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1.
Nat Commun ; 12(1): 4571, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34315874

RESUMO

Understanding mechanisms of hepatocellular damage may lead to new treatments for liver disease, and genome-wide association studies (GWAS) of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) serum activities have proven useful for investigating liver biology. Here we report 100 loci associating with both enzymes, using GWAS across 411,048 subjects in the UK Biobank. The rare missense variant SLC30A10 Thr95Ile (rs188273166) associates with the largest elevation of both enzymes, and this association replicates in the DiscovEHR study. SLC30A10 excretes manganese from the liver to the bile duct, and rare homozygous loss of function causes the syndrome hypermanganesemia with dystonia-1 (HMNDYT1) which involves cirrhosis. Consistent with hematological symptoms of hypermanganesemia, SLC30A10 Thr95Ile carriers have increased hematocrit and risk of iron deficiency anemia. Carriers also have increased risk of extrahepatic bile duct cancer. These results suggest that genetic variation in SLC30A10 adversely affects more individuals than patients with diagnosed HMNDYT1.


Assuntos
Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Proteínas de Transporte de Cátions/genética , Estudo de Associação Genômica Ampla , Manganês/sangue , Mutação/genética , Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica , Ligação Genética , Loci Gênicos , Genoma Humano , Células HeLa , Hematócrito , Heterozigoto , Homeostase , Humanos , Fígado/patologia , Manganês/metabolismo , Anotação de Sequência Molecular , Fenótipo , Reprodutibilidade dos Testes
2.
J Pharmacol Exp Ther ; 376(3): 428-435, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33443084

RESUMO

Nephrotic syndrome (NS) is associated with metabolic perturbances including profound dyslipidemia characterized by hypercholesterolemia and hypertriglyceridemia. A major underlying mechanism of hypertriglyceridemia in NS is lipoprotein lipase (LPL) deficiency and dysfunction. There is emerging evidence that elevated angiopoietin-like protein 3 (ANGPTL3), an LPL inhibitor that is primarily expressed and secreted by hepatocytes, may be in part responsible for these findings. Furthermore, there is evidence pointing to the contribution of ANGPTL3 to the pathogenesis of proteinuria in NS. Therefore, we hypothesized that inhibition of hepatic ANGPTL3 by RNA interference will ameliorate dyslipidemia and other symptoms of NS and pave the way for a new therapeutic strategy. To this end, we used a subcutaneously delivered, GalNAc (N-Acetylgalactosamine)-conjugated small interfering RNA (siRNA) to selectively target and suppress liver Angptl3 in rats with puromycin-induced NS, which exhibits clinical features of NS including proteinuria, hypoalbuminemia, hyperlipidemia, and renal histologic abnormalities. The study demonstrated that siRNA-mediated knockdown of the liver Angptl3 relieved its inhibitory effect on LPL and significantly reduced hypertriglyceridemia in nephrotic rats. This was accompanied by diminished proteinuria and hypoalbuminemia, which are the hallmarks of NS, and significant attenuation of renal tissue inflammation and oxidative stress. Taken together, this study confirmed the hypothesis that suppression of Angptl3 is protective in NS and points to the possibility that the use of RNA interference to suppress hepatic Angptl3 can serve as a novel therapeutic strategy for NS. SIGNIFICANCE STATEMENT: The current standard of care for mitigating nephrotic dyslipidemia in nephrotic syndrome is statins therapy. However, the efficacy of statins and its safety in the context of impaired kidney function is not well established. Here, we present an alternate therapeutic approach by using siRNA targeting Angptl3 expressed in hepatocytes. As the liver is the major source of circulating Angptl3, siRNA treatment reduced the profound hypertriglyceridemia in a rat model of nephrotic syndrome and was also effective in improving kidney and cardiac function.


Assuntos
Hipertrigliceridemia/complicações , Fígado/metabolismo , Síndrome Nefrótica/genética , Síndrome Nefrótica/prevenção & controle , Interferência de RNA , Animais , Modelos Animais de Doenças , Lipase Lipoproteica/metabolismo , Masculino , Síndrome Nefrótica/complicações , Ratos , Ratos Sprague-Dawley
3.
PLoS One ; 15(7): e0236892, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735622

RESUMO

There is a significant unmet need for a safe and effective therapy for the treatment of children with congenital hyperinsulinism. We hypothesized that amplification of the glucagon signaling pathway could ameliorate hyperinsulinism associated hypoglycemia. In order to test this we evaluated the effects of loss of Prkar1a, a negative regulator of Protein Kinase A in the context of hyperinsulinemic conditions. With reduction of Prkar1a expression, we observed a significant upregulation of hepatic gluconeogenic genes. In wild type mice receiving a continuous infusion of insulin by mini-osmotic pump, we observed a 2-fold increase in the level of circulating ketones and a more than 40-fold increase in Kiss1 expression with reduction of Prkar1a. Loss of Prkar1a in the Sur1-/- mouse model of KATP hyperinsulinism significantly attenuated fasting induced hypoglycemia, decreased the insulin/glucose ratio, and also increased the hepatic expression of Kiss1 by more than 10-fold. Together these data demonstrate that amplification of the hepatic glucagon signaling pathway is able to rescue hypoglycemia caused by hyperinsulinism.


Assuntos
Hiperinsulinismo Congênito/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Kisspeptinas/genética , Receptores de Sulfonilureias/genética , Animais , Hiperinsulinismo Congênito/genética , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Gluconeogênese/genética , Glucose/metabolismo , Hipoglicemia/metabolismo , Insulina/metabolismo , Cetonas/metabolismo , Kisspeptinas/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Knockout , Transdução de Sinais
4.
Mol Genet Metab ; 118(3): 198-205, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27211612

RESUMO

OBJECTIVE: This was an open-label, phase 1/2 dose-escalation, safety trial of intrathecal recombinant human heparan-N-sulfatase (rhHNS) administered via intrathecal drug delivery device (IDDD) for treating mucopolysaccharidosis IIIA (NCT01155778). STUDY DESIGN: Twelve patients received 10, 45, or 90mg of rhHNS via IDDD once monthly for a total of 6 doses. Primary endpoints included adverse events (AEs) and anti-rhHNS antibodies. Secondary endpoints included standardized neurocognitive assessments, cortical gray matter volume, and pharmacokinetic/pharmacodynamic analyses. RESULTS: All patients experienced treatment-emergent AEs; most of mild-to-moderate severity. Seven patients reported a total of 10 serious AEs (SAEs), all but one due to hospitalization to revise a nonfunctioning IDDD. No SAEs were considered related to rhHNS. Anti-rhHNS antibodies were detected in the serum of 6 patients and in the cerebrospinal fluid (CSF) of 2 of these. CSF heparan sulfate levels were elevated at baseline and there were sustained declines in all tested patients following the first rhHNS dose. No impact of anti-rhHNS antibodies on any pharmacodynamic or safety parameters was evident. 4 of 12 patients showed a decline in developmental quotient, 6 were stable, and 2 patients had only a single data point. No dose group showed a clearly different response pattern. CONCLUSIONS: rhHNS administration via IDDD appeared generally safe and well tolerated. Treatment resulted in consistent declines in CSF heparan sulfate, suggesting in vivo activity in the relevant anatomical compartment. Results of this small study should be interpreted with caution. Future studies are required to assess the potential clinical benefits of rhHNS and to test improved IDDD models.


Assuntos
Heparitina Sulfato/líquido cefalorraquidiano , Mucopolissacaridose III/tratamento farmacológico , Sulfatases/administração & dosagem , Adolescente , Anticorpos/sangue , Anticorpos/líquido cefalorraquidiano , Criança , Pré-Escolar , Relação Dose-Resposta a Droga , Feminino , Humanos , Injeções Espinhais/instrumentação , Masculino , Mucopolissacaridose III/líquido cefalorraquidiano , Sulfatases/efeitos adversos , Sulfatases/imunologia , Resultado do Tratamento , Adulto Jovem
5.
Mol Genet Metab ; 114(4): 594-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25770355

RESUMO

The Sanfilippo Behavior Rating Scale (SBRS), a 68 item questionnaire, has been developed to assess the behavioral phenotype of children with Sanfilippo syndrome and its progression over time. Fifteen scales rate orality, movement/activity, attention/self-control, emotional function including anger and fear, and social interaction. Items within scales intercorrelate; measures of internal consistency are adequate. Twelve scales are grouped into 4 abnormality clusters: Movement, Lack of fear, Social/emotional and Executive Dysfunction. A Loess age-trajectory analysis showed that Lack of Fear, Social/Emotional and Executive Dysfunction increased steadily with age; Orality and Mood/Anger/Aggression leveled off. Movement peaked around 6years, then declined as children's excessive/purposeless actions stopped. Compared with standard scales, SBRS Movement was appropriately associated with the Vineland Motor scale; SBRS Lack of Fear had significant associations with the Autism Diagnostic Observation Schedule (ADOS), indicating a symptom overlap between Sanfilippo syndrome and autism. This suggests that reduced fearfulness may be the most salient/sensitive SBRS marker of disease progression. Volumetric MRI showed that increased Lack of Fear was significantly associated with reduced amygdala volume, consistent with our hypothesis that the behavior seen in Sanfilippo syndrome is a variant of Klüver-Bucy syndrome. Hippocampal volume loss had twice the effect on Social-Emotional Dysfunction as amygdala loss, consistent with a hippocampal role in attachment and social emotions. In conclusion, the SBRS assesses the Sanfilippo behavioral phenotype; it can measure behavior change that accompanies disease progression and/or results from treatment.


Assuntos
Escala de Avaliação Comportamental , Comportamento , Mucopolissacaridose III/psicologia , Adolescente , Tonsila do Cerebelo/patologia , Transtorno Autístico/diagnóstico , Transtorno Autístico/psicologia , Criança , Pré-Escolar , Medo , Feminino , Humanos , Lactente , Masculino , Mucopolissacaridose III/diagnóstico , Mucopolissacaridose III/patologia , Neuroimagem , Fenótipo , Comportamento Social , Inquéritos e Questionários
6.
JIMD Rep ; 13: 129-37, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24190801

RESUMO

OBJECTIVES: (1) Develop a methodology for obtaining reliable cognitive and developmental data in children with neurodegenerative disease and cognitive impairment and in turn monitor disease state and treatment outcomes. (2) Demonstrate validity of age-equivalent scores. METHODS: We present guidelines for obtaining accurate test scores in low-functioning and behaviorally disruptive pediatric patients, followed by a method validation study: (1) using disease-specific protocols to assess salient aspects of the known phenotype, (2) selecting appropriate tests, (3) managing behavior, and (4) using age-equivalent scores on standardized tools. We used the Bayley Scales of Infant Development-III or Kaufman Assessment Battery for Children-II with a group of 25 children with mucopolysaccharidosis type IIIA (MPS IIIA or Sanfilippo syndrome type A) with dementia. To demonstrate concurrent validity, we used the Vineland Adaptive Behavior Scales-II, comparing parent-reported age-equivalent scores (AEs) with those of the cognitive measures. RESULTS: We were successful in obtaining cognitive age-equivalents for 25 patients with MPS IIIA including those with severe behavioral disruption and a correlation of 0.95 was obtained comparing scores on the parent measure with cognitive age-equivalents validating the age-equivalent approach. CONCLUSION: An approach to the assessment of severely impaired children including those with behavioral disruption was implemented and is applicable to children with other severe neurological diseases. This approach will enhance the assessment of disease progression and monitoring of treatment outcome in clinical trials.

7.
J Allergy Clin Immunol ; 130(1): 145-54.e9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22677045

RESUMO

BACKGROUND: In subjects with psoriasis, inflammation and epidermal hyperplasia are thought to be controlled by T cell-derived cytokines. Evidence suggests that the T(H)17 cell cytokine IL-17A (IL-17) might play a role in disease pathogenesis. OBJECTIVE: We sought to understand the effect that neutralization of IL-17 has on the clinical features of psoriasis and to understand the role that IL-17 has in inflammatory pathways underlying psoriasis in human subjects. METHODS: We examined skin lesions obtained from 40 subjects participating in a phase I, randomized, double-blind, placebo-controlled trial of the anti-IL-17 mAb ixekizumab (previously LY2439821) in which subjects received 5, 15, 50, or 150 mg of subcutaneous ixekizumab or placebo at weeks 0, 2, and 4. RESULTS: There were significant dose-dependent reductions from baseline in keratinocyte proliferation, hyperplasia, epidermal thickness, infiltration into the dermis and epidermis by T cells and dendritic cells, and keratinocyte expression of innate defense peptides at 2 weeks. By week 6, the skin appeared normal. Quantitative RT-PCR and microarrays revealed an ablation of the disease-defining mRNA expression profile by 2 weeks after the first dose of study drug. The effect of IL-17 blockade on expression of genes synergistically regulated by IL-17 and TNF-α was of higher magnitude at 2 weeks than in prior studies with TNF-α antagonism. CONCLUSION: Our data suggest that IL-17 is a key "driver" cytokine that activates pathogenic inflammation in subjects with psoriasis. Neutralizing IL-17 with ixekizumab might be a successful therapeutic strategy in psoriasis.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Interleucina-17/metabolismo , Psoríase/fisiopatologia , Psoríase/terapia , Células Th17/imunologia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/imunologia , Relação Dose-Resposta a Droga , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-17/genética , Interleucina-17/imunologia , Ativação Linfocitária , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Psoríase/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/imunologia , Pele/metabolismo , Pele/fisiopatologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
8.
Immunology ; 136(1): 96-102, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22269018

RESUMO

Natural killer T (NKT) cells are a heterogeneous population of lymphocytes that recognize antigens presented by CD1d and have attracted attention because of their potential role linking innate and adaptive immune responses. Peripheral NKT cells display a memory-activated phenotype and can rapidly secrete large amounts of pro-inflammatory cytokines upon antigenic activation. In this study, we evaluated NKT cells in the context of patients co-infected with HIV-1 and Mycobacterium leprae. The volunteers were enrolled into four groups: 22 healthy controls, 23 HIV-1-infected patients, 20 patients with leprosy and 17 patients with leprosy and HIV-1-infection. Flow cytometry and ELISPOT assays were performed on peripheral blood mononuclear cells. We demonstrated that patients co-infected with HIV-1 and M. leprae have significantly lower NKT cell frequencies [median 0.022%, interquartile range (IQR): 0.007-0.051] in the peripheral blood when compared with healthy subjects (median 0.077%, IQR: 0.032-0.405, P < 0.01) or HIV-1 mono-infected patients (median 0.072%, IQR: 0.030-0.160, P < 0.05). Also, more NKT cells from co-infected patients secreted interferon-γ after stimulation with DimerX, when compared with leprosy mono-infected patients (P = 0.05). These results suggest that NKT cells are decreased in frequency in HIV-1 and M. leprae co-infected patients compared with HIV-1 mono-infected patients alone, but are at a more activated state. Innate immunity in human subjects is strongly influenced by their spectrum of chronic infections, and in HIV-1-infected subjects, a concurrent mycobacterial infection probably hyper-activates and lowers circulating NKT cell numbers.


Assuntos
Coinfecção/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Hanseníase/imunologia , Mycobacterium leprae , Células T Matadoras Naturais/imunologia , Adulto , Feminino , Infecções por HIV/complicações , Humanos , Hanseníase/complicações , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
J Drugs Dermatol ; 9(11): 1373-82, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21061760

RESUMO

Lepromatous leprosy is a model of immune evasion wherein pathogen-specific IL-10-secreting T cells and concomitant failure of Th-1 immunity permit uncontrolled proliferation of the intracellular pathogen, Mycobacterium leprae (M. leprae). The mechanism of this immune escape is unknown. Here, the authors report that phenolic glycolipid-1 (PGL-1), a major and distinguishing feature of the M. leprae cell wall, is expressed in the cell membrane of M. leprae-infected human dendritic cells, where it can activate complement in human serum. The authors demonstrate that PGL-1 and the C3 component of complement colocalize in lipid rafts in the dendritic cell membrane, and enter the immune synapse upon co-culture of M. leprae-infected DCs and T cells. Hence, activated C3 is strategically located to costimulate naïve T cells via the complement regulatory protein, CD46, a process known to stimulate the differentiation of IL-10-secreting regulatory T cells. These observations suggest a potential novel mechanism of immune evasion, wherein M. leprae may subvert host natural immunity to provoke an adaptive response that favors bacillary survival.


Assuntos
Hanseníase/imunologia , Mycobacterium leprae/imunologia , Imunidade Adaptativa , Antígenos de Bactérias/metabolismo , Ativação do Complemento , Complemento C3/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Glicolipídeos/metabolismo , Humanos , Interleucina-10/metabolismo , Mycobacterium leprae/metabolismo , Linfócitos T/imunologia
10.
Immunology ; 124(2): 206-14, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18284466

RESUMO

Leprosy and human immunodeficiency virus-1 (HIV-1) are examples of human infections where interactions between the pathogen and the host cellular immunity determine the clinical manifestations of disease. Hence, a significant immunopathological interaction between HIV-1 and leprosy might be expected. In the present study we explored several aspects of cellular immunity in patients co-infected with HIV-1 and Mycobacterium leprae. Twenty-eight individuals were studied, comprising four groups: healthy controls, HIV-1 and M. leprae co-infection, HIV-1 mono-infection, and M. leprae mono-infection. Subjects in the mono-infection and co-infection groups were matched as far as possible for bacillary load and HIV disease status, as appropriate. Peripheral blood mononuclear cells (PBMC) were analysed using six- and seven-colour flow cytometry to evaluate T-cell subpopulations and their activation status, dendritic cell (DC) distribution phenotypes and expression of IL-4 by T cells. The co-infected group exhibited lower CD4 : CD8 ratios, higher levels of CD8(+) T-cell activation, increased V delta : V delta 2 T cell ratios and decreased percentages of plasmacytoid DC, compared with HIV-1 mono-infected subjects. Across infected groups, IL-4 production by CD4(+) T lymphocytes was positively correlated with the percentage of effector memory CD4(+) T cells, suggesting antigenically driven differentiation of this population of T cells in both HIV-1 and M. leprae infections. Co-infection with M. leprae may exacerbate the immunopathology of HIV-1 disease. A T helper 2 (Th2) bias in the CD4(+) T-cell response was evident in both HIV-1 infection and leprosy, but no additive effect was apparent in co-infected patients.


Assuntos
Infecções por HIV/complicações , HIV-1 , Hanseníase/complicações , Adulto , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/imunologia , Células Dendríticas/imunologia , Feminino , Infecções por HIV/imunologia , HIV-1/isolamento & purificação , Humanos , Imunidade Celular , Interleucina-4/biossíntese , Hanseníase/imunologia , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Subpopulações de Linfócitos T/imunologia , Carga Viral
11.
Clin Infect Dis ; 44(3): e25-7, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17205432

RESUMO

We report a case of acquired immunodeficiency syndrome (AIDS)-associated, acyclovir-refractory genital herpes infection treated with topical imidazoquinoline therapy. The patient's plasmacytoid dendritic cells made a robust interferon- alpha response following in vitro stimulation with imidazoquinoline but not with herpes simplex virus. We hypothesize that disease resulting from defective herpes simplex virus-stimulated interferon- alpha may be overcome by stimulating intact alternative pathways.


Assuntos
Aminoquinolinas/uso terapêutico , Células Dendríticas/patologia , Infecções por HIV/imunologia , Herpes Genital/tratamento farmacológico , Indutores de Interferon/uso terapêutico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/virologia , Aciclovir/farmacologia , Adulto , Antivirais/farmacologia , Infecções por HIV/complicações , HIV-1/imunologia , Herpesvirus Humano 2/efeitos dos fármacos , Humanos , Imiquimode , Masculino
12.
J Immunol Methods ; 310(1-2): 86-99, 2006 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-16455104

RESUMO

We report a practical technique to assess peripheral blood dendritic cell (DC) maturation and function in whole blood (WB), which requires minimal blood volumes and minimizes ex vivo manipulations of clinical specimens. We determined optimal conditions for flow cytometric analysis of markers of DC maturation, including CCR7, CD25, CD80 and CD83, and of the intracellular cytokines, tumor necrosis factor-alpha (TNF-alpha) and interferon-alpha (IFN-alpha), in both myeloid (mDC) and plasmacytoid (pDC) lineages. We demonstrate concentration-dependent production of these cytokines by DC following short-term stimulation with ligands to Toll-like receptors (TLRs) 2/1, 3, 4, 7, 8 and 9. Kinetic studies revealed maximal TNF-alpha and IFN-alpha protein expression at 2 to 3 h after stimulation with certain TLR ligands. Finally, utilizing cells from a cohort of eight healthy donors, we compared DC responses to TLR activation in WB, freshly isolated peripheral blood mononuclear cells (PBMC) and cryopreserved PBMC. We found that TNF-alpha responses were essentially preserved, but IFN-alpha responses were profoundly diminished or entirely abrogated following cryopreservation. In conclusion, we propose that WB analysis of peripheral DC function is a rapid, reliable and simple method to evaluate TLR function in clinical specimens, which obviates artifact-prone cell purification. The major impact of cryopreservation on some DC responses further strengthens the case for a rapid method that uses fresh blood.


Assuntos
Células Dendríticas/imunologia , Leucócitos Mononucleares/imunologia , Receptores Toll-Like/imunologia , Adulto , Antígeno B7-1/imunologia , Citometria de Fluxo/métodos , Humanos , Imidazóis/imunologia , Interferon gama/imunologia , Ligantes , Lipopolissacarídeos/imunologia , Poli I-C/imunologia , Receptores CCR7 , Receptores de Quimiocinas/imunologia , Fator de Necrose Tumoral alfa/imunologia
13.
J Infect Dis ; 192(12): 2045-53, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16288366

RESUMO

The immunomodulatory drug thalidomide is the treatment of choice for erythema nodosum leprosum (ENL), an inflammatory cutaneous and systemic complication of multibacillary leprosy. To elucidate the mechanism of action of thalidomide in this syndrome, we prospectively investigated 20 patients with ENL who were treated with thalidomide for 21 days. All patients responded to treatment, with the majority of them having complete resolution of cutaneous lesions within 7 days. This response was associated with a marked but transient increase in ex vivo mitogen-induced expression of interleukin (IL)-2 and interferon- gamma by CD4(+) and CD8(+) T cells that was observed on treatment day 7, but these returned to pretreatment levels by day 21. Plasma tumor necrosis factor- alpha levels were not high at baseline, and they increased modestly during treatment. Plasma levels of IL-12 increased steadily during thalidomide treatment. Hence, the therapeutic effect of thalidomide in ENL appears to be associated with transient immune stimulation, which suggests that the drug may promote an active immunoregulatory response.


Assuntos
Eritema Nodoso/tratamento farmacológico , Eritema Nodoso/imunologia , Hanseníase Virchowiana/tratamento farmacológico , Hanseníase Virchowiana/imunologia , Talidomida/uso terapêutico , Adolescente , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Citocinas/sangue , Eritema Nodoso/patologia , Citometria de Fluxo , Expressão Gênica , Humanos , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Interferon gama/biossíntese , Hansenostáticos/farmacologia , Hansenostáticos/uso terapêutico , Hanseníase Virchowiana/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/patologia , Talidomida/farmacologia
14.
Front Biosci ; 10: 2955-65, 2005 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-15970549

RESUMO

Quantification of gene expression is important to confirm changes in levels of gene expression in disease. Prior quantification methods include standard curves, absolute quantification, and relative quantification. This paper describes an analytic method for the relative quantification of Presenilin-1 (PS-1) in neurons and Forkhead-box (FOX) p3 in PBMNCs using real-time PCR analytic techniques. A comparative Ct method (deltadelatCt) is described in which the quantity of target normalized to a normalizer gene reference is given by 2-deltadelatCt where deltadelatCt = [Ct of the gene of interest in the unknown specimen - Ct normalizer gene in the unknown specimen] - [Ct of the gene of interest in the calibrator specimen - Ct normalizer gene in the calibrator specimen]. The calibrator specimen is ideally from a non-treated control specimen and is analyzed on every assay plate with the unknown specimens of interest. The use of the deltadelatCt methodology allows for a higher throughput and a more economical approach to investigate gene expression. We applied this methodology to the quantification of PS-1 and FOXp3 genes and compare the levels of expression by normalizing to different normalizer genes using the deltadelatCt methodology. We find that use of GAPDH is the optimum normalizer gene for the genes analyzed in neurons from human brain and in PBMNCs.


Assuntos
Fatores de Transcrição Forkhead/sangue , Proteínas de Membrana/análise , Neurônios/metabolismo , Animais , Encéfalo/citologia , Expressão Gênica , Humanos , Presenilina-1 , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Ann N Y Acad Sci ; 1062: 79-94, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16461791

RESUMO

In humans, innate immune recognition of mycobacteria, including Mycobacterium tuberculosis and Mycobacterium leprae, involves toll-like receptor-2 (TLR-2), expressed on immature dendritic cells (DCs), and the T-cell gammadelta receptor expressed by a subpopulation of T cells that utilize Vdelta2 (Vdelta2 T cells). To investigate modulatory relationships between these host-cell populations in a microbial context, in vitro experiments were performed with human DCs and Vdelta2 T cells stimulated with model TLR-2 ligands and phosphoantigens, respectively. We observed that TLR-2-stimulated DCs enhanced interferon-gamma (IFN-gamma) production by Vdelta2 T cells; conversely, activated Vdelta2 T cells enhanced TLR-2-induced DC maturation via soluble factors including IFN-gamma, which costimulated interleukin-12 (IL-12) p70 secretion by DCs. Exposure of DCs to activated Vdelta2 T cells was critical for Th1 T-cell priming when TLR-2 stimulation was limiting. These results suggest that Vdelta2 T cells may play an adjuvant role in priming protective antimycobacterial immunity when TLR-2 stimulation is lacking, as may occur if the infectious inoculum is small, or if the pathogen is an intrinsically weak activator of DCs.


Assuntos
Comunicação Celular/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Imunidade Ativa , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Adulto , Diferenciação Celular/imunologia , Células Cultivadas , Técnicas de Cocultura , Células Dendríticas/citologia , Humanos , Ativação Linfocitária/imunologia , Mycobacterium leprae/imunologia , Mycobacterium tuberculosis/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptor 2 Toll-Like/imunologia , Receptor 2 Toll-Like/metabolismo , Receptor 2 Toll-Like/fisiologia
17.
J Immunol Methods ; 291(1-2): 185-95, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15345316

RESUMO

We optimized a whole blood intracellular cytokine assay to quantitate the frequency of specific CD4+ and CD8+ T cells in small volumes of whole blood from infants from developing countries. The assay is performed in two steps. First, whole blood is stimulated in the presence of specific antigens for 6-18 h, ending with cryopreservation of fixed white cells. These stimulation steps were specifically adapted to be practical and reliable in a rural, developing country field setting. Later, in a more resourceful setting, interferon-gamma producing CD4+ or CD8+ T cells are detected by flow cytometry. The assay proved sensitive and specific for detecting mycobacteria-specific immunity 10 weeks after Bacillus Calmette-Guerin (BCG) vaccination of newborns from a rural field site.


Assuntos
Citocinas/sangue , Espaço Intracelular/química , Subpopulações de Linfócitos T/citologia , Subpopulações de Linfócitos T/metabolismo , Vacina BCG/imunologia , Coleta de Amostras Sanguíneas , Criopreservação , Países em Desenvolvimento , Citometria de Fluxo , Infecções por HIV/sangue , Infecções por HIV/imunologia , Humanos , Memória Imunológica/imunologia , Lactente , Interferon gama/análise , Interferon gama/metabolismo , Mycobacterium tuberculosis/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Subpopulações de Linfócitos T/imunologia , Fatores de Tempo
18.
J Child Neurol ; 19(4): 250-7, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15163089

RESUMO

Childhood tuberculous meningitis is associated with serious long-term sequelae, including mental retardation, behavior disturbances, and motor handicap. Brain damage in tuberculous meningitis results from a cytokine-mediated inflammatory response, which causes vasculitis and obstructive hydrocephalus. Thalidomide, a potent tumor necrosis factor alpha inhibitor, was well tolerated and possibly showed some clinical benefit in children with tuberculous meningitis during a pilot study. The purpose of the present study was to assess the effect of adjunctive thalidomide in addition to standard antituberculosis and corticosteroid therapy on the outcome of tuberculous meningitis. Thalidomide (24 mg/kg/day orally) or placebo was administered in a double-blind randomized fashion for 1 month to patients with stage 2 or 3 tuberculous meningitis. The study was terminated early because all adverse events and deaths occurred in one arm of the study (thalidomide group). Thirty of the 47 children enrolled received adjunctive thalidomide, of whom 6 (20%) developed a skin rash, 8 (26%) hepatitis, and 2 (6%) neutropenia or thrombocytopenia. Four deaths (13%) occurred in patients with very severe neurologic compromise at baseline; two deaths were associated with a rash. Motor outcome after 6 months of antituberculosis therapy was similar in the two groups, even though the thalidomide group showed greater neurologic compromise on admission. In addition, the mean IQ of the two treatment groups did not differ significantly (mean IQ thalidomide group 57.8 versus mean IQ control group 67.5; P = .16). These results do not support the use of adjunctive high-dose thalidomide therapy in the treatment of tuberculous meningitis.


Assuntos
Imunossupressores/uso terapêutico , Talidomida/uso terapêutico , Tuberculose Meníngea/tratamento farmacológico , Corticosteroides/uso terapêutico , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Antituberculosos/uso terapêutico , Quimioterapia Adjuvante , Criança , Pré-Escolar , Estudos de Coortes , Coma/etiologia , Citocinas/sangue , Citocinas/líquido cefalorraquidiano , Método Duplo-Cego , Exantema/induzido quimicamente , Hepatite/etiologia , Humanos , Imunossupressores/efeitos adversos , Lactente , Inteligência/efeitos dos fármacos , Paresia/etiologia , África do Sul , Estatísticas não Paramétricas , Talidomida/efeitos adversos , Resultado do Tratamento , Tuberculose Meníngea/mortalidade
19.
J Infect Dis ; 188(2): 257-66, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12854081

RESUMO

To induce effector immunity, dendritic cells (DCs) must differentiate into fully mature cells. We show that, after human monocyte-derived DCs were infected with virulent Mycobacterium tuberculosis, up-regulation of cellular-surface maturation markers was minimal and reversible. In the presence of a potent stimulus for maturation (tumor necrosis factor [TNF]-alpha, interleukin [IL]-1beta, and prostaglandin E2 [PGE2]), M. tuberculosis inhibited phenotypic DC maturation. M. tuberculosis-infected DCs had an impaired ability to induce allogeneic lymphoproliferation and activated autologous memory CD4+ and CD8+ T cells optimally only in the presence of TNF-alpha, IL-1beta, and PGE2. Thus, virulent M. tuberculosis inhibits phenotypic and functional maturation of human monocyte-derived DCs. This mechanism, which has been described elsewhere for various viruses and for the virulent mycobacterium M. leprae, may be a novel mechanism that this pathogen uses to evade the host's immune response.


Assuntos
Células Dendríticas/citologia , Células Dendríticas/microbiologia , Monócitos/citologia , Monócitos/microbiologia , Mycobacterium tuberculosis/fisiologia , Biomarcadores , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular , Células Dendríticas/efeitos dos fármacos , Dinoprostona/farmacologia , Humanos , Memória Imunológica , Interleucina-1/farmacologia , Ativação Linfocitária , Fenótipo , Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/farmacologia
20.
J Infect Dis ; 187(6): 946-55, 2003 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-12660941

RESUMO

CD8(+) T cell immunity is critical for protection from viral disease, such as that caused by the human immunodeficiency virus (HIV) or cytomegalovirus (CMV). It is therefore important to identify therapies that can boost antiviral immunity. The recent finding that thalidomide acts as a T cell costimulator suggested that this drug may boost antiviral CD8(+) T cell responses. In this in vitro study, in a human autologous CD8(+) T cell/dendritic cell (DC) coculture system, thalidomide and a potent thalidomide analogue were shown to enhance virus-specific CD8(+) T cell cytokine production and cytotoxic activity. The drug-enhanced antiviral activity was noted in cells from both healthy donors and persons chronically coinfected with HIV and CMV. This stimulatory effect was directed at CD8(+) T cells, and not DCs. These results suggest an application for thalidomide and the thalidomide analogue as a novel immune-adjuvant therapy in chronic viral infections.


Assuntos
Adjuvantes Imunológicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Talidomida/farmacologia , Linfócitos T CD8-Positivos/imunologia , Divisão Celular/efeitos dos fármacos , Técnicas de Cocultura , Citocinas/análise , Citocinas/biossíntese , Infecções por Citomegalovirus/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Relação Dose-Resposta Imunológica , Citometria de Fluxo , Infecções por HIV/imunologia , Humanos , Técnicas de Imunoadsorção , Lenalidomida , Talidomida/análogos & derivados
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