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1.
Nat Commun ; 10(1): 4917, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664029

RESUMO

Assembly of soluble peptide-major histocompatibility complex class II (pMHCII) monomers into multimeric structures enables the detection of antigen-specific CD4+ T cells in biological samples and, in some configurations, their reprogramming in vivo. Unfortunately, current MHCII-αß chain heterodimerization strategies are typically associated with low production yields and require the use of foreign affinity tags for purification, precluding therapeutic applications in humans. Here, we show that fusion of peptide-tethered or empty MHCII-αß chains to the IgG1-Fc mutated to form knob-into-hole structures results in the assembly of highly stable pMHCII monomers. This design enables the expression and rapid purification of challenging pMHCII types at high yields without the need for leucine zippers and purification affinity tags. Importantly, this design increases the antigen-receptor signaling potency of multimerized derivatives useful for therapeutic applications and facilitates the detection and amplification of low-avidity T cell specificities in biological samples using flow cytometry.

2.
J Infect Chemother ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31607434

RESUMO

HIV-associated neurocognitive disorders (HAND) are characterized by cognitive, behavioral, and motor dysfunctions, which impact daily functioning and are predictive of poor survival among patients. The diagnosis of HAND is marked by clinically significant declines in multiple domains of neurocognitive functioning. Some patients diagnosed with HAND have social problem; however, higher brain dysfunction is not detected in general neuropsychological assessments and the intelligence quotient may remain unchanged. Impaired decision-making may reduce social and occupational qualities of life. The Iowa Gambling Task (IGT) has been developed as a task to evaluate risk predictions at the time of decision-making. In the present study, 38 HIV-infected patients enrolled in our hospital performed IGT and we investigated whether the results obtained are associated with HAND. The median net IGT score of all HIV-infected subjects was significantly lower than that of healthy controls. Patients diagnosed with HAND accounted for 43.8% of the negative net score group. We elucidated the relationship between the net IGT score and HAND for the first time. We think that IGT is a good tool to detect decision-making impairment for ANI and MND. Careful follow-ups of the progression of HAND and increased awareness among HIV-infected patients and medical care workers of the risk of social behavioral disorders, which negatively impact daily life before they are detected, are needed in order to prevent deteriorations in the quality of life of these patients.

3.
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
4.
Artigo em Inglês | MEDLINE | ID: mdl-30431449

RESUMO

: Inherited antithrombin (AT) deficiency is an autosomal dominant thrombotic disorder. We encountered a case of inherited type I AT deficiency and identified the causative mutation; a novel c.7430A>G missense mutation in the SERPINC1 gene in which tyrosine was substituted for cysteine at the 292nd amino acid. A recombinant AT protein with the 7430A>G mutation was not detected in cell lysates or culture supernatants. And then, our patient without personal or family history of thrombosis was pregnant woman with asymptomatic AT deficiency. Our patient treated with only AT concentrate therapy during pregnancy and she was able to safely give birth naturally and avoid thrombosis. We believe that this therapy for pregnant woman with asymptomatic AT deficiency is effective and safety as anticoagulant therapy during pregnancy.

5.
Intern Med ; 57(21): 3179-3182, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29877292

RESUMO

Mild hemophilia A is caused by a missense mutation in the FVIII gene that is responsible for a decrease in the FVIII:C to between 5% and 40%. The development of FVIII inhibitors has been reported in 3-13% of patients with mild hemophilia. Genetic risk factors for the development of inhibitors in mild hemophilia have been investigated. In the present study, we encountered a case of mild hemophilia with an FVIII inhibitor and identified the mutation responsible: a novel Phe595Cys mutation in the FVIII gene. In addition, this study showed that the inhibitor recognized exogenous wild-type FVIII and autologous mutant FVIII.

7.
Cell ; 171(3): 655-667.e17, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29053971

RESUMO

The gut microbiota contributes to the development of normal immunity but, when dysregulated, can promote autoimmunity through various non-antigen-specific effects on pathogenic and regulatory lymphocytes. Here, we show that an integrase expressed by several species of the gut microbial genus Bacteroides encodes a low-avidity mimotope of the pancreatic ß cell autoantigen islet-specific glucose-6-phosphatase-catalytic-subunit-related protein (IGRP206-214). Studies in germ-free mice monocolonized with integrase-competent, integrase-deficient, and integrase-transgenic Bacteroides demonstrate that the microbial epitope promotes the recruitment of diabetogenic CD8+ T cells to the gut. There, these effectors suppress colitis by targeting microbial antigen-loaded, antigen-presenting cells in an integrin ß7-, perforin-, and major histocompatibility complex class I-dependent manner. Like their murine counterparts, human peripheral blood T cells also recognize Bacteroides integrase. These data suggest that gut microbial antigen-specific cytotoxic T cells may have therapeutic value in inflammatory bowel disease and unearth molecular mimicry as a novel mechanism by which the gut microbiota can regulate normal immune homeostasis. PAPERCLIP.


Assuntos
Autoantígenos/imunologia , Bacteroides/imunologia , Colite/imunologia , Microbioma Gastrointestinal , Glucose-6-Fosfatase/imunologia , Adulto , Animais , Bacteroides/classificação , Bacteroides/enzimologia , Colite/microbiologia , Feminino , Glucose-6-Fosfatase/genética , Humanos , Tecido Linfoide/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Mimetismo Molecular , Linfócitos T/imunologia
8.
Nat Nanotechnol ; 12(7): 701-710, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28436959

RESUMO

We have shown that nanoparticles (NPs) can be used as ligand-multimerization platforms to activate specific cellular receptors in vivo. Nanoparticles coated with autoimmune disease-relevant peptide-major histocompatibility complexes (pMHC) blunted autoimmune responses by triggering the differentiation and expansion of antigen-specific regulatory T cells in vivo. Here, we define the engineering principles impacting biological activity, detail a synthesis process yielding safe and stable compounds, and visualize how these nanomedicines interact with cognate T cells. We find that the triggering properties of pMHC-NPs are a function of pMHC intermolecular distance and involve the sustained assembly of large antigen receptor microclusters on murine and human cognate T cells. These compounds show no off-target toxicity in zebrafish embryos, do not cause haematological, biochemical or histological abnormalities, and are rapidly captured by phagocytes or processed by the hepatobiliary system. This work lays the groundwork for the design of ligand-based NP formulations to re-program in vivo cellular responses using nanotechnology.

9.
Blood Coagul Fibrinolysis ; 28(2): 189-192, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26974330

RESUMO

Inherited antithrombin (AT) deficiency is an autosomal dominant thrombotic disorder. We encountered a case of inherited type I AT deficiency and identified the mutation responsible; a novel 5406delA mutation in the SERPINC1 gene appeared to have caused a frameshift with premature termination at amino acid +283. The recombinant AT protein including 5406delA was not detected in cell lysates or culture supernatants. These results will contribute to the creation of an accurate database and define the molecular basis for AT deficiency.


Assuntos
Deficiência de Antitrombina III/genética , Mutação da Fase de Leitura/genética , Adulto , Deficiência de Antitrombina III/sangue , Humanos , Masculino
10.
Case Rep Hematol ; 2016: 8751329, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27840748

RESUMO

The Janus kinase (JAK) 1 and 2 inhibitor, ruxolitinib, was recently approved in Japan and has been effective in many patients with myelofibrosis (MF). Although the inhibitor decreases splenomegaly and relieves MF-related symptoms, allogeneic hematopoietic cell transplantation (HCT) remains as the only curative therapy for MF. The presence of splenomegaly has been reported as a risk factor for graft failure, delayed engraftment, and poor survival. Here, we report two elderly MF patients with massive splenomegaly and a JAK2 V617F mutation. These patients underwent splenic irradiation to decrease splenomegaly prior to HCT with a reduced-intensity conditioning (RIC) regimen. Massive splenomegaly gradually decreased by 4 Gy splenic irradiation. The subsequent RIC regimen involved 4 Gy total body irradiation and fludarabine and intravenous busulfan. In both patients, engraftment failure did not occur, and complete remission was achieved. The splenomegaly decreased, and MF-related symptoms were resolved. Furthermore, the JAK2 V617F mutation disappeared, and fibrosis in the bone marrow regressed. We suggest that splenic irradiation prior to the RIC regimen for HCT in elderly MF patients with massive splenomegaly is safe. Furthermore, the HCT protocols with splenic irradiation should be considered for patients who have not shown clinical benefits to optimal medical management such as treatment with ruxolitinib.

11.
Intern Med ; 55(20): 3035-3038, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27746445

RESUMO

Vancomycin-induced thrombocytopenia is a rare adverse reaction that may be overlooked because no specific diagnostic test is currently available. We herein report a patient with vancomycin-induced immune thrombocytopenia who was diagnosed by the detection of vancomycin-dependent anti-platelet antibody with flow cytometry. An IgG antibody in the patient's serum reacted with platelets only in the presence of vancomycin. Severe thrombocytopenia gave rise to life-threatening gastrointestinal bleeding, which was quickly resolved after effective platelet transfusion following the cessation of vancomycin administration. This report suggests that the flow cytometric test is useful for the differential diagnosis of thrombocytopenia and platelet transfusion should be performed after the cessation of vancomycin administration.


Assuntos
Antibacterianos/efeitos adversos , Púrpura Trombocitopênica Idiopática/induzido quimicamente , Púrpura Trombocitopênica Idiopática/diagnóstico , Vancomicina/efeitos adversos , Idoso , Antibacterianos/imunologia , Plaquetas/imunologia , Feminino , Citometria de Fluxo , Humanos , Imunoglobulina G/sangue , Transfusão de Plaquetas , Púrpura Trombocitopênica Idiopática/terapia , Vancomicina/imunologia
12.
Nat Commun ; 7: 13027, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27708334

RESUMO

Type 1 diabetes (T1D) is characterized by a chronic, progressive autoimmune attack against pancreas-specific antigens, effecting the destruction of insulin-producing ß-cells. Here we show interleukin-2 (IL-2) is a non-pancreatic autoimmune target in T1D. Anti-IL-2 autoantibodies, as well as T cells specific for a single orthologous epitope of IL-2, are present in the peripheral blood of non-obese diabetic (NOD) mice and patients with T1D. In NOD mice, the generation of anti-IL-2 autoantibodies is genetically determined and their titre increases with age and disease onset. In T1D patients, circulating IgG memory B cells specific for IL-2 or insulin are present at similar frequencies. Anti-IL-2 autoantibodies cloned from T1D patients demonstrate clonality, a high degree of somatic hypermutation and nanomolar affinities, indicating a germinal centre origin and underscoring the synergy between cognate autoreactive T and B cells leading to defective immune tolerance.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Tolerância Imunológica , Interleucina-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Autoanticorpos/imunologia , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Pessoa de Meia-Idade , Pâncreas/imunologia , Peptídeos/imunologia , Linfócitos T/citologia , Adulto Jovem
13.
Rinsho Ketsueki ; 57(7): 869-72, 2016 07.
Artigo em Japonês | MEDLINE | ID: mdl-27498731

RESUMO

An 81-year-old man presenting with fever, neurological symptoms, thrombocytopenia, and hemolytic anemia was diagnosed with acquired idiopathic thrombotic thrombocytopenic purpura (TTP). His disintegrin-like and metalloproteinase with thrombospondin type 1 motifs 13 (ADAMTS13) activity was <1% and the ADAMTS13 inhibitor titer was 3.2 BU/ml. He received plasma exchange and steroid administration until remission was achieved. Seven months later, he suffered from paralysis of the right hand, hemolytic anemia, and thrombocytopenia. We confirmed TTP recurrence based on ADAMTS13 activity <1% and an ADAMTS13 inhibitor titer of 19.4 BU/ml. Four infusions of rituximab were administered in addition to plasma exchange and steroid pulse therapy. Platelet count recovery was observed within 5 days. No severe side effects related to rituximab occurred. Although rituximab has not been approved for TTP in Japan, we report the efficacy and safety of rituximab in an elderly patient with recurrent TTP. We suggest that rituximab therapy should be started as soon as possible for recurrent TTP in patients with high titers of ADAMTS13 inhibitor.


Assuntos
Antineoplásicos/uso terapêutico , Púrpura Trombocitopênica Trombótica/tratamento farmacológico , Rituximab/uso terapêutico , Idoso de 80 Anos ou mais , Humanos , Masculino , Troca Plasmática , Púrpura Trombocitopênica Trombótica/terapia , Recidiva , Indução de Remissão
14.
Nature ; 530(7591): 434-40, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26886799

RESUMO

Regulatory T cells hold promise as targets for therapeutic intervention in autoimmunity, but approaches capable of expanding antigen-specific regulatory T cells in vivo are currently not available. Here we show that systemic delivery of nanoparticles coated with autoimmune-disease-relevant peptides bound to major histocompatibility complex class II (pMHCII) molecules triggers the generation and expansion of antigen-specific regulatory CD4(+) T cell type 1 (TR1)-like cells in different mouse models, including mice humanized with lymphocytes from patients, leading to resolution of established autoimmune phenomena. Ten pMHCII-based nanomedicines show similar biological effects, regardless of genetic background, prevalence of the cognate T-cell population or MHC restriction. These nanomedicines promote the differentiation of disease-primed autoreactive T cells into TR1-like cells, which in turn suppress autoantigen-loaded antigen-presenting cells and drive the differentiation of cognate B cells into disease-suppressing regulatory B cells, without compromising systemic immunity. pMHCII-based nanomedicines thus represent a new class of drugs, potentially useful for treating a broad spectrum of autoimmune conditions in a disease-specific manner.


Assuntos
Autoantígenos/imunologia , Autoimunidade/imunologia , Linfócitos T Reguladores/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Antígenos CD11/imunologia , Diferenciação Celular , Citocinas/imunologia , Feminino , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Nanomedicina , Nanopartículas/química , Nanopartículas/uso terapêutico , Especificidade de Órgãos , Prevalência , Solubilidade , Linfócitos T Reguladores/citologia
16.
J Immunol ; 193(7): 3296-307, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25165150

RESUMO

We investigated whether a prevalent epitope of the ß-cell-specific autoantigen islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP206-214) reaches regional Ag-presentation pathways via unprocessed polypeptide chains, as free IGRP206-214 peptide or via preformed IGRP206-214/K(d) complexes. This was accomplished by expressing bacterial artificial chromosome transgenes encoding wild-type (stable) or ubiquitinated (unstable) forms of IGRP in IGRP-deficient NOD mice carrying MHC class I-deficient ß-cells, dendritic cells, or B cells. We investigated the ability of the pancreatic lymph nodes of these mice to prime naive IGRP206-214-reactive CD8(+) T cells in vivo, either in response to spontaneous Ag shedding, or to synchronized forms of ß-cell necrosis or apoptosis. When IGRP was made unstable by targeting it for proteasomal degradation within ß-cells, the cross-priming, autoimmune-initiating potential of this autoantigen (designated autoantigenicity) was impaired. Yet at the same time, the direct presentation, CTL-targeting potential of IGRP (designated pathogenicity) was enhanced. The appearance of IGRP206-214 in regional Ag-presentation pathways was dissociated from transfer of IGRP206-214 or IGRP206-214/K(d) from ß cells to dendritic cells. These results indicate that autoantigenicity and pathogenicity are separable and inversely related properties and suggest that pathogenic autoantigens, capable of efficiently priming CTLs while marking target cells for CTL-induced killing, may have a critical balance of these two properties.


Assuntos
Apresentação do Antígeno , Autoantígenos/imunologia , Apresentação Cruzada , Células Dendríticas/imunologia , Glucose-6-Fosfatase/imunologia , Células Secretoras de Insulina/imunologia , Animais , Apoptose/imunologia , Autoantígenos/genética , Linfócitos B/imunologia , Linfócitos B/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Células Dendríticas/patologia , Glucose-6-Fosfatase/genética , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Células Secretoras de Insulina/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Necrose
17.
PLoS One ; 9(3): e92848, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24676388

RESUMO

Zinc finger protein 521 (ZFP521) regulates a number of cellular processes in a wide range of tissues, such as osteoblast formation and adipose commitment and differentiation. In the field of neurobiology, it is reported to be an essential factor for transition of epiblast stem cells into neural progenitors in vitro. However, the role of ZFP521 in the brain in vivo still remains elusive. To elucidate the role of ZFP521 in the mouse brain, we generated mice lacking exon 4 of the ZFP521 gene. The birth ratio of our ZFP521Δ/Δ mice was consistent with Mendel's laws. Although ZFP521Δ/Δ pups had no apparent defect in the body and were indistinguishable from ZFP521+/+ and ZFP521+/Δ littermates at the time of birth, ZFP521Δ/Δ mice displayed significant weight reduction as they grew, and most of them died before 10 weeks of age. They displayed abnormal behavior, such as hyper-locomotion, lower anxiety and impaired learning, which correspond to the symptoms of schizophrenia. The border of the granular cell layer of the dentate gyrus in the hippocampus of the mice was indistinct and granular neurons were reduced in number. Furthermore, Sox1-positive neural progenitor cells in the dentate gyrus and cerebellum were significantly reduced in number. Taken together, these findings indicate that ZFP521 directly or indirectly affects the formation of the neuronal cell layers of the dentate gyrus in the hippocampus, and thus ZFP521Δ/Δ mice displayed schizophrenia-relevant symptoms. ZFP521Δ/Δ mice may be a useful research tool as an animal model of schizophrenia.


Assuntos
Comportamento Animal , Hipocampo/metabolismo , Deficiência Intelectual/genética , Mutação , Fatores de Transcrição/genética , Animais , Giro Denteado/metabolismo , Modelos Animais de Doenças , Éxons , Feminino , Ordem dos Genes , Marcação de Genes , Estudos de Associação Genética , Loci Gênicos , Genótipo , Hipocampo/patologia , Imuno-Histoquímica , Expectativa de Vida , Masculino , Camundongos , Células-Tronco Neurais/citologia , Fenótipo
20.
Int J Clin Oncol ; 19(1): 178-85, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23380958

RESUMO

BACKGROUND: Febrile neutropenia (FN) is one of the serious complications of chemotherapy. However, the hematological nadir after chemotherapy and the timing of prophylaxis for FN remain unclear, especially for outpatients. METHODS: We prospectively analyzed laboratory data from outpatients treated with a single chemotherapy regimen, rituximab (R)-CHOP, on three consultation days (days 8, 10, and 15) after chemotherapy to identify any factors that might predict the onset of the hematological nadir and the optimal timing of G-CSF prophylaxis. RESULTS: A total of 100 courses of chemotherapy (total 33 patients) were analyzed. Onset of the hematological nadir was not predictable in any of the patients who had a white blood cell count (WBC) of >5,500 × 10(6)/L and/or monocyte count of >80 × 10(6)/L on day 8, and thus there was little opportunity for G-CSF prophylaxis in each treatment course. Among patients who had a WBC count of 1,500-5,500 × 10(6)/L on day 8, the monocyte count on day 8 was significantly associated with the hematological nadir. Patients who had a monocyte count of <5 × 10(6)/L on day 8, were identified as a high-risk group for neutropenia for whom G-CSF administration during the current treatment course should be considered. CONCLUSION: Our results indicate that, in outpatients receiving R-CHOP chemotherapy, the monocyte count on day 8 is a useful marker of the hematological nadir, allowing an opportunity for G-CSF prophylaxis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Linfoma não Hodgkin/tratamento farmacológico , Neutropenia/induzido quimicamente , Adulto , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Neutropenia/patologia , Prednisona/administração & dosagem , Vincristina/administração & dosagem
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