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1.
N Engl J Med ; 386(2): 138-147, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-34898140

RESUMO

Gene therapy with LentiGlobin for sickle cell disease (bb1111, lovotibeglogene autotemcel) consists of autologous transplantation of a patient's hematopoietic stem cells transduced with the BB305 lentiviral vector that encodes the ßA-T87Q-globin gene. Acute myeloid leukemia developed in a woman approximately 5.5 years after she had received LentiGlobin for sickle cell disease as part of the initial cohort (Group A) of the HGB-206 study. An analysis of peripheral-blood samples revealed that blast cells contained a BB305 lentiviral vector insertion site. The results of an investigation of causality indicated that the leukemia was unlikely to be related to vector insertion, given the location of the insertion site, the very low transgene expression in blast cells, and the lack of an effect on expression of surrounding genes. Several somatic mutations predisposing to acute myeloid leukemia were present after diagnosis, which suggests that patients with sickle cell disease are at increased risk for hematologic malignant conditions after transplantation, most likely because of a combination of risks associated with underlying sickle cell disease, transplantation procedure, and inadequate disease control after treatment. (Funded by Bluebird Bio.).


Assuntos
Anemia Falciforme/terapia , Expressão Gênica , Terapia Genética/efeitos adversos , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/etiologia , Globinas beta/genética , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/genética , Carcinogênese , Feminino , Vetores Genéticos , Humanos , Lentivirus , Fatores de Risco , Análise de Sequência de RNA , Transgenes , Transplante Autólogo
2.
N Engl J Med ; 386(5): 415-427, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34891223

RESUMO

BACKGROUND: Betibeglogene autotemcel (beti-cel) gene therapy for transfusion-dependent ß-thalassemia contains autologous CD34+ hematopoietic stem cells and progenitor cells transduced with the BB305 lentiviral vector encoding the ß-globin (ßA-T87Q) gene. METHODS: In this open-label, phase 3 study, we evaluated the efficacy and safety of beti-cel in adult and pediatric patients with transfusion-dependent ß-thalassemia and a non-ß0/ß0 genotype. Patients underwent myeloablation with busulfan (with doses adjusted on the basis of pharmacokinetic analysis) and received beti-cel intravenously. The primary end point was transfusion independence (i.e., a weighted average hemoglobin level of ≥9 g per deciliter without red-cell transfusions for ≥12 months). RESULTS: A total of 23 patients were enrolled and received treatment, with a median follow-up of 29.5 months (range, 13.0 to 48.2). Transfusion independence occurred in 20 of 22 patients who could be evaluated (91%), including 6 of 7 patients (86%) who were younger than 12 years of age. The average hemoglobin level during transfusion independence was 11.7 g per deciliter (range, 9.5 to 12.8). Twelve months after beti-cel infusion, the median level of gene therapy-derived adult hemoglobin (HbA) with a T87Q amino acid substitution (HbAT87Q) was 8.7 g per deciliter (range, 5.2 to 10.6) in patients who had transfusion independence. The safety profile of beti-cel was consistent with that of busulfan-based myeloablation. Four patients had at least one adverse event that was considered by the investigators to be related or possibly related to beti-cel; all events were nonserious except for thrombocytopenia (in 1 patient). No cases of cancer were observed. CONCLUSIONS: Treatment with beti-cel resulted in a sustained HbAT87Q level and a total hemoglobin level that was high enough to enable transfusion independence in most patients with a non-ß0/ß0 genotype, including those younger than 12 years of age. (Funded by Bluebird Bio; HGB-207 ClinicalTrials.gov number, NCT02906202.).


Assuntos
Produtos Biológicos/uso terapêutico , Terapia Genética/métodos , Globinas beta/genética , Talassemia beta/terapia , Adolescente , Adulto , Produtos Biológicos/efeitos adversos , Bussulfano/uso terapêutico , Criança , Transfusão de Eritrócitos/efeitos adversos , Eritropoese , Feminino , Vetores Genéticos , Genótipo , Hemoglobinas/análise , Humanos , Sobrecarga de Ferro/prevenção & controle , Lentivirus/genética , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/uso terapêutico , Talassemia beta/sangue , Talassemia beta/genética
3.
Nat Immunol ; 12(2): 167-77, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21217759

RESUMO

Mouse CCL8 is a CC chemokine of the monocyte chemoattractant protein (MCP) family whose biological activity and receptor usage have remained elusive. Here we show that CCL8 is highly expressed in the skin, where it serves as an agonist for the chemokine receptor CCR8 but not for CCR2. This distinguishes CCL8 from all other MCP chemokines. CCL8 responsiveness defined a population of highly differentiated, CCR8-expressing inflammatory T helper type 2 (T(H)2) cells enriched for interleukin (IL)-5. Ccr8- and Ccl8-deficient mice had markedly less eosinophilic inflammation than wild-type or Ccr4-deficient mice in a model of chronic atopic dermatitis. Adoptive transfer studies established CCR8 as a key regulator of T(H)2 cell recruitment into allergen-inflamed skin. In humans, CCR8 expression also defined an IL-5-enriched T(H)2 cell subset. The CCL8-CCR8 chemokine axis is therefore a crucial regulator of T(H)2 cell homing that drives IL-5-mediated chronic allergic inflammation.


Assuntos
Quimiocina CCL1/metabolismo , Quimiocina CCL8/metabolismo , Dermatite Atópica/imunologia , Pele/patologia , Células Th2/metabolismo , Transferência Adotiva , Animais , Sinalização do Cálcio/imunologia , Células Cultivadas , Quimiocina CCL1/genética , Quimiocina CCL1/imunologia , Quimiocina CCL8/genética , Quimiocina CCL8/imunologia , Quimiotaxia/genética , Quimiotaxia/imunologia , Clonagem Molecular , Modelos Animais de Doenças , Humanos , Interleucina-5/imunologia , Interleucina-5/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Retorno de Linfócitos/imunologia , Células Th2/imunologia , Células Th2/patologia
4.
Nat Immunol ; 11(6): 495-502, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20473299

RESUMO

Chemokines and other chemoattractants direct leukocyte migration and are essential for the development and delivery of immune and inflammatory responses. To probe the molecular mechanisms that underlie chemoattractant-guided migration, we did an RNA-mediated interference screen that identified several members of the synaptotagmin family of calcium-sensing vesicle-fusion proteins as mediators of cell migration: SYT7 and SYTL5 were positive regulators of chemotaxis, whereas SYT2 was a negative regulator of chemotaxis. SYT7-deficient leukocytes showed less migration in vitro and in a gout model in vivo. Chemoattractant-induced calcium-dependent lysosomal fusion was impaired in SYT7-deficient neutrophils. In a chemokine gradient, SYT7-deficient lymphocytes accumulated lysosomes in their uropods and had impaired uropod release. Our data identify a molecular pathway required for chemotaxis that links chemoattractant-induced calcium flux to exocytosis and uropod release.


Assuntos
Movimento Celular/fisiologia , Sinaptotagminas/metabolismo , Animais , Quimiocina CXCL12/metabolismo , Quimiotaxia , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase , Receptores CXCR4/metabolismo , Sinaptotagmina II/metabolismo , Sinaptotagminas/genética , Linfócitos T/imunologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-31061156

RESUMO

Infections caused by antibiotic-resistant Gram-negative bacteria expressing extended-spectrum ß-lactamases and carbapenemases are a growing global problem resulting in increased morbidity and mortality with limited treatment options. LYS228 is a novel intravenous monobactam antibiotic targeting penicillin binding protein 3 with potent activity against Enterobacteriaceae, including multidrug-resistant clinical isolates expressing serine and metallo-ß-lactamases. In this study, we evaluated the safety, tolerability, and pharmacokinetics of single and multiple intravenous doses of LYS228 in healthy volunteers. LYS228 was safe: no serious adverse events were reported. Adverse events, with the exception of catheter-related events, occurred sporadically, with similar incidences between LYS228 and placebo groups. No apparent adverse event-dose relationship was identified. LYS228 was not associated with any clinically significant dose-related hematologic, hepatic, or renal laboratory abnormalities. The most frequently observed adverse events were local injection site reactions, noted in 91.7% and 75.0% of subjects administered multiple doses of LYS228 and placebo, respectively. LYS228 demonstrated pharmacokinetic properties consistent with those of other ß-lactam antibiotics, with systemic exposures slightly greater than dose proportional, short terminal half-lives (between 1.0 and 1.6 h) with no significant accumulation, and rapid clearance predominantly through urinary excretion.


Assuntos
Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Monobactamas/efeitos adversos , Monobactamas/farmacocinética , Adulto , Antibacterianos/administração & dosagem , Proteínas de Bactérias/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/metabolismo , Feminino , Voluntários Saudáveis , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Monobactamas/administração & dosagem , beta-Lactamases/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-30061293

RESUMO

The monobactam scaffold is attractive for the development of new agents to treat infections caused by drug-resistant Gram-negative bacteria because it is stable to metallo-ß-lactamases (MBLs). However, the clinically used monobactam aztreonam lacks stability to serine ß-lactamases (SBLs) that are often coexpressed with MBLs. LYS228 is stable to MBLs and most SBLs. LYS228 bound purified Escherichia coli penicillin binding protein 3 (PBP3) similarly to aztreonam (derived acylation rate/equilibrium dissociation constant [k2/Kd ] of 367,504 s-1 M-1 and 409,229 s-1 M-1, respectively) according to stopped-flow fluorimetry. A gel-based assay showed that LYS228 bound mainly to E. coli PBP3, with weaker binding to PBP1a and PBP1b. Exposing E. coli cells to LYS228 caused filamentation consistent with impaired cell division. No single-step mutants were selected from 12 Enterobacteriaceae strains expressing different classes of ß-lactamases at 8× the MIC of LYS228 (frequency, <2.5 × 10-9). At 4× the MIC, mutants were selected from 2 of 12 strains at frequencies of 1.8 × 10-7 and 4.2 × 10-9 LYS228 MICs were ≤2 µg/ml against all mutants. These frequencies compared favorably to those for meropenem and tigecycline. Mutations decreasing LYS228 susceptibility occurred in ramR and cpxA (Klebsiella pneumoniae) and baeS (E. coli and K. pneumoniae). Susceptibility of E. coli ATCC 25922 to LYS228 decreased 256-fold (MIC, 0.125 to 32 µg/ml) after 20 serial passages. Mutants accumulated mutations in ftsI (encoding the target, PBP3), baeR, acrD, envZ, sucB, and rfaI These results support the continued development of LYS228, which is currently undergoing phase II clinical trials for complicated intraabdominal infection and complicated urinary tract infection (registered at ClinicalTrials.gov under identifiers NCT03377426 and NCT03354754).


Assuntos
Antibacterianos/farmacologia , Escherichia coli/enzimologia , Escherichia coli/genética , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Monobactamas/farmacologia , Aztreonam/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mutação/genética , beta-Lactamases/genética
7.
Bioorg Med Chem Lett ; 28(4): 748-755, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29336873

RESUMO

Metallo-ß-lactamases (MBLs), such as New Delhi metallo-ß-lactamase (NDM-1) have spread world-wide and present a serious threat. Expression of MBLs confers resistance in Gram-negative bacteria to all classes of ß-lactam antibiotics, with the exception of monobactams, which are intrinsically stable to MBLs. However, existing first generation monobactam drugs like aztreonam have limited clinical utility against MBL-expressing strains because they are impacted by serine ß-lactamases (SBLs), which are often co-expressed in clinical isolates. Here, we optimized novel monobactams for stability against SBLs, which led to the identification of LYS228 (compound 31). LYS228 is potent in the presence of all classes of ß-lactamases and shows potent activity against carbapenem-resistant isolates of Enterobacteriaceae (CRE).


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Monobactamas/farmacologia , Resistência beta-Lactâmica/efeitos dos fármacos , beta-Lactamases/metabolismo , Animais , Antibacterianos/efeitos adversos , Antibacterianos/química , Antibacterianos/metabolismo , Aztreonam/farmacologia , Células CHO , Cricetulus , Estabilidade de Medicamentos , Escherichia coli/efeitos dos fármacos , Feminino , Humanos , Meropeném , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monobactamas/efeitos adversos , Monobactamas/química , Monobactamas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Convulsões/induzido quimicamente , Relação Estrutura-Atividade , Tienamicinas/farmacologia
8.
Antimicrob Agents Chemother ; 60(10): 6207-15, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27503640

RESUMO

EDP-239, a novel hepatitis C virus (HCV) inhibitor targeting nonstructural protein 5A (NS5A), has been investigated in vitro and in vivo EDP-239 is a potent, selective inhibitor with potency at picomolar to nanomolar concentrations against HCV genotypes 1 through 6. In the presence of human serum, the potency of EDP-239 was reduced by less than 4-fold. EDP-239 is additive to synergistic with other direct-acting antivirals (DAAs) or host-targeted antivirals (HTAs) in blocking HCV replication and suppresses the selection of resistance in vitro Furthermore, EDP-239 retains potency against known DAA- or HTA-resistant variants, with half-maximal effective concentrations (EC50s) equivalent to those for the wild type. In a phase I, single-ascending-dose, placebo-controlled clinical trial, EDP-239 demonstrated excellent pharmacokinetic properties that supported once daily dosing. A single 100-mg dose of EDP-239 resulted in reductions in HCV genotype 1a viral RNA of >3 log10 IU/ml within the first 48 h after dosing and reductions in genotype 1b viral RNA of >4-log10 IU/ml within 96 h. (This study has been registered at ClinicalTrials.gov under identifier NCT01856426.).


Assuntos
Antivirais/farmacologia , Benzimidazóis/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Valina/análogos & derivados , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/farmacocinética , Carbamatos , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Farmacorresistência Viral/efeitos dos fármacos , Farmacorresistência Viral/genética , Quimioterapia Combinada , Feminino , Hepacivirus/genética , Humanos , Imidazóis/farmacologia , Masculino , Pirrolidinas , RNA Viral/sangue , Valina/farmacologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
9.
J Gastroenterol Hepatol ; 30(1): 184-91, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24995515

RESUMO

BACKGROUND AND AIMS: Albinterferon is a fusion of albumin and interferon-α2b developed to improve the pharmacokinetics, convenience, and potential efficacy of interferon-α for the treatment of chronic hepatitis infections. METHODS: This open-label, randomized, active-controlled, multicenter study investigated the safety and efficacy of albinterferon in patients with chronic hepatitis B virus (HBV) infection who were e-antigen (HBeAg) positive. One hundred and forty-one patients received one of four albinterferon doses/regimens or pegylated-interferon-α2a. Primary efficacy outcomes were changes in serum HBeAg and antibody, HBV-DNA, and alanine aminotransferase. Principal safety outcomes were changes in laboratory values, pulmonary function, and adverse events. RESULTS: The study was prematurely terminated as phase III trials in hepatitis C infection indicated noninferior efficacy but inferior safety compared with pegylated-interferon-α2a. Here, all treatment groups had a significant reduction in HBV-DNA from baseline. Reductions in HBV-DNA were not significantly different, except the 1200 µg every 4 weeks albinterferon dose which was inferior compared with pegylated-interferon-α2a. The serum alanine aminotransferase levels decreased in all arms. The per-patient incidence of adverse events was not significantly different for albinterferon (96.4-100%) and pegylated-interferon-α2a (93.1%). Total adverse events, however, were higher for albinterferon and correlated to dose. Decreased lung function was found in all arms (∼93% of patients), and was more common in some albinterferon groups. CONCLUSIONS: Albinterferon doses with similar anti-HBV efficacy to pegylated-interferon-α2a had higher rates of certain adverse events, particularly changes in lung diffusion capacity (http://www.clinicaltrials.gov number NCT00964665).


Assuntos
Albuminas/administração & dosagem , Antivirais/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Adulto , Alanina Transaminase/sangue , Albuminas/efeitos adversos , Antivirais/efeitos adversos , Biomarcadores/sangue , DNA Viral/sangue , Feminino , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/virologia , Humanos , Interferon-alfa/efeitos adversos , Masculino , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Resultado do Tratamento , Adulto Jovem
10.
Mol Ther Methods Clin Dev ; 31: 101155, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38074412

RESUMO

Ex vivo autologous hematopoietic stem cell lentiviral-based gene therapy with betibeglogene autotemcel has been studied in patients with transfusion-dependent ß-thalassemia in Phase III clinical trials (HGB-207 and HGB-212), with 90% of patients reaching transfusion independence (TI). Here, we explore manufacturing parameters, drug product quality attributes, and limited patient characteristics that had an impact on clinical efficacy in HGB-207 and HGB-212. Retrospective analysis revealed that the peripheral blood vector copy number (VCN) was related to TI, with a strong correlation between peripheral blood VCN at 6 months and gene therapy-derived therapeutic protein (HbAT87Q) expression at 6 months (correlation coefficient, 0.8681; p < 0.0001; R2 = 0.7536). A peripheral blood VCN threshold of ≥0.75 copies per diploid genome at 6 months post betibeglogene autotemcel infusion provided a stringent surrogate biomarker for TI and was used as the outcome variable for multivariate analysis using a random forest classifier. The top predictive feature of clinical efficacy was found to be the percentage of lentiviral vector-positive cells in the drug product. This retrospective analysis is critical to understanding the key product quality attributes that can predict clinical efficacy in lentiviral vector gene therapy within this clinical trial population.

11.
Proc Natl Acad Sci U S A ; 105(12): 4814-9, 2008 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-18347328

RESUMO

Cerebral malaria is a significant cause of global mortality, causing an estimated two million deaths per year, mainly in children. The pathogenesis of this disease remains incompletely understood. Chemokines have been implicated in the development of cerebral malaria, and the IFN-inducible CXCR3 chemokine ligand IP-10 (CXCL10) was recently found to be the only serum biomarker that predicted cerebral malaria mortality in Ghanaian children. We show that the CXCR3 chemokine ligands IP-10 and Mig (CXCL9) were highly induced in the brains of mice with murine cerebral malaria caused by Plasmodium berghei ANKA. Mice deficient in CXCR3 were markedly protected against cerebral malaria and had far fewer T cells in the brain compared with wild-type mice. In competitive transfer experiments, CXCR3-deficient CD8(+) T cells were 7-fold less efficient at migrating into the infected brains than wild-type CD8(+) T cells. Adoptive transfer of wild-type CD8(+) effector T cells restored susceptibility of CXCR3-deficient mice to cerebral malaria and also restored brain proinflammatory cytokine and chemokine production and recruitment of T cells, independent of CXCR3. Mice deficient in IP-10 or Mig were both partially protected against cerebral malaria mortality when infected with P. berghei ANKA. Brain immunohistochemistry revealed Mig staining of endothelial cells, whereas IP-10 staining was mainly found in neurons. These data demonstrate that CXCR3 on CD8(+) T cells is required for T cell recruitment into the brain and the development of murine cerebral malaria and suggest that the CXCR3 ligands Mig and IP-10 play distinct, nonredundant roles in the pathogenesis of this disease.


Assuntos
Quimiocina CXCL10/imunologia , Quimiocina CXCL9/imunologia , Malária Cerebral/imunologia , Malária Cerebral/patologia , Receptores CXCR3/imunologia , Animais , Encéfalo/parasitologia , Encéfalo/patologia , Complexo CD3/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/parasitologia , Movimento Celular , Quimiocina CXCL10/genética , Quimiocina CXCL9/genética , Ligantes , Malária Cerebral/parasitologia , Malária Cerebral/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmodium berghei/imunologia , Receptores de Citocinas/deficiência , Baço/metabolismo , Baço/patologia , Taxa de Sobrevida , Regulação para Cima/genética
12.
Clin Infect Dis ; 51(7): 813-22, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20738185

RESUMO

In this review, we collate 25 clinically useful human immunodeficiency virus (HIV)-related Web sites to facilitate efficient access to online resources according to themes of clinical inquiry: (1) comprehensive clinical information, (2) opportunistic infections, (3) antiretroviral drug interactions, (4) care of HIV-infected women and children, and (5) continuing medical education. We evaluated these Web sites for clinical content and quality using criteria including the currency of information, inclusion of references, sponsors, whether the site is useful in resource-limited settings, ease of navigation, and content specific for each theme. Using the specified criteria, we provided overall ratings for each Web site. We conclude that the Web sites listed in this review can help extend knowledge about best practices and provide real-time patient care support to clinicians.


Assuntos
Educação Médica Continuada/métodos , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infectologia/educação , Internet , Informática Médica/métodos , Infecções por HIV/epidemiologia , Humanos , Médicos
13.
Circ Res ; 102(2): 218-25, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17991878

RESUMO

Obese individuals often have low plasma adiponectin and concomitant chronic inflammation with a predisposition to metabolic and cardiovascular diseases. The present study reports a novel antiinflammatory action of adiponectin in human monocyte-derived macrophages (MPhi) suppressing T-lymphocyte accumulation in atherogenesis. RNA profiling of lipopolysaccharide-stimulated human MPhi identified CXC chemokine ligands (CXCLs), such as IP-10 (interferon [IFN]-inducible protein 10) (CXCL10), I-TAC (IFN-inducible T-cell alpha chemoattractant) (CXCL11), and Mig (monokine induced by IFN-gamma) (CXCL9), T-lymphocyte chemoattractants associated with atherogenesis, among the top 14 transcripts suppressed by adiponectin. Real-time quantitative RT-PCR and ELISA verified that adiponectin inhibited expression of these chemokines at both the mRNA and protein levels in a concentration-dependent manner. Adiponectin reduced the release by lipopolysaccharide-stimulated MPhi of chemoattractant activity for CXC chemokine receptor 3-transfected (receptor for IP-10, Mig, and I-TAC) lymphocytes. Adiponectin decreased lipopolysaccharide-inducible IP-10 promoter activity in promoter-transfected THP-1 MPhi but did not change IP-10 mRNA stability. In lipopolysaccharide-stimulated MPhi, reduction of IFN-beta by adiponectin preceded inhibition of IP-10 mRNA expression. Immunoblot and chromatin immunoprecipitation analyses demonstrated that adiponectin attenuated activation of the transcription factor IFN regulatory factor 3, involved in the MyD88-independent pathway of Toll-like receptor 4 signaling, and subsequent IFN regulatory factor 3 binding to IFN-beta promoter. In vivo studies further demonstrated that apolipoprotein E/adiponectin double-deficient (apoE-/-APN-/-) mice had increased plasma IP-10 levels, accelerated T-lymphocyte accumulation in atheromata, and augmented atherogenesis compared with apoE single-deficient (apoE-/-APN+/+) mice. This study establishes that low levels of adiponectin associated with obesity, the metabolic syndrome, and diabetes favor T-lymphocyte recruitment and contribute to adaptive immune response during atherogenesis.


Assuntos
Adiponectina/farmacologia , Arteriosclerose/imunologia , Quimiocinas CXC/antagonistas & inibidores , Quimiotaxia de Leucócito/efeitos dos fármacos , Receptores CXCR3/metabolismo , Linfócitos T/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus , Relação Dose-Resposta a Droga , Humanos , Imunidade/efeitos dos fármacos , Macrófagos , Síndrome Metabólica , Obesidade , Receptores CXCR3/genética , Transfecção
14.
Mol Cell Biol ; 26(15): 5838-49, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16847335

RESUMO

CXCR3 is a G-protein-coupled seven-transmembrane domain chemokine receptor that plays an important role in effector T-cell and NK cell trafficking. Three gamma interferon-inducible chemokines activate CXCR3: CXCL9 (Mig), CXCL10 (IP-10), and CXCL11 (I-TAC). Here, we identify extracellular domains of CXCR3 that are required for ligand binding and activation. We found that CXCR3 is sulfated on its N terminus and that sulfation is required for binding and activation by all three ligands. We also found that the proximal 16 amino acid residues of the N terminus are required for CXCL10 and CXCL11 binding and activation but not CXCL9 activation. In addition, we found that residue R216 in the second extracellular loop is required for CXCR3-mediated chemotaxis and calcium mobilization but is not required for ligand binding or ligand-induced CXCR3 internalization. Finally, charged residues in the extracellular loops contribute to the receptor-ligand interaction. These findings demonstrate that chemokine activation of CXCR3 involves both high-affinity ligand-binding interactions with negatively charged residues in the extracellular domains of CXCR3 and a lower-affinity receptor-activating interaction in the second extracellular loop. This lower-affinity interaction is necessary to induce chemotaxis but not ligand-induced CXCR3 internalization, further suggesting that different domains of CXCR3 mediate distinct functions.


Assuntos
Arginina/metabolismo , Quimiotaxia de Leucócito/fisiologia , Estrutura Secundária de Proteína , Receptores de Quimiocinas/química , Receptores de Quimiocinas/metabolismo , Proteínas Recombinantes/química , Tirosina/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Quimiocina CXCL10 , Quimiocina CXCL11 , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Humanos , Ligantes , Camundongos , Dados de Sequência Molecular , Peptídeos/genética , Peptídeos/metabolismo , Ligação Proteica , Processamento de Proteína Pós-Traducional , Receptores CXCR3 , Receptores de Quimiocinas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
15.
ACS Infect Dis ; 5(7): 1045-1051, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-30861342

RESUMO

Resistance in Gram-negative bacteria to ß-lactam drugs is mediated primarily by the expression of ß-lactamases, and co-dosing of ß-lactams with a ß-lactamase inhibitor (BLI) is a clinically proven strategy to address resistance. New ß-lactamases that are not impacted by existing BLIs are spreading and creating the need for development of novel broader spectrum BLIs. IID572 is a novel broad spectrum BLI of the diazabicyclooctane (DBO) class that is able to restore the antibacterial activity of piperacillin against piperacillin/tazobactam-resistant clinical isolates. IID572 is differentiated from other DBOs by its broad inhibition of ß-lactamases and the lack of intrinsic antibacterial activity.


Assuntos
Compostos Azabicíclicos/síntese química , Bactérias Gram-Negativas/efeitos dos fármacos , Inibidores de beta-Lactamases/síntese química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Compostos Azabicíclicos/química , Compostos Azabicíclicos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Estabilidade de Medicamentos , Bactérias Gram-Negativas/enzimologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Inibidores de beta-Lactamases/química , Inibidores de beta-Lactamases/farmacologia
16.
J Immunol Methods ; 331(1-2): 127-39, 2008 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-18206159

RESUMO

Trafficking of leukocytes to sites of inflammation is an important step in the establishment of an immune response. Chemokines are critical regulators of leukocyte trafficking and are widely studied molecules for their important role in disease and for their potential as new therapeutic targets. The ability of chemokines to induce leukocyte recruitment has been mainly measured by in vitro chemotaxis assays, which lack many components of the complex biological process of leukocyte migration and therefore provide incomplete information about chemokine function in vivo. In vivo assays to study the activity of chemokines to induce leukocyte recruitment have been difficult to establish. We describe here the development of a robust in vivo recruitment assay for CD8(+) and CD4(+) T lymphocytes induced by the CXCR3 ligands IP-10 (CXCL10) and I-TAC (CXCL11). For this assay, in vitro activated T lymphocytes were adoptively transferred into the peritoneum of naïve mice. Homing of these transferred T lymphocytes into the airways was measured following intratracheal instillation of chemokines. High recruitment indices were achieved that were dependent on chemokine concentration and CXCR3 expression on the transferred lymphocytes. Recruitment was also inhibited by antibodies to the chemokine. The assay models the natural condition of chemokine-mediated lymphocyte migration into the airways as chemokines are expressed in the airways during inflammation. The nature of this model allows flexibility to study wildtype and mutant chemokines and chemokine receptors and the ability to evaluate chemokine antagonists and antibodies in vivo. This assay will therefore help elucidate a deeper understanding of the chemokine system in vivo.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Quimiocinas CXC/metabolismo , Quimiotaxia de Leucócito , Receptores de Quimiocinas/metabolismo , Animais , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Quimiocinas CXC/imunologia , Inflamação/imunologia , Inflamação/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Quimiocinas/imunologia
17.
J Drug Assess ; 7(1): 66-74, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30370176

RESUMO

Objective: Infection with hepatitis C virus is the leading indication for liver transplantation and most common cause of infectious disease-related mortality in the United States. BZF961 is a novel inhibitor of the hepatitis C virus NS3-4A protease. Methods: This sequential, three part exploratory first-in-human study investigated the safety and pharmacokinetics of single and multiple ascending oral doses of BZF961 in healthy subjects. The first two parts were randomized, double-blind, placebo-controlled, time-lagged, single and multiple ascending oral dose segments. The third part analyzed the effect of ritonavir on BZF961 pharmacokinetics. Results: BZF961 was generally safe and well-tolerated in single and multiple oral doses in healthy subjects. There were no deaths and no serious adverse events. The most common adverse events were nausea and other gastrointestinal symptoms. Co-administration of ritonavir with BZF961 was well tolerated and increased BZF961 exposure by up to 60-fold, as well as reduced the overall exposure variability. Conclusions: BZF961 was generally safe and well-tolerated and its exposure was boosted by the co-administration of ritonavir.

19.
Clin Ther ; 40(9): 1567-1581.e4, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30185394

RESUMO

PURPOSE: Infection with hepatitis C virus is the leading cause of infectious disease mortality in the United States. BZF961 is a novel small molecule inhibitor of the hepatitis C virus NS3-4A protease. Here we present the results of a randomized, double-blinded, placebo-controlled, multicentered study in treatment-naïve patients with chronic hepatitis C virus genotype-1 infection. METHODS: Patients were enrolled sequentially in 2 parts and treated for 3days. BZF961 was administered as monotherapy (500mg BID for 3 days) or in combination with the cytochrome P450 3A4 inhibitor ritonavir to boost its exposure (BZF961 10, 20, or 50mg QD or BID). FINDINGS: BZF961 was safe and well tolerated in the patients studied with no serious adverse events. There were no appreciable differences in adverse events among patients who received BZF961, BZF961 with ritonavir, or placebo. There was a significant, clinically meaningful reduction in viral load from baseline in patients treated either with BZF961 500mg every 12hours alone or BZF961 50mg every 12hours in combination with ritonavir. Activity against the hepatitis C virus of the lower-dose regimens was apparent but more modest. There were no relevant changes from baseline viral loads in placebo-treated patients. IMPLICATIONS: Coadministration of ritonavir with BZF961 boosted BZF961 exposure (including Cmin, which is the clinically relevant parameter associated with antiviral activity) in a therapeutic range with less variability compared with BZF961 alone. For strategic reasons, BZF961 is no longer under development.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Compostos Orgânicos/uso terapêutico , Ritonavir/uso terapêutico , Adulto , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/genética , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Orgânicos/administração & dosagem , Compostos Orgânicos/efeitos adversos , Estados Unidos , Carga Viral/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores
20.
World J Gastroenterol ; 23(42): 7626-7634, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29204062

RESUMO

AIM: To characterize the understanding of hepatitis B virus (HBV) and determine if outreach improves HBV understanding among Greater Boston Area immigrants. METHODS: Six outreach sessions were held in various community venues in the Greater Boston Area. Verbal consent was obtained from participants prior to starting each session. Each session included a pre-session questionnaire, followed by a teaching session, and then a post-session questionnaire. In person interpreters were present for translation during the teaching session and assistance for questionnaire completion when needed. The questions were developed based on the HBV clinical experience of physicians who serve largely immigrant populations. Questionnaires included Likert-type scale, open-ended, and true-false questions. All results were anonymous. RESULTS: One hundred and one people participated in this study. Participants were 30% male with ages ranging from 19 to 87 years. The study population included immigrants from 21 countries, as well as seven United States-born participants. The greatest numbers of participants were from Somalia (44%), Morocco (10%), and Cameroon (8%). Pre session questionnaires revealed that 42% of participants were unaware that HBV can cause cancer, and 50% were unaware that therapies for HBV exist. Our brief teaching intervention led to improved scores on post session questionnaires. For example, at baseline, 58% of participants responded correctly to the question "HBV infection can cause scarring of the liver and liver cancer", whereas 79% of participants responded correctly after the teaching session (P = 0.01). Furthermore, the mean of total correct answers in the true or false portion of the questionnaire increased from 5.5 to 7.6 (P < 0.001). CONCLUSION: A teaching session targeting Boston Immigrants at-risk for HBV helped improve scores on HBV knowledge questionnaires. Outreach may empower at-risk patients to pro-actively seek HBV care.


Assuntos
Emigrantes e Imigrantes , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Hepatite B , Adulto , Boston , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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