Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Br J Dermatol ; 180(6): 1352-1360, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30207587

RESUMO

BACKGROUND: The relevance of granulocyte-macrophage colony-stimulating factor (GM-CSF) in the management of psoriasis has not been studied previously. GM-CSF is important in the initiation and maintenance of chronic inflammatory processes. OBJECTIVES: To investigate the clinical use of GM-CSF neutralization by evaluating the efficacy and safety of namilumab (AMG203), a monoclonal antibody GM-CSF inhibitor, in patients with moderate-to-severe plaque psoriasis. METHODS: A phase II, multicentre, randomized, double-blind, placebo-controlled, parallel-group, dose-finding, proof-of-concept study (NEPTUNE) was conducted. Four doses of namilumab (20, 50, 80 and 150 mg, via subcutaneous injection) were compared with placebo. Assessment of the primary end point - the proportion of patients achieving ≥ 75% reduction in Psoriasis Area and Severity Index (PASI 75 treatment response) - was performed at week 12. Exploratory investigation at the tissue level was conducted in a subset of the overall study population. The trial was registered with the number NCT02129777. RESULTS: In total, 122 patients were enrolled and 106 (86·9%) completed the double-blind treatment; 16 (13·1%) prematurely discontinued study medication. Serum concentration-time profiles were as expected for subcutaneous delivery of an IgG1 monoclonal antibody, and exposure increased proportionally with dose elevation. The number of patients showing PASI 75 treatment response at week 12 was low in all groups; no significant difference was recorded in this end point between placebo and any namilumab group. Similar outcomes were recorded for other clinical study end points. Moreover, no significant treatment-related changes from baseline were observed in laboratory investigations of cell types or subpopulations, or cytokines relevant to inflammatory pathways in psoriasis. CONCLUSIONS: GM-CSF blockade is not critical for suppression of key inflammatory pathways underlying psoriasis.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Fármacos Dermatológicos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Psoríase/tratamento farmacológico , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Fármacos Dermatológicos/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Masculino , Resultado do Tratamento
2.
Arthritis Res Ther ; 19(1): 53, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28274253

RESUMO

BACKGROUND: Namilumab (AMG203) is an immunoglobulin G1 monoclonal antibody that binds with high affinity to the GM-CSF ligand. This was a phase 1b, randomized, double-blind study (PRIORA) to assess namilumab in active, mild-to-moderate rheumatoid arthritis (RA). The primary outcome was the safety and tolerability of repeated subcutaneous injections of namilumab in patients with mild-to-moderate RA. METHODS: Adults with mild-to-moderate RA on stable methotrexate doses for ≥12 weeks were eligible. Patients received three subcutaneous injections of namilumab 150 or 300 mg, or placebo on days 1, 15, and 29, with 12 weeks' follow-up. Primary objective was safety/tolerability. RESULTS: Patients in cohort 1 were randomized to namilumab 150 mg (n = 8) or placebo (n = 5). In cohort 2, patients were randomized to namilumab 300 mg (n = 7) or placebo (n = 4). Incidence of treatment-emergent adverse events (TEAEs) was similar across the three groups (namilumab 150 mg: 63%; namilumab 300 mg: 57%; placebo: 56%). TEAEs in ≥10% of patients were nasopharyngitis (17%) and exacerbation/worsening of RA (13%). No anti-namilumab antibodies were detected. The pharmacokinetics of namilumab were linear and typical of a monoclonal antibody with subcutaneous administration. In a post hoc efficacy, per protocol analysis (n = 21), patients randomized to namilumab showed greater improvement in Disease Activity Score 28 (erythrocyte sedimentation rate and C-reactive protein [CRP]), swelling joint counts and tender joint counts compared with placebo. Difference in mean DAS28-CRP changes from baseline between namilumab and placebo favored namilumab at both doses and at all time points. In addition area under the curve for DAS28-CRP was analyzed as time-adjusted mean change from baseline. A significant improvement in DAS28-CRP was shown with namilumab (150 and 300 mg groups combined) compared with placebo at day 43 (p = 0.0117) and also 8 weeks after last dosing at day 99 (p = 0.0154). CONCLUSIONS: Subcutaneous namilumab was generally well tolerated. Although namilumab demonstrated preliminary evidence of efficacy, patient numbers were small; phase 2 studies are ongoing. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01317797 . Registered 18 February 2011.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antirreumáticos/administração & dosagem , Artrite Reumatoide/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antirreumáticos/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Clin Pharmacol Ther ; 89(6): 821-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21451504

RESUMO

Hepatitis C virus (HCV) infection is an issue of global concern, and studies are ongoing to identify new therapies that are both effective and safe. PF-4878691 is a Toll-like receptor 7 (TLR7) agonist modeled so as to dissociate its antiviral activities from its inflammatory activities. In a proof-of-mechanism study in healthy volunteers who received doses of 3, 6, and 9 mg of PF-4878691 twice a week for 2 weeks, PF-4878691 induced biomarkers of the immune and interferon (IFN) responses in a dose-dependent and dose-frequency-related manner. A novel finding was induction of TLR7 expression in vivo in response to PF-4878691, leading to an amplified biomarker response. A nonresponder at the 9-mg dose had a polymorphism in the IFN-α receptor 1 subunit (Val168Leu). Two subjects who had received 9-mg doses experienced serious adverse events (SAEs), characterized by flu-like symptoms, hypotension, and lymphopenia, leading to early termination of the study. TLR7 stimulation results in a pharmacologic response at levels commensurate with predicted antiviral efficacy, but these doses are associated with SAEs, raising concerns about the therapeutic window of this class of compounds for the treatment of HCV infection.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/imunologia , Imunidade Inata/efeitos dos fármacos , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/imunologia , Adulto , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptor 7 Toll-Like/biossíntese , Resultado do Tratamento , Adulto Jovem
5.
Br J Cancer ; 86(3): 336-41, 2002 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11875694

RESUMO

The objectives of this study were to determine the toxicity of intratumoural/intrapleural SRL172 in addition to intradermal SRL172 and standard chemotherapy (mitomycin-C, vinblastine and cisplatin) in patients with malignant mesothelioma. Patients received chemotherapy (mitomycin-C: 8 mg m(-2), vinblastine: 6 mg m(-2), cisplatin 50 mg m(-2)) on a 3-weekly basis for up to six courses. IP SRL172 injections were given 3-weekly prior to chemotherapy and escalated in groups of three patients from 1 microg to 1 mg bacilli in 10-fold increments. Patients were also given ID SRL172 at a dose of 1 mg bacilli 4-weekly. Patients were assessed for toxicity after each course of chemotherapy and for response by CT imaging. Immuno-haematological parameters were analyzed pre-treatment and 1 month after completion of treatment. There was no dose limiting toxicity with IP SRL172 although there was greater toxicity at the highest dose (n=13). There were six out of 16 partial responses (37.5%). Haemato-immunological parameters, measured in seven patients pre and post-therapy, revealed that response rate correlated with a decrease in platelet count and there was an increase in activation of natural killer cells and a decrease in the percentage of IL-4 producing T cells in all tested patients post-treatment. SRL172 can be given safely into tumour deposits and the pleural cavity in patients with malignant mesothelioma and we have established the dose for phase II testing.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Bacterianas/uso terapêutico , Mesotelioma/tratamento farmacológico , Idoso , Vacinas Bacterianas/efeitos adversos , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Mesotelioma/imunologia , Mesotelioma/mortalidade , Mesotelioma/patologia , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mycobacterium , Estadiamento de Neoplasias , Taxa de Sobrevida , Vimblastina/administração & dosagem
6.
Clin Oncol (R Coll Radiol) ; 14(1): 23-7, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11899903

RESUMO

BACKGROUND: SRL172 is a suspension of heat killed Mycobacterium vaccae, that has been found to be a potent immunological adjuvant when used with autologous cells in animal models. This is a phase II study to test the clinical activity, feasibility and safety of combining SRL172 with chemotherapy to treat patients with small cell lung cancer (SCLC). METHODS: Patients were randomized to receive chemotherapy with (n=14) or without (n=14) SRL172. The chemotherapy was either platinum-based (MVP, n=10) or anthracycline-based (ACE, n=18). SRL172 was given intradermally on day 0, weeks 4, 8 and then 3-6 monthly. RESULTS: The treatment arms were well balanced for disease extent (43% with limited stage in each arm). The toxicity of chemotherapy and overall response at 12-15 weeks (57%) was the same for both treatment regimens. Median survival was 8.6 months and 12.9 for patients treated with chemotherapy alone and with the combination respectively (P=0.10). The survival trend was similar for both disease extent and chemotherapy regimen employed in favour of combination chemotherapy with SRL172. CONCLUSIONS: There is a trend to improved median survival in SCLC with the combination of chemotherapy and SRL172 with no increased toxicity and irrespective of drug regimen. A phase III study examining chemotherapy in combination with SRL172 in SCLC is now underway.


Assuntos
Vacinas Bacterianas/uso terapêutico , Carcinoma de Células Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Mycobacterium , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
7.
Gene Ther ; 8(1): 1-4, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11402295

RESUMO

Protein transduction, an emerging technology with potential applications in gene therapy, can best be described as the internalisation of proteins into the cell, from the external environment. This process relies on the inherent property of a small number of proteins and peptides of being able to penetrate the cell membrane. The transducing property of these molecules can be conferred upon proteins which are expressed as fusions with them and thus offers an alternative to gene therapy for the delivery of therapeutic proteins into target cells. This review describes the three most commonly used protein transduction vehicles; the antennapedia peptide, the herpes simplex virus VP22 protein and HIV TAT protein transduction domain. The future prospects for the application of this technology in gene therapy are also discussed.


Assuntos
Terapia Genética/métodos , Proteínas Nucleares , Proteínas/genética , Transdução Genética , Proteína do Homeodomínio de Antennapedia , Produtos do Gene tat/genética , Proteínas de Homeodomínio/genética , Humanos , Fatores de Transcrição/genética , Proteínas Estruturais Virais/genética
8.
Eur J Heart Fail ; 3(2): 155-63, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11246052

RESUMO

BACKGROUND: It has not been assessed whether high levels of soluble interleukin 2 receptor (sIL-2R), neopterin and beta-2 microglobulin in idiopathic dilated cardiomyopathy reflect heart failure severity and/or an active autoimmune process. The aim of this study was to relate serum levels of these markers to clinical and autoimmune features. METHODS: We studied 60 patients with idiopathic dilated cardiomyopathy, 67 controls with ischemic heart failure and 34 normals. RESULTS: Abnormal levels of sIL-2R, but not of neopterin and beta-2 microglobulin, were more frequent in idiopathic dilated cardiomyopathy than in ischemic patients (35% vs. 16%; P=0.02) or in normals (35% vs. 12%, P=0.01); mean sIL-2R levels were, however, similar in idiopathic dilated cardiomyopathy and ischemic heart failure (842+/-75 vs. 762+/-93 U/ml, P=NS). In idiopathic dilated cardiomyopathy abnormal levels of sIL-2R were associated with lower peak oxygen consumption (P=0.008), higher neopterin and HLA class II expression in the myocardium (P=0.02), but were unrelated to cardiac autoantibody status or titer. In addition, abnormal levels of neopterin were associated with adverse prognosis and higher beta-2 microglobulin; abnormal levels of beta-2 microglobulin with lower echocardiographic percent fractional shortening, higher sIL-2R and higher neopterin. CONCLUSIONS: There is no convincing evidence that abnormal sIL-2R, neopterin and/or beta-2 microglobulin are disease-specific markers of idiopathic dilated cardiomyopathy. The lack of association with cardiac autoantibodies suggests that these abnormalities are mainly related to heart failure severity rather than autoimmune pathogenesis. In keeping with this view, high levels of sIL-2R, neopterin and/or beta-2 microglobulin identified a subset of idiopathic dilated cardiomyopathy patients with advanced disease and poor prognosis.


Assuntos
Doenças Autoimunes/diagnóstico , Cardiomiopatia Dilatada/diagnóstico , Neopterina/sangue , Receptores de Interleucina-2/sangue , Microglobulina beta-2/sangue , Adolescente , Adulto , Idoso , Autoanticorpos/sangue , Doenças Autoimunes/imunologia , Cardiomiopatia Dilatada/imunologia , Criança , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
9.
J Immunol Methods ; 247(1-2): 1-8, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11150531

RESUMO

When lymphocytes from genetically different individuals are mixed together in tissue culture blast transformation occurs, a reaction known as the mixed lymphocyte reaction (MLR). The MLR is a clinically relevant in vitro assay where lymphocytes from one individual (effector, E) are incubated with the lymphocytes of another individual (stimulator, S) which have been previously rendered incapable of blast transformation by gamma-irradiation. We have standardised a whole blood (WB) MLR assay where the E lymphocytes were provided by 20 microl of WB and the S lymphocytes were provided by irradiated peripheral blood mononuclear cells (PBMCs) either as a mixed pool of 20 donor PBMCs or as single donor PBMC. The optimum number of S lymphocytes needed was comparatively higher than in the standard PBMC MLR: the optimum calculated E:S ratio was 1:20 compared to a E:S ratio of 1:1 or 3:2 in the standard PBMC MLR. In ten normal individuals the WB/PBMC MLR was similar to the standard PBMC/PBMC MLR. As a clinical example, the WB/PBMC MLR proliferative capacity of 13 patients with malignant mesothelioma was no different from the proliferative capacity of their age-sex matched controls. This standardised WB/PBMC MLR assay is a simple and more practical assay than the standard MLR assay and can be incorporated easily in clinical studies with biological end-points.


Assuntos
Teste de Cultura Mista de Linfócitos/normas , Linfócitos/imunologia , Idoso , Feminino , Humanos , Leucócitos Mononucleares/citologia , Contagem de Linfócitos , Teste de Cultura Mista de Linfócitos/métodos , Masculino , Mesotelioma/sangue , Mesotelioma/imunologia , Pessoa de Meia-Idade
10.
BJU Int ; 86(6): 742-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11069388

RESUMO

OBJECTIVE: To investigate cancer immunotherapy using whole allogeneic (differing tissue-type) tumour cells as vaccines in the rat prostate cancer model. Materials and methods Two rat models of prostate cancer were used; MAT-LyLu tumours which grow in Copenhagen rats and PAIII tumours which grow in Lobund-Wistar rats, with crossover of the cell lines to test allogeneic vaccination. The cell lines were immunologically characterized by flow cytometry. Irradiated tumour cells were administered as subcutaneous vaccines either before tumour challenge or after tumour establishment (both subcutaneous). A preparation of heat-killed Mycobacterium vaccae bacilli (SRL172) was used as an adjuvant to increase vaccine efficiency. RESULTS: Flow cytometry analysis of the cell lines showed that the PAIII cells had higher levels of major histocompatibility complex (MHC) class I and intercellular adhesion molecule (ICAM-1) expression than the MAT-LyLu cells. However, both tumour cell lines were rejected in their allogeneic hosts. Prophylactic vaccination with allogeneic MAT-LyLu cells protected against PAIII tumour challenge in Lobund-Wistar rats, with 80% of animals surviving for > 5 months, compared with 40% for animals receiving autologous cells. The immunity was prolonged, as rats were protected when rechallenged 5 months later. In Copenhagen rats allogeneic PAIII cells protected against the more aggressive MAT-LyLu tumour challenge only when the cells were combined with SRL172. Initial therapy experiments showed that vaccination with the cell lines mediated only limited tumour regression in the Lobund-Wistar rats. CONCLUSION: The allogeneic tumour cell vaccination model described is valuable for assessing the principle and efficacy of allogeneic prostate cancer cell vaccines for clinical use.


Assuntos
Vacinas Anticâncer/uso terapêutico , Neoplasias da Próstata/terapia , Animais , Modelos Animais de Doenças , Citometria de Fluxo , Imunoterapia/métodos , Molécula 1 de Adesão Intercelular/metabolismo , Complexo Principal de Histocompatibilidade/fisiologia , Masculino , Mycobacterium/imunologia , Ratos , Células Tumorais Cultivadas
11.
Br J Cancer ; 83(7): 853-7, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10970684

RESUMO

Mycobacterial preparations have been used with limited success against cancer apart from superficial bladder cancer. Recently, a therapeutic vaccine derived from Mycobacterium vaccae has been given to patients with prostate cancer and melanoma indicating a possible beneficial effect on disease activity in such patients. We have recently initiated a series of randomized studies to test the feasibility and toxicity of combining a preparation of heat-killed Mycobacterium vaccae (designated SRL172) with a multidrug chemotherapy regimen to treat patients with inoperable non-small cell lung cancer (NSCLC) and mesothelioma. 28 evaluable patients with previously untreated symptomatic NSCLC and mesothelioma were randomized to receive either 3 weekly intravenous combination chemotherapy alone, or chemotherapy given with monthly intra-dermal injections of SRL172. Safety and tolerability were scored by common toxicity criteria and efficacy was evaluated by survival of patients and by tumour response assessed by CT scanning. The toxicity of chemotherapy was similar in the two groups. SRL172 caused mild inflammation at the injection site. In the group of patients randomized to receive chemotherapy combined with SRL172, there was a trend towards improved response rate (54% vs. 33%) with more patients in the combined arm receiving radical surgery and radiotherapy, improved median survival (9.7 months vs. 7.5 months) and improved 1 year survival (42% vs. 18%). SRL172 appeared to improve sleep (P = 0.08) and improved appetite (P = 0.01). There was no detectable change in serum cytokine levels for gamma-interferon and TNF-alpha before and after treatment. In patients with NSCLC and mesothelioma, there may be a beneficial interaction when chemotherapy is administered in combination with SRL172. Confirmation of this effect and further investigation is underway in a randomized phase III trial and in laboratory models.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Bacterianas/uso terapêutico , Vacinas Anticâncer/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Mesotelioma/terapia , Mycobacterium/imunologia , Adjuvantes Imunológicos/efeitos adversos , Adjuvantes Imunológicos/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Vacinas Bacterianas/efeitos adversos , Vacinas Bacterianas/imunologia , Vacinas Anticâncer/efeitos adversos , Vacinas Anticâncer/imunologia , Carcinoma Pulmonar de Células não Pequenas/imunologia , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Feminino , Humanos , Imunoterapia Ativa , Interferon gama/sangue , Interleucina-10/sangue , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Masculino , Mesotelioma/tratamento farmacológico , Mesotelioma/imunologia , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitomicina/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/uso terapêutico , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos
12.
Viral Immunol ; 13(1): 9-17, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10733164

RESUMO

HIV induces disease only following chronic activation of the immune system. Other retroviruses such as the mouse mammary tumour virus (MMTV) activate a large percentage of T cells by encoding a superantigen (SAg). To date there is no evidence that HIV encodes a SAg. An alternative way to induce pan-activation of the immune system is by allogeneic stimulation, which occurs following transplantation. Here we extend previous work which demonstrated that HIVpg120 could bind peptides in a similar manner to HLA, by demonstrating that human antigen presenting cells (APCs) expressing gp120 (but not DR1) can present a DR1-restricted peptide to induce proliferation of a DR1-restricted peptide-specific T-cell line in a similar manner to the same peptide presented by a DR1 expressing APC. Our data provide strong support for the hypothesis that the HLA-like regions of gp120 encode functional properties shared with HLA, and could explain the extraordinary clinical and immunological similarities between AIDS and chronic graft versus host disease.


Assuntos
Proteína gp120 do Envelope de HIV/imunologia , Antígenos HLA/imunologia , Peptídeos/imunologia , Linfócitos T/imunologia , Animais , Apresentação de Antígeno , Células Apresentadoras de Antígenos/imunologia , Linhagem Celular , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/metabolismo , Antígenos HLA/metabolismo , Antígeno HLA-DR1/imunologia , Antígeno HLA-DR1/metabolismo , Humanos , Ativação Linfocitária , Camundongos , Fragmentos de Peptídeos/imunologia , Peptídeos/metabolismo
13.
Cytometry ; 39(1): 72-8, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10655565

RESUMO

BACKGROUND: Natural killer (NK) cells produce multiple cytokines with potential immune regulatory roles. We standardised a whole-blood flow cytometry method to visualise intracellular cytokine production by NK cells for the study of NK cell biology and for clinical monitoring. METHODS: With a three-colour fluorescent labelling technique, specific cytokine production by NK or T cells was visualised directly in whole blood in the same sample after stimulation by phorbol 12-myristate 13-acetate (PMA) and ionomycin and by electronically gating on the CD3-ve/CD56+ve NK population or on the CD3+/CD56+ NK-T-cell population. RESULTS: Detectable levels of tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) but not of interleukin-2 (IL-2) or IL-4 were easily observed in NK cells. The visualisation of the cytokine production by NK cells was dependent on the addition of a Golgi transport inhibitor, Brefeldin A. Other known stimuli for NK cells (IL-2 and CD16 monoclonal antibody and incubation with K562, the NK-sensitive cell line) promoted IFN-gamma and TNF-alpha production in NK cells to a lesser extent than did PMA and ionomycin stimulation. CONCLUSIONS: This whole-blood flow cytometric assay appears to be an useful and easy method to examine cytokine production by NK cells and/or by CD3+CD56+ NK-T lymphocytes in patients with relevant diseases.


Assuntos
Citocinas/análise , Citometria de Fluxo/métodos , Células Matadoras Naturais/metabolismo , Linfócitos T/metabolismo , Brefeldina A/farmacologia , Complexo CD3/análise , Antígeno CD56/análise , Humanos , Células K562 , Células Matadoras Naturais/efeitos dos fármacos , Monensin/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Linfócitos T/efeitos dos fármacos
14.
Mech Ageing Dev ; 121(1-3): 113-21, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11164465

RESUMO

Protein transduction can be described as the direct uptake by the cell of exogenous proteins/peptides or protein/peptide:chemical complexes, as a result of a specific property of the protein/peptide component. In this review, the three most widely studied protein transducing activities are described, with particular emphasis on the TAT protein transduction domain. Current progress in protein transduction technology suggests the potential development of a variety of molecular and cell biology tools that will enable researchers to by-pass conventional genetic routes for modulating the cells' biological activity, thus negating many of the problems associated with genetic intervention. The potential application of this class of molecule in the development of tools for the study of senescent populations is discussed.


Assuntos
Proteínas/genética , Transdução Genética , Animais , Antígenos Transformantes de Poliomavirus/química , Antígenos Transformantes de Poliomavirus/farmacologia , Divisão Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Humanos , Fragmentos de Peptídeos/farmacologia , Transdução Genética/métodos
16.
Gene Ther ; 6(8): 1475-81, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10467372

RESUMO

Genetic modification of tumour cells with the GM-CSF encoding gene renders these cells more potent, as autologous tumour cell vaccine, than their wild-type counterparts. However, autologous vaccines are impractical for wide-scale clinical use and we have therefore investigated the efficacy of the GM-CSF genetic modification approach with an allogeneic whole cell tumour vaccine. In this report, we show that the allogeneic K1735-M2 (H-2k) melanoma cell vaccine induces a specific protective anti-tumour response against the syngeneic B16-F10 (H-2b) melanoma tumour in C57BL/6J mice. In vitro T cell work demonstrated that vaccination of animals with the allogeneic cell vaccine generated cytotoxic T cells specific for the autologous tumour. In vivo T cell subset depletion experiments also illustrated that this anti-tumour effect was mediated by both CD4+ve and CD8+ve T cells, suggesting that the allogeneic vaccine may operate through the 'cross-priming' phenomenon whereby tumour antigens are processed and presented to T cells by the host's own antigen presenting cells (APC). Thus, we transduced K1735-M2 cells with a GM-CSF expressing retroviral vector and showed anti-tumour activity of the GM-CSF secreting K1735-M2 cells as a therapeutic vaccine against the syngeneic B16-F10 tumour. Our data imply that GM-CSF genetically modified allogeneic whole cell tumour vaccines could be successful in the clinic. In addition, more potent combination gene therapy strategies could be tested using this therapeutic allogeneic vaccine model.


Assuntos
Vacinas Anticâncer/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Melanoma Experimental/terapia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/metabolismo , Vetores Genéticos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias , Análise de Sobrevida , Transdução Genética , Transplante Homólogo , Células Tumorais Cultivadas
17.
J Immunol ; 163(1): 62-70, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10384100

RESUMO

The ability of NK cells to kill tumor cells is controlled by a balance between activating and inhibitory signals transduced by distinct receptors. In murine tumor models, the costimulatory molecule B7.1 not only acts as a positive trigger for NK-mediated cytotoxicity but can also overcome negative signaling transduced by MHC class I molecules. In this study, we have evaluated the potential of human B7.1-CD28 interaction as an activating trigger for human blood NK cells. Using multiparameter flow cytometric analysis and a panel of different CD28 mAbs, we show that human peripheral blood NK cells (defined by CD56+, CD16+, and CD3- surface expression) express the CD28 costimulatory receptor, with its detection totally dependent on the mAb used. In addition, the level of CD28 varies among individuals and on different NK cell lines, irrespective of CD28 steady-state mRNA levels. By performing Ab binding studies on T cells, our data strongly suggest that binding of two of the anti-CD28 Abs (clones 9.3 and CD28.2) is to a different epitope to that recognized by clones L293 and YTH913.12, which is perhaps modified in the CD28 molecule expressed by the NK cells. We also show that B7.1 enhances the NK-mediated lysis of NK-sensitive but not of NK-resistant tumor cells and that this increased lysis is dependent on CD28-B7 interactions as shown by the ability of Abs to block this lysis. Coculture of the B7.1-positive NK-sensitive cells also led to the activation of the NK cells, as determined by the expression of CD69, CD25, and HLA class II.


Assuntos
Antígeno B7-1/fisiologia , Antígenos CD28/biossíntese , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos/metabolismo , Adulto , Animais , Anticorpos Monoclonais/metabolismo , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos T/biossíntese , Linfócitos B/imunologia , Sítios de Ligação de Anticorpos , Antígenos CD28/sangue , Antígenos CD28/genética , Separação Celular , Células Cultivadas , Células Clonais , Técnicas de Cocultura , Citotoxicidade Imunológica/imunologia , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/metabolismo , Antígenos HLA/biossíntese , Antígenos de Histocompatibilidade Classe II/biossíntese , Humanos , Células K562/imunologia , Células Matadoras Naturais/imunologia , Lectinas Tipo C , Subpopulações de Linfócitos/imunologia , Camundongos , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , Receptores de Interleucina-2/biossíntese , Sarcoma Experimental/imunologia , Especificidade da Espécie , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transcrição Gênica/imunologia , Células Tumorais Cultivadas
18.
Immunol Lett ; 66(1-3): 81-7, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10203038

RESUMO

The existence of HIV positive individuals who do not appear to progress to disease, or do so only very slowly (LTNPs), strongly suggest that factors other than virus pathogenicity determine disease. The occurence of HIV infected chimpanzees that remain disease free and other African SIV infected primates where disease is apparently species specific underscores the importance of host factors [1,2]. We have examined the immune response of LTNP patients using a variety of techniques including intracellular cytokine FACscan, anchor PCR analysis of the T cell receptor and HLA typing of class II genes by DNA sequencing. Our results to date confirm that the development of disease is consistent with activation of a susceptible immune system, and that this could be due to the fact that HLA-like sequences of HIV may 'allo' activate the host immune response. In order to test this hypothesis further we have examined whether gp120 itself can bind and present specific peptides which may be capable of eliciting 'allo' activation responses in particular hosts.


Assuntos
Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , Apresentação de Antígeno , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular , Simulação por Computador , Citocinas/análise , Progressão da Doença , Anticorpos Anti-HIV/imunologia , Antígeno HLA-DR1/imunologia , Teste de Histocompatibilidade , Humanos , Sistema Imunitário , Líquido Intracelular , Fragmentos de Peptídeos/imunologia , Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T/genética
19.
AIDS ; 13(18): 2515-21, 1999 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-10630520

RESUMO

OBJECTIVE: To screen HIV-positive, long-term exposed seronegative and low-risk individuals for the presence of antibodies against regions of HIV-1 gp120 that share some degree of homology with HLA. METHODS: Sera were obtained from 63 HIV-1-infected subjects [52 Centers for Disease Control and Prevention (CDC) stage 2 and 11 stages 3/4], 32 HIV-exposed uninfected (HEU) subjects and from 24 low-risk HIV-1 seronegative individuals. They were tested by a peptide-based enzyme-linked immunosorbent assay (ELISA) for reactivity against peptides derived from the HIV-1 gp120 C-terminal region that contain regions of MHC sequence/structural similarity. Ten randomly selected sera from each group were also screened for anti-class I antibodies. RESULTS: Thirty per cent of the long-term HIV-1-exposed seronegative individuals had antibodies against the conserved C-terminal region (C5) of HIV-1 gp120. However, sera from HEU individuals showed no reactivity against other peptides derived from the C2 region of gp120, also an HLA homologous region. Anti-C terminal gp120 antibodies were mainly of IgM subclass, although IgG-specific antibodies were also present. In addition, 70% of HEU individuals had antibodies to HLA class I molecules compared with 15% of HIV-positive patients (restricted to only those HIV-positive patients with anti C-terminal antibodies). CONCLUSION: Our results suggest that antibody responses against the C-terminal region of HIV gp120 and HLA class I may represent markers of apparent natural protection against HIV-1 infection.


Assuntos
Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Fragmentos de Peptídeos/imunologia , Sorodiagnóstico da AIDS , Ensaio de Imunoadsorção Enzimática , Epitopos , Feminino , Sobreviventes de Longo Prazo ao HIV , Soronegatividade para HIV , Antígenos HLA/imunologia , Humanos , Imunoglobulina M/sangue , Masculino
20.
J Immunol Methods ; 217(1-2): 177-84, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9776587

RESUMO

The assessment of natural killer cell activity at baseline and the monitoring of this activity during treatment is important in many diseases especially in patients with cancer and AIDS. An optimised and standardised whole blood chromium release assay is described using K562 cells, the standard target erythroleukaemic cell line. The tumour cell lysis observed using whole blood is comparable to that obtained with the standard 4 h lysis assay using peripheral blood mononuclear cells as effector cells. Results with the whole blood assay are reproducible when the incubation with K562 cells is performed over a period of 18 h. The assay necessitates only 0.6 ml of blood collected in 10 IU/ml of sodium heparin as the anticoagulant. In this report, depletion experiments, also standardised using whole blood, show that the effector cells in the whole blood assay are contained within the CD56 + cell population. This assay will be of interest where the immunological status of patients with different diseases need to be frequently monitored.


Assuntos
Testes Imunológicos de Citotoxicidade , Células Matadoras Naturais/imunologia , Anticoagulantes/farmacologia , Antígeno CD56/análise , Separação Celular , Ácido Cítrico/farmacologia , Ácido Edético/farmacologia , Citometria de Fluxo , Glucose/análogos & derivados , Glucose/farmacologia , Heparina/farmacologia , Humanos , Células K562 , Depleção Linfocítica , Subpopulações de Linfócitos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...