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INTRODUCTION: Cancer treatment planning in older adults is complex and requires careful balancing of survival, quality of life benefits, and risk of treatment-related morbidity and toxicity. As a result, treatment selection in this cohort tends to differ from that for younger patients. However, there are very few studies describing cancer treatment patterns in older cohorts. METHODS: We used data from the ASPirin in Reducing Events in the Elderly (ASPREE) trial and the ASPREE Cancer Treatment Substudy (ACTS) to describe cancer treatment patterns in older adults. We used a multivariate logistic regression model to identify factors affecting receipt of treatment. RESULTS: Of 1893 eligible Australian and United States (US) participants with incident cancer, 1569 (81%) received some form of cancer treatment. Non-metastatic breast cancers most frequently received treatment (98%), while haematological malignancy received the lowest rates of treatment (60%). Factors associated with not receiving treatment were older age (OR 0.94, 95% CI 0.91-0.96), residence in the US (OR 0.34, 95% CI 0.22-0.54), smoking (OR 0.57, 95% CI 0.40-0.81), and diabetes (OR 0.56, 95% CI 0.39-0.80). After adjustment for treatment patterns in sex-specific cancers, sex did not impact receipt of treatment. CONCLUSIONS: This study is one of the first describing cancer treatment patterns and factors affecting receipt of treatment across common cancer types in older adults. We found that most older adults with cancer received some form of cancer treatment, typically surgery or systemic therapy, although this varied by factors such as cancer type, age, sex, and country of residence.
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BACKGROUND: ASPirin in Reducing Events in the Elderly, a randomized, double-blind, placebo-controlled trial of daily low-dose aspirin (100 mg) in older adults, showed an increase in all-cause mortality, primarily due to cancer. In contrast, prior randomized controlled trials, mainly involving younger individuals, demonstrated a delayed cancer benefit with aspirin. We now report a detailed analysis of cancer incidence and mortality. METHODS: 19 114 Australian and US community-dwelling participants aged 70 years and older (US minorities 65 years and older) without cardiovascular disease, dementia, or physical disability were randomly assigned and followed for a median of 4.7 years. Fatal and nonfatal cancer events, a prespecified secondary endpoint, were adjudicated based on clinical records. RESULTS: 981 cancer events occurred in the aspirin and 952 in the placebo groups. There was no statistically significant difference between groups for all incident cancers (hazard ratio [HR] = 1.04, 95% confidence interval [CI] = 0.95 to 1.14), hematological cancer (HR = 0.98, 95% CI = 0.73 to 1.30), or all solid cancers (HR = 1.05, 95% CI = 0.95 to 1.15), including by specific tumor type. However, aspirin was associated with an increased risk of incident cancer that had metastasized (HR = 1.19, 95% CI = 1.00 to 1.43) or was stage 4 at diagnosis (HR = 1.22, 95% CI = 1.02 to 1.45), and with higher risk of death for cancers that presented at stages 3 (HR = 2.11, 95% CI = 1.03 to 4.33) or 4 (HR = 1.31, 95% CI = 1.04 to 1.64). CONCLUSIONS: In older adults, aspirin treatment had an adverse effect on later stages of cancer evolution. These findings suggest that in older persons, aspirin may accelerate the progression of cancer and, thus, suggest caution with its use in this age group.
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Aspirina/administração & dosagem , Neoplasias/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/administração & dosagem , Austrália/epidemiologia , Feminino , Humanos , Incidência , Masculino , Mortalidade , Neoplasias/mortalidade , Modelos de Riscos Proporcionais , Ensaios Clínicos Controlados Aleatórios como Assunto , Estados Unidos/epidemiologiaRESUMO
Nelfinavir is an HIV protease inhibitor being repurposed as an anti-cancer agent in preclinical models and in small oncology trials, yet the MTD of nelfinavir has not been determined. Therefore, we conducted a Phase Ia study to establish the maximum tolerated dose (MTD) and dose limiting toxicities (DLT) of nelfinavir in subjects with advanced solid tumors. Adults with refractory cancers were given oral nelfinavir twice daily with pharmacokinetic and pharmacodynamic analyses. Twenty-eight subjects were enrolled. Nelfinavir was generally well tolerated. Common adverse events included diarrhea, anemia, and lymphopenia, which were mostly mild. The DLT was rapid-onset neutropenia that was reversible. The MTD was established at 3125 mg twice daily. In an expansion cohort at the MTD, one of 11 (9%) evaluable subjects had a confirmed partial response. This, plus two minor responses, occurred in subjects with neuroendocrine tumors of the midgut or pancreatic origin. Thirty-six percent of subjects had stable disease for more than 6 months. In peripheral blood mononuclear cells, Nelfinavir inhibited AKT and induced markers of ER stress. In summary, nelfinavir is well tolerated in cancer patients at doses 2.5 times the FDA-approved dose for HIV management and showed preliminary activity in tumors of neuroendocrine origin.
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Antineoplásicos/uso terapêutico , Inibidores da Protease de HIV/uso terapêutico , Nelfinavir/uso terapêutico , Neoplasias/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Esquema de Medicação , Feminino , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/efeitos adversos , Inibidores da Protease de HIV/farmacocinética , Humanos , Masculino , Maryland , Dose Máxima Tolerável , Pessoa de Meia-Idade , Nelfinavir/administração & dosagem , Nelfinavir/efeitos adversos , Nelfinavir/farmacocinética , Neoplasias/patologia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto JovemRESUMO
The success of adoptive T cell gene transfer for treatment of cancer and HIV is predicated on generating a response that is both durable and safe. We report long-term results from three clinical trials to evaluate gammaretroviral vector-engineered T cells for HIV. The vector encoded a chimeric antigen receptor (CAR) composed of CD4 linked to the CD3ζ signaling chain (CD4ζ). CAR T cells were detected in 98% of samples tested for at least 11 years after infusion at frequencies that exceeded average T cell levels after most vaccine approaches. The CD4ζ transgene retained expression and function. There was no evidence of vector-induced immortalization of cells; integration site distributions showed no evidence of persistent clonal expansion or enrichment for integration sites near genes implicated in growth control or transformation. The CD4ζ T cells had stable levels of engraftment, with decay half-lives that exceeded 16 years, in marked contrast to previous trials testing engineered T cells. These findings indicate that host immunosuppression before T cell transfer is not required to achieve long-term persistence of gene-modified T cells. Further, our results emphasize the safety of T cells modified by retroviral gene transfer in clinical application, as measured in >500 patient-years of follow-up. Thus, previous safety issues with integrating viral vectors are hematopoietic stem cell or transgene intrinsic, and not a general feature of retroviral vectors. Engineered T cells are a promising form of synthetic biology for long-term delivery of protein-based therapeutics. These results provide a framework to guide the therapy of a wide spectrum of human diseases.
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Transferência Adotiva/efeitos adversos , Técnicas de Transferência de Genes , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Recombinantes/imunologia , Retroviridae/genética , Linfócitos T/imunologia , Linfócitos T/transplante , Complexo CD3/metabolismo , Antígenos CD4/metabolismo , Estudos de Coortes , Epigênese Genética , Seguimentos , Vetores Genéticos/genética , Genômica , Meia-Vida , Humanos , Interleucina-2/administração & dosagem , Interleucina-2/imunologia , Mutagênese Insercional/genética , Receptores de Antígenos de Linfócitos T/genética , Proteínas Recombinantes/genética , Linfócitos T/metabolismo , Fatores de Tempo , Transcrição Gênica , Transgenes/genéticaRESUMO
Hemophagocytic lymphohistiocytosis (HLH) is an immune disorder characterized by cytokine dysregulation and uncontrolled activation of T lymphocytes and macrophages. It is categorized as primary when associated with specific genetic mutations or secondary when associated with infections, malignancies, or autoimmune disorders. Clinical features of HLH include unexplained fever, hepatosplenomegaly, pancytopenia, and severe hyperferritinemia. Treatment of primary HLH has become standardized based on the HLH-2004 protocol using cyclosporine, etoposide, and dexamethasone with or without intrathecal methotrexate followed by hematopoietic stem cell transplantation. Treatment of secondary HLH is directed at control of the underlying condition. If unsuccessful, cytotoxic agents such as those in HLH-2004, steroids, intravenous γ-globulin, or targeted immune therapy have been used. Immunotherapy targeting CD52 expressed on immune effector cells of HLH is a rational therapeutic approach in patients too ill for traditional cytotoxic chemotherapy. We describe the successful use of alemtuzumab to treat HLH due to systemic lupus erythematosus.
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Anticorpos Monoclonais Humanizados/administração & dosagem , Lúpus Eritematoso Sistêmico/complicações , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Alemtuzumab , Anti-Infecciosos/administração & dosagem , Antirreumáticos/administração & dosagem , Quimioterapia Combinada , Feminino , Glucocorticoides/administração & dosagem , Humanos , Hidroxicloroquina/administração & dosagem , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/etiologia , Pessoa de Meia-Idade , Prednisona/administração & dosagemRESUMO
BACKGROUND: Cutaneous Leishmania major has affected many travelers including military personnel in Iraq and Afghanistan. Optimal treatment for this localized infection has not been defined, but interestingly the parasite is thermosensitive. METHODOLOGY/PRINCIPAL FINDINGS: Participants with parasitologically confirmed L. major infection were randomized to receive intravenous sodium stibogluconate (SSG) 20mg/kg/day for ten doses or localized ThermoMed (TM) device heat treatment (applied at 50 degrees C for 30 seconds) in one session. Those with facial lesions, infection with other species of Leishmania, or more than 20 lesions were excluded. Primary outcome was complete re-epithelialization or visual healing at two months without relapse over 12 months. Fifty-four/56 enrolled participants received intervention, 27 SSG and 27 TM. In an intent to treat analysis the per subject efficacy at two months with 12 months follow-up was 54% SSG and 48% TM (p = 0.78), and the per lesion efficacy was 59% SSG and 73% TM (p = 0.053). Reversible abdominal pain/pancreatitis, arthralgias, myalgias, headache, fatigue, mild cytopenias, and elevated transaminases were more commonly present in the SSG treated participants, whereas blistering, oozing, and erythema were more common in the TM arm. CONCLUSIONS/SIGNIFICANCE: Skin lesions due to L. major treated with heat delivered by the ThermoMed device healed at a similar rate and with less associated systemic toxicity than lesions treated with intravenous SSG. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT 00884377.
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Gluconato de Antimônio e Sódio/uso terapêutico , Hipertermia Induzida , Leishmania major/efeitos dos fármacos , Leishmania major/efeitos da radiação , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/terapia , Adolescente , Adulto , Animais , Gluconato de Antimônio e Sódio/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemAssuntos
Carcinoma/patologia , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/secundário , Neoplasias da Próstata/patologia , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Diagnóstico Diferencial , Evolução Fatal , Humanos , Masculino , Neoplasias Meníngeas/líquido cefalorraquidiano , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológicoRESUMO
The PI3K/Akt/mTOR pathway is a prototypic survival pathway that is constitutively activated in many types of cancer. Mechanisms for pathway activation include loss of tumor suppressor PTEN function, amplification or mutation of PI3K, amplification or mutation of Akt, activation of growth factor receptors, and exposure to carcinogens. Once activated, signaling through Akt can be propagated to a diverse array of substrates, including mTOR, a key regulator of protein translation. This pathway is an attractive therapeutic target in cancer because it serves as a convergence point for many growth stimuli, and through its downstream substrates, controls cellular processes that contribute to the initiation and maintenance of cancer. Moreover, activation of the Akt/mTOR pathway confers resistance to many types of cancer therapy, and is a poor prognostic factor for many types of cancers. This review will provide an update on the clinical progress of various agents that target the pathway, such as the Akt inhibitors perifosine and PX-866 and mTOR inhibitors (rapamycin, CCI-779, RAD-001) and discuss strategies to combine these pathway inhibitors with conventional chemotherapy, radiotherapy, as well as newer targeted agents. We will also discuss how the complex regulation of the PI3K/Akt/mTOR pathway poses practical issues concerning the design of clinical trials, potential toxicities and criteria for patient selection.
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Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ensaios Clínicos como Assunto , Terapia Combinada , Humanos , Neoplasias/enzimologia , Transdução de Sinais/efeitos dos fármacos , Especificidade por Substrato , Serina-Treonina Quinases TOR , Resultado do TratamentoRESUMO
PURPOSE OF REVIEW: Although designed to target only the HIV protease, HIV protease inhibitors induce toxicities in patients such as insulin resistance and lipodystrophy that suggest that protease inhibitors have other targets in mammalian cells. Akt controls insulin signaling and is an important target in cancer, but no Akt inhibitors are approved as cancer therapeutics. These observations have prompted the study of HIV protease inhibitors as inhibitors of Akt and possible cancer therapeutics. This review will highlight the latest advances in repositioning HIV protease inhibitors as cancer therapeutics. RECENT FINDINGS: Although protease inhibitors can inhibit Akt activation and the proliferation of over 60 cancer cell lines, as well as improve sensitivity to radiation or chemotherapy, these effects do not always correlate with Akt inhibition. Other important processes, such as the induction of endoplasmic reticulum stress, appear critical to the biological activity of protease inhibitors. These impressive and surprising preclinical data have prompted clinical testing of nelfinavir as a lead HIV protease inhibitor in cancer patients. SUMMARY: Although mechanisms of action for the antitumor effects of HIV protease inhibitors are complex, their broad spectrum of activity, minimal toxicity, and wide availability make protease inhibitors ideal candidates for repositioning as cancer therapeutics.
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Since the beginning of the acquired immunodeficiency syndrome (AIDS) epidemic, malignancies have been an important feature of this disease. Several cancers, including Kaposi sarcoma (KS), certain aggressive B-cell lymphomas, and cervical cancer, are considered AIDS-defining when they occur in patients infected with human immunodeficiency virus. Most AIDS-defining tumors are associated with one of 3 DNA viruses: KS-associated herpesvirus, Epstein-Barr virus, or human papillomavirus. With the introduction of highly active antiretroviral therapy (HAART), the incidence of KS and certain lymphomas has decreased, whereas that of other tumors, such as cervical cancer, has undergone little change. Several new drugs and therapies have been developed for KS and AIDS-related lymphomas, and these treatments, plus the development of HAART, have contributed to improvements in morbidity and mortality. At the same time, the improved overall survival of patients with HAART has contributed to an increase in the number of patients living with AIDS in developed countries such as the United States. With the development of HAART and improved prevention and treatment of opportunistic infections, an increasing percentage of the deaths in AIDS patients have been from malignancies. Strategies for prevention, screening, and therapy remain important areas of research in this developing field.
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Síndrome da Imunodeficiência Adquirida , Terapia Antirretroviral de Alta Atividade , Linfoma Relacionado a AIDS , Sarcoma de Kaposi , Infecções Oportunistas Relacionadas com a AIDS/etiologia , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Infecções Oportunistas Relacionadas com a AIDS/virologia , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/mortalidade , Síndrome da Imunodeficiência Adquirida/virologia , Humanos , Linfoma Relacionado a AIDS/tratamento farmacológico , Linfoma Relacionado a AIDS/etiologia , Linfoma Relacionado a AIDS/mortalidade , Linfoma Relacionado a AIDS/virologia , Sarcoma de Kaposi/tratamento farmacológico , Sarcoma de Kaposi/etiologia , Sarcoma de Kaposi/mortalidade , Sarcoma de Kaposi/virologiaRESUMO
BACKGROUND: An assessment of biomarkers from an analysis of human peripheral blood mononuclear cell gene-expression profiles was made, to acquire an understanding of transcriptional changes associated with human immunodeficiency virus type 1 (HIV-1) infection in vivo. METHODS: Supervised learning algorithms were used to create signature gene sets that could be used to distinguish seropositive from seronegative samples and delineate changes in disease status during the early stages of infection. Bioinformatic tools were used to classify persons and to functionally characterize groups of differentially expressed genes, to elucidate the impact of viral infection on host cell gene-expression patterns. RESULTS: A 10-gene signature set that could be used to accurately determine the HIV-1 serostatus was identified. A 6-gene signature set was used to distinguish seropositive persons exhibiting differential changes in CD4(+) T cell counts, with 93% accuracy. Functional classification of differentially expressed genes in HIV-1 indicated a preponderance of down-regulated genes with functions related to the immune response and apoptosis. Hierarchical cluster analysis in persons whose CD4(+) T cell counts increased, compared with that in persons whose CD4(+) T cell counts decreased, was characterized by the down-regulation of genes associated with apoptosis, mitochondrial function, protein biosynthesis, and RNA binding. CONCLUSIONS: Gene-expression profile analysis of a complex infectious virus, such as HIV-1, may be useful to elucidate the functional genomic relationships associated with viral infection.
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Perfilação da Expressão Gênica , Regulação da Expressão Gênica/fisiologia , Infecções por HIV/genética , Leucócitos Mononucleares/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Predisposição Genética para Doença , HumanosRESUMO
T-cell depletion facilitates reduced immunosuppression following organ transplantation and has been suggested to be pro-tolerant. However, the characteristics of post-depletional T cells have not been evaluated as they relate to tolerance induction. We therefore studied patients undergoing profound T-cell depletion with alemtuzumab or rabbit anti-thymocyte globulin following renal transplantation, evaluating the phenotype and functional characteristics of their residual cells. Naive T cells and T cells with potential regulatory function (CD4+CD25+) were not prevalent following aggressive depletion. Rather, post-depletion T cells were of a single phenotype (CD3+CD4+CD45RA-CD62L-CCR7-) consistent with depletion-resistant effector memory T cells that expanded in the first month and were uniquely prevalent at the time of rejection. These cells were resistant to steroids, deoxyspergualin or sirolimus in vitro, but were calcineurin-inhibitor sensitive. These data demonstrate that therapeutic depletion begets a limited population of functional memory-like T cells that are easily suppressed with certain immunosuppressants, but cannot be considered uniquely pro-tolerant.
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Memória Imunológica/efeitos dos fármacos , Imunossupressores/farmacologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Alemtuzumab , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Anticorpos Antineoplásicos/imunologia , Anticorpos Antineoplásicos/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Inibidores de Calcineurina , Humanos , Memória Imunológica/imunologia , Transplante de Rim/imunologia , Subpopulações de Linfócitos T/imunologiaRESUMO
We have previously shown that adoptive transfer of in vitro CD3/CD28 activated autologous CD4(+) T cells results in increased CD4 counts and CD4/CD8 ratios in HIV+ subjects. In this report, analysis of variable beta (Vbeta) chain T cell receptor (TCR) repertoire showed that CD3/CD28 stimulation was able to increase polyclonality within skewed spectra types in vitro. In vivo, two of eight subjects showed increase in TCR diversity and importantly, in no subject did a highly skewed in vivo repertoire emerge. Measurement of proliferative response to alloantigen showed increases following infusions. Response to pharmacological stimulus and lectin via Interferon-gamma ELISpot assay showed increases in a subset of subjects following infusions. However, interferon-gamma response to HIV antigens and peptides declined concurrent with stable or diminishing latent infectious viral load in CD4(+) T cells. These data provide further evidence that adoptive transfer of activated autologous CD4(+) T cells can augment the immune system.
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Antígenos CD28/imunologia , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/terapia , Imunoterapia Adotiva , Adulto , Feminino , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T/imunologia , Infecções por HIV/imunologia , Humanos , Interferon gama/metabolismo , Teste de Cultura Mista de Linfócitos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Linezolid has been associated with anemia and thrombocytopenia. Mechanisms for neither have been elucidated. OBJECTIVE: To propose mechanisms for linezolid-induced anemia and thrombocytopenia. CASE SUMMARY: A 78-year-old white woman with Staphylococcus epidermidis endocarditis was treated with linezolid after developing resistance to multiple antibiotic regimens. After 7 days of linezolid therapy, she developed thrombocytopenia, while an anemia present since admission remained unchanged. A bone marrow biopsy was performed, primarily looking for a mechanism for the thrombocytopenia. Histopathology revealed adequate megakaryocytes, ringed sideroblasts, and vacuolated pronormoblasts. A course of immune globulin (IVIG) was administered, with slowing in the rate of decline in platelets. She died 24 hours after her last dose of IVIG of congestive heart failure. DISCUSSION: The presence of ringed sideroblasts and vacuolated pronormoblasts suggests that linezolid-induced anemia is secondary to a chloramphenicol-like suppression of erythropoiesis. The presence of adequate, normal-appearing megakaryocytes suggests immune-mediated thrombocytopenia, not marrow suppression. Although the response to IVIG is difficult to interpret because of the patient's death, there was a slowing in the rate of decline of the platelet count, further supporting immune-mediated thrombocytopenia. An objective causality assessment indicated that the adverse drug event was probably due to linezolid. CONCLUSIONS: There appear to be 2 distinct mechanisms for linezolid-induced cytopenias. While anemia is reversible and manageable with transfusions, thrombocytopenia can be a treatment-limiting toxicity. The ability to treat through an immune-mediated cytopenia with IVIG may be beneficial for critically ill patients with few therapeutic options.
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Acetamidas/efeitos adversos , Anemia/induzido quimicamente , Oxazolidinonas/efeitos adversos , Trombocitopenia/induzido quimicamente , Acetamidas/farmacologia , Acetamidas/uso terapêutico , Idoso , Hipersensibilidade a Drogas/tratamento farmacológico , Endocardite Bacteriana/tratamento farmacológico , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Linezolida , Oxazolidinonas/farmacologia , Oxazolidinonas/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus epidermidis , Fatores de TempoRESUMO
Preclinical data are reported that support a human immunodeficiency virus (HIV) vaccine strategy using recombinant canarypox-HIV vectors (ALVAC-HIV) to load human dendritic cells (DCs) with HIV antigens. Clinical-grade DCs were infected with good manufacturing practice-grade ALVAC-HIV vaccine constructs. ALVAC infection, HIV gene expression, and DC viability and function were monitored by use of immunohistochemistry, flow cytometry, blastogenesis assays, antigen-specific interferon (IFN)-gamma enzyme-linked immunospot assay, and enzyme-linked immunosorbent assay protein detection. The vaccines infected both immature and mature DCs, and intracellular HIV-1 Gag protein was detected within hours. ALVAC-HIV induced DC maturation that was mediated by tumor necrosis factor-alpha and induced DC apoptosis that was directly related to the length of vaccine exposure. Of importance, the infected DCs remained functional in T cell stimulation assays and induced HIV antigen-specific CD8(+) T cell production of IFN-gamma from cells of HIV-1-infected individuals. These data support an ongoing HIV vaccine trial comparing conventional vaccine delivery routes with ex vivo vaccine-loaded autologous DCs for immunogenicity in HIV-1-uninfected volunteers.
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Vacinas contra a AIDS/imunologia , Vírus da Varíola dos Canários/imunologia , Células Dendríticas/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Vacinas Sintéticas/imunologia , Antígenos CD/análise , Separação Celular/métodos , Produtos do Gene gag/imunologia , Humanos , Imunofenotipagem , Vacinas Virais/síntese química , Vacinas Virais/imunologiaRESUMO
To study the safety and feasibility of T-cell reconstitution in HIV-infected individuals, we adoptively transferred activated autologous CD4+ T cells. Polyclonal peripheral blood CD4+ cells were costimulated ex vivo and subjects were given infusions of up to 3 x 1010 activated CD4+ cells. Dose-dependent increases in CD4+ cell counts and in the CD4:CD8 ratio were observed. Sustained increases in the fraction of cytokine-secreting T cells and decreases in the percentage of CD4+CCR5+ cells were noted in vivo, suggesting enhanced function and resistance to HIV infection. The frequency of CD4+Ki-67+ cells increased whereas CD4+ T cells containing T cell-receptor rearrangement excision circles (TRECs) decreased. These findings indicate that expansion of the peripheral T-cell pool mediated the increase in CD4 counts and suggest that approaches to reconstitute CD4 helper cell activity and decrease CCR5 expression may augment natural immunity to HIV infection.