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1.
J Allergy Clin Immunol Pract ; 10(7): 1825-1834.e8, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35398554

RESUMO

BACKGROUND: Asthma can occur at any age but the differences in patient characteristics between childhood-, adult-, and late-onset asthma are not well understood. OBJECTIVE: To investigate differences in patients' characteristics by age at asthma onset. METHODS: From 5 European electronic databases, we created a cohort encompassing adult patients with doctor-diagnosed asthma in 2008 to 2013. Patients were categorized based on their age at asthma onset: childhood-onset (age at onset < 18 y), adult-onset (age at onset 18-40 y), and late-onset asthma (age at onset ≥ 40 y). Comorbidities were assessed at study entry. For each characteristic and comorbidity, odds ratios and age- and sex-adjusted odds ratios (ORadj) comparing asthma-onset categories were estimated per database and combined in a meta-analysis using a random effect model. RESULTS: In total, 586,436 adult asthma patients were included, 81,691 had childhood-onset, 218,184 adult-onset, and 286,561 late-onset asthma. Overall, 7.3% had severe asthma. Subjects with adult-onset compared with childhood-asthma had higher risks for overweight/obesity (ORadj 1.4; 95% CI 1.1-1.8) and lower risks for atopic disorders (ORadj 0.8; 95% CI 0.7-0.95). Patients with late-onset compared with adult-onset asthma had higher risks for nasal polyposis (ORadj 1.8; 95% CI 1.2-2.6), overweight/obesity (ORadj 1.3; 95% CI 1.2-1.4), gastroesophageal reflux disease (ORadj 1.4; 95% CI 1.2-1.7), and diabetes (ORadj 2.3; 95% CI 1.8-2.9). A significant association between late-onset asthma and uncontrolled asthma was observed (ORadj 2.8; 95% CI 1.7-4.5). CONCLUSIONS: This international study demonstrates clear differences in comorbidities between childhood-, adult-, and late-onset asthma phenotypes in adults. Furthermore, patients with late-onset asthma had more frequent uncontrolled asthma.


Assuntos
Asma , Sobrepeso , Idade de Início , Asma/epidemiologia , Criança , Estudos de Coortes , Humanos , Obesidade
2.
Health Technol Assess ; 25(66): 1-126, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34812138

RESUMO

BACKGROUND: Although routine NHS data potentially include all patients, confounding limits their use for causal inference. Methods to minimise confounding in observational studies of implantable devices are required to enable the evaluation of patients with severe systemic morbidity who are excluded from many randomised controlled trials. OBJECTIVES: Stage 1 - replicate the Total or Partial Knee Arthroplasty Trial (TOPKAT), a surgical randomised controlled trial comparing unicompartmental knee replacement with total knee replacement using propensity score and instrumental variable methods. Stage 2 - compare the risk benefits and cost-effectiveness of unicompartmental knee replacement with total knee replacement surgery in patients with severe systemic morbidity who would have been ineligible for TOPKAT using the validated methods from stage 1. DESIGN: This was a cohort study. SETTING: Data were obtained from the National Joint Registry database and linked to hospital inpatient (Hospital Episode Statistics) and patient-reported outcome data. PARTICIPANTS: Stage 1 - people undergoing unicompartmental knee replacement surgery or total knee replacement surgery who met the TOPKAT eligibility criteria. Stage 2 - participants with an American Society of Anesthesiologists grade of ≥ 3. INTERVENTION: The patients were exposed to either unicompartmental knee replacement surgery or total knee replacement surgery. MAIN OUTCOME MEASURES: The primary outcome measure was the postoperative Oxford Knee Score. The secondary outcome measures were 90-day postoperative complications (venous thromboembolism, myocardial infarction and prosthetic joint infection) and 5-year revision risk and mortality. The main outcome measures for the health economic analysis were health-related quality of life (EuroQol-5 Dimensions) and NHS hospital costs. RESULTS: In stage 1, propensity score stratification and inverse probability weighting replicated the results of TOPKAT. Propensity score adjustment, propensity score matching and instrumental variables did not. Stage 2 included 2256 unicompartmental knee replacement patients and 57,682 total knee replacement patients who had severe comorbidities, of whom 145 and 23,344 had linked Oxford Knee Scores, respectively. A statistically significant but clinically irrelevant difference favouring unicompartmental knee replacement was observed, with a mean postoperative Oxford Knee Score difference of < 2 points using propensity score stratification; no significant difference was observed using inverse probability weighting. Unicompartmental knee replacement more than halved the risk of venous thromboembolism [relative risk 0.33 (95% confidence interval 0.15 to 0.74) using propensity score stratification; relative risk 0.39 (95% confidence interval 0.16 to 0.96) using inverse probability weighting]. Unicompartmental knee replacement was not associated with myocardial infarction or prosthetic joint infection using either method. In the long term, unicompartmental knee replacement had double the revision risk of total knee replacement [hazard ratio 2.70 (95% confidence interval 2.15 to 3.38) using propensity score stratification; hazard ratio 2.60 (95% confidence interval 1.94 to 3.47) using inverse probability weighting], but half of the mortality [hazard ratio 0.52 (95% confidence interval 0.36 to 0.74) using propensity score stratification; insignificant effect using inverse probability weighting]. Unicompartmental knee replacement had lower costs and higher quality-adjusted life-year gains than total knee replacement for stage 2 participants. LIMITATIONS: Although some propensity score methods successfully replicated TOPKAT, unresolved confounding may have affected stage 2. Missing Oxford Knee Scores may have led to information bias. CONCLUSIONS: Propensity score stratification and inverse probability weighting successfully replicated TOPKAT, implying that some (but not all) propensity score methods can be used to evaluate surgical innovations and implantable medical devices using routine NHS data. Unicompartmental knee replacement was safer and more cost-effective than total knee replacement for patients with severe comorbidity and should be considered the first option for suitable patients. FUTURE WORK: Further research is required to understand the performance of propensity score methods for evaluating surgical innovations and implantable devices. TRIAL REGISTRATION: This trial is registered as EUPAS17435. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 66. See the NIHR Journals Library website for further project information.


We compared the risks and benefits of partial and total knee replacements in NHS patients with a complex medical history who would normally be excluded from randomised trials on this topic. We used information that was collected during hospital appointments for people who had a knee replacement between 2009 and 2016. It is difficult to directly compare the two groups because each individual patient has a different medical history. We tested advanced statistical methods to account for these differences. In stage 1, we showed that some of these advanced statistical methods could replicate the results of a recently published surgical trial using routine data from the NHS. We compared patients in the trial with similar patients who were operated on in the NHS. Three of the proposed methods showed results similar to those obtained from the Total or Partial Knee Arthroplasty Trial (TOPKAT). In stage 2, we used the successful methods from stage 1 to study the risks, benefits and costs of partial and total knee replacement surgery in patients with complex medical histories. Two of the statistical methods found that patients who had a partial knee replacement had less self-reported pain and better function after surgery than patients who had a total knee replacement. All three methods found that partial knee replacement was safer, was associated with a lower risk of blood clots (a known complication of knee surgery) and had lower mortality over 5 years. However, patients who had a partial knee replacement were twice as likely as those with a total knee replacement to need a second surgery within 5 years. We found that partial knee replacements were less costly to the NHS and were associated with better overall quality of life for patients than total knee replacement.


Assuntos
Artroplastia do Joelho , Estudos de Coortes , Análise Custo-Benefício , Humanos , Pontuação de Propensão , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida
3.
Respir Med ; 165: 105919, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32174450

RESUMO

BACKGROUND: Data on the risk of death following an asthma exacerbation are scarce. With this multinational cohort study, we assessed all-cause mortality rates, mortality rates following an exacerbation, and patient characteristics associated with all-cause mortality in asthma. METHODS: Asthma patients aged ≥18 years and with ≥1 year of follow-up were identified in 5 European electronic databases from the Netherlands, Italy, UK, Denmark and Spain during the study period January 1, 2008-December 31, 2013. Patients with asthma-COPD overlap were excluded. Severe asthma was defined as use of high dose ICS + use of a second controller. Severe asthma exacerbations were defined as emergency department visits, hospitalizations or systemic corticosteroid use, all for reason of asthma. RESULTS: The cohort consisted of 586,436 asthma patients of which 42,611 patients (7.3%) had severe asthma. The age and sex standardized all-cause mortality rates ranged between databases from 5.2 to 9.5/1000 person-years (PY) in asthma, and between 11.3 and 14.8/1000 PY in severe asthma. The all-cause mortality rate in the first week following a severe asthma exacerbation ranged between 14.1 and 59.9/1000 PY. Mortality rates remained high in the first month following a severe asthma exacerbation and decreased thereafter. Higher age, male gender, comorbidity, smoking, and previous severe asthma exacerbations were associated with mortality. CONCLUSION: All-cause mortality following a severe exacerbation is high, especially in the first month following the event. Smoking cessation, comorbidity-management and asthma-treatment focusing on the prevention of exacerbations might reduce associated mortality.


Assuntos
Asma/mortalidade , Corticosteroides , Fatores Etários , Causas de Morte , Estudos de Coortes , Comorbidade , Progressão da Doença , Uso de Medicamentos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Europa (Continente)/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Índice de Gravidade de Doença , Fatores Sexuais , Fumar/efeitos adversos
4.
BMJ Open ; 8(4): e017273, 2018 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-29627803

RESUMO

PURPOSE: The aim of this article is to provide a detailed description of the ongoing nationwide Danish Centre for Strategic Research in Type 2 Diabetes (DD2) project cohort and biobank. The DD2 cohort continuously enrols newly diagnosed patients with type 2 diabetes (T2D) throughout Denmark. The overall goal of the DD2 project is to establish a large and data-rich T2D cohort that can serve as a platform for exhaustive T2D research including (1) improved genotypic and phenotypic characterisation of T2D, (2) intervention studies of more individualised T2D treatment, (3) pharmacoepidemiological studies and (4) long-term follow-up studies on predictors of T2D complications and prognosis. PARTICIPANTS: Between 2010 and 2016, 7011 individuals with T2D have been enrolled and assessed at baseline. Information collected include interview data (eg, body weight at age 20 years, physical activity and alcohol consumption), clinical examination data (eg, hip-waist ratio and resting heart rate) and biological samples (whole blood, DNA, plasma and urine) stored at -80°C and currently analysed for a range of biomarkers and genotypes. FINDINGS TO DATE: Registry linkage has provided extensive supplemental continuous data on glycosylated haemoglobin A, lipids, albuminuria, blood pressure, smoking habits, body mass index, primary care contacts, hospital diagnoses and procedures, medication use, cancer and mortality. Cross-sectional associations between biomarkers, family history, anthropometric and lifestyle measures and presence of complications at baseline have been reported. FUTURE PLANS: During 2016, a detailed follow-up questionnaire has been answered by 85% of initial participants, providing follow-up information on baseline variables and on presence of diabetic neuropathy. The DD2 cohort has now been followed for a total of 18 862 person-years, and nested intervention trials and follow-up studies are ongoing. In the future, the cohort will serve as a strong national and international resource for recruiting patients to nested case studies, clinical trials, postmarketing surveillance, large-scale genome studies and follow-up studies of T2D complications.


Assuntos
Pesquisa Biomédica , Diabetes Mellitus Tipo 2 , Estudos de Coortes , Estudos Transversais , Dinamarca , Feminino , Hemoglobinas Glicadas , Humanos , Masculino
5.
J Diabetes Complications ; 32(1): 34-40, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29107454

RESUMO

AIMS: To examine the prevalence of micro- and macrovascular complications and their associated clinical characteristics at time of type 2 diabetes (T2D) diagnosis. METHODS: We examined the prevalence of complications and associated clinical characteristics among 6958 newly diagnosed T2D patients enrolled in the prospective Danish Center for Strategic Research in T2D cohort during 2010-2016. We calculated age- and gender-adjusted prevalence ratios (aPRs) of complications using log-binomial and Poisson regression. RESULTS: In total, 35% (n=2456) T2D patients had diabetic complications around diagnosis; 12% (n=828) had microvascular complications, 17% (n=1186) macrovascular complications, and 6% (n=442) had both. HbA1c levels of ≥7% were associated with microvascular complications [HbA1c 7%-8%; aPR: 1.35, 95% confidence interval (CI): 1.12-1.62] but not macrovascular complications [aPR: 0.91, 95% CI: 0.76-1.08]. High C-peptide≥800pmol/L was associated with macrovascular [aPR 1.34, 95% CI: 1.00-1.80] but not microvascular [aPR 0.97, 95% CI: 0.71-1.33] complications. Macrovascular complications were associated with male sex, age>50years, obesity, hypertriglyceridemia, low HDL cholesterol, smoking, elevated CRP levels, and anti-hypertensive therapy. Microvascular complications were associated with high blood pressure, hypertriglyceridemia, and absence of lipid-lowering therapy. CONCLUSIONS: One-third of patients with T2D had diabetes complications around time of diagnosis. Our findings suggest different pathophysiological mechanisms behind micro- and macrovascular complications.


Assuntos
Diagnóstico Tardio/estatística & dados numéricos , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos Transversais , Dinamarca/epidemiologia , Angiopatias Diabéticas/classificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Tempo
6.
J Transl Med ; 9: 33, 2011 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-21450101

RESUMO

BACKGROUND: Infiltration of colorectal carcinomas (CRC) with T-cells has been associated with good prognosis. There are some indications that chemokines could be involved in T-cell infiltration of tumors. Selective modulation of chemokine activity at the tumor site could attract immune cells resulting in tumor growth inhibition. In mouse tumor model systems, gene therapy with chemokines or administration of antibody (Ab)-chemokine fusion proteins have provided potent immune mediated tumor rejection which was mediated by infiltrating T cells at the tumor site. To develop such immunotherapeutic strategies for cancer patients, one must identify chemokines and their receptors involved in T-cell migration toward tumor cells. METHODS: To identify chemokine and chemokine receptors involved in T-cell migration toward CRC cells, we have used our previously published three-dimensional organotypic CRC culture system. Organotypic culture was initiated with a layer of fetal fibroblast cells mixed with collagen matrix in a 24 well tissue culture plate. A layer of CRC cells was placed on top of the fibroblast-collagen layer which was followed by a separating layer of fibroblasts in collagen matrix. Anti-CRC specific cytotoxic T lymphocytes (CTLs) mixed with fibroblasts in collagen matrix were placed on top of the separating layer. Excess chemokine ligand (CCL) or Abs to chemokine or chemokine receptor (CCR) were used in migration inhibition assays to identify the chemokine and the receptor involved in CTL migration. RESULTS: Inclusion of excess CCL2 in T-cell layer or Ab to CCL2 in separating layer of collagen fibroblasts blocked the migration of CTLs toward tumor cells and in turn significantly inhibited tumor cell apoptosis. Also, Ab to CCR2 in the separating layer of collagen and fibroblasts blocked the migration of CTLs toward tumor cells and subsequently inhibited tumor cell apoptosis. Expression of CCR2 in four additional CRC patients' lymphocytes isolated from infiltrating tumor tissues suggests their role in migration in other CRC patients. CONCLUSIONS: Our data suggest that CCL2 secreted by tumor cells and CCR2 receptors on CTLs are involved in migration of CTLs towards tumor. Gene therapy of tumor cells with CCL2 or CCL2/anti-tumor Ab fusion proteins may attract CTLs that potentially could inhibit tumor growth.


Assuntos
Movimento Celular , Quimiocina CCL2/metabolismo , Neoplasias do Colo/patologia , Receptores CCR2/metabolismo , Linfócitos T Citotóxicos/patologia , Animais , Apoptose , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Humanos , Linfócitos do Interstício Tumoral/patologia , Camundongos , Fenótipo , Fatores de Tempo
7.
Int J Cancer ; 127(5): 1124-30, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20027629

RESUMO

Immunotherapy of colorectal carcinoma (CRC) has great promise as the presence of T lymphocytes in CRC tissues in situ is correlated with reduced recurrence and increased survival. Thus, identification of the antigens recognized by T cells of CRC patients may permit development of vaccines with potential benefit for these patients. Using expression cloning, we identified the antigen, nucleophosmin (Npm), recognized by an HLA-A1 restricted cytotoxic T lymphocyte (CTL) line derived from the peripheral blood mononuclear cells (PBMC) of a rectal cancer patient. A decamer peptide derived from the Npm sequence sensitized peptide-pulsed HLA-A1 positive cells to lysis by the CTL line. The peptide also induced proliferative and cytotoxic T lymphocytes in the PBMC of 4 of 6 CRC patients, which lysed HLA-A1 positive peptide-pulsed target cells and CRC cells endogenously expressing Npm. Overexpression of Npm by tumors of various histological types, recognition of the antigen by T cells derived from different CRC patients and association of the antigen with poor prognostic outcome make it a promising target for immunotherapeutic intervention in cancer patients.


Assuntos
Antígeno HLA-A1/imunologia , Proteínas Nucleares/imunologia , Fragmentos de Peptídeos/farmacologia , Neoplasias Retais/imunologia , Linfócitos T Citotóxicos/imunologia , Apresentação de Antígeno , Antígenos de Neoplasias/imunologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Células Cultivadas , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Feminino , Humanos , Imunoterapia , Ativação Linfocitária , Melanoma/imunologia , Melanoma/patologia , Nucleofosmina , Fragmentos de Peptídeos/imunologia , Neoplasias Retais/patologia
8.
Cancer Immunol Immunother ; 56(3): 359-70, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16783574

RESUMO

Adoptive immunotherapy of cancer patients with cytolytic T lymphocytes (CTL) has been hampered by the inability of the CTL to home into tumors in vivo. Chemokines can attract T lymphocytes to the tumor site, as demonstrated in animal models, but the role of chemokines in T-lymphocyte trafficking toward human tumor cells is relatively unexplored. In the present study, the role of chemokines and their receptors in the migration of a colon carcinoma (CC) patient's CTL toward autologous tumor cells has been studied in a novel three-dimensional organotypic CC culture. CTL migration was mediated by chemokine receptor CXCR3 expressed by the CTL and CXCL11 chemokine secreted by the tumor cells. Excess CXCL11 or antibodies to CXCL11 or CXCR3 inhibited migration of CTL to tumor cells. T cell and tumor cell analyses for CXCR3 and CXCL11 expression, respectively, in ten additional CC samples, may suggest their involvement in other CC patients. Our studies, together with previous studies indicating angiostatic activity of CXCL11, suggest that CXCL11 may be useful as an immunotherapeutic agent for cancer patients when transduced into tumor cells or fused to tumor antigen-specific Ab.


Assuntos
Movimento Celular/imunologia , Quimiocinas CXC/imunologia , Neoplasias do Colo/imunologia , Receptores de Quimiocinas/imunologia , Linfócitos T Citotóxicos/imunologia , Apoptose/imunologia , Linhagem Celular Tumoral , Quimiocina CXCL11 , Quimiocinas CXC/biossíntese , Citocinas/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Fenótipo , Receptores CXCR3 , Receptores de Quimiocinas/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Técnicas de Cultura de Tecidos
9.
Cancer Biol Ther ; 5(10): 1304-12, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16929176

RESUMO

Our previous analysis of the role of chemokines in T lymphocyte trafficking toward human tumor cells revealed the migration of a melanoma patient's cytotoxic T lymphocytes (CTL) toward autologous tumor cells, resulting in tumor cell apoptosis, in an organotypic melanoma culture. CTL migration was mediated by CX chemokine receptor (CXCR) 4 expressed by the CTL and CX chemokine ligand (CXCL) 12 secreted by the tumor cells, as evidenced by blockage of CTL migration by antibodies to CXCL12 or CXCR4, high concentrations of CXCL12 or small molecule CXCR4 antagonist. Here, we present the results of T cell migration in one additional melanoma patient and T cell and tumor cell analyses for CXCR4 and CXCL12 expression, respectively, in 12 additional melanoma patients, indicating the preferential role of CXCR4 and CXCL12 in CTL migration toward melanoma cells. These studies add to the increasing body of evidence suggesting that CXCL12 is a potent chemoattractant for T cells.


Assuntos
Quimiocinas CXC/imunologia , Melanoma/imunologia , Receptores CXCR4/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T/imunologia , Linhagem Celular Tumoral , Movimento Celular , Quimiocina CXCL12 , Quimiotaxia , Citotoxicidade Imunológica , Humanos , Melanoma/secundário
10.
Eur J Immunol ; 36(2): 457-67, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16421945

RESUMO

Studies in experimental animal models have demonstrated that chemokines produced by tumor cells attract chemokine receptor-positive T lymphocytes into the tumor area. However, in cancer patients, the role of chemokines in T lymphocyte trafficking toward human tumor cells is relatively unexplored. In the present study, the migration of a melanoma patient's CTL toward autologous tumor cells has been studied in a novel three-dimensional organotypic melanoma culture. In this model, CTL migrated toward tumor cells, resulting in tumor cell apoptosis. CTL migration was mediated by the CC chemokine receptor (CCR)4 expressed by the CTL and the CC chemokine ligand (CCL)2 secreted by the tumor cells, as evidenced by blockage of CTL migration by CCL2 or antibodies to CCL2 or CCR4. These results were confirmed in a Transwell migration assay in which the CTL actively migrated toward isolated CCL2 and migration was inhibited by anti-CCR4 antibody. These studies, together with previous studies in mice indicating regression of CCL2-transduced tumor cells, suggest that CCL2 may be useful as an immunotherapeutic agent for cancer patients.


Assuntos
Apoptose/imunologia , Quimiocina CCL2/imunologia , Quimiotaxia/imunologia , Melanoma/imunologia , Receptores de Quimiocinas/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Apoptose/efeitos dos fármacos , Técnicas de Cultura de Células , Quimiocina CCL2/uso terapêutico , Quimiotaxia/efeitos dos fármacos , Feminino , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Camundongos , Receptores CCR4 , Linfócitos T Citotóxicos/patologia , Células Tumorais Cultivadas
11.
J Immunol ; 174(9): 5856-63, 2005 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15843590

RESUMO

Studies in experimental animal models have demonstrated that chemokines produced by tumor cells attract chemokine receptor-positive T lymphocytes into the tumor area, which may lead to tumor growth inhibition in vitro and in vivo. However, in cancer patients, the role of chemokines in T lymphocyte trafficking toward human tumor cells is relatively unexplored. In the present study, the role of chemokines and their receptors in the migration of a melanoma patient's CTL toward autologous tumor cells has been studied in a novel organotypic melanoma culture, consisting of a bottom layer of collagen type I with embedded fibroblasts followed successively by a tumor cell layer, collagen/fibroblast separating layer, and, finally, a top layer of collagen with embedded fibroblasts and T cells. In this model, CTL migrated from the top layer through the separating layer toward tumor cells, resulting in tumor cell apoptosis. CTL migration was mediated by chemokine receptor CXCR4 expressed by the CTL and CXCL12 (stromal cell-derived factor 1alpha) secreted by tumor cells, as evidenced by blockage of CTL migration by Abs to CXCL12 or CXCR4, high concentrations of CXCL12 or small molecule CXCR4 antagonist. These studies, together with studies in mice indicating regression of CXCL12-transduced tumor cells, followed by regression of nontransduced challenge tumor cells, suggest that CXCL12 may be useful as an immunotherapeutic agent for cancer patients, when transduced into tumor cells, or fused to anti-tumor Ag Ab or tumor Ag.


Assuntos
Quimiocinas CXC/fisiologia , Quimiotaxia de Leucócito/imunologia , Melanoma/imunologia , Melanoma/patologia , Receptores CXCR4/fisiologia , Linfócitos T Citotóxicos/imunologia , Adulto , Apoptose/imunologia , Linhagem Celular Tumoral , Quimiocina CXCL12 , Quimiocinas CXC/biossíntese , Técnicas de Cocultura , Humanos , Imunofenotipagem , Células K562 , Teste de Cultura Mista de Linfócitos , Masculino , Técnicas de Cultura de Órgãos , Receptores CXCR4/biossíntese , Células Estromais/imunologia , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/metabolismo
12.
Cancer Res ; 62(18): 5267-72, 2002 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-12234995

RESUMO

Cancer patients often develop CTLs that lyse autologous tumor cells in culture. However, tumors can progress in vivo despite the presence of CTLs. Various mechanisms have been reported to down-modulate CTL functions. In this study, the role of CD4+/CD25+ regulatory T cells in CTL induction and proliferation of established CTLs was investigated in a patient with CRC. CD4+ cytotoxic and regulatory T-cell lines were derived from the peripheral blood mononuclear cells of the same patient in mixed-lymphocyte tumor culture. The cytotoxic T-cell line and a clonal derivative specifically lysed the autologous tumor cells but not the B lymphocytes. Only HLA-A1-matched allogeneic CRC cells were lysed by the CTL clone. The clone produced IFN-gamma and TNF-alpha. The regulatory CD4+/CD25+ T-cell line was tumor cell-dependent in its growth but did not lyse autologous tumor cells. This T-cell line suppressed pokeweed mitogen responses of allogeneic lymphocytes, proliferative activity of the established, autologous CTLs, and induction of CTLs in autologous, freshly isolated peripheral blood mononuclear cells. The immunosuppressive effect of the CD4+/CD25+ regulatory T cells was mediated by transforming growth factor-beta and did not require cell-to-cell contact. Thus, although CRC patients can develop specific CTLs against their tumors, the development of regulatory T cells may allow the escape of tumor cells from immune surveillance by the CTLs in vivo.


Assuntos
Antígenos CD4/imunologia , Neoplasias Colorretais/imunologia , Receptores de Interleucina-2/imunologia , Linfócitos T Citotóxicos/imunologia , Fator de Crescimento Transformador beta/imunologia , Animais , Técnicas de Cocultura , Antígeno HLA-A1/imunologia , Humanos , Ativação Linfocitária/imunologia , Camundongos , Camundongos Nus , Camundongos SCID , Células Tumorais Cultivadas
13.
J Infect Dis ; 185(5): 686-90, 2002 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11865427

RESUMO

Development of a vaccine for prevention of congenital cytomegalovirus (CMV) disease is a priority. This study evaluated a "prime-boost" strategy by comparing the safety and immunogenicity of 3 doses of subunit CMV glycoprotein B (gB) vaccine plus MF59 (a squalene-in-water emulsion), 2 doses of a canarypox recombinant vaccine expressing CMVgB (ALVAC-CMVgB) followed by 2 doses of the subunit gB vaccine, 3 doses of both vaccines administered concomitantly, and placebo in 105 healthy, CMV-seronegative adults. Systemic adverse events were rare, but local reactions were common in all groups. After the first subunit vaccination, neutralizing antibody titers in the prime-boost group were comparable to those in subjects receiving 2 subunit vaccinations, indicating a priming effect of ALVAC-CMVgB. However, after the final dose, antibody and cell-mediated immune responses were not significantly different among the groups. All 3 vaccine regimens induced high-titer antibody and lymphoproliferative responses, but no benefit for priming or simultaneous vaccination was detected.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/prevenção & controle , Vacinas contra Citomegalovirus/imunologia , Ativação Linfocitária , Vacinas de Subunidades Antigênicas/imunologia , Proteínas do Envelope Viral/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adolescente , Adulto , Vacinas contra Citomegalovirus/administração & dosagem , Humanos , Esquemas de Imunização , Imunização Secundária , Pessoa de Meia-Idade , Polissorbatos/administração & dosagem , Esqualeno/administração & dosagem , Esqualeno/imunologia , Vacinação , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Vacinas Virais/administração & dosagem , Vacinas Virais/genética , Vacinas Virais/imunologia
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