Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Nat Commun ; 15(1): 899, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321013

RESUMO

Antigen-specific regulatory T cells (Tregs) suppress pathogenic autoreactivity and are potential therapeutic candidates for autoimmune diseases such as systemic lupus erythematosus (SLE). Lupus nephritis is associated with autoreactivity to the Smith (Sm) autoantigen and the human leucocyte antigen (HLA)-DR15 haplotype; hence, we investigated the potential of Sm-specific Tregs (Sm-Tregs) to suppress disease. Here we identify a HLA-DR15 restricted immunodominant Sm T cell epitope using biophysical affinity binding assays, then identify high-affinity Sm-specific T cell receptors (TCRs) using high-throughput single-cell sequencing. Using lentiviral vectors, we transduce our lead Sm-specific TCR into Tregs derived from patients with SLE who are anti-Sm and HLA-DR15 positive. Compared with polyclonal mock-transduced Tregs, Sm-Tregs potently suppress Sm-specific pro-inflammatory responses in vitro and suppress disease progression in a humanized mouse model of lupus nephritis. These results show that Sm-Tregs are a promising therapy for SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Camundongos , Animais , Humanos , Linfócitos T Reguladores , Autoantígenos/metabolismo
2.
Front Immunol ; 13: 821595, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154139

RESUMO

Heterologous immunity, when the memory T cell response elicited by one pathogen recognizes another pathogen, has been offered as a contributing factor for the high variability in coronavirus disease 2019 (COVID-19) severity outcomes. Here we demonstrate that sensitization with bacterial peptides can induce heterologous immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) derived peptides and that vaccination with the SARS-CoV-2 spike protein can induce heterologous immunity to bacterial peptides. Using in silico prediction methods, we identified 6 bacterial peptides with sequence homology to either the spike protein or non-structural protein 3 (NSP3) of SARS-CoV-2. Notwithstanding the effects of bystander activation, in vitro co-cultures showed that all individuals tested (n=18) developed heterologous immunity to SARS-CoV-2 peptides when sensitized with the identified bacterial peptides. T cell recall responses measured included cytokine production (IFN-γ, TNF, IL-2), activation (CD69) and proliferation (CellTrace). As an extension of the principle of heterologous immunity between bacterial pathogens and COVID-19, we tracked donor responses before and after SARS-CoV-2 vaccination and measured the cross-reactive T cell responses to bacterial peptides with similar sequence homology to the spike protein. We found that SARS-CoV-2 vaccination could induce heterologous immunity to bacterial peptides. These findings provide a mechanism for heterologous T cell immunity between common bacterial pathogens and SARS-CoV-2, which may explain the high variance in COVID-19 outcomes from asymptomatic to severe. We also demonstrate proof-of-concept that SARS-CoV-2 vaccination can induce heterologous immunity to pathogenic bacteria derived peptides.


Assuntos
Infecções Bacterianas/imunologia , COVID-19/imunologia , Imunidade Heteróloga/imunologia , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Adulto , Vacinas contra COVID-19/imunologia , Células Cultivadas , Técnicas de Cocultura , Feminino , Humanos , Imunidade Celular/imunologia , Masculino , Glicoproteína da Espícula de Coronavírus/imunologia
3.
Lancet Rheumatol ; 4(12): e822-e830, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38261390

RESUMO

BACKGROUND: Treat-to-target goals for patients with systemic lupus erythematosus (SLE) have been validated to protect against organ damage and to improve quality of life. We aimed to investigate the association between lupus low disease activity state (LLDAS) and remission and risk of mortality in patients with SLE. We hypothesised that LLDAS has a protective association with mortality risk. METHODS: In this prospective, multinational, longitudinal cohort study, we used data from patients with SLE in the Asia Pacific Lupus Collaboration cohort collected between May 1, 2013, and Dec 31, 2020. Eligible patients were adults (aged ≥18 years) who met either the 1997 American College of Rheumatology modified classification criteria for SLE or the 2012 Systemic Lupus International Collaborating Clinics classification criteria. The primary outcome was all-cause mortality, and LLDAS, remission, and variations of remission with lower glucocorticoid thresholds were the primary exposure variables. Survival analyses were used to examine longitudinal associations between these endpoints and risk of mortality. This study is registered with ClinicalTrials.gov, NCT03138941. FINDINGS: Among a total of 4106 patients in the cohort, 3811 (92·8%) patients were included in the final analysis (median follow-up 2·8 years [IQR 1·0-5·3]; 3509 [92·1%] women and 302 [7·9%] men), of whom 80 died during the observation period (crude mortality rate 6·4 deaths per 1000 person-years). LLDAS was attained at least once in 43 (53·8%) of 80 participants who died and in 3035 (81·3%) of 3731 participants who were alive at the end of the study (p<0·0001); 22 (27·5%) participants who died versus 1966 (52·7%) who were alive at the end of the study attained LLDAS for at least 50% of observed time (p<0·0001). Remission was attained by 32 (40·0%) of 80 who died and in 2403 (64·4%) of 3731 participants who were alive at the end of the study (p<0·0001); 14 (17·5%) participants who died versus 1389 (37·2%) who were alive at the end of the study attained remission for at least 50% of observed time (p<0·0001). LLDAS for at least 50% of observed time (adjusted hazard ratio 0·51 [95% CI 0·31-0·85]; p=0·010) and remission for at least 50% of observed time (0·52 [0·29-0·93]; p=0·027) were associated with reduced risk of mortality. Modifying the remission glucocorticoid threshold (<5·0 mg/day prednisolone) was more protective against mortality than current remission definitions (0·31 [0·12-0·77]; p=0·012), and glucocorticoid-free remission was the most protective (0·13 [0·02-0·96]; p=0·046). INTERPRETATION: LLDAS significantly reduced the risk of mortality in patients with SLE. Remission did not further reduce the risk of mortality compared with LLDAS, unless lower glucocorticoid thresholds were used. FUNDING: The Asia-Pacific Lupus Collaboration received funding from Janssen, Bristol Myers Squibb, Eli Lilly, and UCB for this study.


Assuntos
Glucocorticoides , Lúpus Eritematoso Sistêmico , Adulto , Masculino , Humanos , Feminino , Adolescente , Estudos Longitudinais , Estudos Prospectivos , Qualidade de Vida
5.
J Child Adolesc Psychopharmacol ; 23(3): 179-93, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23560600

RESUMO

OBJECTIVE: The purpose of this article was to systematically review the literature on stimulant and atomoxetine combination therapy, in particular: 1) Characteristics of patients with attention-deficit/hyperactivity disorder (ADHD) given combination therapy, 2) treatment strategies used, 3) efficacy and effectiveness, and 4) safety and tolerability. METHODS: Literature databases (MEDLINE(®), EMBASE, Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, and SciVerse Scopus) were systematically searched using prespecified criteria. Publications describing stimulant and atomoxetine combination therapy in patients with ADHD or healthy volunteers were selected for review. Exclusion criteria were comorbid psychosis, bipolar disorder, epilepsy, or other psychiatric/neurologic diseases that could confound ADHD symptom assessment, or other concomitant medication(s) to treat ADHD symptoms. RESULTS: Of the 16 publications included for review, 14 reported findings from 3 prospective studies (4 publications), 7 retrospective studies, and 3 narrative reviews/medication algorithms of patients with ADHD. The other two publications reported findings from two prospective studies of healthy volunteers. The main reason for prescribing combination therapy was inadequate response to previous treatment. In the studies of patients with ADHD, if reported, 1) most patients were children/adolescents and male, and had a combined ADHD subtype; 2) methylphenidate was most often used in combination with atomoxetine for treatment augmentation or switch; 3) ADHD symptom control was improved in some, but not all, patients; and 4) there were no serious adverse events. CONCLUSIONS: Published evidence of the off-label use of stimulant and atomoxetine combination therapy is limited because of the small number of publications, heterogeneous study designs (there was only one prospective, randomized controlled trial), small sample sizes, and geographic bias. Existing evidence suggests, but does not confirm, that this drug combination may benefit some, but not all, patients who have tried several ADHD medications without success.


Assuntos
Inibidores da Captação Adrenérgica/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Propilaminas/uso terapêutico , Inibidores da Captação Adrenérgica/administração & dosagem , Inibidores da Captação Adrenérgica/efeitos adversos , Cloridrato de Atomoxetina , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/efeitos adversos , Criança , Quimioterapia Combinada , Humanos , Propilaminas/administração & dosagem , Propilaminas/efeitos adversos , Resultado do Tratamento
6.
Am J Physiol Endocrinol Metab ; 304(1): E23-31, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23092911

RESUMO

Thyroid hormones (THs) are vital for normal postnatal development. Extracellular TH distributor proteins create an intravascular reservoir of THs. Transthyretin (TTR) is a TH distributor protein in the circulatory system and is the only TH distributor protein synthesized in the central nervous system. We investigated the phenotype of TTR null mice during development. Total and free 3',5',3,5-tetraiodo-L-thyronine (T(4)) and free 3',3,5-triiodo-L-thyronine (T(3)) in plasma were significantly reduced in 14-day-old (P14) TTR null mice. TTR null mice also displayed a delayed suckling-to-weaning transition, decreased muscle mass, delayed growth, and retarded longitudinal bone growth. In addition, ileums from postnatal day 0 (P0) TTR null mice displayed disordered architecture and contained fewer goblet cells than wild type. Protein concentrations in cerebrospinal fluid from P0 and P14 TTR null mice were higher than in age-matched wild-type mice. In contrast to the current literature based on analyses of adult TTR null mice, our results demonstrate that TTR has an important and nonredundant role in influencing the development of several organs.


Assuntos
Transtornos do Crescimento/genética , Crescimento e Desenvolvimento/efeitos dos fármacos , Pré-Albumina/genética , Hormônios Tireóideos/farmacologia , Animais , Análise Química do Sangue , Glicemia/metabolismo , Transtornos do Crescimento/sangue , Transtornos do Crescimento/metabolismo , Crescimento e Desenvolvimento/fisiologia , Camundongos , Camundongos Knockout , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Pré-Albumina/metabolismo , Pré-Albumina/fisiologia , Testes de Função Tireóidea , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Ureia/sangue
7.
Curr Med Res Opin ; 28(10): 1575-83, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22978774

RESUMO

OBJECTIVES: To investigate whether plagiarism is more prevalent in publications retracted from the medical literature when first authors are affiliated with lower-income countries versus higher-income countries. Secondary objectives included investigating other factors associated with plagiarism (e.g., national language of the first author's country affiliation, publication type, journal ranking). DESIGN: Systematic, controlled, retrospective, bibliometric study. DATA SOURCE: Retracted publications dataset in MEDLINE (search filters: English, human, January 1966-February 2008). DATA SELECTION: Retracted misconduct publications were classified according to the first author's country affiliation, country income level, and country national language, publication type, and ranking of the publishing journal. Standardised definitions and data collection tools were used; data were analysed (odds ratio [OR], 95% confidence limits [CL], chi-squared tests) by an independent academic statistician. RESULTS: Of the 213 retracted misconduct publications, 41.8% (89/213) were retracted for plagiarism, 52.1% (111/213) for falsification/fabrication, 2.3% (5/213) for author disputes, 2.3% (5/213) for ethical issues, and 1.4% (3/213) for unknown reasons. The OR (95% CL) of plagiarism retractions (other misconduct retractions as reference) were higher (P < 0.001) for first authors affiliated with lower-income versus higher-income countries (15.4 [4.5, 52.9]) and with non-English versus English national language countries (3.2 [1.8, 5.7]), for non-original research versus original research publications (8.4 [3.3, 21.3]), for case reports and series versus other original research types (4.2 [1.4, 13.0]), and for publications in low-ranked versus high-ranked journals (4.9 [2.4, 9.9]). Up until 2012, there were significantly (P < 0.007) fewer 'serial offenders' (first authors with >1 retraction) with publications retracted for plagiarism (11.5%, 9/78) than other types of misconduct (28.9%, 24/83). CONCLUSIONS: This is the first study to demonstrate that publications retracted for plagiarism are significantly associated with first authors affiliated with lower-income countries. These findings have implications for developing appropriate evidence-based strategies and allocation of resources to help mitigate plagiarism misconduct.


Assuntos
Pesquisa Biomédica/ética , Publicações Periódicas como Assunto , Plágio , Retratação de Publicação como Assunto , Má Conduta Científica/ética , Humanos , MEDLINE
8.
Curr Med Res Opin ; 27(6): 1175-82, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21473670

RESUMO

OBJECTIVES: The primary objective of this study was to quantify how many publications retracted because of misconduct involved declared medical writers (i.e., not ghostwriters) or declared pharmaceutical industry support. The secondary objective was to investigate factors associated with misconduct retractions. DESIGN: A systematic, controlled, retrospective, bibliometric study. DATA SOURCE: Retracted publications dataset in the MEDLINE database. DATA SELECTION: PubMed was searched (Limits: English, human, January 1966 - February 2008) to identify publications retracted because of misconduct. Publications retracted because of mistake served as the control group. Standardized definitions and data collection tools were used, and data were analyzed by an independent academic statistician. RESULTS: Of the 463 retracted publications retrieved, 213 (46%) were retracted because of misconduct. Publications retracted because of misconduct rarely involved declared medical writers (3/213; 1.4%) or declared pharmaceutical industry support (8/213; 3.8%); no misconduct retractions involved both declared medical writers and the industry. Retraction because of misconduct, rather than mistake, was significantly associated with: absence of declared medical writers (odds ratio: 0.16; 95% confidence interval: 0.05-0.57); absence of declared industry involvement (0.25; 0.11-0.58); single authorship (2.04; 1.01-4.12); first author having at least one other retraction (2.05; 1.35-3.11); and first author affiliated with a low/middle income country (2.34; 1.18-4.63). The main limitations of this study were restricting the search to English-language and human research articles. CONCLUSIONS: Publications retracted because of misconduct rarely involved declared medical writers or declared pharmaceutical industry support. Increased attention should focus on factors that are associated with misconduct retractions.


Assuntos
Indústria Farmacêutica , Jornalismo Médico , Editoração , Má Conduta Científica , Bibliometria , Humanos , Estudos Retrospectivos
9.
Am J Physiol Regul Integr Comp Physiol ; 288(5): R1264-72, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15650116

RESUMO

Thyroid hormones are essential for vertebrate development. There is a characteristic rise in thyroid hormone levels in blood during critical periods of thyroid hormone-regulated development. Thyroid hormones are lipophilic compounds, which readily partition from an aqueous environment into a lipid environment. Thyroid hormone distributor proteins are required to ensure adequate distribution of thyroid hormones, throughout the aqueous environment of the blood, and to counteract the avid partitioning of thyroid hormones into the lipid environment of cell membranes. In human blood, these proteins are albumin, transthyretin and thyroxine-binding globulin. We analyzed the developmental profile of thyroid hormone distributor proteins in serum from a representative of each order of marsupials (M. eugenii; S.crassicaudata), a reptile (C. porosus), in two species of salmonoid fishes (S. salar; O. tshawytsch), and throughout a calendar year for sea bream (S. aurata). We demonstrated that during development, these animals have a thyroid hormone distributor protein present in their blood which is not present in the adult blood. At least in mammals, this additional protein has higher affinity for thyroid hormones than the thyroid hormone distributor proteins in the blood of the adult. In fish, reptile and polyprotodont marsupial, this protein was transthyretin. In a diprotodont marsupial, it was thyroxine-binding globulin. We propose an hypothesis that an augmented thyroid hormone distributor protein network contributes to the rise in total thyroid hormone levels in the blood during development.


Assuntos
Jacarés e Crocodilos/metabolismo , Proteínas de Transporte/sangue , Peixes/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Marsupiais/metabolismo , Hormônios Tireóideos/metabolismo , Jacarés e Crocodilos/crescimento & desenvolvimento , Animais , Peixes/crescimento & desenvolvimento , Marsupiais/crescimento & desenvolvimento , Pré-Albumina/metabolismo , Albumina Sérica/metabolismo , Proteínas de Ligação a Tiroxina/metabolismo
10.
J Immunol ; 173(6): 3816-24, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15356129

RESUMO

Glucocorticoid (GC) hormones cause pronounced T cell apoptosis, particularly in immature thymic T cells. This is possibly due to tissue-specific regulation of the glucocorticoid receptor (GR) gene. In mice the GR gene is transcribed from five separate promoters designated: 1A, 1B, 1C, 1D, and 1E. Nearly all cells express GR from promoters 1B-1E, but the activity of the 1A promoter has only been reported in the whole thymus or lymphocyte cell lines. To directly assess the role of GR promoter use in sensitivity to glucocorticoid-induced cell death, we have compared the activity of the GR 1A promoter with GC sensitivity in different mouse lymphocyte populations. We report that GR 1A promoter activity is restricted to thymocyte and peripheral lymphocyte populations and the cortex of the brain. The relative level of expression of the 1A promoter to the 1B-1E promoters within a lymphocyte population was found to directly correlate with susceptibility to GC-induced cell death, with the extremely GC-sensitive CD4+CD8+ thymocytes having the highest levels of GR 1A promoter activity, and the relatively GC-resistant alphabetaTCR+CD24(int/low) thymocytes and peripheral T cells having the lowest levels. DNA sequencing of the mouse GR 1A promoter revealed a putative glucocorticoid-response element. Furthermore, GR 1A promoter use and GR protein levels were increased by GC treatment in thymocytes, but not in splenocytes. These data suggest that tissue-specific differences in GR promoter use determine T cell sensitivity to glucocorticoid-induced cell death.


Assuntos
Glucocorticoides/fisiologia , Regiões Promotoras Genéticas/imunologia , Receptores de Glucocorticoides/biossíntese , Receptores de Glucocorticoides/genética , Linfócitos T/citologia , Linfócitos T/imunologia , Animais , Sequência de Bases , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Morte Celular/imunologia , Diferenciação Celular/imunologia , Sobrevivência Celular/imunologia , Células Cultivadas , Córtex Cerebral/imunologia , Córtex Cerebral/metabolismo , Dexametasona/metabolismo , Dexametasona/farmacologia , Relação Dose-Resposta Imunológica , Glucocorticoides/metabolismo , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , RNA Mensageiro/biossíntese , Elementos de Resposta/imunologia , Análise de Sequência de DNA , Baço/citologia , Baço/imunologia , Baço/metabolismo , Linfócitos T/metabolismo , Regulação para Cima/genética , Regulação para Cima/imunologia
11.
Am J Respir Cell Mol Biol ; 30(5): 613-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14578211

RESUMO

Glucocorticoids provide important signals for maturation of the fetal lung and antenatal glucocorticoids are used to reduce the respiratory insufficiency suffered by preterm infants. To further understand the role of glucocorticoids in fetal lung maturation, we have analyzed mice with a targeted null mutation for the glucocorticoid receptor (GR) gene, which severely retards lung development. The lungs of fetal GR-null mice have increased lung weight and DNA content, are condensed and hypercellular, with reduced septal thinning leading to a 6-fold increase in the airway to capillary diffusion distance. In fetal GR-null mice, mRNA levels of the type II epithelial cell surfactant protein genes A and C were reduced by approximately 50%. Analysis of epithelial cell types by electron microscopy revealed that the proportions of type II cells were increased by approximately 30%, whereas the proportions of type-I cells were markedly reduced (by approximately 50%). Similarly, we found a 50% reduction in mRNA levels for T1alpha and aquaporin-5, two type I cell-specific markers, and a 20% reduction in aquaporin-1 mRNA levels. This demonstrates that during murine embryonic development, receptor-mediated glucocorticoid signaling facilitates the differentiation of epithelial cells into type I cells, but is not obligatory for type II cell differentiation.


Assuntos
Embrião de Mamíferos/anatomia & histologia , Células Epiteliais/metabolismo , Pulmão/citologia , Pulmão/embriologia , Receptores de Glucocorticoides/metabolismo , Animais , Aquaporinas/genética , Aquaporinas/metabolismo , Diferenciação Celular/fisiologia , Embrião de Mamíferos/fisiologia , Células Epiteliais/ultraestrutura , Canais Epiteliais de Sódio , Feminino , Glucocorticoides/metabolismo , Pulmão/metabolismo , Glicoproteínas de Membrana , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Fenótipo , Gravidez , Proteínas Associadas a Surfactantes Pulmonares/genética , Proteínas Associadas a Surfactantes Pulmonares/metabolismo , Surfactantes Pulmonares , Receptores de Glucocorticoides/genética , Canais de Sódio/genética , Canais de Sódio/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...