Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Infect Dis ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38718217

RESUMO

BACKGROUND: The substantial risk for respiratory and invasive infections with Streptococcus pneumoniae (Spn) among people with HIV-1 (PWH) begins with asymptomatic colonization. The frequency of Spn colonization among U.S. adults with and without HIV-1 infection is not well-characterized in the conjugate vaccine era. METHODS: We determined Spn colonization frequency by culture and specific lytA gene QPCR and microbiota profile by 16S rRNA gene sequencing in nasopharyngeal (NP) and oropharyngeal (OP) DNA from 138 PWH and 93 control adults and associated clinical characteristics. RESULTS: The frequencies of Spn colonization among PWH and controls did not differ (11.6% vs 8.6%, respectively; p=0.46) using combined results of culture and PCR, independent of vaccination or behavioral risks. PWH showed altered microbiota composition (i.e., beta-diversity. NP: p=0.0028, OP: p=0.0098), decreased alpha-diversity (NP: p=0.024, OP: p=0.0045), and differences in the relative abundance of multiple bacterial taxa. Spn colonization was associated with altered beta-diversity in the NP (p=0.011), but not OP (p=0.21). CONCLUSIONS: Despite widespread conjugate vaccine and antiretroviral use, frequencies of Spn colonization among PWH and controls are currently consistent with those reported in the pre-conjugate era. The persistently increased risk of pneumococcal disease despite ART may relate to behavioral and immunologic variables other than colonization.

2.
AIDS Behav ; 27(11): 3678-3686, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37247044

RESUMO

Pre-exposure prophylaxis (PrEP) reduces human immunodeficiency virus (HIV) transmission through sexual contact by at least 90% when taken as prescribed. This retrospective cohort study evaluated differences in adherence to PrEP medication and monitoring between the physician- and nurse practitioner (NP)-led in-person setting and the pharmacist-led telehealth setting among patients followed by the infectious diseases clinic at the VA Eastern Colorado Health Care System from July 2012 to February 2021. The primary outcomes were PrEP tablets filled per person-year, serum creatinine (SCr) tests per person-year, and HIV screens per person-year. Secondary outcomes included sexually transmitted infection (STI) screens per person-year and patients lost to follow-up.149 patients were included in the study, with 167 person-years in the in-person cohort and 153 person-years in the telehealth cohort. Adherence to PrEP medications and monitoring was similar between in-person and telehealth clinics. PrEP tablets filled per person-year was 324 in the in-person cohort and 321 in the telehealth cohort (RR = 0.99; 95% CI, 0.98-1.00). SCr screens per person-year was 3.51 in the in-person cohort and 3.37 in the telehealth cohort (RR = 0.96; 95% CI, 0.85-1.07). HIV screens per person-year was 3.55 in the in-person cohort and 3.38 in the telehealth cohort (RR = 0.95; 95% CI, 0.85-1.07). There were no new HIV infections. Additionally, patients were less likely to be lost to follow-up when followed via telehealth (11.9% vs. 30.0%), Χ2 (1, N = 149) = 6.85, p = 0.009. These findings indicate that pharmacist-driven delivery of PrEP via telehealth can be used to increase access to PrEP without sacrificing quality of care.

3.
J Immunol ; 206(10): 2402-2411, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33931485

RESUMO

Pneumococcal infections are common and serious complications of HIV-1 disease. Prevention has been compromised by the limited magnitude and quality of Ab responses to T cell-independent type 2 pneumococcal capsular polysaccharides (PPS). The pneumococcal polysaccharide-protein conjugate vaccine-13 (PCV-13) contains PPS conjugated to the T cell-dependent protein (diphtheria toxoid [DT] [CRM197]). We investigated the differential response to PPS and DT by human Ab-secreting B cells (ASC) after immunization with PCV-13 in newly diagnosed healthy HIV+ and control adults. The numbers of PPS-specific IgG ASC increased significantly and similarly in HIV+ and controls. However, DT-specific IgG ASC increased in controls but not HIV+ subjects. To determine the cellular basis of these disparate responses to DT and PPS, we characterized the frequency and activation of T follicular helper (Tfh) cells, the predominant T cell subset providing B cell help. Expression of inducible T cell costimulator (ICOS), which sustains Tfh function and phenotype, increased significantly among controls, when compared with the HIV+ group. Increases in ICOS+ Tfh correlated with changes in T-dependent, DT-specific IgG ASC in controls but not in HIV+ In contrast, ICOS expression did not correlate with T cell-independent type 2 PPS-specific ASC in either group. Of note, upon optimized ex vivo stimulation, CD4 T cells from HIV+ subjects differentiated into Tfh cells and formed synapses with Raji B cells at frequencies similar to that of controls. In summary, PCV-13-induced increase in ICOS expression on Tfh was associated with responses to DT, which was compromised in recently diagnosed healthy HIV+ adults and can be restored ex vivo by providing effective Tfh-differentiating signals.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Imunidade Adaptativa , HIV-1/imunologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Células T Auxiliares Foliculares/imunologia , Vacinação/métodos , Vacinas Conjugadas/imunologia , Infecções Oportunistas Relacionadas com a AIDS/sangue , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Linfócitos B/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Imunogenicidade da Vacina , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Infecções Pneumocócicas/sangue , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/microbiologia , Resultado do Tratamento , Adulto Jovem
4.
Rheumatology (Oxford) ; 60(1): 60-72, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33099651

RESUMO

OBJECTIVES: We conducted a systematic review and meta-analysis to determine the magnitude of infection risk in patients with SLE and evaluate the effect of general and SLE-related factors on infection risk. METHODS: We searched MEDLINE and Embase from inception to July 2018, screening for observational studies that evaluated infection risk in patients with SLE compared with the general population/healthy controls. Outcomes of interest included overall severe infection, herpes zoster infection/reactivation, opportunistic infections, pneumonia and tuberculosis. Random-effects models were used to calculate pooled risk ratios (RRs) for each type of infection. Sensitivity analysis assessed the impact of removing studies with high risk of bias. RESULTS: Eleven retrospective or prospective cohort studies were included in the meta-analysis: overall severe infection (n = 4), pneumonia (n = 6), tuberculosis (n = 3) and herpes zoster (n = 2). Pooled RRs for overall severe infection significantly increased for patients with SLE compared with the general population/healthy controls [RR 2.96 (95% CI 1.28, 6.83)]. Pooled RRs for pneumonia, herpes zoster and tuberculosis showed significantly increased risk compared with the general population/healthy controls [RR 2.58 (1.80, 3.70), 2.50 (2.36, 2.65) and 6.11 (3.61, 10.33), respectively]. Heterogeneity and evidence of publication bias were present for all analyses, except herpes zoster. Sensitivity analyses confirmed robustness of the results. CONCLUSION: Patients with SLE have significantly higher risk of infection compared with the general population/healthy controls. Efforts to strengthen strategies aimed at preventing infections in SLE are needed. PROTOCOL REGISTRATION: PROSPERO number: CRD42018109425.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Infecções Oportunistas/etiologia , Herpes Zoster/etiologia , Hospitalização/estatística & dados numéricos , Humanos , Tuberculose/etiologia
5.
Cytokine ; 146: 155650, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34343865

RESUMO

IL-6 family cytokines display broad effects in haematopoietic and non-haematopoietic cells that regulate immune homeostasis, host defence, haematopoiesis, development, reproduction and wound healing. Dysregulation of these activities places this cytokine family as important mediators of autoimmunity, chronic inflammation and cancer. In this regard, ectopic lymphoid structures (ELS) are a pathological hallmark of many tissues affected by chronic disease. These inducible lymphoid aggregates form compartmentalised T cell and B cell zones, germinal centres, follicular dendritic cell networks and high endothelial venules, which are defining qualities of peripheral lymphoid organs. Accordingly, ELS can support local antigen-specific responses to self-antigens, alloantigens, pathogens and tumours. ELS often correlate with severe disease progression in autoimmune conditions, while tumour-associated ELS are associated with enhanced anti-tumour immunity and a favourable prognosis in cancer. Here, we discuss emerging roles for IL-6 family cytokines as regulators of ELS development, maintenance and activity and consider how modulation of these activities has the potential to aid the successful treatment of autoimmune conditions and cancers where ELS feature.


Assuntos
Interleucina-6/metabolismo , Tecido Linfoide/metabolismo , Autoimunidade , Humanos , Inflamação/patologia , Receptores de Interleucina-6/metabolismo , Células Estromais/metabolismo
6.
J Cell Mol Med ; 24(22): 13546-13550, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079455

RESUMO

The leading cause of central vision loss, age-related macular degeneration (AMD), is a degenerative disorder characterized by atrophy of retinal pigment epithelium (RPE) and photoreceptors. For 15% of cases, neovascularization occurs, leading to acute vision loss if left untreated. For the remaining patients, there are currently no treatment options and preventing progressive RPE atrophy remains the main therapeutic goal. Previously, we have shown treatment with interleukin-33 can reduce choroidal neovascularization and attenuate tissue remodelling. Here, we investigate IL-33 delivery in aged, high-fat diet (HFD) fed mice on a wildtype and complement factor H heterozygous knockout background. We characterize the non-toxic effect following intravitreal injection of IL-33 and further demonstrate protective effects against RPE cell death with evidence of maintaining metabolic retinal homeostasis of Cfh+/-~HFD mice. Our results further support the potential utility of IL-33 to prevent AMD progression.


Assuntos
Envelhecimento , Interleucina-33/farmacologia , Degeneração Retiniana/etiologia , Degeneração Retiniana/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Degeneração Macular/etiologia , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Camundongos , Camundongos Knockout , Degeneração Retiniana/tratamento farmacológico , Degeneração Retiniana/patologia , Epitélio Pigmentado da Retina/patologia , Epitélio Pigmentado da Retina/ultraestrutura , Resultado do Tratamento
7.
Exp Eye Res ; 191: 107901, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31877281

RESUMO

Persistent non-infectious uveitis has a significant morbidity, but the extent to which this is accompanied by inflammation driven remodelling of the tissue is unclear. To address this question, we studied a series of samples selected from two ocular tissue repositories and identified 15 samples with focal infiltration. Eleven of fifteen contained lymphocytes, both B cells (CD20 positive) and T cells (CD3 positive). In 20% of the samples there was evidence of ectopic lymphoid like structures with focal aggregations of B cells and T cells, segregated into anatomically different adjacent zones. To investigate inflammation in the tissue, an analysis of 520 immune relevant transcripts was carried out and 24 genes were differentially upregulated, compared with control tissue. Two of these (CD14 and fibronectin) were increased in ocular inflammation compared to control immune tissue (tonsil). We demonstrate that in a significant minority of patients, chronic persistent uveitis leads to dysregulation of ocular immune surveillance, characterized by the development of areas of local ectopic lymphoid like structures, which may be a target for therapeutic intervention directed at antibody producing cells.


Assuntos
Pan-Uveíte/patologia , Estruturas Linfoides Terciárias/patologia , Adolescente , Adulto , Idoso , Antígenos CD20/metabolismo , Linfócitos B/imunologia , Complexo CD3/metabolismo , Feminino , Fibronectinas/metabolismo , Humanos , Imuno-Histoquímica , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Pan-Uveíte/imunologia , Linfócitos T/imunologia , Estruturas Linfoides Terciárias/imunologia
8.
J Immunol ; 198(1): 138-146, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27895173

RESUMO

Regulatory T cells (Treg) attenuate dendritic cell (DC) maturation and stimulatory function. Current knowledge on the functional impact of semimature DC is limited to CD4+ T cell proliferation and cytokine production. Little is known about the molecular basis underpinning the functional effects of Treg-treated DC (Treg-DC). We present novel evidence that Treg-DC skewed CD4+ naive T cell polarization toward a regulatory phenotype and impaired CD8+ T cell allo-reactive responses, including their ability to induce target tissue damage in a unique in vitro human graft-versus-host disease skin explant model. Microarray analysis clustered Treg-DC as a discrete population from mature-DC and immature-DC, with 51 and 93 genes that were significantly over- or underexpressed, respectively, compared with mature-DC. Quantitative real-time PCR analysis revealed an intermediate expression level of CD38, CD83, CD80 and CD86 mRNA in Treg-DC, lower than mature-DC, higher than immature-DC. We also observed an attenuation of NF-κB pathway, an upstream regulator of the aforementioned genes, concomitant with reduced expression of two NF-κB-signaling related genes RELB and NFκBIZ, in the Treg-DC, together with an increased expression of Wnt5a, a negative regulator of DC differentiation. We further confirmed that the Treg-DC-mediated skewed CD4+ naive T cell polarization resulted from decreased IL-12 secretion by Treg-DC, which may be post-transcriptionally modulated by decreased expression of microRNA-155 in Treg-DC. To our knowledge, this is the first study demonstrating a transcriptional modulation of DC function by human Treg, partially via attenuation of the NF-κB signaling pathway and upregulation of Wnt5a, suggesting Treg may interfere with DC reprogramming during maturation, thereby modulating DC function.


Assuntos
Diferenciação Celular/imunologia , Células Dendríticas/imunologia , Linfócitos T Reguladores/imunologia , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/citologia , Citometria de Fluxo , Regulação da Expressão Gênica/imunologia , Humanos , Ativação Linfocitária/imunologia , NF-kappa B/imunologia , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/imunologia , Transcrição Gênica , Proteína Wnt-5a/imunologia , Proteína Wnt-5a/metabolismo
9.
Haematologica ; 102(4): 736-745, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27979926

RESUMO

Relapsed acute lymphoblastic leukemia is the most common cause of cancer-related mortality in young people and new therapeutic strategies are needed to improve outcome. Recent studies have shown that heterozygous inactivating mutations in the histone acetyl transferase, CREBBP, are particularly frequent in relapsed childhood acute lymphoblastic leukemia and associated with a hyperdiploid karyotype and KRAS mutations. To study the functional impact of CREBBP haploinsufficiency in acute lymphoblastic leukemia, RNA interference was used to knock down expression of CREBBP in acute lymphoblastic leukemia cell lines and various primagraft acute lymphoblastic leukemia cells. We demonstrate that attenuation of CREBBP results in reduced acetylation of histone 3 lysine 18, but has no significant impact on cAMP-dependent target gene expression. Impaired induction of glucocorticoid receptor targets was only seen in 1 of 4 CREBBP knockdown models, and there was no significant difference in glucocorticoid-induced apoptosis, sensitivity to other acute lymphoblastic leukemia chemotherapeutics or histone deacetylase inhibitors. Importantly, we show that CREBBP directly acetylates KRAS and that CREBBP knockdown enhances signaling of the RAS/RAF/MEK/ERK pathway in Ras pathway mutated acute lymphoblastic leukemia cells, which are still sensitive to MEK inhibitors. Thus, CREBBP mutations might assist in enhancing oncogenic RAS signaling in acute lymphoblastic leukemia but do not alter response to MEK inhibitors.


Assuntos
Proteína de Ligação a CREB/deficiência , Sistema de Sinalização das MAP Quinases , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas ras/genética , Acetilação , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Histonas/metabolismo , Humanos , Camundongos , Camundongos Knockout , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Receptores de Glucocorticoides/metabolismo , Especificidade por Substrato , Resultado do Tratamento
10.
Am J Pathol ; 185(8): 2324-35, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26079814

RESUMO

One of the main drivers for neovascularization in age-related macular degeneration is activation of innate immunity in the presence of macrophages. Here, we demonstrate that T helper cell type 2 cytokines and, in particular, IL-4 condition human and murine monocyte phenotype toward Arg-1(+), and their subsequent behavior limits angiogenesis by increasing soluble fms-like tyrosine kinase 1 (sFlt-1) gene expression. We document that T helper cell type 2 cytokine-conditioned murine macrophages neutralize vascular endothelial growth factor-mediated endothelial cell proliferation (human umbilical vein endothelial cell and choroidal vasculature) in a sFlt-1-dependent manner. We demonstrate that in vivo intravitreal administration of IL-4 attenuates laser-induced choroidal neovascularization (L-CNV) due to specific IL-4 conditioning of macrophages. IL-4 induces the expression of sFlt-1 by resident CD11b(+) retinal microglia and infiltrating myeloid cells but not from retinal pigment epithelium. IL-4-induced suppression of L-CNV is not prevented when sFlt-1 expression is attenuated in retinal pigment epithelium. IL-4-mediated suppression of L-CNV was abrogated in IL-4R-deficient mice and in bone marrow chimeras reconstituted with myeloid cells that had undergone lentiviral-mediated shRNA silencing of sFlt-1, demonstrating the critical role of this cell population. Together, these data establish how lL-4 directly drives macrophage sFlt-1 production expressing an Arg-1(+) phenotype and support the therapeutic potential of targeted IL-4 conditioning within the tissue to regulate disease conditions such as neovascular age-related macular degeneration.


Assuntos
Arginase/metabolismo , Neovascularização de Coroide/metabolismo , Interleucina-4/farmacologia , Macrófagos/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Interleucina-13/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Retina/efeitos dos fármacos , Retina/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
J Immunol ; 192(10): 4541-50, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24740509

RESUMO

Experimental autoimmune uveoretinitis is a model for noninfectious posterior segment intraocular inflammation in humans. Although this disease is CD4(+) T cell dependent, in the persistent phase of disease CD8(+) T cells accumulate. We show that these are effector memory CD8(+) T cells that differ from their splenic counterparts with respect to surface expression of CD69, CD103, and Ly6C. These retinal effector memory CD8(+) T cells have limited cytotoxic effector function, are impaired in their ability to proliferate in response to Ag-specific stimulation, and upregulate programmed death 1 receptor. Treatment with fingolimod (FTY720) during the late phase of disease revealed that retinal CD8(+) T cells were tissue resident. Despite signs of exhaustion, these cells were functional, as their depletion resulted in an expansion of retinal CD4(+) T cells and CD11b(+) macrophages. These results demonstrate that, during chronic autoimmune inflammation, exhausted CD8(+) T cells become established in the local tissue. They are phenotypically distinct from peripheral CD8(+) T cells and provide local signals within the tissue by expression of inhibitory receptors such as programmed death 1 that limit persistent inflammation.


Assuntos
Doenças Autoimunes/imunologia , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica , Retinite/imunologia , Doenças da Úvea/imunologia , Animais , Doenças Autoimunes/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Galinhas , Doença Crônica , Modelos Animais de Doenças , Humanos , Camundongos , Especificidade de Órgãos , Receptor de Morte Celular Programada 1/imunologia , Retinite/patologia , Doenças da Úvea/patologia
12.
Immunology ; 146(2): 301-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26152845

RESUMO

Experimental autoimmune uveoretinitis (EAU) in the C57BL/6J mouse is a model of non-infectious posterior segment intraocular inflammation that parallels clinical features of the human disease. The purpose of this study was to analyse the immune response to the four murine subunits of retinol binding protein-3 (RBP-3) to identify pathogenic epitopes to investigate the presence of intramolecular epitope spreading during the persistent inflammation phase observed in this model of EAU. Recombinant murine subunits of the RBP-3 protein were purified and used to immunize C57BL/6J mice to induce EAU. An overlapping peptide library was used to screen RBP-3 subunit 3 for immunogenicity and pathogenicity. Disease phenotype and characterization of pathogenic subunits and peptides was undertaken by topical endoscopic fundal imaging, immunohistochemistry, proliferation assays and flow cytometry. RBP-3 subunits 1, 2 and 3 induced EAU in the C57BL/6J mice, with subunit 3 eliciting the most destructive clinical disease. Within subunit 3 we identified a novel uveitogenic epitope, 629-643. The disease induced by this peptide was comparable to that produced by the uveitogenic 1-20 peptide. Following immunization, peptide-specific responses by CD4(+) and CD8(+) T-cell subsets were detected, and cells from both populations were present in the retinal inflammatory infiltrate. Intramolecular epitope spreading between 629-643 and 1-20 was detected in mice with clinical signs of disease. The 629-643 RBP-3 peptide is a major uveitogenic peptide for the induction of EAU in C57BL/6J mice and the persistent clinical disease induced with one peptide leads to epitope spreading.


Assuntos
Doenças Autoimunes/imunologia , Epitopos/imunologia , Proteínas do Olho/imunologia , Fragmentos de Peptídeos/imunologia , Retina/imunologia , Retinite/imunologia , Proteínas de Ligação ao Retinol/imunologia , Úvea/imunologia , Uveíte/imunologia , Animais , Doenças Autoimunes/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Mapeamento de Epitopos , Epitopos/genética , Proteínas do Olho/genética , Feminino , Humanos , Ativação Linfocitária , Camundongos Endogâmicos C57BL , Fragmentos de Peptídeos/genética , Fenótipo , Retina/patologia , Retinite/patologia , Proteínas de Ligação ao Retinol/genética , Índice de Gravidade de Doença , Úvea/patologia , Uveíte/patologia
13.
Br J Haematol ; 171(4): 595-605, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26310606

RESUMO

Glucocorticoid (GC) resistance is a continuing clinical problem in childhood acute lymphoblastic leukaemia (ALL) but the underlying mechanisms remain unclear. A proteomic approach was used to compare profiles of the B-lineage ALL GC-sensitive cell line, PreB 697, and its GC-resistant sub-line, R3F9, pre- and post-dexamethasone exposure. PAX5, a transcription factor critical to B-cell development was differentially regulated in the PreB 697 compared to the R3F9 cell line in response to GC. PAX5 basal protein expression was less in R3F9 compared to its GC-sensitive parent and confirmed to be lower in other GC-resistant sub-lines of Pre B 697 and was associated with a decreased expression of the PAX5 transcriptional target, CD19. Gene set enrichment analysis showed that increasing GC-resistance was associated with differentiation from preB-II to an immature B-lymphocyte stage. GC-resistant sub-lines were shown to have higher levels of phosphorylated JNK compared to the parent line and JNK inhibition caused re-sensitization to GC. Exploiting this maturation may be key to overcoming GC resistance and targeting signalling pathways linked to the maturation state, such as JNK, may be a novel approach.


Assuntos
Antineoplásicos/farmacologia , Linfócitos B/efeitos dos fármacos , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , MAP Quinase Quinase 4/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas de Neoplasias/biossíntese , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteômica/métodos , Apoptose/efeitos dos fármacos , Linfócitos B/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/fisiologia , Éxons/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Reação em Cadeia da Polimerase Multiplex , Mutação , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Fator de Transcrição PAX5/genética , Fator de Transcrição PAX5/fisiologia , Fosforilação/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/enzimologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas em Tandem
14.
Sci Transl Med ; 16(750): eadi4125, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838135

RESUMO

Chronic inflammation is a constitutive component of many age-related diseases, including age-related macular degeneration (AMD). Here, we identified interleukin-1 receptor-associated kinase M (IRAK-M) as a key immunoregulator in retinal pigment epithelium (RPE) that declines during the aging process. Rare genetic variants of IRAK3, which encodes IRAK-M, were associated with an increased likelihood of developing AMD. In human samples and mouse models, IRAK-M abundance in the RPE declined with advancing age or exposure to oxidative stress and was further reduced in AMD. Irak3-knockout mice exhibited an increased incidence of outer retinal degeneration at earlier ages, which was further exacerbated by oxidative stressors. The absence of IRAK-M led to a disruption in RPE cell homeostasis, characterized by compromised mitochondrial function, cellular senescence, and aberrant cytokine production. IRAK-M overexpression protected RPE cells against oxidative or immune stressors. Subretinal delivery of adeno-associated virus (AAV)-expressing human IRAK3 rescued light-induced outer retinal degeneration in wild-type mice and attenuated age-related spontaneous retinal degeneration in Irak3-knockout mice. Our data show that replenishment of IRAK-M in the RPE may redress dysregulated pro-inflammatory processes in AMD, suggesting a potential treatment for retinal degeneration.


Assuntos
Quinases Associadas a Receptores de Interleucina-1 , Camundongos Knockout , Estresse Oxidativo , Degeneração Retiniana , Epitélio Pigmentado da Retina , Animais , Humanos , Masculino , Camundongos , Senescência Celular , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Quinases Associadas a Receptores de Interleucina-1/genética , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Degeneração Macular/genética , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Degeneração Retiniana/genética , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia
15.
Am J Pathol ; 180(2): 672-81, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22119714

RESUMO

Fingolimod (FTY720) is an FDA-approved therapeutic drug with efficacy demonstrated in experimental models of multiple sclerosis and in phase III human multiple sclerosis trials. Fingolimod prevents T-cell migration to inflammatory sites by decreasing expression of the sphingosine-1 phosphate receptor normally required for egress from secondary lymphoid tissue. As a preclinical model of human uveitis, experimental autoimmune uveoretinitis permits assessment of immunotherapeutic efficacy. Murine experimental autoimmune uveoretinitis is induced by activation of retinal antigen-specific CD4(+) T cells that infiltrate the eye. High-dose fingolimod treatment administered before disease onset reduces ocular infiltration within hours of administration and suppresses clinicopathologic expression of experimental autoimmune uveoretinitis. In the present investigation of the efficacy of fingolimod treatment for established disease, single-dose treatment was effective and immunosuppressive ability was maintained through a dose range, demonstrating significant and rapid reduction in CD4(+) cell infiltration at clinically relevant therapeutic doses of fingolimod. A repeated-treatment regimen using a dose similar to that in current multiple sclerosis patient protocols significantly reduced infiltration within 24 hours of administration; importantly, repeated doses did not compromise the vascular integrity of the blood-ocular barrier. On withdrawal of fingolimod, drug-induced remission was lost and recrudescence of clinical disease was observed. These results support a strong therapeutic potential for fingolimod as an acute rescue therapy for the treatment of ocular immune-mediated inflammation.


Assuntos
Doenças Autoimunes/prevenção & controle , Barreira Hematorretiniana/efeitos dos fármacos , Imunossupressores/farmacologia , Propilenoglicóis/farmacologia , Retinite/prevenção & controle , Esfingosina/análogos & derivados , Uveíte/prevenção & controle , Animais , Apoptose , Doenças Autoimunes/patologia , Barreira Hematorretiniana/patologia , Relação Dose-Resposta a Droga , Feminino , Cloridrato de Fingolimode , Imunossupressores/administração & dosagem , Camundongos , Microvasos/patologia , Permeabilidade , Propilenoglicóis/administração & dosagem , Retinite/patologia , Esfingosina/administração & dosagem , Esfingosina/farmacologia , Uveíte/patologia
16.
Genes Chromosomes Cancer ; 51(3): 250-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22072526

RESUMO

Casitas B-lineage lymphoma (CBL) proteins are RING finger ubiquitin E3 ligases that attenuate the signaling of receptor tyrosine kinases and are mutated in a number of myeloid disorders. In this study, mutational screening of the linker-RING domains of CBL and CBLB was performed by denaturing high performance liquid chromatography in a cohort of diagnostic (n = 180) or relapse (n = 46) samples from children with acute lymphoblastic leukemia. Somatic mutations were identified in three children, giving an overall incidence of 1.7% and involved small deletions affecting the intron/exon boundaries of exon 8, leading to skipping of exon 8 and abolishing E3 ligase function. Mutated primary samples were associated with constitutive activation of the RAS pathway and sensitivity to MEK inhibitors was shown. Thus, mutation of CBL is an alternative route to activate the RAS pathway and may identify children who are candidates for MEK inhibitor clinical trials.


Assuntos
Mutação , Proteína Oncogênica v-cbl/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Transdução de Sinais/genética , Adolescente , Sequência de Bases , Criança , Pré-Escolar , Cromatografia Líquida , Estudos de Coortes , Análise Mutacional de DNA , Éxons , Feminino , Humanos , Íntrons , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Masculino , Dados de Sequência Molecular , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Domínios RING Finger , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Recidiva , Reino Unido
17.
Biomed Opt Express ; 14(7): 3413-3432, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37497491

RESUMO

This paper presents methods for the detection and assessment of non-infectious uveitis, a leading cause of vision loss in working age adults. In the first part, we propose a classification model that can accurately predict the presence of uveitis and differentiate between different stages of the disease using optical coherence tomography (OCT) images. We utilize the Grad-CAM visualization technique to elucidate the decision-making process of the classifier and gain deeper insights into the results obtained. In the second part, we apply and compare three methods for the detection of detached particles in the retina that are indicative of uveitis. The first is a fully supervised detection method, the second is a marked point process (MPP) technique, and the third is a weakly supervised segmentation that produces per-pixel masks as output. The segmentation model is used as a backbone for a fully automated pipeline that can segment small particles of uveitis in two-dimensional (2-D) slices of the retina, reconstruct the volume, and produce centroids as points distribution in space. The number of particles in retinas is used to grade the disease, and point process analysis on centroids in three-dimensional (3-D) shows clustering patterns in the distribution of the particles on the retina.

18.
ERJ Open Res ; 9(3)2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37143844

RESUMO

Objective: Inhalation therapy is the cornerstone of COPD, together with non-pharmacological treatments. Long-acting muscarinic antagonists (LAMAs), alone or in combination with long-acting ß-agonists (LABAs), are commonly used. Pressurised metered-dose inhalers (pMDIs), dry powder inhalers (DPIs) and soft-mist inhalers (SMIs) are used, each with different carbon footprints. This study aimed to assess the carbon footprint of hypothetically replacing LAMA or LAMA/LABA inhalers with an SMI, Respimat Reusable, within the same therapeutic class. Methods: An environmental impact model was established to assess the change in carbon footprint of replacing pMDIs/DPIs with Respimat Reusable within the same therapeutic class (LAMA or LAMA/LABA) across 12 European countries and the USA over 5 years. Inhaler use for country and disease-specific populations was derived from international prescribing data and the associated carbon footprint (CO2 equivalents (CO2e)) was identified from published sources. Results: Over 5 years and across all countries, replacing LAMA inhalers with Spiriva Respimat Reusable reduced CO2e emissions by 13.3-50.9%, saving 93-6228 tonnes of CO2e in the different countries studied. Replacing LAMA/LABA inhalers with Spiolto Respimat Reusable reduced CO2e emissions by 9.5-92.6%, saving 31-50 843 tonnes of CO2e. In scenario analyses, which included total replacement of DPIs/pMDIs, consistent CO2e savings were estimated. Sensitivity analyses showed that results were sensitive to changes in several parameters including varying assumptions around reusability of inhalers and potential CO2e impact. Conclusion: Replacement of pMDIs and DPIs with Respimat Reusable within the same therapeutic class would result in substantial reductions in CO2e emissions.

19.
Front Ophthalmol (Lausanne) ; 3: 1184937, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38983082

RESUMO

Ophthalmic autoimmune and autoinflammatory conditions cause significant visual morbidity and require complex medical treatment complicated by significant side effects and lack of specificity. Regulatory T cells (Tregs) have key roles in immune homeostasis and in the resolution of immune responses. Polyclonal Treg therapy has shown efficacy in treating autoimmune disease. Genetic engineering approaches to produce antigen-specific Treg therapy has the potential for enhanced treatment responses and fewer systemic side effects. Cell therapy using chimeric antigen receptor modified T cell (CAR-T) therapy, has had significant success in treating haematological malignancies. By modifying Tregs specifically, a CAR-Treg approach has been efficacious in preclinical models of autoimmune conditions leading to current phase 1-2 clinical trials. This review summarises CAR structure and design, Treg cellular biology, developments in CAR-Treg therapies, and discusses future strategies to apply CAR-Treg therapy in the treatment of ophthalmic conditions.

20.
bioRxiv ; 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37808640

RESUMO

Unchecked, chronic inflammation is a constitutive component of age-related diseases, including age-related macular degeneration (AMD). Here we identified interleukin-1 receptor-associated kinase (IRAK)-M as a key immunoregulator in retinal pigment epithelium (RPE) that declines with age. Rare genetic variants of IRAK-M increased the likelihood of AMD. IRAK-M expression in RPE declined with age or oxidative stress and was further reduced in AMD. IRAK-M-deficient mice exhibited increased incidence of outer retinal degeneration at earlier ages, which was further exacerbated by oxidative stressors. The absence of IRAK-M disrupted RPE cell homeostasis, including compromised mitochondrial function, cellular senescence, and aberrant cytokine production. IRAK-M overexpression protected RPE cells against oxidative or immune stressors. Subretinal delivery of AAV-expressing IRAK-M rescued light-induced outer retinal degeneration in wild-type mice and attenuated age-related spontaneous retinal degeneration in IRAK-M-deficient mice. Our data support that replenishment of IRAK-M expression may redress dysregulated pro-inflammatory processes in AMD, thereby treating degeneration.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA