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1.
J Immunol ; 210(12): 2029-2037, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37163328

RESUMO

The intrinsic and acquired resistance to PD-1/PD-L1 immune checkpoint blockade is an important challenge for patients and clinicians because no reliable tool has been developed to predict individualized response to immunotherapy. In this study, we demonstrate the translational relevance of an ex vivo functional assay that measures the tumor cell killing ability of patient-derived CD8 T and NK cells (referred to as "cytotoxic lymphocytes," or CLs) isolated from the peripheral blood of patients with renal cell carcinoma. Patient-derived PBMCs were isolated before and after nephrectomy from patients with renal cell carcinoma. We compared the efficacy of U.S. Food and Drug Administration (FDA)-approved PD-1/PD-L1 inhibitors (pembrolizumab, nivolumab, atezolizumab) and a newly developed PD-L1 inhibitor (H1A Ab) in eliciting cytotoxic function. CL activity was improved at 3 mo after radical nephrectomy compared with baseline, and it was associated with higher circulating levels of tumor-reactive effector CD8 T cells (CD11ahighCX3CR1+GZMB+). Treatment of PBMCs with FDA-approved PD-1/PD-L1 inhibitors enhanced tumor cell killing activity of CLs, but a differential response was observed at the individual-patient level. H1A demonstrated superior efficacy in promoting CL activity compared with FDA-approved PD-1/PD-L1 inhibitors. PBMC immunophenotyping by mass cytometry revealed enrichment of effector CD8 T and NK cells in H1A-treated PBMCs and immunosuppressive regulatory T cells in atezolizumab-treated samples. Our study lays the ground for future investigation of the therapeutic value of H1A as a next-generation immune checkpoint inhibitor and the potential of measuring CTL activity in PBMCs as a tool to predict individual response to immune checkpoint inhibitors in patients with advanced renal cell carcinoma.


Assuntos
Antineoplásicos , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Leucócitos Mononucleares , Antineoplásicos/farmacologia , Linfócitos T Reguladores , Neoplasias Renais/tratamento farmacológico , Nefrectomia , Linfócitos T CD8-Positivos
2.
J Clin Microbiol ; 54(5): 1251-8, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26912758

RESUMO

This multicenter study analyzed Nocardia spp., including extraction, spectral acquisition, Bruker matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) identification, and score interpretation, using three Nocardia libraries, the Bruker, National Institutes of Health (NIH), and The Ohio State University (OSU) libraries, and compared the results obtained by each center. A standardized study protocol, 150 Nocardia isolates, and NIH and OSU Nocardia MALDI-TOF MS libraries were distributed to three centers. Following standardized culture, extraction, and MALDI-TOF MS analysis, isolates were identified using score cutoffs of ≥2.0 for species/species complex-level identification and ≥1.8 for genus-level identification. Isolates yielding a score of <2.0 underwent a single repeat extraction and analysis. The overall score range for all centers was 1.3 to 2.7 (average, 2.2 ± 0.3), with common species generally producing higher average scores than less common ones. Score categorization and isolate identification demonstrated 86% agreement between centers; 118 of 150 isolates were correctly identified to the species/species complex level by all centers. Nine strains (6.0%) were not identified by any center, and six (4.0%) of these were uncommon species with limited library representation. A categorical score discrepancy among centers occurred for 21 isolates (14.0%). There was an overall benefit of 21.2% from repeat extraction of low-scoring isolates and a center-dependent benefit for duplicate spotting (range, 2 to 8.7%). Finally, supplementation of the Bruker Nocardia MALDI-TOF MS library with both the OSU and NIH libraries increased the genus-level and species-level identification by 18.2% and 36.9%, respectively. Overall, this study demonstrates the ability of diverse clinical microbiology laboratories to utilize MALDI-TOF MS for the rapid identification of clinically relevant Nocardia spp. and to implement MALDI-TOF MS libraries developed by single laboratories across institutions.


Assuntos
Técnicas Bacteriológicas/métodos , Nocardiose/diagnóstico , Nocardiose/microbiologia , Nocardia/classificação , Nocardia/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Nocardia/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
3.
Int J Syst Evol Microbiol ; 66(8): 2929-2935, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27130323

RESUMO

Gram-stain-positive, partially acid-fast, non-spore-forming, anaerobic, catalase-positive, pleomorphic bacteria were isolated from human abscesses. Strains X1036T, X1698 and NML 120705, were recovered from a spinal abscess, a peritoneal abscess and a breast abscess respectively. A phylogenetic analysis of the 16S rRNA gene sequences showed that the strains shared 100 % similarity, and the nearest phylogenetic neighbour was Dietzia timorensis DSM 45568T (95%). Chemotaxonomic characteristics of the strains were consistent with those described for members of the suborder Corynebacterineae. Mycolic acids were detected using HPLC and one-dimensional TLC; whole-cell hydrolysates yielded meso-diaminopimelic acid with arabinose and galactose as the predominant sugars; the muramic acid acyl type was acetylated; the major menaquinone was MK-9 (96.3%); polar lipids detected were phosphatidylglycerol, phosphatidylinositol and an unknown glycophospholipid. Cellular fatty acids were hexadecanoic acid (C16 : 0), octadecenoic acid (C18 : 1ω9c) and decanoic acid (C10 : 0). Tuberculostearic acid was not detected. Based on the results of this polyphasic study, we conclude that these strains represent a novel genus and species within the suborder Corynebacterineae for which we propose the name Lawsonella clevelandensis gen. nov., sp. nov., with the type strain X1036T (=DSM 45743T=CCUG 66657T).


Assuntos
Abscesso/microbiologia , Actinobacteria/classificação , Filogenia , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Murâmicos/química , Ácidos Micólicos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Coluna Vertebral/microbiologia , Coluna Vertebral/patologia
4.
Cancer Immunol Immunother ; 63(8): 859-67, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24893858

RESUMO

A promising strategy in tumor immunotherapy is the use of activated dendritic cells as vehicles for tumor vaccines with the goal of activating anti-tumor T cell responses. Current formulations for dendritic cell-based immunotherapies have limited effects on patient survival, providing motivation for further investigation of ways to enhance dendritic cell priming of anti-tumor T cell responses. Using a brief in vitro priming model, we have found that B7-H1 expressed by activated dendritic cells is integrated during priming of naïve CD8(+) T cells and functions to limit the differentiation of effector T cell responses. CD8(+) T cells primed by B7-H1-deficient dendritic cells exhibit increased production of IFN-γ, enhanced target cell killing, and improved anti-tumor activity. Additionally, enhanced memory populations arise from CD8(+) T cells primed by B7-H1-deficient dendritic cells. Based on these findings, we suggest that early blockade of B7-H1 signaling should be investigated as a strategy to improve dendritic cell-based anti-tumor immunotherapy.


Assuntos
Antígeno B7-1/imunologia , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/imunologia , Animais , Antígeno B7-H1/metabolismo , Vacinas Anticâncer/imunologia , Diferenciação Celular/imunologia , Proliferação de Células , Células Dendríticas/imunologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
5.
Nat Commun ; 15(1): 1430, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365756

RESUMO

Both targeted therapies and immunotherapies provide benefit in resected Stage III melanoma. We hypothesized that the combination of targeted and immunotherapy given prior to therapeutic lymph node dissection (TLND) would be tolerable and drive robust pathologic responses. In NeoACTIVATE (NCT03554083), a Phase II trial, patients with clinically evident resectable Stage III melanoma received either 12 weeks of neoadjuvant vemurafenib, cobimetinib, and atezolizumab (BRAF-mutated, Cohort A, n = 15), or cobimetinib and atezolizumab (BRAF-wild-type, Cohort B, n = 15) followed by TLND and 24 weeks of adjuvant atezolizumab. Here, we report outcomes from the neoadjuvant portion of the trial. Based on intent to treat analysis, pathologic response (≤50% viable tumor) and major pathologic response (complete or near-complete, ≤10% viable tumor) were observed in 86.7% and 66.7% of BRAF-mutated and 53.3% and 33.3% of BRAF-wild-type patients, respectively (primary outcome); these exceeded pre-specified benchmarks of 50% and 30% for major pathologic response. Grade 3 and higher toxicities, primarily dermatologic, occurred in 63% during neoadjuvant treatment (secondary outcome). No surgical delays nor progression to regional unresectability occurred (secondary outcome). Peripheral blood CD8 + TCM cell expansion associated with favorable pathologic responses (exploratory outcome).


Assuntos
Anticorpos Monoclonais Humanizados , Azetidinas , Melanoma , Piperidinas , Neoplasias Cutâneas , Humanos , Melanoma/tratamento farmacológico , Melanoma/etiologia , Vemurafenib/uso terapêutico , Terapia Neoadjuvante , Proteínas Proto-Oncogênicas B-raf/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/etiologia , Mutação
6.
J Immunol ; 187(11): 5606-14, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22025548

RESUMO

An immunoinhibitory role of B7 homologue 1 (B7-H1) expressed by non-T cells has been established; however, the function of B7-H1 expressed by T cells is not clear. Peak expression of B7-H1 on Ag-primed CD8 T cells was observed during the contraction phase of an immune response. Unexpectedly, B7-H1 blockade at this stage reduced the numbers of effector CD8 T cells, suggesting B7-H1 blocking Ab may disturb an unknown function of B7-H1 expressed by CD8 T cells. To exclusively examine the role of B7-H1 expressed by T cells, we introduced B7-H1 deficiency into TCR transgenic (OT-1) mice. Naive B7-H1-deficient CD8 T cells proliferated normally following Ag stimulation; however, once activated, they underwent more robust contraction in vivo and more apoptosis in vitro. In addition, B7-H1-deficient CD8 T cells were more sensitive to Ca-dependent and Fas ligand-dependent killing by cytotoxic T lymphocytes. Activation-induced Bcl-x(L) expression was lower in activated B7-H1-deficient CD8 T cells, whereas Bcl-2 and Bim expression were comparable to the wild type. Transfer of effector B7-H1-deficient CD8 T cells failed to suppress tumor growth in vivo. Thus, upregulation of B7-H1 on primed T cells helps effector T cells survive the contraction phase and consequently generate optimal protective immunity.


Assuntos
Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/imunologia , Transferência Adotiva , Animais , Apoptose/imunologia , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Separação Celular , Sobrevivência Celular/imunologia , Feminino , Citometria de Fluxo , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
7.
Immunohorizons ; 7(1): 125-139, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656137

RESUMO

Seven different anti-PD-1 and PD-L1 mAbs are now widely used in the United States to treat a variety of cancer types, but no clinical trials have compared them directly. Furthermore, because many of these Abs do not cross-react between mouse and human proteins, no preclinical models exist in which to consider these types of questions. Thus, we produced humanized PD-1 and PD-L1 mice in which the extracellular domains of both mouse PD-1 and PD-L1 were replaced with the corresponding human sequences. Using this new model, we sought to compare the strength of the immune response generated by Food and Drug Administration-approved Abs. To do this, we performed an in vivo T cell priming assay in which anti-PD-1/L1 therapies were given at the time of T cell priming against surrogate tumor Ag (OVA), followed by subsequent B16-OVA tumor challenge. Surprisingly, both control and Ab-treated mice formed an equally robust OVA-specific T cell response at the time of priming. Despite this, anti-PD-1/L1-treated mice exhibited significantly better tumor rejection versus controls, with avelumab generating the best protection. To determine what could be mediating this, we identified the increased production of CX3CR1+PD-1+CD8+ cytotoxic T cells in the avelumab-treated mice, the same phenotype of effector T cells known to increase in clinical responders to PD-1/L1 therapy. Thus, our model permits the direct comparison of Food and Drug Administration-approved anti-PD-1/L1 mAbs and further correlates successful tumor rejection with the level of CX3CR1+PD-1+CD8 + T cells, making this model a critical tool for optimizing and better utilizing anti-PD-1/L1 therapeutics.


Assuntos
Antígeno B7-H1 , Neoplasias , Animais , Humanos , Camundongos , Anticorpos Monoclonais , Modelos Animais de Doenças , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Linfócitos T Citotóxicos , Estados Unidos , United States Food and Drug Administration , Receptor de Morte Celular Programada 1
8.
J Clin Microbiol ; 50(6): 2170-2, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22493337

RESUMO

Corynebacterium species are well-known causes of catheter-related bloodstream infections. Toxigenic strains of Corynebacterium diphtheriae cause respiratory diphtheria. We report a bloodstream infection caused by a nontoxigenic strain of C. diphtheriae and discuss the epidemiology, possible sources of the infection, and the implications of rapid species identification of corynebacteria.


Assuntos
Bacteriemia/diagnóstico , Infecções por Corynebacterium/diagnóstico , Corynebacterium diphtheriae/isolamento & purificação , Antibacterianos/farmacologia , Bacteriemia/microbiologia , Bacteriemia/patologia , Técnicas Bacteriológicas/métodos , Infecções por Corynebacterium/microbiologia , Infecções por Corynebacterium/patologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Testes de Sensibilidade Microbiana , Estados Unidos , Adulto Jovem
9.
Clin Cancer Res ; 28(14): 3021-3031, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35552651

RESUMO

PURPOSE: This phase Ib/2 trial investigated pembrolizumab-containing trimodality therapy in patients with gastroesophageal junction (GEJ) adenocarcinoma. PATIENTS AND METHODS: Patients with GEJ adenocarcinoma (cT1-3NanyM0) received neoadjuvant pembrolizumab-containing chemoradiation (CROSS regimen) followed by surgical resection and adjuvant pembrolizumab. The primary endpoints were tolerability in the first 16 patients and pathologic complete response [pCR (ypT0N0)]. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). An independent propensity-score-matched cohort (treated with CROSS without immunotherapy) was used for comparison. Exploratory analyses included immune biomarkers in the tumor microenvironment (TME) and plasma. RESULTS: We enrolled 31 eligible patients, of whom 29 received all expected doses of neoadjuvant pembrolizumab and 28 underwent R0 resection. Safety endpoints were met. The primary efficacy endpoint was not met [7/31 (22.6%) achieved pCR]. Patients with high [i.e., combined positive score (CPS) ≥ 10] baseline expression of programmed death (PD)-L1 in the TME had a significantly higher pCR rate than those with low expression [50.0% (4/8) vs. 13.6% (3/22); P = 0.046]. Patients with high PD-L1 expression also experienced longer PFS and OS than propensity-score-matched patients. Among trial patients with PD-L1 CPS < 10, unprespecified analysis explored whether extracellular vesicles (EV) could identify further responders: an elevated plasma level of PD-L1-expressing EVs was significantly associated with higher pCR. CONCLUSIONS: Adding pembrolizumab to trimodality therapy showed acceptable tolerability but did not meet the pre-specified pCR endpoint. Exploratory analyses suggested that high PD-L1 expression in the TME and/or on EVs may identify patients most likely to achieve tumor response.


Assuntos
Adenocarcinoma , Antineoplásicos Imunológicos , Adenocarcinoma/tratamento farmacológico , Anticorpos Monoclonais Humanizados , Antineoplásicos Imunológicos/efeitos adversos , Antígeno B7-H1/metabolismo , Neoplasias Esofágicas , Junção Esofagogástrica/patologia , Humanos , Terapia Neoadjuvante , Microambiente Tumoral
10.
Cancer Immunol Res ; 10(2): 162-181, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34911739

RESUMO

Cytotoxic CD8+ T cells (CTL) are a crucial component of the immune system notable for their ability to eliminate rapidly proliferating malignant cells. However, the T-cell intrinsic factors required for human CTLs to accomplish highly efficient antitumor cytotoxicity are not well defined. By evaluating human CD8+ T cells from responders versus nonresponders to treatment with immune checkpoint inhibitors, we sought to identify key factors associated with effective CTL function. Single-cell RNA-sequencing analysis of peripheral CD8+ T cells from patients treated with anti-PD-1 therapy showed that cells from nonresponders exhibited decreased expression of the cytolytic granule-associated molecule natural killer cell granule protein-7 (NKG7). Functional assays revealed that reduced NKG7 expression altered cytolytic granule number, trafficking, and calcium release, resulting in decreased CD8+ T-cell-mediated killing of tumor cells. Transfection of T cells with NKG7 mRNA was sufficient to improve the tumor-cell killing ability of human T cells isolated from nonresponders and increase their response to anti-PD-1 or anti-PD-L1 therapy in vitro. NKG7 mRNA therapy also improved the antitumor activity of murine tumor antigen-specific CD8+ T cells in an in vivo model of adoptive cell therapy. Finally, we showed that the transcription factor ETS1 played a role in regulating NKG7 expression. Together, our results identify NKG7 as a necessary component for the cytotoxic function of CD8+ T cells and establish NKG7 as a T-cell-intrinsic therapeutic target for enhancing cancer immunotherapy.See related article by Li et al., p. 154.


Assuntos
Linfócitos T CD8-Positivos , Imunoterapia , Proteínas de Membrana , Neoplasias , RNA Mensageiro , Animais , Linfócitos T CD8-Positivos/imunologia , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , RNA Mensageiro/uso terapêutico , Linfócitos T Citotóxicos
11.
Nucl Med Biol ; 100-101: 4-11, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34119742

RESUMO

INTRODUCTION: Immunotherapy targeting PD-1/PD-L1 immune checkpoint inhibition (ICI) is efficacious in various solid and hematologic malignancies. However, the response rate to PD-1/PD-L1 therapy is only 15-35%. To obtain optimal clinical response to ICI therapies, a reliable assessment of tumor PD-L1 expression is needed to select appropriate patients, and a non-invasive imaging-based assessment of PD-L1 expression is critically needed. Although radiolabeled PET probes based on PD-L1 targeted therapeutic antibodies (e.g. atezolizumab) have shown encouraging results, there is concern that residual therapeutic antibody may compete for binding with the radiotracer thereby compromising imaging studies that follow treatment. METHODS AND RESULTS: In this study, we used novel anti-PD-L1-B11 clone antibody known to bind to a different epitope of PD-L1 than the therapeutic antibodies to avoid potential saturation effects. The anti-PD-L1-B11 clone was radiolabeled with zirconium-89 and evaluated to detect PD-L1 expression in various in vitro and in vivo cancer model systems in comparison with [89Zr]Zr-DFO-NCS-atezolizumab. In vitro binding parameters of anti-PD-L1-B11 were like those of atezolizumab. [89Zr]Zr-DFO-NCS-anti-PD-L1-B11 clone showed favorable properties to [89Zr]Zr-DFO-NCS-atezolizumab in an in vivo breast cancer tumor model system with higher uptake in PD-L1 expressing tumors. CONCLUSION: Our data demonstrates that [89Zr]Zr-DFO-NCS-anti-PD-L1-B11 exhibits excellent imaging properties for the assessment PD-L1 expression. The independent binding site of anti-PD-L1-B11 relative to therapeutic anti-PD-L1 antibodies may be advantageous for anti-PD-L1 therapy monitoring.


Assuntos
Antígeno B7-H1
12.
Am J Clin Pathol ; 155(1): 69-78, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33015712

RESUMO

OBJECTIVES: Comparative assessments of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) molecular assays that have been operationalized through the US Food and Drug Administration's Emergency Use Authorization process are warranted to assess real-world performance. Characteristics such as sensitivity, specificity, and false-negative rate are important to inform clinical use. METHODS: We compared five SARS-CoV-2 assays using nasopharyngeal and nasal swab specimens submitted in transport media; we enriched this cohort for positive specimens, since we were particularly interested in the sensitivity and false-negative rate. Performance of each test was compared with a composite standard. RESULTS: The sensitivities and false-negative rates of the 239 specimens that met inclusion criteria were, respectively, as follows: Centers for Disease Control and Prevention 2019 nCoV Real-Time RT-PCR Diagnostic Panel, 100% and 0%; TIB MOLBIOL/Roche z 480 Assay, 96.5% and 3.5%; Xpert Xpress SARS-CoV-2 (Cepheid), 97.6% and 2.4%; Simplexa COVID-19 Direct Kit (DiaSorin), 88.1% and 11.9%; and ID Now COVID-19 (Abbott), 83.3% and 16.7%. CONCLUSIONS: The assays that included a nucleic acid extraction followed by reverse transcription polymerase chain reaction were more sensitive than assays that lacked a full extraction. Most false negatives were seen in patients with low viral loads, as extrapolated from crossing threshold values.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Adulto , Idoso , Teste de Ácido Nucleico para COVID-19/normas , Estudos de Coortes , Reações Falso-Negativas , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
13.
Infect Immun ; 78(11): 4958-64, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20823198

RESUMO

Enteroaggregative Escherichia coli (EAEC) is responsible for inflammatory diarrhea in diverse populations, but its mechanisms of pathogenesis have not been fully elucidated. We have used a previously characterized polarized intestinal T84 cell model to investigate the effects of infection with EAEC strain 042 on tight junction integrity. We find that infection with strain 042 induces a decrease in transepithelial electrical resistance (TER) compared to uninfected controls and to cells infected with commensal E. coli strain HS. When the infection was limited after 3 h by washing and application of gentamicin, we observed that the TER of EAEC-infected monolayers continued to decline, and they remained low even as long as 48 h after the infection. Cells infected with the afimbrial mutant strain 042aafA exhibited TER measurements similar to those seen in uninfected monolayers, implicating the aggregative adherence fimbriae II (AAF/II) as necessary for barrier dysfunction. Infection with wild-type strain 042 induced aberrant localization of the tight junction proteins claudin-1 and, to a lesser degree, occludin. EAEC-infected T84 cells exhibited irregular shapes, and some cells became elongated and/or enlarged; these effects were not observed after infection with commensal E. coli strain HS or 042aafA. The effects on tight junctions were also observed with AAF/I-producing strain JM221, and an afimbrial mutant was similarly deficient in inducing barrier dysfunction. Our results show that EAEC induces epithelial barrier dysfunction in vitro and implicates the AAF adhesins in this phenotype.


Assuntos
Células Epiteliais/patologia , Escherichia coli/patogenicidade , Junções Íntimas/patologia , Linhagem Celular , Permeabilidade da Membrana Celular , Claudina-1 , Colo/citologia , Colo/microbiologia , Impedância Elétrica , Células Epiteliais/microbiologia , Escherichia coli/genética , Escherichia coli/metabolismo , Fímbrias Bacterianas/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia Confocal , Microscopia de Fluorescência , Ocludina , Junções Íntimas/microbiologia
14.
J Immunother Cancer ; 8(2)2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817395

RESUMO

BACKGROUND: Trans-acting programmed death-ligand 1 (PD-L1) derives from malignant cells in three known forms. High levels of secreted splice variant PD-L1 (sPD-L1), ADAM10/ADAM17-shed sPD-L1, and PD-L1-positive extracellular vesicles (evPD-L1) each predict poor prognosis and limited response to PD-(L)1 checkpoint inhibitors in cancer. To our knowledge, no clinical intervention has reduced any of these circulating forms of extracellular PD-L1. Here, we explore therapeutic plasma exchange (TPE) as a treatment to reduce circulating extracellular PD-L1. RESULTS: In patients with melanoma, sPD-L1 levels above 0.277 ng/mL predicted inferior overall survival. In patients undergoing TPE for non-malignant indications, each TPE session removed a mean 70.8% sPD-L1 and 73.1% evPD-L1 detectable in plasma. TPE also reduced total and ADAM10-positive extracellular vesicles. CONCLUSION: Here, we report the first known clinical intervention to remove either sPD-L1 or evPD-L1 from plasma in vivo. TPE reduces plasma sPD-L1 and evPD-L1 in vivo and may have a role in treatment with immunotherapy. TPE may also prove useful in patients with other extracellular vesicle-related conditions.


Assuntos
Antígeno B7-H1/imunologia , Vesículas Extracelulares/imunologia , Imunoterapia/métodos , Troca Plasmática/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Infect Immun ; 77(6): 2465-73, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19349428

RESUMO

Enteroaggregative Escherichia coli (EAEC) is increasingly being recognized as a cause of diarrheal disease in diverse populations. No small animal model is currently available to study this pathogen. We report here that conventional mice orally inoculated with prototype EAEC strain 042 generally became colonized, though the abundance of organisms cultured from their stool varied substantially among individual animals. In contrast, mice whose water contained 5 g/liter streptomycin consistently became colonized at high levels (ca. 10(8) CFU/g of stool). Neither conventional nor streptomycin-treated mice developed clinical signs or histopathologic abnormalities. Using specific mutants in competition with the wild-type strain, we evaluated the contribution of several putative EAEC virulence factors to colonization of streptomycin-treated mice. Our data suggest that the dispersin surface protein and Pic, a serine protease autotransporter secreted by EAEC and Shigella flexneri, promote colonization of the mouse. In contrast, we found no role for the aggregative adherence fimbriae, the transcriptional activator AggR, or the surface factor termed Air (enteroaggregative immunoglobulin repeat protein). To study Pic further, we constructed a single nucleotide mutation in strain 042 which altered only the Pic catalytic serine (strain 042PicS258A). Fractionation of the tissue at 24 h and 3 days demonstrated an approximate 3-log(10) difference between 042 and 042PicS258A in the lumen and mucus layer and adherent to tissue. Strains 042 and 042PicS258A adhered similarly to mouse tissue ex vivo. While no growth differences were observed in a continuous-flow anaerobic intestinal simulator system, the wild-type strain exhibited a growth advantage over 042PicS258A in a culture of cecal mucus and in cecal contents in vitro; this difference was manifest only after 6 h of growth. Moreover, enhanced growth of the wild type was observed in comparison with that of the mutant in minimal medium containing mucin but not in the absence of mucin. The data suggest a novel metabolic role for the Pic mucinase in EAEC colonization.


Assuntos
Proteínas de Escherichia coli/fisiologia , Escherichia coli/enzimologia , Escherichia coli/crescimento & desenvolvimento , Mucinas/metabolismo , Polissacarídeo-Liases/metabolismo , Serina Endopeptidases/fisiologia , Fatores de Virulência/fisiologia , Substituição de Aminoácidos/genética , Animais , Domínio Catalítico , Ceco/microbiologia , Criança , Contagem de Colônia Microbiana , Escherichia coli/isolamento & purificação , Proteínas de Escherichia coli/genética , Fezes/microbiologia , Feminino , Deleção de Genes , Humanos , Mucosa Intestinal/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese Sítio-Dirigida , Polissacarídeo-Liases/genética , Serina Endopeptidases/genética , Shigella flexneri/genética , Virulência , Fatores de Virulência/genética
16.
Laryngoscope ; 129(11): 2534-2536, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30912581

RESUMO

Chronic laryngitis commonly presents with dysphonia, and infectious causes include tuberculosis and endemic mycoses. We present a 58-year-old female with laryngitis for 5 years, fevers, chills, fatigue, malaise, myalgias, anterior neck pain, and night sweats after multicontinent exposure. Bronchoscopy cultures were negative. Bilateral microflap excision of vocal fold lesions demonstrated thickened epithelium and a deep vocal fold mass. Biopsy showed necrotizing granulomatous inflammation with acid-fast bacilli. Mycobacterium kansasii was identified. Treatment led to improvement in dysphonia, systemic symptoms, and vocal fold irritation. To our knowledge, this is the first case of isolated nontuberculous mycobacterial vocal fold infection. Laryngoscope, 129:2534-2536, 2019.


Assuntos
Laringite/microbiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium kansasii , Doença Relacionada a Viagens , Doença Crônica , Feminino , Humanos , Pessoa de Meia-Idade
18.
Sci Rep ; 9(1): 10677, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337865

RESUMO

Tumor expression of immune co-inhibitory ligands, such as PD-L1 and Galectin-9, have potential prognostic value in Hepatocellular Carcinoma (HCC). Circulating levels of these molecules, however, have hardly been studied. This study aims to assess the prognostic significance of circulating PD-L1 and circulating Galectin-9 in patients with resected HCC, and to compare their prognostic significance to the intra-tumoral expression of these same molecules. Archived tissues and stored peripheral blood samples from 81 patients who underwent HCC resection or liver transplantation, with curative intent, were used. Immunohistochemistry was performed to determine intra-tumoral expression of PD-L1 and Galectin-9, while ELISA was used to quantify their respective circulating levels. High circulating PD-L1 (HR 0.12, 95%CI 0.16-0.86, p = 0.011) and high circulating Galectin-9 (HR 0.11, 95%CI 0.15-0.85, p = 0.010) levels were both associated with improved HCC-specific survival. Surprisingly, there was no correlation between circulating levels of PD-L1 and Galectin-9 and their intra-tumoral expression levels. In fact, circulating levels of PD-L1 and Galectin-9 were predictive of HCC-specific survival independently of intra-tumoral levels and baseline clinicopathologic characteristics. Combined analysis of circulating levels and intra-tumoral expression of PD-L1 (HR 0.33, 95%CI 0.16-0.68, p = 0.002) and Galectin-9 (HR 0.27, 95%CI 0.13-0.57, p = 0.001) resulted in more confident prediction of survival. In conclusion, circulating PD-L1 and Galectin-9 levels prognostically differentiate resected HCC patients, independently of their intra-tumoral expression. Combining circulating and intra-tumoral expression levels of PD-L1 or Galectin-9 further improves the prognostic values of these immune biomarkers.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma Hepatocelular/mortalidade , Galectinas/metabolismo , Neoplasias Hepáticas/mortalidade , Adulto , Idoso , Antígeno B7-H1/sangue , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/cirurgia , Feminino , Galectinas/sangue , Hepatectomia , Humanos , Fígado/metabolismo , Fígado/cirurgia , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
19.
J Clin Microbiol ; 46(6): 1978-84, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18353931

RESUMO

Quantitative real-time PCR (qPCR) may improve the detection of fungal pathogens. Extraction of DNA from fungal pathogens is fundamental to optimization of qPCR; however, the loss of fungal DNA during the extraction process is a major limitation to molecular diagnostic tools for pathogenic fungi. We therefore studied representative automated and manual extraction methods for Aspergillus fumigatus and Rhizopus oryzae. Both were analyzed by qPCR for their ability to extract DNA from propagules and germinated hyphal elements (GHE). The limit of detection of A. fumigatus and R. oryzae GHE in bronchoalveolar lavage (BAL) fluid with either extraction method was 1 GHE/ml. Both methods efficiently extracted DNA from A. fumigatus, with a limit of detection of 1 x 10(2) conidia. Extraction of R. oryzae by the manual method resulted in a limit of detection of 1 x 10(3) sporangiospores. However, extraction with the automated method resulted in a limit of detection of 1 x 10(1) sporangiospores. The amount of time to process 24 samples by the automated method was 2.5 h prior to transferring for automation, 1.3 h of automation, and 10 min postautomation, resulting in a total time of 4 h. The total time required for the manual method was 5.25 h. The automated and manual methods were similar in sensitivity for DNA extraction from A. fumigatus conidia and GHE. For R. oryzae, the automated method was more sensitive for DNA extraction of sporangiospores, while the manual method was more sensitive for GHE in BAL fluid.


Assuntos
Aspergillus fumigatus/isolamento & purificação , Líquido da Lavagem Broncoalveolar/microbiologia , DNA Fúngico/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Rhizopus/isolamento & purificação , Animais , Aspergilose , Aspergillus fumigatus/genética , Aspergillus fumigatus/crescimento & desenvolvimento , Automação , DNA Fúngico/análise , Humanos , Hifas/genética , Coelhos , Rhizopus/genética , Rhizopus/crescimento & desenvolvimento , Esporos Fúngicos/genética
20.
J Clin Microbiol ; 46(11): 3690-702, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18845827

RESUMO

We developed two real-time quantitative PCR (qPCR) assays, targeting the 28S rRNA gene, for the diagnosis of zygomycosis caused by the most common, clinically significant Zygomycetes. The amplicons of the first qPCR assay (qPCR-1) from Rhizopus, Mucor, and Rhizomucor species were distinguished through melt curve analysis. The second qPCR assay (qPCR-2) detected Cunninghamella species using a different primer/probe set. For both assays, the analytic sensitivity for the detection of hyphal elements from germinating sporangiospores in bronchoalveolar lavage (BAL) fluid and lung tissue homogenates from rabbits was 1 to 10 sporangiospores/ml. Four unique and clinically applicable models of invasive pulmonary zygomycosis served as surrogates of human infections, facilitating the validation of these assays for potential diagnostic utility. For qPCR-1, 5 of 98 infarcted lung specimens were positive by qPCR and negative by quantitative culture (qCx). None were qCx positive only. Among 23 BAL fluid samples, all were positive by qPCR, while 22 were positive by qCx. qPCR-1 detected Rhizopus and Mucor DNA in 20 (39%) of 51 serial plasma samples as early as day 1 postinoculation. Similar properties were observed for qPCR-2, which showed greater sensitivity than qCx for BAL fluid (100% versus 67%; P = 0.04; n = 15). The assay detected Cunninghamella DNA in 18 (58%) of 31 serial plasma samples as early as day 1 postinoculation. These qPCR assays are sensitive and specific for the detection of Rhizopus, Mucor, Rhizomucor, and Cunninghamella species and can be used for the study and detection of infections caused by these life-threatening pathogens.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Fungos/classificação , Fungos/isolamento & purificação , Pneumopatias Fúngicas/diagnóstico , Pulmão/microbiologia , Plasma/microbiologia , Reação em Cadeia da Polimerase/métodos , Zigomicose/diagnóstico , Animais , Biomarcadores , Feminino , Fungos/genética , RNA Fúngico/genética , RNA Ribossômico 28S/genética , Coelhos , Sensibilidade e Especificidade
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