the conserved regions of the proteins, thus, demonstrating that these proteins could be used as antigens in the potential vaccine development. The results identified the most conserved regions in all tested proteins that are exposed on the surface of C. diphtheriae cells.The aim of this study was to identify the potential vaccine antigens in Corynebacterium diphtheriae strains by in silico analysis of the amino acid variation in the 67­72p surface protein that is involved in the colonization and induction of epithelial cell apoptosis in the early stages of infection. The analysis of pili structural proteins involved in bacterial adherence to host cells and related to various types of infections was also performed. A polymerase chain reaction (PCR) was carried out to amplify the genes encoding the 67­72p protein and three pili structural proteins (SpaC, SpaI, SapD) and the products obtained were sequenced. The nucleotide sequences of the particular genes were translated into amino acid sequences, which were then matched among all the tested strains using bioinformatics tools. In the last step, the affinity of the tested proteins to major histocompatibility complex (MHC) classes I and II, and linear B-cell epitopes was analyzed. The variations in the nucleotide sequence of the 67­72p protein and pili structural proteins among C. diphtheriae strains isolated from various infections were noted. A transposition of the insertion sequence within the gene encoding the SpaC pili structural proteins was also detected. In addition, the bioinformatics analyses enabled the identification of epitopes for B-cells and T-cells in the conserved regions of the proteins, thus, demonstrating that these proteins could be used as antigens in the potential vaccine development. The results identified the most conserved regions in all tested proteins that are exposed on the surface of C. diphtheriae cells.


Assuntos
Adesinas Bacterianas/genética , Antígenos de Bactérias/genética , Corynebacterium diphtheriae/genética , Toxoide Diftérico/genética , Difteria/prevenção & controle , Variação Genética , Proteínas de Membrana/genética , Adesinas Bacterianas/imunologia , Antígenos de Bactérias/imunologia , Biologia Computacional , Sequência Conservada , Corynebacterium diphtheriae/imunologia , Toxoide Diftérico/imunologia , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Proteínas de Membrana/imunologia , Reação em Cadeia da Polimerase , Ligação Proteica , Análise de Sequência de DNA
5.
Nat Commun ; 10(1): 2150, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089130

RESUMO

Peptide-major histocompatibility complex class II (pMHCII)-based nanomedicines displaying tissue-specific autoantigenic epitopes can blunt specific autoimmune conditions by re-programming cognate antigen-experienced CD4+ T-cells into disease-suppressing T-regulatory type 1 (TR1) cells. Here, we show that single pMHCII-based nanomedicines displaying epitopes from mitochondrial, endoplasmic reticulum or cytoplasmic antigens associated with primary biliary cholangitis (PBC) or autoimmune hepatitis (AIH) can broadly blunt PBC, AIH and Primary Sclerosing Cholangitis in various murine models in an organ- rather than disease-specific manner, without suppressing general or local immunity against infection or metastatic tumors. Therapeutic activity is associated with cognate TR1 cell formation and expansion, TR1 cell recruitment to the liver and draining lymph nodes, local B-regulatory cell formation and profound suppression of the pro-inflammatory capacity of liver and liver-proximal myeloid dendritic cells and Kupffer cells. Thus, autoreactivity against liver-enriched autoantigens in liver autoimmunity is not disease-specific and can be harnessed to treat various liver autoimmune diseases broadly.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Antígenos de Histocompatibilidade Classe II/imunologia , Hepatopatias/tratamento farmacológico , Nanopartículas/administração & dosagem , Peptídeos/administração & dosagem , Idoso , Animais , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Linhagem Celular , Modelos Animais de Doenças , Epitopos/imunologia , Feminino , Antígenos de Histocompatibilidade Classe II/química , Humanos , Fígado/efeitos dos fármacos , Fígado/imunologia , Hepatopatias/imunologia , Masculino , Camundongos , Pessoa de Meia-Idade , Nanomedicina/métodos , Nanopartículas/química , Peptídeos/química , Peptídeos/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia
6.
Immunity ; 50(5): 1188-1201.e6, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31053504

RESUMO

Lymph nodes (LNs) play critical roles in adaptive immunity by concentrating in one location the antigens, antigen-presenting cells, and antigen-responsive lymphocytes involved in such responses. Recent studies have revealed nonrandom localization of innate and adaptive immune cells within these organs, suggesting that microanatomical positioning optimizes responses involving sparse cooperating cells. Here, we report that the peripheral localization of LN cDC2 dendritic cells specialized for MHC-II antigen presentation is matched by a similarly biased paracortical distribution of CD4+ T cells directed by the chemoattractant receptor Ebi2. In the absence of Ebi2, CD4+ T cells lose their location bias and are delayed in antigen recognition, proliferative expansion, differentiation, direct effector activity, and provision of help for CD8+ T cell-mediated memory responses, limiting host defense and vaccine responses. These findings demonstrate evolutionary selection for distinct niches within the LN that promote cellular responses, emphasizing the critical link between fine-grained tissue organization and host defense.


Assuntos
Imunidade Adaptativa/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Apresentação do Antígeno/imunologia , Antígenos/imunologia , Diferenciação Celular/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Linfonodos/citologia , Linfonodos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas-G/genética
7.
Nat Immunol ; 20(7): 928-942, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31061532

RESUMO

To define the cell populations that drive joint inflammation in rheumatoid arthritis (RA), we applied single-cell RNA sequencing (scRNA-seq), mass cytometry, bulk RNA sequencing (RNA-seq) and flow cytometry to T cells, B cells, monocytes, and fibroblasts from 51 samples of synovial tissue from patients with RA or osteoarthritis (OA). Utilizing an integrated strategy based on canonical correlation analysis of 5,265 scRNA-seq profiles, we identified 18 unique cell populations. Combining mass cytometry and transcriptomics revealed cell states expanded in RA synovia: THY1(CD90)+HLA-DRAhi sublining fibroblasts, IL1B+ pro-inflammatory monocytes, ITGAX+TBX21+ autoimmune-associated B cells and PDCD1+ peripheral helper T (TPH) cells and follicular helper T (TFH) cells. We defined distinct subsets of CD8+ T cells characterized by GZMK+, GZMB+, and GNLY+ phenotypes. We mapped inflammatory mediators to their source cell populations; for example, we attributed IL6 expression to THY1+HLA-DRAhi fibroblasts and IL1B production to pro-inflammatory monocytes. These populations are potentially key mediators of RA pathogenesis.


Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Perfilação da Expressão Gênica , Membrana Sinovial/metabolismo , Transcriptoma , Artrite Reumatoide/patologia , Autoimunidade/genética , Biomarcadores , Biologia Computacional/métodos , Estudos Transversais , Citocinas/metabolismo , Fibroblastos/metabolismo , Citometria de Fluxo , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Leucócitos/imunologia , Leucócitos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Transdução de Sinais , Análise de Célula Única/métodos , Membrana Sinovial/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Fluxo de Trabalho
8.
Immunogenetics ; 71(5-6): 407-420, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31037384

RESUMO

Major histocompatibility complex (MHC) class II-associated invariant chain is a chaperone responsible for targeting the MHC class II dimer to the endocytic pathway, thus enabling the loading of exogenous antigens onto the MHC class II receptor. In the current study, in vivo and in vitro methods were used to investigate the regulation of the rainbow trout invariant chain proteins S25-7 and INVX, upon immune system activation. Whole rainbow trout and the macrophage/monocyte-like cell line RTS11 were treated with PMA at concentrations shown to induce IL-1ß transcripts and homotypic aggregation of RTS11. S25-7 transcript levels remained unchanged in the gill, spleen, and liver and were found to be significantly decreased in head kidney beginning 24 h post-stimulation. Meanwhile, INVX transcript levels remained unchanged in all tissues studied. Both S25-7 and INVX proteins were produced in gill and spleen tissues but their expression was unaffected by immune system stimulation. Surprisingly, neither INVX nor S25-7 protein was detected in the secondary immune organ, the head kidney. Analysis of RTS11 cultures demonstrated that both INVX and S25-7 transcript levels significantly increased at 96 h and 120 h following PMA stimulation before returning to control levels at 168 h. Meanwhile, at the protein level in RTS11, S25-7 remained unchanged while INVX had a significant decrease at 168 h post-stimulation. These results indicate that neither INVX nor S25-7 is upregulated upon immune system activation; thus, teleosts have evolved a system of immune regulation that is different than that found in mammals.


Assuntos
Antígenos de Diferenciação de Linfócitos B/genética , Antígenos de Diferenciação de Linfócitos B/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Imunomodulação/genética , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/imunologia , Imunidade Adaptativa , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Imunização , Macrófagos/imunologia , Macrófagos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Isoformas de Proteínas , Transcriptoma
9.
PLoS Genet ; 15(4): e1008092, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31022184

RESUMO

Human leukocyte antigen (HLA) is a key genetic factor conferring risk of systemic lupus erythematosus (SLE), but precise independent localization of HLA effects is extremely challenging. As a result, the contribution of specific HLA alleles and amino-acid residues to the overall risk of SLE and to risk of specific autoantibodies are far from completely understood. Here, we dissected (a) overall SLE association signals across HLA, (b) HLA-peptide interaction, and (c) residue-autoantibody association. Classical alleles, SNPs, and amino-acid residues of eight HLA genes were imputed across 4,915 SLE cases and 13,513 controls from Eastern Asia. We performed association followed by conditional analysis across HLA, assessing both overall SLE risk and risk of autoantibody production. DR15 alleles HLA-DRB1*15:01 (P = 1.4x10-27, odds ratio (OR) = 1.57) and HLA-DQB1*06:02 (P = 7.4x10-23, OR = 1.55) formed the most significant haplotype (OR = 2.33). Conditioned protein-residue signals were stronger than allele signals and mapped predominantly to HLA-DRB1 residue 13 (P = 2.2x10-75) and its proxy position 11 (P = 1.1x10-67), followed by HLA-DRB1-37 (P = 4.5x10-24). After conditioning on HLA-DRB1, novel associations at HLA-A-70 (P = 1.4x10-8), HLA-DPB1-35 (P = 9.0x10-16), HLA-DQB1-37 (P = 2.7x10-14), and HLA-B-9 (P = 6.5x10-15) emerged. Together, these seven residues increased the proportion of explained heritability due to HLA to 2.6%. Risk residues for both overall disease and hallmark autoantibodies (i.e., nRNP: DRB1-11, P = 2.0x10-14; DRB1-13, P = 2.9x10-13; DRB1-30, P = 3.9x10-14) localized to the peptide-binding groove of HLA-DRB1. Enrichment for specific amino-acid characteristics in the peptide-binding groove correlated with overall SLE risk and with autoantibody presence. Risk residues were in primarily negatively charged side-chains, in contrast with rheumatoid arthritis. We identified novel SLE signals in HLA Class I loci (HLA-A, HLA-B), and localized primary Class II signals to five residues in HLA-DRB1, HLA-DPB1, and HLA-DQB1. These findings provide insights about the mechanisms by which the risk residues interact with each other to produce autoantibodies and are involved in SLE pathophysiology.


Assuntos
Sequência de Aminoácidos , Autoanticorpos/imunologia , Suscetibilidade a Doenças , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/imunologia , Lúpus Eritematoso Sistêmico/etiologia , Alelos , Substituição de Aminoácidos , Grupo com Ancestrais do Continente Asiático , Feminino , Predisposição Genética para Doença , Variação Genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Masculino , Razão de Chances , Polimorfismo de Nucleotídeo Único
10.
PLoS Pathog ; 15(3): e1007643, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30830940

RESUMO

Eradication of tuberculosis (TB), the world's leading cause of death due to infectious disease, requires a highly efficacious TB vaccine. Many TB vaccine candidates are in pre-clinical and clinical development but only a few can be advanced to large-scale efficacy trials due to limited global resources. We aimed to perform a statistically rigorous comparison of the antigen-specific T cell responses induced by six novel TB vaccine candidates and the only licensed TB vaccine, Bacillus Calmette-Guérin (BCG). We propose that the antigen-specific immune response induced by such vaccines provides an objective, data-driven basis for prioritisation of vaccine candidates for efficacy testing. We analyzed frequencies of antigen-specific CD4 and CD8 T cells expressing IFNγ, IL-2, TNF and/or IL-17 from adolescents or adults, with or without Mycobacterium tuberculosis (M.tb) infection, who received MVA85A, AERAS-402, H1:IC31, H56:IC31, M72/AS01E, ID93+GLA-SE or BCG. Two key response characteristics were analyzed, namely response magnitude and cytokine co-expression profile of the memory T cell response that persisted above the pre-vaccination response to the final study visit in each trial. All vaccines preferentially induced antigen-specific CD4 T cell responses expressing Th1 cytokines; levels of IL-17-expressing cells were low or not detected. In M.tb-uninfected and -infected individuals, M72/AS01E induced higher memory Th1 cytokine-expressing CD4 T cell responses than other novel vaccine candidates. Cytokine co-expression profiles of memory CD4 T cells induced by different novel vaccine candidates were alike. Our study suggests that the T cell response feature which most differentiated between the TB vaccine candidates was response magnitude, whilst functional profiles suggested a lack of response diversity. Since M72/AS01E induced the highest memory CD4 T cell response it demonstrated the best vaccine take. In the absence of immunological correlates of protection, the likelihood of finding a protective vaccine by empirical testing of candidates may be increased by the addition of candidates that induce distinct immune characteristics.


Assuntos
Mycobacterium tuberculosis/imunologia , Vacinas contra a Tuberculose/metabolismo , Vacinas contra a Tuberculose/farmacologia , Adjuvantes Imunológicos/farmacologia , Adolescente , Adulto , Antígenos de Bactérias , Vacina BCG , Linfócitos T CD4-Positivos , Citocinas , Combinação de Medicamentos , Feminino , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunidade Humoral/imunologia , Imunidade Humoral/fisiologia , Interferon gama , Interleucina-17 , Interleucina-2 , Lipídeo A/análogos & derivados , Masculino , Mycobacterium bovis , Mycobacterium tuberculosis/patogenicidade , Saponinas , Células Th1 , Tuberculose/imunologia , Tuberculose/metabolismo , Fator de Necrose Tumoral alfa
11.
Adv Mater ; 31(18): e1900499, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30907473

RESUMO

Using the cytomembranes (FMs) of hybrid cells acquired from the fusion of cancer and dendritic cells (DCs), this study offers a biologically derived platform for the combination of immunotherapy and traditional oncotherapy approaches. Due to the immunoactivation implicated in the cellular fusion, FMs can effectively express whole cancer antigens and immunological co-stimulatory molecules for robust immunotherapy. FMs share the tumor's self-targeting character with the parent cancer cells. In bilateral tumor-bearing mouse models, the FM-coated nanophotosensitizer causes durable immunoresponse to inhibit the rebound of primary tumors post-nanophotosensitizer-induced photodynamic therapy (PDT). The FM-induced immunotherapy displays ultrahigh antitumor effects even comparable to that of PDT. On the other hand, PDT toward primary tumors enhances the immunotherapy-caused regression of the irradiation-free distant tumors. Consequently, both the primary and the distant tumors are almost completely eliminated. This tumor-specific immunotherapy-based nanoplatform is potentially expandable to multiple tumor types and readily equipped with diverse functions owing to the flexible nanoparticle options.


Assuntos
Membrana Celular/química , Células Dendríticas/citologia , Imunoterapia , Nanoestruturas/química , Animais , Anticorpos/química , Anticorpos/imunologia , Linhagem Celular Tumoral , Células Dendríticas/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Receptores de Hialuronatos/imunologia , Estruturas Metalorgânicas/química , Camundongos , Camundongos Nus , Nanoestruturas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/química , Porfirinas/uso terapêutico , Transplante Heterólogo , Zircônio/química
12.
Dev Comp Immunol ; 96: 126-134, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30853539

RESUMO

The major histocompatibility complex (MHC) genes show high polymorphisms in vertebrates depending on animal immunity status. Herein, MHC class IIA gene in Aeromonas hydrophila-challenged Nile tilapia was screened for presence of polymorphisms using sequencing. Twelve nucleotides deletion polymorphism was determined with a PCR product size of 267 bp in the resistant fish and 255 bp in the control and susceptible/diseased fish. Additionally, a non-synonymous right frameshift c.712 T > G (P. 238 * > G) SNP was detected at the stop codon (*). SNP-susceptibility association analysis revealed that fish carrying GG genotype and allele G were high susceptible (risk) for A. hydrophila, and had lower immune response as indicated by significant reduction in non-specific immune parameters (total protein, globulin, IgM, phagocytic activity, phagocytic index, and lysosome activity) and mRNA level of MHC IIA, interleukin 1 beta (IL1ß), tumor necrosis factor alfa (TNFα), and toll-like receptor 7 (TLR7) in the spleen and head kidney. Thus, G allele could be considered as a risk (recessive or mutant) allele for c. 712 T > G (P. 238 * > G) SNP and so selection of Nile tilapia with protective allele (T) for this SNP could improve the disease resistant of the fish.


Assuntos
Aeromonas hydrophila/patogenicidade , Ciclídeos/imunologia , Doenças dos Peixes/imunologia , Genes MHC da Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Aeromonas hydrophila/imunologia , Alelos , Animais , Ciclídeos/genética , Ciclídeos/microbiologia , Resistência à Doença/genética , Resistência à Doença/imunologia , Doenças dos Peixes/genética , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas , Rim Cefálico/imunologia , Rim Cefálico/metabolismo , Rim Cefálico/microbiologia , Antígenos de Histocompatibilidade Classe II/genética , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Polimorfismo Genético/imunologia , Baço/imunologia , Baço/metabolismo , Baço/microbiologia
13.
Diabetes ; 68(5): 988-1001, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30833470

RESUMO

Type 1 diabetes studies consistently generate data showing islet ß-cell dysfunction and T cell-mediated anti-ß-cell-specific autoimmunity. To explore the pathogenesis, we interrogated the ß-cell transcriptomes from donors with and without type 1 diabetes using both bulk-sorted and single ß-cells. Consistent with immunohistological studies, ß-cells from donors with type 1 diabetes displayed increased Class I transcripts and associated mRNA species. These ß-cells also expressed mRNA for Class II and Class II antigen presentation pathway components, but lacked the macrophage marker CD68. Immunohistological study of three independent cohorts of donors with recent-onset type 1 diabetes showed Class II protein and its transcriptional regulator Class II MHC trans-activator protein expressed by a subset of insulin+CD68- ß-cells, specifically found in islets with lymphocytic infiltrates. ß-Cell surface expression of HLA Class II was detected on a portion of CD45-insulin+ ß-cells from donors with type 1 diabetes by immunofluorescence and flow cytometry. Our data demonstrate that pancreatic ß-cells from donors with type 1 diabetes express Class II molecules on selected cells with other key genes in those pathways and inflammation-associated genes. ß-Cell expression of Class II molecules suggests that ß-cells may interact directly with islet-infiltrating CD4+ T cells and may play an immunopathogenic role.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Apresentação do Antígeno/imunologia , Autoimunidade/fisiologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Humanos , Insulina/metabolismo
14.
PLoS Pathog ; 15(2): e1007567, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30789961

RESUMO

Most studies of T lymphocytes focus on recognition of classical major histocompatibility complex (MHC) class I or II molecules presenting oligopeptides, yet there are numerous variations and exceptions of biological significance based on recognition of a wide variety of nonclassical MHC molecules. These include αß and γδ T cells that recognize different class Ib molecules (CD1, MR-1, HLA-E, G, F, et al.) that are nearly monomorphic within a given species. Collectively, these T cells can be considered "unconventional," in part because they recognize lipids, metabolites, and modified peptides. Unlike classical MHC-specific cells, unconventional T cells generally exhibit limited T-cell antigen receptor (TCR) repertoires and often produce innate immune cell-like rapid effector responses. Exploiting this system in new generation vaccines for human immunodeficiency virus (HIV), tuberculosis (TB), other infectious agents, and cancer was the focus of a recent workshop, "Immune Surveillance by Non-classical MHC Molecules: Improving Diversity for Antigens," sponsored by the National Institute of Allergy and Infectious Diseases. Here, we summarize salient points presented regarding the basic immunobiology of unconventional T cells, recent advances in methodologies to measure unconventional T-cell activity in diseases, and approaches to harness their considerable clinical potential.


Assuntos
Vigilância Imunológica/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Animais , Antígenos , Antígenos HLA , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Receptores de Antígenos de Linfócitos T , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T/imunologia
15.
Blood ; 133(10): 1108-1118, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30700420

RESUMO

Best known for presenting antigenic peptides to CD4+ T cells, major histocompatibility complex class II (MHC II) also transmits or may modify intracellular signals. Here, we show that MHC II cell-autonomously regulates the balance between self-renewal and differentiation in B-cell precursors, as well as in malignant B cells. Initiation of MHC II expression early during bone marrow B-cell development limited the occupancy of cycling compartments by promoting differentiation, thus regulating the numerical output of B cells. MHC II deficiency preserved stem cell characteristics in developing pro-B cells in vivo, and ectopic MHC II expression accelerated hematopoietic stem cell differentiation in vitro. Moreover, MHC II expression restrained growth of murine B-cell leukemia cell lines in vitro and in vivo, independently of CD4+ T-cell surveillance. Our results highlight an important cell-intrinsic contribution of MHC II expression to establishing the differentiated B-cell phenotype.


Assuntos
Linfócitos B/imunologia , Diferenciação Celular , Antígenos de Histocompatibilidade Classe II/imunologia , Animais , Apresentação do Antígeno , Medula Óssea , Células da Medula Óssea/citologia , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Progressão da Doença , Feminino , Antígenos de Histocompatibilidade Classe II/genética , Proteínas de Homeodomínio/genética , Leucemia de Células B/imunologia , Ativação Linfocitária/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Immunogenetics ; 71(4): 335-346, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30761419

RESUMO

Infectious diseases are causing catastrophic losses to global biodiversity. Iridoviruses in the genus Ranavirus are among the leading causes of amphibian disease-related mortality. Polymorphisms in major histocompatibility complex (MHC) genes are significantly associated with variation in amphibian pathogen susceptibility. MHC genes encode two classes of polymorphic cell-surface molecules that can recognize and bind to diverse pathogen peptides. While MHC class I genes are the classic mediators of viral-acquired immunity, larval amphibians do not express them. Consequently, MHC class II gene diversity may be an important predictor of Ranavirus susceptibility in larval amphibians, the life stage most susceptible to Ranavirus. We surveyed natural populations of larval wood frogs (Rana sylvatica), which are highly susceptible to Ranavirus, across 17 ponds and 2 years in Maryland, USA. We sequenced the peptide-binding region of an expressed MHC class IIß locus and assessed allelic and genetic diversity. We converted alleles to functional supertypes and determined if supertypes or alleles influenced host responses to Ranavirus. Among 381 sampled individuals, 26% were infected with Ranavirus. We recovered 20 unique MHC class IIß alleles that fell into two deeply diverged clades and seven supertypes. MHC genotypes were associated with Ranavirus infection intensity, but not prevalence. Specifically, MHC heterozygotes and supertype ST1/ST7 had significantly lower Ranavirus infection intensity compared to homozygotes and other supertypes. We conclude that MHC class IIß functional genetic variation is an important component of Ranavirus susceptibility. Identifying immunogenetic signatures linked to variation in disease susceptibility can inform mitigation strategies for combatting global amphibian declines.


Assuntos
Antígenos de Histocompatibilidade Classe II/imunologia , Polimorfismo Genético , Ranavirus/imunologia , Ranidae/imunologia , Alelos , Animais , Frequência do Gene , Predisposição Genética para Doença/genética , Antígenos de Histocompatibilidade Classe II/classificação , Antígenos de Histocompatibilidade Classe II/genética , Larva/genética , Larva/imunologia , Larva/virologia , Maryland , Filogenia , Ranavirus/fisiologia , Ranidae/genética , Ranidae/virologia
17.
Nature ; 567(7746): 109-112, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30787439

RESUMO

Zoonotic influenza A viruses of avian origin can cause severe disease in individuals, or even global pandemics, and thus pose a threat to human populations. Waterfowl and shorebirds are believed to be the reservoir for all influenza A viruses, but this has recently been challenged by the identification of novel influenza A viruses in bats1,2. The major bat influenza A virus envelope glycoprotein, haemagglutinin, does not bind the canonical influenza A virus receptor, sialic acid or any other glycan1,3,4, despite its high sequence and structural homology with conventional haemagglutinins. This functionally uncharacterized plasticity of the bat influenza A virus haemagglutinin means the tropism and zoonotic potential of these viruses has not been fully determined. Here we show, using transcriptomic profiling of susceptible versus non-susceptible cells in combination with genome-wide CRISPR-Cas9 screening, that the major histocompatibility complex class II (MHC-II) human leukocyte antigen DR isotype (HLA-DR) is an essential entry determinant for bat influenza A viruses. Genetic ablation of the HLA-DR α-chain rendered cells resistant to infection by bat influenza A virus, whereas ectopic expression of the HLA-DR complex in non-susceptible cells conferred susceptibility. Expression of MHC-II from different bat species, pigs, mice or chickens also conferred susceptibility to infection. Notably, the infection of mice with bat influenza A virus resulted in robust virus replication in the upper respiratory tract, whereas mice deficient for MHC-II were resistant. Collectively, our data identify MHC-II as a crucial entry mediator for bat influenza A viruses in multiple species, which permits a broad vertebrate tropism.


Assuntos
Quirópteros/virologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Especificidade de Hospedeiro , Vírus da Influenza A/imunologia , Vírus da Influenza A/fisiologia , Zoonoses/imunologia , Zoonoses/virologia , Animais , Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Galinhas/genética , Galinhas/imunologia , Quirópteros/genética , Quirópteros/imunologia , Quirópteros/metabolismo , Feminino , Perfilação da Expressão Gênica , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Especificidade de Hospedeiro/genética , Especificidade de Hospedeiro/imunologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Sistema Respiratório/virologia , Suínos/genética , Suínos/imunologia , Tropismo Viral/genética , Tropismo Viral/imunologia , Replicação Viral , Zoonoses/genética , Zoonoses/metabolismo
18.
PLoS Biol ; 17(1): e3000131, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30703088

RESUMO

Central players of the adaptive immune system are the groups of proteins encoded in the major histocompatibility complex (MHC), which shape the immune response against pathogens and tolerance to self-peptides. The corresponding genomic region is of particular interest, as it harbors more disease associations than any other region in the human genome, including associations with infectious diseases, autoimmune disorders, cancers, and neuropsychiatric diseases. Certain MHC molecules can bind to a much wider range of epitopes than others, but the functional implication of such an elevated epitope-binding repertoire has remained largely unclear. It has been suggested that by recognizing more peptide segments, such promiscuous MHC molecules promote immune response against a broader range of pathogens. If so, the geographical distribution of MHC promiscuity level should be shaped by pathogen diversity. Three lines of evidence support the hypothesis. First, we found that in pathogen-rich geographical regions, humans are more likely to carry highly promiscuous MHC class II DRB1 alleles. Second, the switch between specialist and generalist antigen presentation has occurred repeatedly and in a rapid manner during human evolution. Third, molecular positions that define promiscuity level of MHC class II molecules are especially diverse and are under positive selection in human populations. Taken together, our work indicates that pathogen load maintains generalist adaptive immune recognition, with implications for medical genetics and epidemiology.


Assuntos
Imunidade Adaptativa/genética , Antígenos de Histocompatibilidade Classe II/genética , Complexo Principal de Histocompatibilidade/genética , Sequência de Aminoácidos/genética , Animais , Apresentação do Antígeno/genética , Apresentação do Antígeno/imunologia , Evolução Biológica , Patógenos Transmitidos pelo Sangue , Epitopos/genética , Epitopos/fisiologia , Evolução Molecular , Variação Genética/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Complexo Principal de Histocompatibilidade/fisiologia , Peptídeos/genética , Seleção Genética/genética
19.
Mar Drugs ; 17(1)2019 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-30669428

RESUMO

In our previous study, we showed that ascophyllan purified from Ascophyllum nodosum treatment promotes mouse dendritic cell (DC) activation in vivo, further induces an antigen-specific immune response and has anticancer effects in mice. However, the effect of ascophyllan has not been studied in human immune cells, specifically in terms of activation of human monocyte-derived DCs (MDDCs) and human peripheral blood DCs (PBDCs). We found that the treatment with ascophyllan induced morphological changes in MDDCs and upregulated co-stimulatory molecules and major histocompatibility complex class I (MHC I) and MHC II expression. In addition, pro-inflammatory cytokine levels in culture medium was also dramatically increased following ascophyllan treatment of MDDCs. Moreover, ascophyllan promoted phosphorylation of ERK, p38 and JNK signaling pathways, and inhibition of p38 almost completely suppressed the ascophyllan-induced activation of MDDCs. Finally, treatment with ascophyllan induced activation of BDCA1 and BDCA3 PBDCs. Thus, these data suggest that ascophyllan could be used as an immune stimulator in humans.


Assuntos
Organismos Aquáticos/química , Ascophyllum/química , Células Dendríticas/efeitos dos fármacos , Imunidade Celular/efeitos dos fármacos , Polissacarídeos/farmacologia , Antígenos CD1/metabolismo , Antígenos de Superfície/metabolismo , Diferenciação Celular , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Glicoproteínas/metabolismo , Voluntários Saudáveis , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imunidade Celular/imunologia , Leucócitos Mononucleares , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Fosforilação/efeitos dos fármacos , Polissacarídeos/isolamento & purificação
20.
Science ; 363(6425)2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30679343

RESUMO

The innate immune cell compartment is highly diverse in the healthy central nervous system (CNS), including parenchymal and non-parenchymal macrophages. However, this complexity is increased in inflammatory settings by the recruitment of circulating myeloid cells. It is unclear which disease-specific myeloid subsets exist and what their transcriptional profiles and dynamics during CNS pathology are. Combining deep single-cell transcriptome analysis, fate mapping, in vivo imaging, clonal analysis, and transgenic mouse lines, we comprehensively characterized unappreciated myeloid subsets in several CNS compartments during neuroinflammation. During inflammation, CNS macrophage subsets undergo self-renewal, and random proliferation shifts toward clonal expansion. Last, functional studies demonstrated that endogenous CNS tissue macrophages are redundant for antigen presentation. Our results highlight myeloid cell diversity and provide insights into the brain's innate immune system.


Assuntos
Sistema Nervoso Central/imunologia , Imunidade Inata , Inflamação/imunologia , Macrófagos/citologia , Células Mieloides/citologia , Animais , Apresentação do Antígeno , Encéfalo/imunologia , Células Dendríticas/citologia , Encefalomielite Autoimune Experimental/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Homeostase , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Monócitos/citologia , Células Mieloides/imunologia , Análise de Sequência de RNA , Análise de Célula Única , Linfócitos T/imunologia
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