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1.
Nat Commun ; 15(1): 216, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172101

RESUMO

Post-acute sequelae of SARS-CoV-2 (PASC) is a significant public health concern. We describe Patient Reported Outcomes (PROs) on 590 participants prospectively assessed from hospital admission for COVID-19 through one year after discharge. Modeling identified 4 PRO clusters based on reported deficits (minimal, physical, mental/cognitive, and multidomain), supporting heterogenous clinical presentations in PASC, with sub-phenotypes associated with female sex and distinctive comorbidities. During the acute phase of disease, a higher respiratory SARS-CoV-2 viral burden and lower Receptor Binding Domain and Spike antibody titers were associated with both the physical predominant and the multidomain deficit clusters. A lower frequency of circulating B lymphocytes by mass cytometry (CyTOF) was observed in the multidomain deficit cluster. Circulating fibroblast growth factor 21 (FGF21) was significantly elevated in the mental/cognitive predominant and the multidomain clusters. Future efforts to link PASC to acute anti-viral host responses may help to better target treatment and prevention of PASC.


Assuntos
Líquidos Corporais , COVID-19 , Feminino , Humanos , SARS-CoV-2 , COVID-19/complicações , Linfócitos B , Progressão da Doença , Fenótipo
2.
Clin Pharmacol Ther ; 112(2): 224-232, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34551122

RESUMO

Clinicians and patients often try a treatment for an initial period to inform longer-term therapeutic decisions. A more rigorous approach involves N-of-1 trials. In these single-patient crossover trials, typically conducted in patients with chronic conditions, individual patients are given candidate treatments in a double-blinded, random sequence of alternating periods to determine the most effective treatment for that patient. However, to date, these trials are rarely done outside of research settings and have not been integrated into general care where they could offer substantial benefit. Designating this classical, N-of-1 trial design as type 1, there also are new and evolving uses of N-of-1 trials that we designate as type 2. In these, rather than focusing on optimizing treatment for chronic diseases when multiple approved choices are available, as is typical of type 1, a type 2 N-of-1 trial tests treatments designed specifically for a patient with a rare disease, to facilitate personalized medicine. While the aims differ, both types face the challenge of collecting individual-patient evidence using standard, trusted, widely accepted methods. To fulfill their potential for producing both clinical and research benefits, and to be available for wide use, N-of-1 trials will have to fit into the current healthcare ecosystem. This will require generalizable and accepted processes, platforms, methods, and standards. This also will require sustainable value-based arrangements among key stakeholders. In this article, we review opportunities, stakeholders, issues, and possible approaches that could support general use of N-of-1 trials and deliver benefit to patients and the healthcare enterprise. To assess and expand the benefits of N-of-1 trials, we propose multistakeholder meetings, workshops, and the generation of methods, standards, and platforms that would support wider availability and the value of N-of-1 trials.


Assuntos
Atenção à Saúde , Ecossistema , Humanos , Resultado do Tratamento
3.
Pediatr Rheumatol Online J ; 19(1): 40, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33752695

RESUMO

BACKGROUND: Pediatric patients with juvenile idiopathic arthritis (JIA) are at risk for a lower health-related quality of life compared to their healthy peers. Remote monitoring of health-related quality of life using electronic patient-reported outcomes could provide important information to treating physicians. The aim of this study was to investigate if self-assessment with the EuroQol five-dimensional 'youth' questionnaire with five levels (EQ-5D-Y-5 L) inside a mobile E-health application could identify JIA patients in need of possible treatment adjustments. METHODS: The EQ-5D-Y-5 L was completed via a mobile application (Reuma2Go) between October 2017 and January 2019. The clinical juvenile arthritis disease activity score with 71 joint count (cJADAS-71) was reported at every corresponding visit as reference for disease activity. Previously described cJADAS-71 thresholds were used to identify patients in possible need of treatment adjustments. Discriminatory power of the EQ-5D-Y-5 L was assessed by ROC-curves and diagnostic characteristics. RESULTS: Sixty-eight JIA patients completed the EQ-5D-Y-5 L questionnaire. Median cJADAS-71 indicated low disease activity overall in the studied population. ROC curves and diagnostic characteristics demonstrated that self-assessment with the EQ-5D-Y-5 L could distinguish between patients with inactive disease (or minimal disease activity) and moderate to high disease activity with good accuracy (87%), sensitivity (85%), specificity (89%) and negative predictive value (86%). CONCLUSIONS: Results demonstrate that the EQ-5D-Y-5 L was able to identify JIA patients in need of possible treatment adjustments in our studied population. Remote monitoring of health-related quality of life and patient-reported outcomes via E-health applications could provide important additional information to determine the frequency of clinical visits, assess therapeutic efficacy and guide treat-to-target strategies in pediatric patients with JIA.


Assuntos
Artrite Juvenil/diagnóstico , Autoavaliação Diagnóstica , Aplicativos Móveis , Monitorização Ambulatorial/métodos , Qualidade de Vida , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos
5.
Clin Pharmacol Ther ; 105(4): 857-866, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30610746

RESUMO

Efficacy trials, designed to gain regulatory marketing approval, evaluate drugs in optimally selected patients under advantageous conditions for relatively short time periods. Effectiveness trials, designed to evaluate use in usual practice, assess treatments among more typical patients in real-world conditions with longer follow-up periods. In "efficacy-to-effectiveness (E2E) trials," if the initial efficacy trial component is positive, the trial seamlessly transitions to an effectiveness trial component to efficiently yield both types of evidence. Yet more time could be saved by simultaneously addressing efficacy and effectiveness in an "efficacy and effectiveness too (EE2) trial." Additionally, hybrids of the E2E and EE2 approaches with differing degrees of overlap of the two components could allow flexibility for specific drug development needs. In planning EE2 trials, each stakeholder's current and future needs, incentives, and perspective must be considered. Although challenging, the ultimate benefits to stakeholders, the health system, and the public should justify this effort.


Assuntos
Ensaios Clínicos como Assunto/legislação & jurisprudência , Aprovação de Drogas/legislação & jurisprudência , Desenvolvimento de Medicamentos/legislação & jurisprudência , Projetos de Pesquisa/legislação & jurisprudência , Análise Custo-Benefício/legislação & jurisprudência , Humanos , Marketing/legislação & jurisprudência , Seleção de Pacientes , Resultado do Tratamento
9.
J Immunol ; 187(2): 1039-46, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21653833

RESUMO

Multiple sclerosis (MS) is an autoimmune disease characterized by infiltration of pathogenic immune cells in the CNS resulting in destruction of the myelin sheath and surrounding axons. We and others have previously measured the frequency of human myelin-reactive T cells in peripheral blood. Using T cell cloning techniques, a modest increase in the frequency of myelin-reactive T cells in patients as compared with control subjects was observed. In this study, we investigated whether myelin oligodendrocyte glycoprotein (MOG)-specific T cells could be detected and their frequency was measured using DRB1*0401/MOG(97-109(107E-S)) tetramers in MS subjects and healthy controls expressing HLA class II DRB1*0401. We defined the optimal culture conditions for expansion of MOG-reactive T cells upon MOG peptide stimulation of PMBCs. MOG(97-109)-reactive CD4(+) T cells, isolated with DRB1*0401/MOG(97-109) tetramers, and after a short-term culture of PMBCs with MOG(97-109) peptides, were detected more frequently from patients with MS as compared with healthy controls. T cell clones from single cell cloning of DRB1*0401/MOG(97-109(107E-S)) tetramer(+) cells confirmed that these T cell clones were responsive to both the native and the substituted MOG peptide. These data indicate that autoantigen-specific T cells can be detected and enumerated from the blood of subjects using class II tetramers, and the frequency of MOG(97-109)-reactive T cells is greater in patients with MS as compared with healthy controls.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos HLA-DR/metabolismo , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Glicoproteína Associada a Mielina/metabolismo , Fragmentos de Peptídeos/metabolismo , Adulto , Idoso , Substituição de Aminoácidos/genética , Substituição de Aminoácidos/imunologia , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/patologia , Comunicação Celular/genética , Comunicação Celular/imunologia , Linhagem Celular Transformada , Células Cultivadas , Epitopos de Linfócito T/biossíntese , Epitopos de Linfócito T/genética , Feminino , Frequência do Gene/imunologia , Antígenos HLA-DR/genética , Cadeias HLA-DRB1 , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/genética , Glicoproteína Mielina-Oligodendrócito , Ligação Proteica/genética , Ligação Proteica/imunologia , Multimerização Proteica/genética , Multimerização Proteica/imunologia
10.
N Engl J Med ; 363(3): 221-32, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20647199

RESUMO

BACKGROUND: Cyclophosphamide and glucocorticoids have been the cornerstone of remission-induction therapy for severe antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis for 40 years. Uncontrolled studies suggest that rituximab is effective and may be safer than a cyclophosphamide-based regimen. METHODS: We conducted a multicenter, randomized, double-blind, double-dummy, noninferiority trial of rituximab (375 mg per square meter of body-surface area per week for 4 weeks) as compared with cyclophosphamide (2 mg per kilogram of body weight per day) for remission induction. Glucocorticoids were tapered off; the primary end point was remission of disease without the use of prednisone at 6 months. RESULTS: Nine centers enrolled 197 ANCA-positive patients with either Wegener's granulomatosis or microscopic polyangiitis. Baseline disease activity, organ involvement, and the proportion of patients with relapsing disease were similar in the two treatment groups. Sixty-three patients in the rituximab group (64%) reached the primary end point, as compared with 52 patients in the control group (53%), a result that met the criterion for noninferiority (P<0.001). The rituximab-based regimen was more efficacious than the cyclophosphamide-based regimen for inducing remission of relapsing disease; 34 of 51 patients in the rituximab group (67%) as compared with 21 of 50 patients in the control group (42%) reached the primary end point (P=0.01). Rituximab was also as effective as cyclophosphamide in the treatment of patients with major renal disease or alveolar hemorrhage. There were no significant differences between the treatment groups with respect to rates of adverse events. CONCLUSIONS: Rituximab therapy was not inferior to daily cyclophosphamide treatment for induction of remission in severe ANCA-associated vasculitis and may be superior in relapsing disease. (Funded by the National Institutes of Allergy and Infectious Diseases, Genentech, and Biogen; ClinicalTrials.gov number, NCT00104299.)


Assuntos
Anticorpos Monoclonais/uso terapêutico , Ciclofosfamida/uso terapêutico , Granulomatose com Poliangiite/tratamento farmacológico , Imunossupressores/uso terapêutico , Poliangiite Microscópica/tratamento farmacológico , Administração Oral , Idoso , Anticorpos Anticitoplasma de Neutrófilos/sangue , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Murinos , Linfócitos B/efeitos dos fármacos , Ciclofosfamida/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Análise de Intenção de Tratamento , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Prednisona/uso terapêutico , Qualidade de Vida , Indução de Remissão , Rituximab
11.
J Clin Invest ; 120(6): 1848-61, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20501943

RESUMO

Identifying transplant recipients in whom immunological tolerance is established or is developing would allow an individually tailored approach to their posttransplantation management. In this study, we aimed to develop reliable and reproducible in vitro assays capable of detecting tolerance in renal transplant recipients. Several biomarkers and bioassays were screened on a training set that included 11 operationally tolerant renal transplant recipients, recipient groups following different immunosuppressive regimes, recipients undergoing chronic rejection, and healthy controls. Highly predictive assays were repeated on an independent test set that included 24 tolerant renal transplant recipients. Tolerant patients displayed an expansion of peripheral blood B and NK lymphocytes, fewer activated CD4+ T cells, a lack of donor-specific antibodies, donor-specific hyporesponsiveness of CD4+ T cells, and a high ratio of forkhead box P3 to alpha-1,2-mannosidase gene expression. Microarray analysis further revealed in tolerant recipients a bias toward differential expression of B cell-related genes and their associated molecular pathways. By combining these indices of tolerance as a cross-platform biomarker signature, we were able to identify tolerant recipients in both the training set and the test set. This study provides an immunological profile of the tolerant state that, with further validation, should inform and shape drug-weaning protocols in renal transplant recipients.


Assuntos
Biomarcadores/metabolismo , Tolerância Imunológica/imunologia , Imunossupressores/imunologia , Transplante de Rim/imunologia , Humanos , Tolerância Imunológica/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Doadores de Tecidos
12.
J Clin Invest ; 120(6): 1836-47, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20501946

RESUMO

Establishing long-term allograft acceptance without the requirement for continuous immunosuppression, a condition known as allograft tolerance, is a highly desirable therapeutic goal in solid organ transplantation. Determining which recipients would benefit from withdrawal or minimization of immunosuppression would be greatly facilitated by biomarkers predictive of tolerance. In this study, we identified the largest reported cohort to our knowledge of tolerant renal transplant recipients, as defined by stable graft function and receiving no immunosuppression for more than 1 year, and compared their gene expression profiles and peripheral blood lymphocyte subsets with those of subjects with stable graft function who are receiving immunosuppressive drugs as well as healthy controls. In addition to being associated with clinical and phenotypic parameters, renal allograft tolerance was strongly associated with a B cell signature using several assays. Tolerant subjects showed increased expression of multiple B cell differentiation genes, and a set of just 3 of these genes distinguished tolerant from nontolerant recipients in a unique test set of samples. This B cell signature was associated with upregulation of CD20 mRNA in urine sediment cells and elevated numbers of peripheral blood naive and transitional B cells in tolerant participants compared with those receiving immunosuppression. These results point to a critical role for B cells in regulating alloimmunity and provide a candidate set of genes for wider-scale screening of renal transplant recipients.


Assuntos
Linfócitos B/imunologia , Tolerância Imunológica/imunologia , Transplante de Rim/imunologia , Tolerância ao Transplante/genética , Biomarcadores , Perfilação da Expressão Gênica , Humanos , Terapia de Imunossupressão/métodos , Ativação Linfocitária/imunologia , Tolerância ao Transplante/imunologia
13.
Pediatr Clin North Am ; 57(2): 523-38, table of contents, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20371050

RESUMO

In the clinical arena of transplantation, tolerance remains, for the most part, a concept rather than a reality. Although modern immunosuppression regimens have effectively handled acute rejection, nearly all organs except the liver commonly suffer chronic immunologic damage that impairs organ function, threatening patient and allograft survival. In addition to the imperfect control of the donor-directed immune response, there are additional costs. First, there is the burden of mortality from infection and malignancy that can be directly attributed to a crippled immune system. Second, there are insidious effects on renal function, cardiovascular profile (hypertension, hyperglycemia, and dyslipidemia), bone health, growth, psychological and neurocognitive development, and overall quality of life. It is likely that the full consequences of lifelong immunosuppression on our pediatric transplant recipients will not be fully appreciated until survival routinely extends beyond 1 or 2 decades after transplantation. Therefore, it can be argued that the holy grail of transplantation tolerance is of the utmost importance to children who undergo solid organ transplantation.


Assuntos
Transplante de Órgãos , Tolerância ao Transplante , Biomarcadores , Criança , Humanos , Transplante de Rim , Transplante de Fígado , Modelos Imunológicos , Monitorização Imunológica , Imunologia de Transplantes , Tolerância ao Transplante/imunologia
14.
BMC Immunol ; 10: 52, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19785746

RESUMO

BACKGROUND: Growing knowledge about cellular interactions in the immune system, including the central role of cytokine networks, has lead to new treatments using monoclonal antibodies that block specific components of the immune system. Systemic cytokine concentrations can serve as surrogate outcome parameters of these interventions to study inflammatory pathways operative in patients in vivo. This is now possible due to novel technologies such as multiplex immunoassays (MIA) that allows detection of multiple cytokines in a single sample. However, apparently trivial underappreciated processes, (sample handling and storage, interference of endogenous plasma proteins) can greatly impact the reliability and reproducibility of cytokine detection.Therefore we set out to investigate several processes that might impact cytokine profiles such as blood collecting tubes, duration of storage, and number of freeze thawing cycles. RESULTS: Since under physiological conditions cytokine concentrations normally are low or undetectable we spiked cytokines in the various plasma and serum samples. Overall recoveries ranged between 80-120%. Long time storage showed cytokines are stable for a period up to 2 years of storage at -80 degrees C. After 4 years several cytokines (IL-1alpha, IL-1beta, IL-10, IL-15 and CXCL8) degraded up to 75% or less of baseline values. Furthermore we show that only 2 out of 15 cytokines remained stable after several freeze-thawing cycles. We also demonstrate implementation of an internal control for multiplex cytokine immunoassays. CONCLUSION: All together we show parameters which are essential for measurement of cytokines in the context of clinical trials.


Assuntos
Citocinas/metabolismo , Imunoensaio , Leucócitos Mononucleares/metabolismo , Coleta de Amostras Sanguíneas/efeitos adversos , Células Cultivadas , Ensaios Clínicos como Assunto , Ácido Edético/metabolismo , Congelamento/efeitos adversos , Heparina/metabolismo , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Imunoensaio/normas , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Lipopolissacarídeos/metabolismo , Fito-Hemaglutininas/metabolismo , Estabilidade Proteica , Padrões de Referência , Reprodutibilidade dos Testes
15.
Clin Immunol ; 132(2): 166-73, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19443276

RESUMO

Anti-CD3 mAbs may prolong beta cell function up to 2 years in patients with new onset Type 1 diabetes (T1DM). A randomized open label trial of anti-CD3 mAb, Teplizumab, in T1DM was stopped after 10 subjects because of increased adverse events than in a previous trial related with higher dosing of drug. Teplizumab caused transient reduction in circulating T cells, but the recovered cells were not new thymic emigrants because T cell receptor excision circles were not increased. There was a trend for reduced loss of C-peptide over 2 years with drug treatment (p=0.1), and insulin use was lower (p<0.001). In 4 drug-treated subjects followed up to 60 months, C-peptide responses were maintained. We conclude that increased doses of Teplizumab are associated with greater adverse events without improved efficacy. The drug may marginate rather than deplete T cells. C-peptide levels may remain detectable up to 5 years after treatment.


Assuntos
Complexo CD3/imunologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina/metabolismo , Muromonab-CD3/uso terapêutico , Adolescente , Anticorpos Monoclonais Humanizados , Peptídeo C/metabolismo , Criança , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/patologia , Exantema/induzido quimicamente , Feminino , Febre/induzido quimicamente , Seguimentos , Gastroenteropatias/induzido quimicamente , Humanos , Hipoglicemiantes/metabolismo , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Masculino , Muromonab-CD3/efeitos adversos , Náusea/induzido quimicamente , Resultado do Tratamento , Vômito/induzido quimicamente
16.
Bioinformatics ; 25(1): 48-53, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19015138

RESUMO

MOTIVATION: As the use of microarrays in human studies continues to increase, stringent quality assurance is necessary to ensure accurate experimental interpretation. We present a formal approach for microarray quality assessment that is based on dimension reduction of established measures of signal and noise components of expression followed by parametric multivariate outlier testing. RESULTS: We applied our approach to several data resources. First, as a negative control, we found that the Affymetrix and Illumina contributions to MAQC data were free from outliers at a nominal outlier flagging rate of alpha=0.01. Second, we created a tunable framework for artificially corrupting intensity data from the Affymetrix Latin Square spike-in experiment to allow investigation of sensitivity and specificity of quality assurance (QA) criteria. Third, we applied the procedure to 507 Affymetrix microarray GeneChips processed with RNA from human peripheral blood samples. We show that exclusion of arrays by this approach substantially increases inferential power, or the ability to detect differential expression, in large clinical studies. AVAILABILITY: http://bioconductor.org/packages/2.3/bioc/html/arrayMvout.html and http://bioconductor.org/packages/2.3/bioc/html/affyContam.html affyContam (credentials: readonly/readonly)


Assuntos
Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Ambrosia/imunologia , Ensaios Clínicos como Assunto , Regulação da Expressão Gênica , Humanos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Análise Multivariada , Análise de Componente Principal
17.
Cytometry B Clin Cytom ; 76(2): 69-78, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18690669

RESUMO

BACKGROUND: FoxP3 has become a key identifier of regulatory T cells. Investigators have used a variety of antibodies and methods for detecting FoxP3 by flow cytometry. To standardize FoxP3 antibody staining for use in clinical trial samples, we tested various antibodies from different vendors, cell preparation protocols and fix/perm reagents, and cell isolation procedures. Using this optimized staining protocol, we evaluated clinical specimens from patients with multiple sclerosis (MS) or type 1 diabetes. METHODS: FoxP3 antibodies from eBioscience (236A/E7 and PCH101) and BioLegend (206D) were evaluated along with their respective methods and fix/perm reagents for preparation and staining of FoxP3 for flow cytometry. Fresh washed blood and frozen or fresh PBMC were evaluated. Upon optimization of the protocol, clinical samples (frozen PBMC) from patients with MS or type 1 diabetes and healthy control donors were evaluated with the BioLegend antibody. RESULTS: Clone 206D from BioLegend yielded optimal staining and the fix/perm reagents from both eBioscience and BioLegend were comparable. Data were also comparable between cells separated by Ficoll (fresh or frozen) and washed blood samples, allowing this protocol to be applicable to different types of samples. We validated this protocol using clinical samples and saw a significant increase in FoxP3 expression in the patients with type 1 diabetes but not in the MS. CONCLUSIONS: The results from this study will allow the assessment of FoxP3 by flow cytometry on samples from clinical sites that are analyzed in real time on fresh blood or frozen PBMC.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Citometria de Fluxo/métodos , Imunofluorescência/métodos , Fatores de Transcrição Forkhead/análise , Fatores de Transcrição Forkhead/metabolismo , Linfócitos T Reguladores/metabolismo , Anticorpos , Biomarcadores/análise , Biomarcadores/sangue , Células Clonais/citologia , Células Clonais/imunologia , Células Clonais/metabolismo , Criopreservação/métodos , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Ficoll , Humanos , Tolerância Imunológica/imunologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Coloração e Rotulagem/métodos , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Fixação de Tecidos/métodos , Regulação para Cima/imunologia
18.
BMC Genomics ; 9: 474, 2008 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-18847473

RESUMO

BACKGROUND: RNA isolation and purification steps greatly influence the results of gene expression profiling. There are two commercially available products for whole blood RNA collection, PAXgene and Tempus blood collection tubes, and each comes with their own RNA purification method. In both systems the blood is immediately lysed when collected into the tube and RNA stabilized using proprietary reagents. Both systems enable minimal blood handling procedures thus minimizing the risk of inducing changes in gene expression through blood handling or processing. Because the RNA purification steps could influence the total RNA pool, we examined the impact of RNA isolation, using the PAXgene or Tempus method, on gene expression profiles. RESULTS: Using microarrays as readout of RNA from stimulated whole blood we found a common set of expressed transcripts in RNA samples from either PAXgene or Tempus. However, we also found several to be uniquely expressed depending on the type of collection tube, suggesting that RNA purification methods impact results of differential gene expression profiling. Specifically, transcripts for several known PHA-inducible genes, including IFNgamma, IL13, IL2, IL3, and IL4 were found to be upregulated in stimulated vs. control samples when RNA was isolated using the ABI Tempus method, but not using the PAXgene method (p < 0.01, FDR corrected). Sequenom Quantiative Gene Expression (QGE) (SanDiego, CA) measures confirmed IL2, IL4 and IFNgamma up-regulation in Tempus purified RNA from PHA stimulated cells while only IL2 was up-regulated using PAXgene purified (p < 0.05). CONCLUSION: Here, we demonstrate that peripheral blood RNA isolation methods can critically impact differential expression results, particularly in the clinical setting where fold-change differences are typically small and there is inherent variability within biological cohorts. A modified method based upon the Tempus system was found to provide high yield, good post-hybridization array quality, low variability in expression measures and was shown to produce differential expression results consistent with the predicted immunologic effects of PHA stimulation.


Assuntos
Coleta de Amostras Sanguíneas/métodos , Perfilação da Expressão Gênica/métodos , RNA/sangue , RNA/isolamento & purificação , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Fito-Hemaglutininas/farmacologia , Transcrição Gênica/imunologia
19.
J Clin Invest ; 118(8): 2684-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18654643

RESUMO

Long-term allograft survival requires lifelong immunosuppression, which comes with serious side effects. Inducing immune tolerance to the transplant would enable immunosuppression withdrawal and revolutionize the quality of life of transplant recipients. In this issue of the JCI, Martínez-Llordella et al. identify a profile of biomarkers that predict tolerance in liver transplant recipients (see the related article beginning on page 2845). These findings translate into a new means for prospectively selecting liver transplant patients who would benefit from immunosuppression withdrawal and ultimately may guide development of tolerogenic therapies that allow for allograft acceptance without the use of long-term immunosuppression.


Assuntos
Tolerância Imunológica , Terapia de Imunossupressão , Transplante de Fígado/imunologia , Imunologia de Transplantes/genética , Tolerância ao Transplante/genética , Biomarcadores/metabolismo , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Humanos , Imunossupressores/administração & dosagem , Modelos Imunológicos , Seleção de Pacientes , Análise de Sobrevida
20.
J Allergy Clin Immunol ; 120(3): 688-95, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17631952

RESUMO

BACKGROUND: The combination of anti-IgE (omalizumab) therapy with ragweed injection immunotherapy for seasonal allergic rhinitis results in a significant reduction in systemic side effects and enhanced efficacy compared with immunotherapy alone. One proposed mechanism of immunotherapy is to induce regulatory antibodies that inhibit facilitated antigen presentation. OBJECTIVES: We sought to determine whether the combination protocol has a cumulative effect on inhibition of facilitated antigen presentation both during and after discontinuation of treatment. METHODS: Ragweed allergen immunotherapy with and without omalizumab therapy was tested in a 4-arm, double-blind, placebo-controlled study. Flow cytometry was used to detect serum inhibitory activity for IgE-facilitated CD23-dependent allergen binding to B cells as a surrogate marker for facilitated antigen presentation. Serum ragweed-specific IgG4 was measured by means of ELISA. RESULTS: Immunotherapy alone resulted in partial inhibition of allergen-IgE binding after 5 to 19 weeks of treatment compared with baseline (P < .01). Complete inhibition of allergen-specific IgE binding was observed in both treatment groups receiving omalizumab (P < .001). Allergen-specific IgG4 levels were only increased after immunotherapy (P < .05), both in the presence and absence of anti-IgE treatment. Combined treatment resulted in the induction of long-lasting inhibitory antibody function for up to 42 weeks compared with either treatment alone. CONCLUSION: Ragweed immunotherapy induced serum regulatory antibodies that partially blocked binding of allergen-IgE complexes to B cells. Additional treatment with anti-IgE, by directly blocking IgE binding to CD23, completely inhibited allergen-IgE binding. CLINICAL IMPLICATIONS: The combination of ragweed immunotherapy and anti-IgE resulted in prolonged inhibition of allergen-IgE binding compared with either treatment alone, events that might contribute to enhanced efficacy.


Assuntos
Antialérgicos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Dessensibilização Imunológica , Imunoglobulina E/efeitos dos fármacos , Rinite Alérgica Sazonal/terapia , Adulto , Ambrosia/imunologia , Anticorpos Anti-Idiotípicos , Anticorpos Monoclonais Humanizados , Apresentação de Antígeno/efeitos dos fármacos , Apresentação de Antígeno/imunologia , Antígenos de Plantas/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Terapia Combinada , Método Duplo-Cego , Citometria de Fluxo , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Fragmentos Fab das Imunoglobulinas/imunologia , Pessoa de Meia-Idade , Omalizumab
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