Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 77
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Cell ; 185(21): 3992-4007.e16, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36198317

RESUMEN

After the global spread of the SARS-CoV-2 Omicron BA.2, some BA.2 subvariants, including BA.2.9.1, BA.2.11, BA.2.12.1, BA.4, and BA.5, emerged in multiple countries. Our statistical analysis showed that the effective reproduction numbers of these BA.2 subvariants are greater than that of the original BA.2. Neutralization experiments revealed that the immunity induced by BA.1/2 infections is less effective against BA.4/5. Cell culture experiments showed that BA.2.12.1 and BA.4/5 replicate more efficiently in human alveolar epithelial cells than BA.2, and particularly, BA.4/5 is more fusogenic than BA.2. We further provided the structure of the BA.4/5 spike receptor-binding domain that binds to human ACE2 and considered how the substitutions in the BA.4/5 spike play roles in ACE2 binding and immune evasion. Moreover, experiments using hamsters suggested that BA.4/5 is more pathogenic than BA.2. Our multiscale investigations suggest that the risk of BA.2 subvariants, particularly BA.4/5, to global health is greater than that of original BA.2.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Anticuerpos Antivirales , Humanos , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/metabolismo , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo
2.
Cell ; 185(12): 2103-2115.e19, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35568035

RESUMEN

Soon after the emergence and global spread of the SARS-CoV-2 Omicron lineage BA.1, another Omicron lineage, BA.2, began outcompeting BA.1. The results of statistical analysis showed that the effective reproduction number of BA.2 is 1.4-fold higher than that of BA.1. Neutralization experiments revealed that immunity induced by COVID vaccines widely administered to human populations is not effective against BA.2, similar to BA.1, and that the antigenicity of BA.2 is notably different from that of BA.1. Cell culture experiments showed that the BA.2 spike confers higher replication efficacy in human nasal epithelial cells and is more efficient in mediating syncytia formation than the BA.1 spike. Furthermore, infection experiments using hamsters indicated that the BA.2 spike-bearing virus is more pathogenic than the BA.1 spike-bearing virus. Altogether, the results of our multiscale investigations suggest that the risk of BA.2 to global health is potentially higher than that of BA.1.


Asunto(s)
COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Animales , COVID-19/virología , Cricetinae , Células Epiteliales , Humanos , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/genética
4.
J Immunol ; 212(3): 455-465, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38063488

RESUMEN

Immune checkpoint blockade (ICB) immunotherapies have emerged as promising strategies for the treatment of cancer; however, there remains a need to improve their efficacy. Determinants of ICB efficacy are the frequency of tumor mutations, the associated neoantigens, and the T cell response against them. Therefore, it is expected that neoantigen vaccinations that boost the antitumor T cell response would improve ICB therapy efficacy. The aim of this study was to develop a highly immunogenic vaccine using pattern recognition receptor agonists in combination with synthetic long peptides to induce potent neoantigen-specific T cell responses. We determined that the combination of the TLR9 agonist K-type CpG oligodeoxynucleotides (K3 CpG) with the STING agonist c-di-AMP (K3/c-di-AMP combination) significantly increased dendritic cell activation. We found that immunizing mice with 20-mer of either an OVA peptide, low-affinity OVA peptides, or neopeptides identified from mouse melanoma or lung mesothelioma, together with K3/c-di-AMP, induced potent Ag-specific T cell responses. The combined K3/c-di-AMP adjuvant formulation induced 10 times higher T cell responses against neopeptides than the TLR3 agonist polyinosinic:polycytidylic acid, a derivative of which is the leading adjuvant in clinical trials of neoantigen peptide vaccines. Moreover, we demonstrated that our K3/c-di-AMP vaccine formulation with 20-mer OVA peptide was capable of controlling tumor growth and improving survival in B16-F10-OVA tumor-bearing C57BL/6 mice and synergized with anti-PD-1 treatment. Together, our findings demonstrate that the K3/c-di-AMP vaccine formulation induces potent T cell immunity against synthetic long peptides and is a promising candidate to improve neoantigen vaccine platform.


Asunto(s)
Vacunas contra el Cáncer , Neoplasias , Vacunas , Animales , Ratones , Linfocitos T , Inhibidores de Puntos de Control Inmunológico , Receptor Toll-Like 9 , Ratones Endogámicos C57BL , Adyuvantes Inmunológicos , Antígenos , Péptidos
5.
Int Immunol ; 36(9): 451-464, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-38642134

RESUMEN

Chronic bone loss is an under-recognized complication of malaria, the underlying mechanism of which remains incompletely understood. We have previously shown that persistent accumulation of Plasmodium products in the bone marrow leads to chronic inflammation in osteoblast (OB) and osteoclast (OC) precursors causing bone loss through MyD88, an adaptor molecule for diverse inflammatory signals. However, the specific contribution of MyD88 signaling in OB or OC precursors in malaria-induced bone loss remains elusive. To assess the direct cell-intrinsic role of MyD88 signaling in adult bone metabolism under physiological and infection conditions, we used the Lox-Cre system to specifically deplete MyD88 in the OB or OC lineages. Mice lacking MyD88 primarily in the maturing OBs showed a comparable decrease in trabecular bone density by microcomputed tomography to that of controls after Plasmodium yoelii non-lethal infection. In contrast, mice lacking MyD88 in OC precursors showed significantly less trabecular bone loss than controls, suggesting that malaria-mediated inflammatory mediators are primarily controlled by MyD88 in the OC lineage. Surprisingly, however, depletion of MyD88 in OB, but not in OC, precursors resulted in reduced bone mass with decreased bone formation rates in the trabecular areas of femurs under physiological conditions. Notably, insulin-like growth factor-1, a key molecule for OB differentiation, was significantly lower locally and systemically when MyD88 was depleted in OBs. Thus, our data demonstrate an indispensable intrinsic role for MyD88 signaling in OB differentiation and bone formation, while MyD88 signaling in OC lineages plays a partial role in controlling malaria-induced inflammatory mediators and following bone pathology. These findings may lead to the identification of novel targets for specific intervention of bone pathologies, particularly in malaria-endemic regions.


Asunto(s)
Remodelación Ósea , Homeostasis , Malaria , Ratones Noqueados , Factor 88 de Diferenciación Mieloide , Osteoblastos , Osteoclastos , Animales , Factor 88 de Diferenciación Mieloide/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Malaria/inmunología , Osteoblastos/metabolismo , Osteoblastos/inmunología , Ratones , Osteoclastos/metabolismo , Osteoclastos/inmunología , Plasmodium yoelii/inmunología , Ratones Endogámicos C57BL
6.
Immunity ; 45(6): 1299-1310, 2016 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-28002730

RESUMEN

Particulate pollution is thought to function as an adjuvant that can induce allergic responses. However, the exact cell types and immunological factors that initiate the lung-specific immune responses are unclear. We found that upon intratracheal instillation, particulates such as aluminum salts and silica killed alveolar macrophages (AMs), which then released interleukin-1α (IL-1α) and caused inducible bronchus-associated lymphoid tissue (iBALT) formation in the lung. IL-1α release continued for up to 2 weeks after particulate exposure, and type-2 allergic immune responses were induced by the inhalation of antigen during IL-1α release and iBALT formation, even long after particulate instillation. Recombinant IL-1α was sufficient to induce iBALTs, which coincided with subsequent immunoglobulin E responses, and IL-1-receptor-deficient mice failed to induce iBALT formation. Therefore, the AM-IL-1α-iBALT axis might be a therapeutic target for particulate-induced allergic inflammation.


Asunto(s)
Bronquios/inmunología , Interleucina-1alfa/inmunología , Tejido Linfoide/inmunología , Macrófagos Alveolares/patología , Material Particulado/toxicidad , Compuestos de Aluminio/toxicidad , Animales , Femenino , Ratones , Ratones Endogámicos C57BL , Dióxido de Silicio/toxicidad
7.
EMBO Rep ; 24(12): e57485, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37870318

RESUMEN

Bacterial infections can activate and mobilize hematopoietic stem and progenitor cells (HSPCs) from the bone marrow (BM) to the spleen, a process termed extramedullary hematopoiesis (EMH). Recent studies suggest that commensal bacteria regulate not only the host immune system but also hematopoietic homeostasis. However, the impact of gut microbes on hematopoietic pathology remains unclear. Here, we find that systemic single injections of Akkermansia muciniphila (A. m.), a mucin-degrading bacterium, rapidly activate BM myelopoiesis and slow but long-lasting hepato-splenomegaly, characterized by the expansion and differentiation of functional HSPCs, which we term delayed EMH. Mechanistically, delayed EMH triggered by A. m. is mediated entirely by the MYD88/TRIF innate immune signaling pathway, which persistently stimulates splenic myeloid cells to secrete interleukin (IL)-1α, and in turn, activates IL-1 receptor (IL-1R)-expressing splenic HSPCs. Genetic deletion of Toll-like receptor-2 and -4 (TLR2/4) or IL-1α partially diminishes A. m.-induced delayed EMH, while inhibition of both pathways alleviates splenomegaly and EMH. Our results demonstrate that cooperative IL-1R- and TLR-mediated signals regulate commensal bacteria-driven EMH, which might be relevant for certain autoimmune disorders.


Asunto(s)
Hematopoyesis Extramedular , Humanos , Hematopoyesis Extramedular/genética , Esplenomegalia/metabolismo , Médula Ósea , Células Madre Hematopoyéticas/metabolismo , Hematopoyesis
8.
Biochem Biophys Res Commun ; 737: 150534, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39142137

RESUMEN

Pancreatic cancer is one of the most refractory malignancies. In situ vaccines (ISV), in which intratumorally injected immunostimulatory adjuvants activate innate immunity at the tumor site, utilize tumor-derived patient-specific antigens, thereby allowing for the development of vaccines in patients themselves. Near-infrared photoimmunotherapy (NIR-PIT) is a novel therapy that selectively kills cancer cells exclusively in the NIR-irradiated region. Extending our previous research showing that ISV using the unique nanoparticulate Toll-like receptor 9 (TLR9) ligand K3-SPG induced effective antitumor immunity, here we incorporated NIR-PIT into K3-SPG-ISV so that local tumor destruction by NIR-PIT augments the antitumor effect of ISV. In the mouse model of pancreatic cancer, the combination of K3-SPG-ISV and CD44-targeting NIR-PIT showed synergistic systemic antitumor effects and enhanced anti-programmed cell death-1 (PD-1) blockade. Mechanistically, strong intratumoral upregulation of interferon-related genes and dependency on CD8+ T cells were observed, suggesting the possible role of interferon and cytotoxic T cell responses in the induction of antitumor immunity. Importantly, this combination induced immunological memory in therapeutic and neoadjuvant settings. This study represents the first attempt to integrate NIR-PIT with ISV, offering a promising new direction for cancer immunotherapy, particularly for pancreatic cancer.

9.
J Immunol ; 207(11): 2720-2732, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34740961

RESUMEN

Double-positive CD4+CD8αß+ (DP) cells are thought to reside as T cell progenitors exclusively within the thymus. We recently discovered an unexpected CD4+ and CD8αß+ immune cell population in healthy and atherosclerotic mice by single-cell RNA sequencing. Transcriptomically, these cells resembled thymic DPs. Flow cytometry and three-dimensional whole-mount imaging confirmed DPs in thymus, mediastinal adipose tissue, and aortic adventitia, but nowhere else. Deep transcriptional profiling revealed differences between DP cells isolated from the three locations. All DPs were dependent on RAG2 expression and the presence of the thymus. Mediastinal adipose tissue DPs resided in close vicinity to invariant NKT cells, which they could activate in vitro. Thymus transplantation failed to reconstitute extrathymic DPs, and frequencies of extrathymic DPs were unaltered by pharmacologic inhibition of S1P1, suggesting that their migration may be locally confined. Our results define two new, transcriptionally distinct subsets of extrathymic DPs that may play a role in aortic vascular homeostasis.


Asunto(s)
Tejido Adiposo/inmunología , Aorta Torácica/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Timo/inmunología , Animales , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/inmunología , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células T Asesinas Naturales/inmunología
10.
Cell Mol Life Sci ; 80(1): 10, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36496494

RESUMEN

Atherosclerosis is initiated by subendothelial retention of lipoproteins and cholesterol, which triggers a non-resolving inflammatory process that over time leads to plaque progression in the artery wall. Myeloid cells and in particular macrophages are the primary drivers of the inflammatory response and plaque formation. Several immune cells including macrophages, T cells and B cells secrete the anti-inflammatory cytokine IL-10, known to be essential for the atherosclerosis protection. The cellular source of IL-10 in natural atherosclerosis progression is unknown. This study aimed to determine the main IL10-producing cell type in atherosclerosis. To do so, we crossed VertX mice, in which IRES-green fluorescent protein (eGFP) was placed downstream of exon 5 of the Il10 gene, with atherosclerosis-prone Apoe-/- mice. We found that myeloid cells express high levels of IL-10 in VertX Apoe-/- mice in both chow and western-diet fed mice. By single cell RNA sequencing and flow cytometry analysis, we identified resident and inflammatory macrophages in atherosclerotic plaques as the main IL-10 producers. To address whether IL-10 secreted by myeloid cells is essential for the protection, we utilized LyzMCre+Il10fl/fl mice crossed into the Apoe-/- background and confirmed that macrophages were unable to secrete IL-10. Chow and western diet-fed LyzMCre+Il10fl/fl Apoe-/- mice developed significantly larger atherosclerotic plaques as measured by en face morphometry than LyzMCre-Il10 fl/flApoe-/-. Flow cytometry and cytokine measurements suggest that the depletion of IL-10 in myeloid cells increases Th17 cells with elevated CCL2, and TNFα in blood plasma. We conclude that macrophage-derived IL-10 is critical for limiting atherosclerosis in mice.


Asunto(s)
Aterosclerosis , Interleucina-10 , Placa Aterosclerótica , Animales , Ratones , Aterosclerosis/genética , Aterosclerosis/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Interleucina-10/genética , Interleucina-10/metabolismo , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Placa Aterosclerótica/metabolismo , Ratones Noqueados para ApoE
11.
Circulation ; 142(13): 1279-1293, 2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-32703007

RESUMEN

BACKGROUND: Throughout the inflammatory response that accompanies atherosclerosis, autoreactive CD4+ T-helper cells accumulate in the atherosclerotic plaque. Apolipoprotein B100 (apoB), the core protein of low-density lipoprotein, is an autoantigen that drives the generation of pathogenic T-helper type 1 (TH1) cells with proinflammatory cytokine secretion. Clinical data suggest the existence of apoB-specific CD4+ T cells with an atheroprotective, regulatory T cell (Treg) phenotype in healthy individuals. Yet, the function of apoB-reactive Tregs and their relationship with pathogenic TH1 cells remain unknown. METHODS: To interrogate the function of autoreactive CD4+ T cells in atherosclerosis, we used a novel tetramer of major histocompatibility complex II to track T cells reactive to the mouse self-peptide apo B978-993 (apoB+) at the single-cell level. RESULTS: We found that apoB+ T cells build an oligoclonal population in lymph nodes of healthy mice that exhibit a Treg-like transcriptome, although only 21% of all apoB+ T cells expressed the Treg transcription factor FoxP3 (Forkhead Box P3) protein as detected by flow cytometry. In single-cell RNA sequencing, apoB+ T cells formed several clusters with mixed TH signatures that suggested overlapping multilineage phenotypes with pro- and anti-inflammatory transcripts of TH1, T helper cell type 2 (TH2), and T helper cell type 17 (TH17), and of follicular-helper T cells. ApoB+ T cells were increased in mice and humans with atherosclerosis and progressively converted into pathogenic TH1/TH17-like cells with proinflammatory properties and only a residual Treg transcriptome. Plaque T cells that expanded during progression of atherosclerosis consistently showed a mixed TH1/TH17 phenotype in single-cell RNA sequencing. In addition, we observed a loss of FoxP3 in a fraction of apoB+ Tregs in lineage tracing of hyperlipidemic Apoe-/- mice. In adoptive transfer experiments, converting apoB+ Tregs failed to protect from atherosclerosis. CONCLUSIONS: Our results demonstrate an unexpected mixed phenotype of apoB-reactive autoimmune T cells in atherosclerosis and suggest an initially protective autoimmune response against apoB with a progressive derangement in clinical disease. These findings identify apoB autoreactive Tregs as a novel cellular target in atherosclerosis.


Asunto(s)
Apolipoproteína B-100/inmunología , Aterosclerosis/inmunología , Autoinmunidad , Linfocitos T Reguladores/inmunología , Animales , Apolipoproteína B-100/genética , Aterosclerosis/genética , Ratones , Ratones Noqueados para ApoE , Linfocitos T Reguladores/patología
12.
Int Immunol ; 32(3): 203-212, 2020 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-31630209

RESUMEN

Influenza A virus (IAV) triggers the infected lung to produce IL-1 and recruit neutrophils. Unlike IL-1ß, however, little is known about IL-1α in terms of its mechanism of induction, action and physiological relevance to the host immunity against IAV infection. In particular, whether Z-DNA-binding protein 1 (ZBP1), a key molecule for IAV-induced cell death, is involved in the IL-1α induction, neutrophil infiltration and the physiological outcome has not been elucidated. Here, we show in a murine model that the IAV-induced IL-1α is mediated solely by ZBP1, in an NLRP3-inflammasome-independent manner, and is required for the optimal IL-1ß production followed by the formation of neutrophil extracellular traps (NETs). During IAV infection, ZBP1 displays a dual role in anti-IAV immune responses mediated by neutrophils, resulting in either protective or pathological outcomes in vivo. Thus, ZBP1-mediated IL-1α production is the key initial step of IAV-infected NETs, regulating the duality of the consequent lung inflammation.


Asunto(s)
Inflamasomas/inmunología , Inflamación/inmunología , Virus de la Influenza A/inmunología , Interleucina-1alfa/inmunología , Neutrófilos/inmunología , Proteínas de Unión al ARN/inmunología , Animales , Perros , Inflamación/metabolismo , Inflamación/patología , Interleucina-1alfa/metabolismo , Enfermedades Pulmonares/inmunología , Enfermedades Pulmonares/microbiología , Enfermedades Pulmonares/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/patología
13.
Eur J Immunol ; 49(9): 1433-1440, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31087643

RESUMEN

Adjuvants improve the potency of vaccines, but the modes of action (MOAs) of most adjuvants are largely unknown. TLR-dependent and -independent innate immune signaling through the adaptor molecule MyD88 has been shown to be pivotal to the effects of most adjuvants; however, MyD88's involvement in the TLR-independent MOAs of adjuvants is poorly understood. Here, using the T-dependent antigen NIPOVA and a unique particulate adjuvant called synthetic hemozoin (sHZ), we show that MyD88 is required for early GC formation and enhanced antibody class-switch recombination (CSR) in mice. Using cell-type-specific MyD88 KO mice, we found that IgG2c class switching, but not IgG1 class switching, was controlled by B cell-intrinsic MyD88 signaling. Notably, IFN-γ produced by various cells including T cells, NK cells, and dendritic cells was the primary cytokine for IgG2c CSR and B-cell intrinsic MyD88 is required for IFN-γ production. Moreover, IFN-γ receptor (IFNγR) deficiency abolished sHZ-induced IgG2c production, while recombinant IFN-γ administration successfully rescued IgG2c CSR impairment in mice lacking B-cell intrinsic MyD88. Together, our results show that B cell-intrinsic MyD88 signaling is involved in the MOA of certain particulate adjuvants and this may enhance our specific understanding of how adjuvants and vaccines work.


Asunto(s)
Linfocitos B/inmunología , Cambio de Clase de Inmunoglobulina/inmunología , Inmunoglobulina G/inmunología , Interferón gamma/inmunología , Factor 88 de Diferenciación Mieloide/inmunología , Transducción de Señal/inmunología , Adyuvantes Inmunológicos/farmacología , Animales , Células Dendríticas/inmunología , Células Asesinas Naturales/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Linfocitos T/inmunología
14.
Circ Res ; 122(12): 1675-1688, 2018 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-29545366

RESUMEN

RATIONALE: Atherosclerosis is a chronic inflammatory disease that is driven by the interplay of pro- and anti-inflammatory leukocytes in the aorta. Yet, the phenotypic and transcriptional diversity of aortic leukocytes is poorly understood. OBJECTIVE: We characterized leukocytes from healthy and atherosclerotic mouse aortas in-depth by single-cell RNA-sequencing and mass cytometry (cytometry by time of flight) to define an atlas of the immune cell landscape in atherosclerosis. METHODS AND RESULTS: Using single-cell RNA-sequencing of aortic leukocytes from chow diet- and Western diet-fed Apoe-/- and Ldlr-/- mice, we detected 11 principal leukocyte clusters with distinct phenotypic and spatial characteristics while the cellular repertoire in healthy aortas was less diverse. Gene set enrichment analysis on the single-cell level established that multiple pathways, such as for lipid metabolism, proliferation, and cytokine secretion, were confined to particular leukocyte clusters. Leukocyte populations were differentially regulated in atherosclerotic Apoe-/- and Ldlr-/- mice. We confirmed the phenotypic diversity of these clusters with a novel mass cytometry 35-marker panel with metal-labeled antibodies and conventional flow cytometry. Cell populations retrieved by these protein-based approaches were highly correlated to transcriptionally defined clusters. In an integrated screening strategy of single-cell RNA-sequencing, mass cytometry, and fluorescence-activated cell sorting, we detected 3 principal B-cell subsets with alterations in surface markers, functional pathways, and in vitro cytokine secretion. Leukocyte cluster gene signatures revealed leukocyte frequencies in 126 human plaques by a genetic deconvolution strategy. This approach revealed that human carotid plaques and microdissected mouse plaques were mostly populated by macrophages, T-cells, and monocytes. In addition, the frequency of genetically defined leukocyte populations in carotid plaques predicted cardiovascular events in patients. CONCLUSIONS: The definition of leukocyte diversity by high-dimensional analyses enables a fine-grained analysis of aortic leukocyte subsets, reveals new immunologic mechanisms and cell-type-specific pathways, and establishes a functional relevance for lesional leukocytes in human atherosclerosis.


Asunto(s)
Enfermedades de la Aorta/patología , Aterosclerosis/patología , Leucocitos/patología , Análisis de Secuencia de ARN/métodos , Animales , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Linfocitos B/patología , Citometría de Flujo/métodos , Humanos , Leucocitos/metabolismo , Macrófagos/patología , Ilustración Médica , Ratones , Monocitos/patología , Fenotipo , Receptores de LDL/deficiencia , Receptores de LDL/genética , Análisis de la Célula Individual/métodos , Linfocitos T/patología , Transcriptoma
15.
J Immunol ; 200(1): 71-81, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29150564

RESUMEN

Caspase recruitment domain family member 14 (CARD14) was recently identified as a psoriasis-susceptibility gene, but its immunological role in the pathogenesis of psoriasis in vivo remains unclear. In this study, we examined the role of CARD14 in murine experimental models of psoriasis induced by either imiquimod (IMQ) cream or recombinant IL-23 injection. In all models tested, the psoriasiform skin inflammation was abrogated in Card14-/- mice. Comparison of the early gene signature of the skin between IMQ-cream-treated Card14-/- mice and Tlr7-/-Tlr9-/- mice revealed not only their similarity, but also distinct gene sets targeted by IL-23. Cell type-specific analysis of these mice identified skin Langerinhigh Langerhans cells as a potent producer of IL-23, which was dependent on both TLR7 and TLR9 but independent of CARD14, suggesting that CARD14 is acting downstream of IL-23, not TLR7 or TLR9. Instead, a bone marrow chimera study suggested that CARD14 in radio-sensitive hematopoietic cells was required for IMQ-induced psoriasiform skin inflammation, controlling the number of Vγ4+ T cells producing IL-17 or IL-22 infiltrating through the dermis to the inflamed epidermis. These data indicate that CARD14 is essential and a potential therapeutic target for psoriasis.


Asunto(s)
Proteínas Adaptadoras de Señalización CARD/metabolismo , Guanilato-Quinasas/metabolismo , Células de Langerhans/inmunología , Psoriasis/inmunología , Piel/patología , Linfocitos T/inmunología , Aminoquinolinas/inmunología , Animales , Proteínas Adaptadoras de Señalización CARD/genética , Quimera , Guanilato-Quinasas/genética , Humanos , Imiquimod , Interleucina-17/metabolismo , Interleucina-23/inmunología , Interleucinas/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Animales , Terapia Molecular Dirigida , Psoriasis/inducido químicamente , Psoriasis/genética , Receptor Toll-Like 7/genética , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo , Transcriptoma , Interleucina-22
16.
J Immunol ; 200(6): 2067-2075, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29431693

RESUMEN

The priming, boosting, and restoration of memory cytotoxic CD8+ T lymphocytes by vaccination or immunotherapy in vivo is an area of active research. Particularly, nucleic acid-based compounds have attracted attention due to their ability to elicit strong Ag-specific CTL responses as a vaccine adjuvant. Nucleic acid-based compounds have been shown to act as anticancer monotherapeutic agents even without coadministration of cancer Ag(s); however, so far they have lacked efficacy in clinical trials. We recently developed a second-generation TLR9 agonist, a humanized CpG DNA (K3) complexed with schizophyllan (SPG), K3-SPG, a nonagonistic Dectin-1 ligand. K3-SPG was previously shown to act as a potent monoimmunotherapeutic agent against established tumors in mice in vivo. In this study we extend the monoimmunotherapeutic potential of K3-SPG to a nonhuman primate model. K3-SPG activated monkey plasmacytoid dendritic cells to produce both IFN-α and IL-12/23 p40 in vitro and in vivo. A single injection s.c. or i.v. with K3-SPG significantly increased the frequencies of activated memory CD8+ T cells in circulation, including Ag-specific memory CTLs, in cynomolgus macaques. This increase did not occur in macaques injected with free CpG K3 or polyinosinic-polycytidylic acid. Injection of 2 mg K3-SPG induced mild systemic inflammation, however, levels of proinflammatory serum cytokines and circulating neutrophil influx were lower than those induced by the same dose of polyinosinic-polycytidylic acid. Therefore, even in the absence of specific Ags, we show that K3-SPG has potent Ag-specific memory CTL response-boosting capabilities, highlighting its potential as a monoimmunotherapeutic agent for chronic infectious diseases and cancer.


Asunto(s)
Antígenos/inmunología , Linfocitos T CD8-positivos/inmunología , Células Dendríticas/inmunología , Memoria Inmunológica/inmunología , Animales , Citocinas/inmunología , Inmunoterapia/métodos , Inflamación/inmunología , Lectinas Tipo C/inmunología , Activación de Linfocitos/inmunología , Macaca fascicularis , Masculino , Neutrófilos/inmunología , Primates , Sizofirano/inmunología , Receptor Toll-Like 9/inmunología
17.
J Immunol ; 200(8): 2987-2999, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29555782

RESUMEN

Oncolytic reovirus, which possesses 10 segments of dsRNA genome, mediates antitumor effects via not only virus replication in a tumor cell-specific manner, but also activation of antitumor immunity; however, the mechanism(s) of reovirus-induced activation of antitumor immunity have not been fully elucidated. Recent studies have demonstrated that overcoming an immunosuppressive environment in tumor-bearing hosts is important to achieve efficient activation of antitumor immunity. Among the various types of cells involved in immunosuppression, it has been revealed that myeloid-derived suppressor cells (MDSCs) are significantly increased in tumor-bearing hosts and play crucial roles in the immunosuppression in tumor-bearing hosts. In this study, we examined whether reovirus inhibits the immunosuppressive activity of MDSCs, resulting in efficient activation of immune cells after in vivo administration. The results showed that splenic MDSCs recovered from PBS-treated tumor-bearing mice significantly suppressed the Ag-specific proliferation of CD8+ T cells. In contrast, the suppressive activity of MDSCs on T cell proliferation was significantly reduced after reovirus administration. Reovirus also inhibited the immunosuppressive activity of MDSCs in IFN-ß promoter stimulator-1 knockout (KO) mice and in wild-type mice. In contrast, the immunosuppressive activity of MDSCs in TLR-3 KO mice was not significantly altered by reovirus treatment. The activation levels of CD4+ and CD8+ T cells were significantly lower in TLR3 KO mice than in wild-type mice after reovirus administration. These results indicate that reovirus inhibits the immunosuppressive activity of MDSCs in a TLR3, but not IFN-ß promoter stimulator-1, signaling-dependent manner.


Asunto(s)
Células Supresoras de Origen Mieloide/inmunología , Neoplasias Experimentales/inmunología , Infecciones por Reoviridae/inmunología , Receptor Toll-Like 3/inmunología , Escape del Tumor/inmunología , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Virus Oncolíticos/inmunología
18.
Circulation ; 138(11): 1130-1143, 2018 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-29588316

RESUMEN

BACKGROUND: CD4+ T cells play an important role in atherosclerosis, but their antigen specificity is poorly understood. Immunization with apolipoprotein B (ApoB, core protein of low density lipoprotein) is known to be atheroprotective in animal models. Here, we report on a human APOB peptide, p18, that is sequence-identical in mouse ApoB and binds to both mouse and human major histocompatibility complex class II molecules. METHODS: We constructed p18 tetramers to detect human and mouse APOB-specific T cells and assayed their phenotype by flow cytometry including CD4 lineage transcription factors, intracellular cytokines, and T cell receptor activation. Apolipoprotein E-deficient ( Apoe-/-) mice were vaccinated with p18 peptide or adjuvants alone, and atherosclerotic burden in the aorta was determined. RESULTS: In human peripheral blood mononuclear cells from donors without cardiovascular disease, p18 specific CD4+ T cells detected by a new human leukocyte antigen-antigen D related-p18 tetramers were mostly Foxp3+ regulatory T cells (Tregs). Donors with subclinical cardiovascular disease as detected by carotid artery ultrasound had Tregs coexpressing retinoic acid-related orphan receptor gamma t or T-bet, which were both almost absent in donors without cardiovascular disease. In Apoe-/- mice, immunization with p18 induced Tregs and reduced atherosclerotic lesions. After peptide restimulation, responding CD4+ T cells identified by Nur77-GFP (green fluorescent protein) were highly enriched in Tregs. A new mouse I-Ab-p18 tetramer identified the expansion of p18-specific CD4+ T cells on vaccination, which were enriched for interleukin-10-producing Tregs. CONCLUSIONS: These findings show that APOB p18-specific CD4+ T cells are mainly Tregs in healthy donors, but coexpress other CD4 lineage transcription factors in donors with subclinical cardiovascular disease. This study identifies ApoB peptide 18 as the first Treg epitope in human and mouse atherosclerosis.


Asunto(s)
Apolipoproteína B-100/inmunología , Apolipoproteínas B/inmunología , Epítopos de Linfocito T/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Fragmentos de Péptidos/inmunología , Linfocitos T Reguladores/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Aorta/inmunología , Aorta/patología , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/inmunología , Enfermedades de la Aorta/patología , Enfermedades de la Aorta/prevención & control , Aterosclerosis/genética , Aterosclerosis/inmunología , Aterosclerosis/patología , Aterosclerosis/prevención & control , Modelos Animales de Enfermedad , Mapeo Epitopo , Femenino , Adyuvante de Freund/administración & dosificación , Humanos , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Fragmentos de Péptidos/administración & dosificación , Placa Aterosclerótica , Vacunación
19.
Eur J Immunol ; 48(9): 1580-1587, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29932463

RESUMEN

Vaccination with MHC-II-restricted peptides from Apolipoprotein B (ApoB) with complete and incomplete Freund's adjuvant (CFA/IFA) is known to protect mice from atherosclerosis. This vaccination induces antigen-specific IgG1 and IgG2c antibody responses and a robust CD4 T cell response in lymph nodes. However, CFA/IFA cannot be used in humans. To find a clinically applicable adjuvant, we tested the effect of vaccinating Apoe-deficient mice with ApoB peptide P6 (TGAYSNASSTESASY). In a broad screening experiment, Addavax, a squalene-based oil-in-water adjuvant similar to MF59, was the only adjuvant that showed similar efficacy as CFA/IFA. This was confirmed in a confirmation experiment for both the aortic arch and whole aorta analyzed by en face analysis after atherosclerotic lesion staining. Mechanistically, restimulated peritoneal cells from mice immunized with P6 in Addavax released significant amounts of IL-10. Unlike P6 in CFA/IFA, vaccination with P6 in Addavax did not induce any detectable IgG1 or IgG2c antibodies to P6. These data suggest that squalene-based adjuvants such as MF59 are good candidate adjuvants for developing a clinically effective atherosclerosis vaccine.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Apolipoproteínas B/inmunología , Aterosclerosis/prevención & control , Polisorbatos/farmacología , Escualeno/farmacología , Vacunas/inmunología , Animales , Apolipoproteínas B/administración & dosificación , Aterosclerosis/inmunología , Linfocitos T CD4-Positivos/inmunología , Femenino , Adyuvante de Freund/administración & dosificación , Adyuvante de Freund/inmunología , Inmunoglobulina G/inmunología , Lípidos/administración & dosificación , Lípidos/inmunología , Ratones , Ratones Noqueados , Vacunación
20.
J Immunol ; 198(12): 4707-4715, 2017 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-28507029

RESUMEN

DNA vaccines are attractive immunogens for priming humoral and cellular immune responses to the encoded Ag. However, their ability to induce Ag-specific CD8+ T cell responses requires improvement. Among the strategies for improving DNA vaccine immunogenicity are booster vaccinations, alternate vaccine formulations, electroporation, and genetic adjuvants, but few, such as extracellular vesicles (EVs), target natural Ag delivery systems. By focusing on CD63, a tetraspanin protein expressed on various cellular membranes, including EVs, we examined whether a DNA vaccine encoding an Ag fused to CD63 delivered into EVs would improve vaccine immunogenicity. In vitro transfection with plasmid DNA encoding an OVA Ag fused to CD63 (pCD63-OVA) produced OVA-carrying EVs. Immunizations with the purified OVA-carrying EVs primed naive mice to induce OVA-specific CD4+ and CD8+ T cells, whereas immunization with EVs purified from cells transfected with control plasmids encoding OVA protein alone or a calnexin-OVA fusion protein delivered into the endoplasmic reticulum failed to do so. Vaccinating mice with pCD63-OVA induced potent Ag-specific T cell responses, particularly those from CD8+ T cells. CD63 delivery into EVs led to better CD8+ T cell responses than calnexin delivery into the endoplasmic reticulum. When we used a mouse tumor implantation model to evaluate pCD63-OVA as a therapeutic vaccine, the EV-delivered DNA vaccination significantly inhibited tumor growth compared with the control DNA vaccinations. These results indicate that EV Ag delivery via DNA vaccination offers a new strategy for eliciting strong CD8+ T cell responses to the encoded Ag, making it a potentially useful cancer vaccine.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Vesículas Extracelulares/inmunología , Activación de Linfocitos , Tetraspanina 30/inmunología , Vacunas de ADN/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Presentación de Antígeno/inmunología , Linfocitos T CD4-Positivos/inmunología , Vacunas contra el Cáncer/inmunología , Femenino , Inmunidad Celular , Inmunización Secundaria , Inmunogenicidad Vacunal , Ratones , Ratones Endogámicos C57BL , Ovalbúmina/inmunología , Tetraspanina 30/genética , Vacunas de ADN/administración & dosificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA