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1.
Immunology ; 151(4): 385-394, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28342224

RESUMO

The study aimed to identify an immunoregulatory factor that restores the phosphoantigen response of Vγ9Vδ2+ T cells from HIV-positive individuals on antiretroviral therapy. It was designed to characterize the effects of interleukin-18 (IL-18) on proliferation and effector function in Vγ9Vδ2 T cells from HIV-negative individuals and test whether exogenous IL-18 reconstitutes the Vγ9Vδ2 T-cell response to phosphoantigen from HIV-positive donors. Vγ9Vδ2 T cells from HIV-negative individuals responded strongly to phosphoantigen or aminobisphosphonate stimulation of peripheral blood mononuclear cells (PBMC), whereas cells with similar T-cell receptor profiles from HIV-positive individuals only responded to aminobisphosphonate. Interleukin-18 was higher after aminobisphosphonate stimulation due to activation of the inflammasome pathway. Both IL-18 and IL-18 receptor levels were measured and the activity of exogenous IL-18 on HIV-negative and HIV-positive PBMC was evaluated in terms of Vγ9Vδ2 T-cell proliferation, memory subsets, cytokine expression and CD107a expression. Interleukin-18 stimulation increased proliferation, enhanced the accumulation of effector memory cells, and increased expression of cytotoxic markers in HIV-negative controls. When Vγ9Vδ2 T cells from HIV-positive individuals were stimulated with isopentenyl pyrophosphate in the presence of IL-18, there was increased proliferation, accumulation of memory cells, and higher expression of CD56, NKG2D and CD107a (markers of cytotoxic effector phenotype). Interleukin-18 stimulation specifically expanded the Vγ9-JγP+ subset of Vγ9Vδ2 T cells, as was expected for normal responses to phosphoantigen. Interleukin-18 is a potent stimulator of Vγ9Vδ2 T-cell proliferation and effector function. Therapies directed at reconstituting Vγ9Vδ2 T-cell activity in HIV-positive individuals should include stimulators of IL-18 or direct cytokine supplementation.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Imunoterapia/métodos , Interleucina-18/metabolismo , Células Matadoras Naturais/imunologia , Linfócitos T/imunologia , Antígenos/imunologia , Proliferação de Células , Células Cultivadas , Difosfonatos/metabolismo , Hemiterpenos/imunologia , Humanos , Imidazóis/metabolismo , Memória Imunológica , Imunofenotipagem , Ativação Linfocitária , Compostos Organofosforados/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/virologia , Ácido Zoledrônico
2.
Semin Thromb Hemost ; 38(8): 783-96, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23111861

RESUMO

The erythropoiesis-stimulating agents (ESAs) erythropoietin and darbepoetin prevent transfusions among chemotherapy-associated anemia patients. Clinical trials, meta-analyses, and guidelines identify mortality, tumor progression, and venous thromboembolism (VTE) risks with ESA administration in this setting. Product labels advise against administering ESAs with potentially curative chemotherapy (United States) or to conduct risk-benefit assessments (Europe/Canada). Since 2007, fewer chemotherapy-associated anemia patients in the United States and Europe receive ESAs. ESAs and the erythropoietin receptor agonist peginesatide prevent transfusions among chronic kidney disease (CKD) patients; clinical trials, guidelines, and meta-analyses demonstrate myocardial infarction, stroke, VTE, or mortality risks with ESAs targeting high hemoglobin levels. U.S. labels recommend administering ESAs or peginesatide at doses sufficient to prevent transfusions among dialysis CKD patients. For dialysis CKD patients, Canadian and European labels recommend targeting hemoglobin levels of 10 to 12 g/dL and 11 to 12 g/dL, respectively, with ESAs. ESA utilization for dialysis CKD patients has decreased in the United States.


Assuntos
Eritropoetina/análogos & derivados , Eritropoetina/uso terapêutico , Neoplasias/tratamento farmacológico , Peptídeos/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Darbepoetina alfa , Eritropoetina/efeitos adversos , Humanos , Peptídeos/efeitos adversos
3.
Clin Kidney J ; 5(1): 82-88, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22833806

RESUMO

BACKGROUND.: In 2006, nephrologists in Denmark unexpectedly identified chronic kidney disease (CKD) patients with a new syndrome, nephrogenic systemic fibrosis (NSF). Subsequently, 1603 NSF patients were reported to the Food and Drug Administration. Sixty hospitals in the USA account for 93% of these cases, and two hospitals in Denmark account for 4% of these reports. We review Denmark's identification and subsequent rapid eradication of NSF. METHODS.: NSF reports from clinicians, the Danish Medicines Agency (DMA) and gadolinium-based contrast agents (GBCAs) manufacturers were reviewed (2002-11). RESULTS.: In 1994, the DMA approved a non-ionic linear GBCA, gadodiamide (0.1 mmol/kg), for magnetic resonance imagings (MRIs), with a renal insufficiency contraindication. In 1996, 0.3 mmol/kg dosing received DMA approval. In 1998, the DMA removed renal contraindications. In 1997 and 2002, radiologists at Skejby Hospital and Herlev Hospital, respectively, began performing gadodiamide-enhanced magnetic resonance angiography scans (0.3 mmol/kg) of CKD patients. In 2005, Herlev clinicians requested assistance in evaluating etiological causes of NSF occurring among 10 CKD patients who had developed NSF. This investigation, focusing on infectious agents, was inconclusive. In 2006, Herlev clinicians reported that of 108 CKD patients who had received gadodiamide-enhanced MRI, 20 had developed probable NSF. Herlev radiologists voluntarily discontinued administering gadodiamide to all patients and no new NSF cases at Herlev Hospital developed subsequently. After meeting with Herlev radiologists, Skejby radiologists also discontinued administering gadodiamide to all patients. In 2007, the European Medicines Agency and the DMA contraindicated gadodiamide administration to CKD patients. In 2008, in response to these advisories, radiologists at the other 36 Danish hospitals discontinued administering gadodiamide to all patients, following on practices adopted at Skejby and Herlev Hospitals. In 2009, clinicians at Skejby Hospital reported that a look-back survey identified 33 CKD patients with NSF developing after undergoing GBCA-enhanced MRIs between 1999 and 2007. In 2010, an independent review, commissioned by the Minister of Health, concluded that the DMA had erred in rescinding gadodiamide's renal insufficiency contraindication in 1998 and that this error was a key factor in the development of NSF in Denmark. In 2011, three NSF cases associated with macrocyclic GBCA-associated NSF and three NSF patients with Stages 3 and 4 CKD disease from Skejby Hospital were reported. CONCLUSION.: A confluence of factors led to the development and eradication of NSF in Denmark.

4.
J Gen Intern Med ; 27(12): 1697-703, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22692632

RESUMO

Identification of serious adverse drug reactions (sADRS) associated with commonly used drugs can elude detection for years. Reye's syndrome (RS), nephrogenic systemic fibrosis (NSF), and pure red cell aplasia (PRCA) among chronic kidney disease (CKD) patients were recognized in 1951, 2000, and 1998, respectively. Reports associating these syndromes with aspirin, gadodiamide, and epoetin, were published 29, 6, and 4 years later, respectively. We obtained primary information from clinicians who identified causes of these sADRs and reviewed factors contributing to delayed identification of these toxicities. Overall, 3,500 aspirin-associated RS cases in the United States, 1,605 gadolinium-associated NSF cases, and 181 epoetin-associated PRCA cases were reported. Delays in FDA regulation of over-the- counter medications and administration of aspirin to children contributed to development of RS. For NSF, in 1996, the Danish Medicine Agency approved high-dose gadodiamide administration to chronic kidney disease (CKD) patients undergoing MR scans. Overall, 88 % of Danish NSF cases were from two hospitals and 97 % of United States' NSF cases were from 60 hospitals. These hospitals frequently administered high-doses of gadodiamide to CKD patients. Another factor was the decision to administer linear chelated contrast agents versus lower risk macrocyclic chelated agents. For PRCA, increased use of subcutaneous epoetin formulations to CKD patients, in part due to convenience and cost-savings considerations, and a European regulatory requirement requiring removal of albumin as a stabilizer, led to toxicity. Overall, 81, 13, and 17 years elapsed between drug introduction into practice and identification of a causal relationship for aspirin, erythropoietin, and gadodiamide, respectively. A substantial decline in new cases of these sADRs occurred within two years of identification of the offending drug. Clinicians should be vigilant for sADRs, even for frequently-prescribed pharmaceuticals, particularly in settings where formulation or regulatory changes have occurred, or when over-the-counter, off-label, or pediatric use is common.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/induzido quimicamente , Dermopatia Fibrosante Nefrogênica/induzido quimicamente , Aplasia Pura de Série Vermelha/induzido quimicamente , Síndrome de Reye/induzido quimicamente , Aspirina/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/fisiopatologia , Eritropoetina/efeitos adversos , Feminino , Gadolínio/efeitos adversos , Humanos , Masculino , Dermopatia Fibrosante Nefrogênica/epidemiologia , Dermopatia Fibrosante Nefrogênica/fisiopatologia , Prevalência , Prognóstico , Aplasia Pura de Série Vermelha/epidemiologia , Aplasia Pura de Série Vermelha/fisiopatologia , Síndrome de Reye/epidemiologia , Síndrome de Reye/fisiopatologia , Medição de Risco , South Carolina , Taxa de Sobrevida
5.
J Oncol Pract ; 8(6): e158-67, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23598851

RESUMO

PURPOSE: Pharmaceutical safety is a public health issue. In 2005, the Connecticut Attorney General (AG) raised concerns over adverse drug reactions in off-label settings, noting that thalidomide was approved to treat a rare illness, but more than 90% of its use was off label. A hematologist had reported thalidomide with doxorubicin or dexamethasone was associated with venous thromboembolism (VTE) rates of 25%. We review US Food and Drug Administration (FDA) and manufacturer responses to a citizen petition filed to address these thalidomide safety issues. METHODS: Case study. RESULTS: The AG petitioned the FDA requesting thalidomide-related safety actions. Coincidentally, the manufacturer submitted a supplemental New Drug Approval (sNDA), requesting approval to treat multiple myeloma with thalidomide-dexamethasone. FDA safety officers reviewed the petition and the literature and noted that VTE risks with thalidomide were not appropriately addressed in the existing package insert. In the sNDA application, the manufacturer reported thalidomide-associated toxicities for multiple myeloma were primarily somnolence and neurotoxicity, and a proposed package insert did not focus on VTE risks. In October, the FDA informed the Oncology Drug Division that VTE risks with thalidomide were poorly addressed in the existing label. After reviewing this memorandum, an Oncology Drug Division reviewer informed the manufacturer that approval of the sNDA would be delayed until several thalidomide-associated VTE safety actions, including revisions of the package insert, were implemented. The manufacturer and FDA agreed on these actions, and the sNDA was approved. CONCLUSION: New approaches addressing off-label safety are needed. The conditions that facilitated the successful response to this citizen petition are uncommon.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Uso Off-Label/legislação & jurisprudência , Talidomida/efeitos adversos , Pesquisa Translacional Biomédica/métodos , United States Food and Drug Administration , Connecticut , Aprovação de Drogas/legislação & jurisprudência , Indústria Farmacêutica/legislação & jurisprudência , Rotulagem de Medicamentos/legislação & jurisprudência , Hematologia , Humanos , Advogados , Manobras Políticas , Opinião Pública , Estados Unidos , Tromboembolia Venosa/induzido quimicamente
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