31 results on '"Javier Mestas"'
Search Results
2. Implementation of a Streamlined SARS-CoV-2 Whole-Genome Sequencing Assay for Expeditious Surveillance during the Emergence of the Omicron Variant
- Author
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John A. Fissel, Javier Mestas, Pei Ying Chen, Jessica Flores-Vazquez, Thao T. Truong, Moiz Bootwalla, Dennis T. Maglinte, Xiaowu Gai, and Jennifer Dien Bard
- Subjects
Microbiology (medical) ,Whole Genome Sequencing ,SARS-CoV-2 ,Mutation ,COVID-19 ,Humans - Published
- 2022
3. A 5-year study of the performance of the Verigene Gram-positive blood culture panel in a pediatric hospital
- Author
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Claudia M. Polanco, Javier Mestas, Jennifer Dien Bard, and Chairut Vareechon
- Subjects
0301 basic medicine ,Microbiology (medical) ,medicine.medical_specialty ,Gram positive blood culture panel ,Concordance ,030106 microbiology ,medicine.disease_cause ,Microbiology ,03 medical and health sciences ,0302 clinical medicine ,Medical microbiology ,medicine ,Blood culture ,030212 general & internal medicine ,medicine.diagnostic_test ,biology ,business.industry ,SCCmec ,General Medicine ,biochemical phenomena, metabolism, and nutrition ,bacterial infections and mycoses ,Antimicrobial ,biology.organism_classification ,Infectious Diseases ,Staphylococcus aureus ,business ,Enterococcus faecium - Abstract
High accuracy of direct from positive blood culture molecular panels is imperative, particularly for the detection of resistance determinants as it allows for antimicrobial optimization prior to conventional susceptibility testing. In this study, we provide extensive data since implementation of the Verigene Gram-positive blood culture panel (BC-GP) in 2013. Within 5 years, 1636 blood culture bottles positive for a Gram-positive organism were tested on the BC-GP panel. The BC-GP panel identified 1520 Gram-positive organisms in 1636 (92.9%) blood cultures tested. For positive blood cultures, we observed 96.4% (806/834) concordance to the species level. Compared with conventional antimicrobial susceptibility testing, the positive percent agreement (PPA) of methicillin-resistant SA (MRSA) (50) and methicillin-resistant SE (MRSE) (365) was 100%. The mecA gene was detected in two methicillin-susceptible Staphylococcus aureus (MSSA) and one methicillin-susceptible S. epidermidis (MSSE) with a negative percent agreement (NPA) of 99.1% (221/223) and 99.2% (120/121), respectively. The PPA and NPA for vancomycin-resistant Enterococcus faecium (VRE) was 100%. The BC-GP panel demonstrated excellent performance and clinicians can confidently de-escalate antimicrobial therapy in the absence of mecA and vanA/B gene.
- Published
- 2018
4. 322. Evaluation of the BioFire® Bone and Joint Infection (BJI) Panel for the Detection of Microorganisms and Antimicrobial Resistance Genes in Synovial Fluid Specimens
- Author
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Corrin Graue, Bryan H Schmitt, Amy Waggoner, Frederic Laurent, Lelia Abad, Thomas Bauer, Irving Mazariegos, Joan-Miquel Balada-Llasat, Jarid Horn, Donna Wolk, Alexa Jefferis, Mirjam Hermans, Irma Verhoofstad, Susan Butler-Wu, Minette Umali-Wilcox, Caitlin N Murphy, Barbara J Cabrera, Jaime Esteban, Alicia Macias-Valcayo, David Craft, Benjamin von Bredow, Amy Leber, Kathy Everhart, Jennifer Dien Bard, Javier Mestas, Judy Daly, Rebecca Barr, Bart Kensinger, Benedicte Pons, and Corinne Jay
- Subjects
business.industry ,Microorganism ,medicine.medical_treatment ,Arthrocentesis ,Knee Joint ,Pathogenicity ,Microbiology ,AcademicSubjects/MED00290 ,Infectious Diseases ,Oncology ,Bsnd gene ,Poster Abstracts ,Antimicrobial resistance genes ,Synovial fluid ,Medicine ,Anaerobic bacteria ,business - Abstract
Background Bone and Joint Infections (BJIs) present with non-specific symptoms that may include pain, swelling, and fever and are associated with high morbidity and significant risk of mortality. BJIs can be caused by a variety of bacteria and fungi, including anaerobes and microorganisms that can be challenging to culture or identify by traditional microbiological methods. Clinicians primarily rely on culture to identify the pathogen(s) responsible for infection. The BioFire® Bone and Joint Infection (BJI) Panel (BioFire Diagnostics, Salt Lake City, UT) is designed to detect 15 gram-positive bacteria (including seven anaerobes), 14 gram-negative bacteria (including one anaerobe), two yeast, and eight antimicrobial resistance (AMR) genes from synovial fluid specimens in about an hour. The objective of this study was to evaluate the performance of an Investigational Use Only (IUO) version of the BioFire BJI Panel compared to various reference methods. Methods Remnant synovial fluid specimens, which were collected for routine clinical care at 13 study sites in the US and Europe, underwent testing using an IUO version of the BioFire BJI Panel. Performance of this test was determined by comparison to Standard of Care (SoC) consisting of bacterial culture performed at each study site according to their routine procedures. Results A total of 1544 synovial fluid specimens were collected and tested with the BioFire BJI Panel. The majority of specimens were from knee joints (77.9%) and arthrocentesis (79.4%) was the most common collection method. Compared to SoC culture, overall sensitivity was 90.2% and specificity was 99.8%. The BioFire BJI Panel yielded a total of 268 Detected results, whereas SoC yielded a total of 215 positive results for on-panel analytes. Conclusion The BioFire BJI Panel is a sensitive, specific, and robust test for rapid detection of a wide range of analytes in synovial fluid specimens. The number of microorganisms and resistance genes included in the BioFire BJI Panel, together with a reduced time-to-result and increased diagnostic yield compared to culture, is expected to aid in the timely diagnosis and appropriate management of BJIs. Disclosures Benjamin von Bredow, PhD, BioFire (Grant/Research Support) Jennifer Dien Bard, PhD, BioFire Diagnostic (Consultant, Scientific Research Study Investigator) Bart Kensinger, PhD, BioFire Diagnostics (Employee) Benedicte Pons, PhD, bioMerieux SA (Employee) Corinne Jay, PhD, bioMerieux SA (Employee)
- Published
- 2020
5. Direct Identification of Aerobic Bacteria by Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry Is Accurate and Robust
- Author
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Jennifer Dien Bard, Teephany Quias, and Javier Mestas
- Subjects
0301 basic medicine ,Microbiology (medical) ,Identification methods ,Chromatography ,Aerobic bacteria ,030106 microbiology ,Biochemistry (medical) ,Clinical Biochemistry ,Extraction (chemistry) ,Public Health, Environmental and Occupational Health ,Analytical chemistry ,Matrix assisted laser desorption ionization time of flight ,Hematology ,Biology ,biology.organism_classification ,Mass spectrometry ,03 medical and health sciences ,Medical Laboratory Technology ,Matrix-assisted laser desorption/ionization ,Immunology and Allergy ,Identification (biology) ,Bacteria - Abstract
Background Bacterial identification in the clinical laboratory can be laborious and expensive. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid and cost-effective diagnostic tool for the identification of organisms routinely found in the microbiology laboratory. The objective of this study was to demonstrate that identification of aerobic Gram-positive and Gram-negative organisms could be performed accurately and efficiently by MALDI-TOF MS and the Bruker Biotyper system without the use of time-consuming extraction methodologies. Methods Isolates previously recovered by routine culture and workup from clinical specimens were cultured to appropriate media, identified directly by MALDI-TOF MS, and compared to results from various biochemical identification methods. Results Using the direct-smear method, 99.5% and 98.0% of aerobic Gram-negative and Gram-positive bacteria, respectively, were identified to the genus level. At a score of ≥1.9, 97.6% Gram-negative organisms and 94.6% Gram-positive organisms were correctly identified to the species level by direct-smear method. Only 1.1% of isolates required further reflex to direct-plate extraction. The direct-smear method proved to be robust, as various growth temperatures, media, culture age, and different operators had no notable impact on the bacterial identification rate. Conclusion The direct-smear method is an accurate and time-saving method for routine species-level bacterial identification.
- Published
- 2015
6. A 5-year study of the performance of the Verigene Gram-positive blood culture panel in a pediatric hospital
- Author
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Chairut, Vareechon, Javier, Mestas, Claudia M, Polanco, and Jennifer, Dien Bard
- Subjects
Bacteriological Techniques ,Cross Infection ,Molecular Diagnostic Techniques ,Blood Culture ,Genes, Bacterial ,Drug Resistance, Bacterial ,Humans ,Bacteremia ,Gram-Positive Bacteria ,Hospitals, Pediatric ,Gram-Positive Bacterial Infections ,Retrospective Studies - Abstract
High accuracy of direct from positive blood culture molecular panels is imperative, particularly for the detection of resistance determinants as it allows for antimicrobial optimization prior to conventional susceptibility testing. In this study, we provide extensive data since implementation of the Verigene Gram-positive blood culture panel (BC-GP) in 2013. Within 5 years, 1636 blood culture bottles positive for a Gram-positive organism were tested on the BC-GP panel. The BC-GP panel identified 1520 Gram-positive organisms in 1636 (92.9%) blood cultures tested. For positive blood cultures, we observed 96.4% (806/834) concordance to the species level. Compared with conventional antimicrobial susceptibility testing, the positive percent agreement (PPA) of methicillin-resistant SA (MRSA) (50) and methicillin-resistant SE (MRSE) (365) was 100%. The mecA gene was detected in two methicillin-susceptible Staphylococcus aureus (MSSA) and one methicillin-susceptible S. epidermidis (MSSE) with a negative percent agreement (NPA) of 99.1% (221/223) and 99.2% (120/121), respectively. The PPA and NPA for vancomycin-resistant Enterococcus faecium (VRE) was 100%. The BC-GP panel demonstrated excellent performance and clinicians can confidently de-escalate antimicrobial therapy in the absence of mecA and vanA/B gene.
- Published
- 2018
7. Molecular Testing for Detection of Groups A, C, and G β-Hemolytic Streptococci in Pharyngeal Samples from Children
- Author
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Jennifer Dien Bard, Javier Mestas, and Tam T. Van
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Streptococcus ,business.industry ,030106 microbiology ,General Medicine ,Gold standard (test) ,medicine.disease_cause ,Group A ,Gastroenterology ,Patient care ,Pharyngitis ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,Internal medicine ,medicine ,030212 general & internal medicine ,medicine.symptom ,business ,Routine care - Abstract
Background Group A Streptococcus (GAS) and large colony-forming group C (GCS) and G (GGS) β-hemolytic streptococci are important causes of acute pharyngitis in children and adults. Rapid and accurate diagnosis of streptococcal pharyngitis can improve patient care and potentially reduce transmission. In this study, we evaluated the performance of the Lyra Direct Strep (LDS) assay for detection of GAS and GCS/GGS compared with traditional culture methods. Methods Pharyngeal samples obtained from 278 children presenting to the emergency department with initial negative GAS rapid antigen detection test (RADT) were used. All samples were cultured as part of routine care and tested in batches using the LDS assay. Results Of 278 pharyngeal samples with negative GAS RADT, 37 (13.3%) and 63 (22.7%) patients were positive for GAS by culture and LDS assay, respectively. Four (1.4%) patients were positive for GCS or GGS by culture or LDS assay. The LDS assay demonstrated sensitivity and specificity of 97.6% and 89.0%, respectively, compared with culture as the gold standard. Repeat culture and an alternate PCR showed that 85.7% (24 of 28) of discrepant samples agreed with findings of the LDS assay. Since implementation, the LDS assay shows a positivity rate of 21.0% (281 of 1340) compared with 11.7% (246 of 2110) by culture in the previous year. Conclusions We successfully implemented the LDS assay at our institution and have observed a significant increase in the positivity rate of GAS compared with culture. The LDS assay alone allowed for the elimination of β-streptococci screening by culture at our institution.
- Published
- 2018
8. One Year in the Life of a Rapid Syndromic Panel for Meningitis/Encephalitis: a Pediatric Tertiary Care Facility's Experience
- Author
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Javier Mestas, Maryann Lustestica, Jennifer Dien Bard, Samia N. Naccache, and Margil Fahit
- Subjects
0301 basic medicine ,Microbiology (medical) ,Pediatrics ,medicine.medical_specialty ,030106 microbiology ,Rapid detection ,Tertiary care ,03 medical and health sciences ,0302 clinical medicine ,Meningitis/encephalitis ,medicine ,Humans ,Meningitis ,030212 general & internal medicine ,Child ,Cerebrospinal Fluid ,Retrospective Studies ,Bacteria ,business.industry ,Tertiary Healthcare ,Reproducibility of Results ,Bacteriology ,medicine.disease ,Los Angeles ,Molecular Diagnostic Techniques ,Viruses ,Encephalitis ,Reagent Kits, Diagnostic ,business ,Program Evaluation - Abstract
Early establishment of infectious processes allows for expedited clinical management of meningitis and encephalitis. The FilmArray meningitis/encephalitis (FA-M/E) panel provides rapid detection of potential pathogens associated with encephalitis/meningitis in both immunocompetent and compromised patients. Here, we conducted a 1-year review of the performance of the FA-M/E panel at a tertiary care children's hospital. Two hundred sixty-five samples from 251 patients were tested. We found 87.25% (219/251) were negative, 9.96% (25/251) were positive for viral analytes, and 3.19% (8/251) were positive for bacterial analytes. When possible, positive results were confirmed by alternate testing; 4/6 available bacterial positives and 17/20 available viral positives were confirmed by retrospective culture or molecular testing.
- Published
- 2017
9. 2290. Identification of Pathogens in Synovial Fluid Samples With an Automated Multiplexed Molecular Detection System
- Author
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Kevin M. Bourzac, Helene Savelli, Joan-Miquel Balada-Llasat, Bart J. Kensinger, Thibault Martin, Jaime Esteban, Bryan H. Schmitt, Susan M. Butler-Wu, Corinne Jay, Stéphane Magro, Javier Mestas, Isabelle Sothier, Jarid Horn, Lélia Abad, Amy Leber, Frédéric Laurent, Amy Waggoner, Benedicte Pons, Jennifer Bien-Bard, Cristina Costales, Kathy Everhart, Llanos Salar-Vidal, Samuel Collier, Caitlin N. Murphy, Amanda T. Harrington, Pharm D, and Arryn Craney
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Chromatography ,Standard of care ,business.industry ,Joint infections ,Pathogenic organism ,Abstracts ,Infectious Diseases ,fluids and secretions ,Oncology ,B. Poster Abstracts ,Medicine ,Molecular diagnostic techniques ,Synovial fluid ,Identification (biology) ,business - Abstract
Background Bone and Joint Infections (BJI) have high morbidity and are difficult to treat infections. Culture-based diagnosis is limited in its ability to recover fastidious bacteria and because several organisms can be involved; culture times of up to two weeks may be necessary for certain bacteria. The sensitivity of culture is also negatively impacted by antibiotics received before surgery. Alternatively, molecular methods offer a promising improvement for the diagnosis of BJI. The goal of this study was to evaluate a development version of Biofire® Bone and Joint Infection (BJI) Panel (bioMerieux SA, BioFire Diagnostics, LLC) using synovial fluid samples. Methods 121 synovial fluid specimens were collected from patients with suspected bone and joint infection in a pilot evaluation. All specimens were collected and tested in culture by the sites using their standard of care practices; in parallel, a leftover volume of 200 µL was tested on the BJI panel. BJI panel results were then compared with culture and discordant results were investigated using a comparator assay (PCR/sequencing). Results 49 synovial fluid specimens (40%) were positive by culture vs. 72 with the BJI panel (59%). Of the 97 positive detections by the BJI panel, 58 were concordant with culture; the 39 additional organism detections were in majority confirmed by PCR/sequencing. Lastly, two false negative results corresponding to the same sample are under investigation. Conclusion The BJI Panel was able to identify most of the pathogens detected by culture. The majority of additional detections observed were confirmed by PCR/sequencing. While sites are currently enrolling more synovial fluids samples, these preliminary data suggest that a multiplexed molecular test may be more sensitive than culture to detect pathogens in synovial fluid specimens. The data presented in this abstract have not been reviewed by FDA or other regulatory agencies for In Vitro Diagnostic use. Disclosures B. Pons, bioMerieux: Employee, Salary. C. Jay, bioMerieux: Employee, Salary. T. Martin, bioMerieux: Employee, Salary. I. Sothier, bioMerieux: Employee, Salary. H. Savelli, bioMerieux: Employee, Salary. B. Kensinger, bioFire a bioMerieux company: Employee, Salary. F. Laurent, BioFire (bioMerieux company): Investigator, Research support. L. Abad, BioFire (bioMerieux company): Investigator, Research support. C. Murphy, BioFire (bioMerieux company): Investigator, Research support. A. Craney, BioFire (bioMerieux company): Investigator, Research support. B. Schmitt, BioFire (bioMerieux company): Investigator, Research support. A. Waggoner, BioFire (bioMerieux company): Investigator, Research support. S. Butler-Wu, BioFire (bioMerieux): Investigator, Research support. C. Costales, BioFire (bioMerieux company): Investigator, Research support. J. Bien-Bard, BioFire (bioMerieux): Investigator, Research support. J. Mestas, BioFire (bioMerieux): Investigator, Research support. J. Esteban, BioFire (bioMerieux): Investigator, Research support. L. Salar-Vidal, BioFire (BioMerieux company)): Investigator, Research support. A. Harrington, BioFire (bioMerieux company): Investigator, Research support. S. Collier, BioFire (BioMerieux Company): Investigator, Research support. A. Leber, BioFire (bioMerieux company): Investigator, Research support. K. Everhart, BioFire (bioMerieux company): Investigator, Research support. J. M. Balada-Llasat, BioFire (bioMerieux company): Investigator, Research support. J. Horn, BioFire (bioMerieux company): Investigator, Research support. S. Magro, bioMerieux: Employee, Salary. K. Bourzac, BioFire a bioMerieux company: Employee, Salary.
- Published
- 2018
10. Performance of the Verigene Gram-Positive Blood Culture Assay for Direct Detection of Gram-Positive Organisms and Resistance Markers in a Pediatric Hospital
- Author
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Susanna Felsenstein, Claudia M. Polanco, Javier Mestas, and Jennifer Dien Bard
- Subjects
Male ,Microbiology (medical) ,Pathology ,medicine.medical_specialty ,Adolescent ,Gram-positive bacteria ,Concordance ,Bacteremia ,Gram-Positive Bacteria ,Microbiology ,Pediatric hospital ,Humans ,Medicine ,Blood culture ,Child ,Gram-Positive Bacterial Infections ,Gram-positive bacterial infections ,Gram ,Bacteriological Techniques ,medicine.diagnostic_test ,biology ,business.industry ,Infant ,Bacteriology ,Hospitals, Pediatric ,medicine.disease ,biology.organism_classification ,Anti-Bacterial Agents ,Molecular Diagnostic Techniques ,Child, Preschool ,Positive blood culture ,Female ,business - Abstract
The performance characteristics of the Verigene Gram-positive blood culture (BC-GP) assay were evaluated in pediatric patients. Concordance of the BC-GP assay was 95.8%, with significant decreases in turnaround time for identification and resistance detection. BC-GP is highly accurate and can be integrated into the routine workflow of the microbiology laboratory.
- Published
- 2014
11. Multicenter Evaluation of BioFire FilmArray Meningitis/Encephalitis Panel for Detection of Bacteria, Viruses, and Yeast in Cerebrospinal Fluid Specimens
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Joan-Miquel Balada-Llasat, J. Kristie Johnson, Paul R. Lephart, Amy Leber, Jo Anne Miller, Paul C. Schreckenberger, Sharon L. Reed, Sarah Holt, Jennifer Dien Bard, Karen C. Carroll, Judy A. Daly, Sharon DesJarlais, Kimberle C. Chapin, Nicole L. Soliven, Jillian Cullison, Tori Enomoto, Matthew J. Bankowski, Kevin M. Bourzac, Andrew C. Hemmert, Lindsay LeBlanc, Javier Mestas, Kathy Everhart, Hossein Salimnia, and Forbes, BA
- Subjects
0301 basic medicine ,Male ,Time Factors ,medicine.disease_cause ,Medical and Health Sciences ,law.invention ,0302 clinical medicine ,Central Nervous System Fungal Infections ,law ,80 and over ,Prospective Studies ,Pathology, Molecular ,Child ,Cerebrospinal Fluid ,biology ,Neisseria meningitidis ,Bacterial Infections ,Middle Aged ,Biological Sciences ,Gram staining ,Infectious Diseases ,Molecular Diagnostic Techniques ,Virus Diseases ,Viruses ,Encephalitis ,Female ,Infection ,Meningitis ,Biotechnology ,Microbiology (medical) ,Adult ,Adolescent ,030106 microbiology ,and over ,Sensitivity and Specificity ,Microbiology ,03 medical and health sciences ,Young Adult ,Clinical Research ,030225 pediatrics ,Streptococcus pneumoniae ,medicine ,Humans ,Preschool ,Aged ,Cryptococcus neoformans ,Bacteria ,Agricultural and Veterinary Sciences ,business.industry ,Fungi ,Infant ,Bacteriology ,biology.organism_classification ,medicine.disease ,Newborn ,Virology ,Emerging Infectious Diseases ,Streptococcus agalactiae ,Enterovirus ,business - Abstract
Rapid diagnosis and treatment of infectious meningitis and encephalitis are critical to minimize morbidity and mortality. Comprehensive testing of cerebrospinal fluid (CSF) often includes Gram stain, culture, antigen detection, and molecular methods, paired with chemical and cellular analyses. These methods may lack sensitivity or specificity, can take several days, and require significant volume for complete analysis. The FilmArray Meningitis/Encephalitis (ME) Panel is a multiplexed in vitro diagnostic test for the simultaneous, rapid (∼1-h) detection of 14 pathogens directly from CSF specimens: Escherichia coli K1, Haemophilus influenzae , Listeria monocytogenes , Neisseria meningitidis , Streptococcus pneumoniae , Streptococcus agalactiae , cytomegalovirus, enterovirus, herpes simplex virus 1 and 2, human herpesvirus 6, human parechovirus, varicella-zoster virus, and Cryptococcus neoformans / Cryptococcus gattii . We describe a multicenter evaluation of 1,560 prospectively collected CSF specimens with performance compared to culture (bacterial analytes) and PCR (all other analytes). The FilmArray ME Panel demonstrated a sensitivity or positive percentage of agreement of 100% for 9 of 14 analytes. Enterovirus and human herpesvirus type 6 had agreements of 95.7% and 85.7%, and L. monocytogenes and N. meningitidis were not observed in the study. For S. agalactiae , there was a single false-positive and false-negative result each, for a sensitivity and specificity of 0 and 99.9%, respectively. The specificity or negative percentage of agreement was 99.2% or greater for all other analytes. The FilmArray ME Panel is a sensitive and specific test to aid in diagnosis of ME. With use of this comprehensive and rapid test, improved patient outcomes and antimicrobial stewardship are anticipated.
- Published
- 2016
12. Application of Laser Light Scattering Technology in Rapid Diagnosis of Urinary Tract Infections and Antimicrobial Susceptibility Testing in a Tertiary Children’s Hospital
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Jennifer Dien Bard, Samia N. Naccache, Javier Mestas, Andrew Tomaras, and Tam T. Van
- Subjects
0301 basic medicine ,Pediatrics ,medicine.medical_specialty ,business.industry ,Urinary system ,030106 microbiology ,Antimicrobial susceptibility ,Poster Abstract ,Dermatology ,Laser light scattering ,03 medical and health sciences ,Abstracts ,Infectious Diseases ,Oncology ,medicine ,business - Abstract
Background Timely and accurate microbiology testing is crucial in the diagnosis and management of urinary tract infections (UTIs). The ability to rapidly screen for potential UTIs can lead to early rule out and judicious use of antimicrobial therapy. This study examines the application of laser scattering for bacterial detection and antimicrobial susceptibility testing (AST) directly from urine. Methods Residual urine samples collected for routine culture were tested using the BacterioScan™ 216Dx™ UTI System and 216R AST System. Continuous collection of light refraction patterns generated growth curve that was used to determine whether the sample was likely positive or negative for bacteria. Further curve analysis ruled out mixed flora at lower concentrations, and “qualified” samples were identified directly on MALDI-TOF MS. AST for ampicillin, cefazolin, ceftriaxone and ciprofloxacin was performed concurrently on the instrument. Samples were incubated for up to 16 hours with results available as early as 2 hours. Results 210 urine samples were tested. After 3 hours of incubation on the BacterioScan, 70 (33.3%) and 140 (67.7%) urine samples were reported as positive and negative for bacterial growth, respectively. 136/140 (97.1%) of the negative samples were either no growth (67.6%) or insignificant (32.4%) growth by culture. The remaining 4 (2.9%) were catheter (3) or surgical (1) samples that grew
- Published
- 2017
13. Monocyte-Endothelial Cell Interactions in the Development of Atherosclerosis
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Javier Mestas and Klaus Ley
- Subjects
Integrins ,Endothelium ,Vascular Cell Adhesion Molecule-1 ,Inflammation ,Monocytes ,Article ,E-selectin ,medicine ,Humans ,Cell adhesion ,Membrane Glycoproteins ,biology ,Cell adhesion molecule ,Chemistry ,Monocyte ,Endothelial Cells ,Atherosclerosis ,Intercellular adhesion molecule ,Cell biology ,Lipoproteins, LDL ,Endothelial stem cell ,P-Selectin ,medicine.anatomical_structure ,biology.protein ,Endothelium, Vascular ,Chemokines ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,Cell Adhesion Molecules - Abstract
The activation of endothelial cells at atherosclerotic lesion-prone sites in the arterial tree results in the up-regulation of cell adhesion molecules and chemokines, which mediate the recruitment of circulating monocytes. Accumulation of monocytes and monocyte-derived phagocytes in the wall of large arteries leads to chronic inflammation and the development and progression of atherosclerosis. This review discusses the nature of these molecules and the mechanisms involved in the early steps of monocyte recruitment into atherosclerotic lesion sites within the vessel wall.
- Published
- 2008
14. The Role of CXCR2/CXCR2 Ligand Biological Axis in Renal Cell Carcinoma
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Allan J. Pantuck, Marie D. Burdick, Javier Mestas, Robert A. Figlin, Karen L. Reckamp, and Robert M. Strieter
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musculoskeletal diseases ,Pathology ,medicine.medical_specialty ,Angiogenesis ,Immunology ,Biology ,Ligands ,medicine.disease_cause ,Receptors, Interleukin-8B ,Metastasis ,Neovascularization ,Mice ,Renal cell carcinoma ,Tumor Cells, Cultured ,medicine ,Animals ,Humans ,Immunology and Allergy ,CXC chemokine receptors ,Neoplasm Metastasis ,Carcinoma, Renal Cell ,Mice, Knockout ,Mice, Inbred BALB C ,Neovascularization, Pathologic ,hemic and immune systems ,respiratory system ,Flow Cytometry ,medicine.disease ,biological factors ,respiratory tract diseases ,CXCL1 ,Disease Models, Animal ,Kinetics ,CXCL5 ,medicine.symptom ,Carcinogenesis - Abstract
Renal cell carcinoma (RCC) accounts for 3% of new cancer incidence and mortality in the United States. Studies in RCC have predominantly focused on VEGF in promoting tumor-associated angiogenesis. However, other angiogenic factors may contribute to the overall angiogenic milieu of RCC. We hypothesized that the CXCR2/CXCR2 ligand biological axis represents a mechanism by which RCC cells promote angiogenesis and facilitate tumor growth and metastasis. Therefore, we first examined tumor biopsies and plasma of patients with metastatic RCC for levels of CXCR2 ligands, and RCC tumor biopsies for the expression of CXCR2. The proangiogenic CXCR2 ligands CXCL1, CXCL3, CXCL5, and CXCL8, as well as VEGF were elevated in the plasma of these patients and found to be expressed within the tumors. CXCR2 was found to be expressed on endothelial cells within the tumors. To assess the role of ELR+ CXC chemokines in RCC, we next used a model of syngeneic RCC (i.e., RENCA) in BALB/c mice. CXCR2 ligand and VEGF expression temporally increased in direct correlation with RENCA growth in CXCR2+/+ mice. However, there was a marked reduction of RENCA tumor growth in CXCR2−/− mice, which correlated with decreased angiogenesis and increased tumor necrosis. Furthermore, in the absence of CXCR2, orthotopic RENCA tumors demonstrated a reduced potential to metastasize to the lungs of CXCR2−/− mice. These data support the notion that CXCR2/CXCR2 ligand biology is an important component of RCC tumor-associated angiogenesis and tumorigenesis.
- Published
- 2005
15. Direct identification of bacteria from positive BacT/ALERT blood culture bottles using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry
- Author
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Jennifer Dien Bard, Javier Mestas, and Susanna Felsenstein
- Subjects
Microbiology (medical) ,Bacteriological Techniques ,Lysis ,Chromatography ,Time Factors ,medicine.diagnostic_test ,Bacteria ,Bact alert ,Matrix assisted laser desorption ionization time of flight ,Bacteremia ,General Medicine ,Biology ,Mass spectrometry ,biology.organism_classification ,Sensitivity and Specificity ,Microbiology ,Infectious Diseases ,Blood ,Blood culture bottles ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,medicine ,Humans ,Blood culture ,Identification (biology) - Abstract
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry is a fast and robust method for the identification of bacteria. In this study, we evaluate the performance of a laboratory-developed lysis method (LDT) for the rapid identification of bacteria from positive BacT/ALERT blood culture bottles. Of the 168 positive bottles tested, 159 were monomicrobial, the majority of which were Gram-positive organisms (61.0% versus 39.0%). Using a cut-off score of ≥1.7, 80.4% of the organisms were correctly identified to the species level, and the identification rate of Gram-negative organisms (90.3%) was found to be significantly greater than that of Gram-positive organisms (78.4%). The simplicity and cost-effectiveness of the LDT enable it to be fully integrated into the routine workflow of the clinical microbiology laboratory, allowing for rapid identification of Gram-positive and Gram-negative bacteria within an hour of blood culture positivity.
- Published
- 2014
16. Mycophenolate mofetil decreases atherosclerotic lesion size by depression of aortic T-lymphocyte and interleukin-17-mediated macrophage accumulation
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Joseph L. Witztum, Sibylle von Vietinghoff, Javier Mestas, Cody J. Diehl, Klaus Ley, and Ekaterina K. Koltsova
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Apolipoprotein E ,Male ,medicine.medical_treatment ,T-Lymphocytes ,T cells ,Aortic Diseases ,macrophage ,Pharmacology ,Mycophenolate ,Mycophenolic acid ,Article ,Lesion ,Mice ,Apolipoproteins E ,medicine ,Macrophage ,vascular inflammation ,Animals ,Mice, Knockout ,immunosuppression ,business.industry ,Macrophages ,Interleukin-17 ,Immunosuppression ,T lymphocyte ,Mycophenolic Acid ,Atherosclerosis ,Mice, Inbred C57BL ,Immunology ,lipids (amino acids, peptides, and proteins) ,Female ,Interleukin 17 ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,interleukin 17 ,Immunosuppressive Agents ,medicine.drug - Abstract
ObjectivesThis study tested whether immunosuppression with mycophenolate mofetil (MMF) inhibits atherosclerosis development in apolipoprotein-E–deficient (Apoe−/−) mice and investigated the mechanism.BackgroundChronic vascular inflammation involving both innate and adaptive immunity is central in the development of atherosclerosis, but immunosuppressive treatment is not uniformly beneficial. The immunosuppressive MMF targets lymphocyte proliferation by inhibiting inosine-monophosphate dehydrogenase.MethodsYoung and aged Apoe−/− mice were treated with 30 mg/kg daily MMF during 12 and 3 weeks of a high-fat diet, respectively. Aortic lesion size and composition was investigated by histology and flow cytometry; soluble inflammatory mediators were investigated by enzyme-linked immunosorbent assay.ResultsMacroscopic and histologic aortic atherosclerotic lesions were significantly decreased in both MMF-treated groups. While systemic immunoglobulin G directed against low-density lipoproteins was not significantly altered, the T-cell cytokine interleukin (IL)-17 was significantly reduced in plasma of MMF-treated mice and supernatants from their aortas after T-cell stimulation. The MMF treatment decreased aortic αβ T-cell receptor+ lymphocyte proliferation and cell numbers. Also, aortic contents of CD11b+CD11c+ cells and their proliferation were reduced in MMF-treated Apoe−/− mice. The IL-17 supplementation restored the number of proliferating aortic CD11b+CD11c+ cells in MMF-treated mice. The IL-17 receptor A was highly expressed on circulating monocytes that are macrophage progenitors. Genetic deletion of IL-17 receptor A or IL-17A reduced inflammatory peritoneal CD11b+CD11c+ macrophage accumulation.ConclusionsThe lymphocyte-directed immunosuppressant MMF that curbs IL-17 production was a successful antiatherosclerotic treatment. Our data delineate a role for IL-17 in CD11b+CD11c+ cell accumulation.
- Published
- 2010
17. Chapter 11. Intravital microscopic investigation of leukocyte interactions with the blood vessel wall
- Author
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Klaus, Ley, Javier, Mestas, Maria K, Pospieszalska, Prithu, Sundd, Alexander, Groisman, and Alexander, Zarbock
- Subjects
Microscopy, Fluorescence ,Microcirculation ,Cell Adhesion ,Leukocytes ,Animals ,Humans ,Cell Communication ,Endothelium, Vascular - Abstract
Intravital microscopy is a method to study the microcirculation in living tissues. Transillumination, oblique reflected light illumination, continuous and stroboscopic epifluorescence microscopy can be used to visualized specific cells and molecules. Intravital microscopy is further enhanced by the advent of laser scanning.spinning disk confocal and multi-photon microscopy. Recent advances include blood-perfused flow chambers and microfluidic devises for the study of blood cell interactions with molecularly defined substrates. This chapter focuses on the application of these techniques to study leukocyte interactions with the vascular wall and molecular surfaces.
- Published
- 2008
18. Chapter 11 Intravital Microscopic Investigation of Leukocyte Interactions with the Blood Vessel Wall
- Author
-
Javier Mestas, Alex Groisman, Klaus Ley, Alexander Zarbock, Maria K. Pospieszalska, and Prithu Sundd
- Subjects
Vascular wall ,medicine.anatomical_structure ,Materials science ,Confocal ,Microscopy ,Fluorescence microscope ,Biophysics ,medicine ,Transillumination ,Intravital microscopy ,Microcirculation ,Blood vessel ,Cell biology - Abstract
Intravital microscopy is a method to study the microcirculation in living tissues. Transillumination, oblique reflected light illumination, continuous and stroboscopic epifluorescence microscopy can be used to visualized specific cells and molecules. Intravital microscopy is further enhanced by the advent of laser scanning.spinning disk confocal and multi-photon microscopy. Recent advances include blood-perfused flow chambers and microfluidic devises for the study of blood cell interactions with molecularly defined substrates. This chapter focuses on the application of these techniques to study leukocyte interactions with the vascular wall and molecular surfaces.
- Published
- 2008
19. The Mouse TrapHow Well Do Mice Model Human Immunology?
- Author
-
Javier Mestas and Christopher C.W. Hughes
- Subjects
Immunology ,Selective advantage ,Model system ,In patient ,Disease ,Biology - Abstract
Publisher Summary Mice have proved to be such good models that people tempt to assume that what is true in mice is necessarily true in human. The differences between human and mouse immunology are significant and numerous. Although recent sequencing efforts reveal only 300 or so genes that are unique to mouse or human, it should not be forgotten that the two species diverged around 75 million years ago, differ hugely in both size and life-span, and have evolved in quite different ecological niches in which widely different pathogenic challenges need to be met. Most, if not all, of the differences that have been noted between mouse and human immunology have probably become fixed during the 75 million years since the divergence because they provide some selective advantage. In all likelihood these adaptations are in response to new pathological challenges from microorganisms, which have very short generation times and often have high mutation rates. The studies in mice highlight how caution is required when results from mouse studies are extrapolated to the clinic. In many cases not only successful mouse therapies fail to work in the clinic, they actually have opposite effects in patients, leading to exacerbation of disease. Although the mouse continues to be an important preclinical model system, it is a dangerous trap to fall into if one believes that what is true in mouse must be true in human.
- Published
- 2007
20. The candidate tumor suppressor gene ING4 is down‐regulated in human lung cancer and correlates with an increase in ELR+ CXC chemokines
- Author
-
Javier Mestas, Robert M. Strieter, and Marie D. Burdick
- Subjects
CxC chemokine ,Human lung cancer ,Genetics ,Cancer research ,Biology ,Molecular Biology ,Biochemistry ,Candidate Tumor Suppressor Gene ,Biotechnology - Published
- 2006
21. Cancer CXC chemokine networks and tumour angiogenesis
- Author
-
Brigitte N. Gomperts, Javier Mestas, Marie D. Burdick, Robert M. Strieter, Michael P. Keane, and John A. Belperio
- Subjects
Cancer Research ,Immunity, Cellular ,Neovascularization, Pathologic ,Angiogenesis ,hemic and immune systems ,Angiogenesis Inhibitors ,respiratory system ,Biology ,CXCR3 ,biological factors ,CXCL1 ,CXCL2 ,Oncology ,Neoplasms ,Immunology ,Angiostatic Proteins ,Cancer research ,CXCL9 ,CXCL10 ,Humans ,CXC chemokine receptors ,CXCL14 ,Chemokines, CXC - Abstract
Chemokines have pleiotropic effects in regulating immunity, angiogenesis, stem cell trafficking, and mediating organ-specific metastases of cancer. In the context of angiogenesis, the CXC chemokine family is a unique group of cytokines known for their ability to behave in a disparate manner in the regulation of angiogenesis. The glutamic acid-leucine-arginine (ELR+) CXC chemokines are potent promoters of angiogenesis, and mediate their angiogenic activity via signal-coupling of CXCR2 on endothelium. By contrast, members of the CXC chemokine family, such as platelet factor-4 (PF4; CXCL4) and interferon-inducible CXC chemokines are potent inhibitors of angiogenesis, and use CXCR3 on endothelium to mediate their angiostatic activity. This review will discuss the biology of CXC chemokines in the context of angiogenesis related to cancer.
- Published
- 2006
22. CXCR2/CXCR2 ligand biology during lung transplant ischemia-reperfusion injury
- Author
-
Marie D. Burdick, Robert M. Strieter, Joseph P. Lynch, John A. Belperio, Abbas Ardehali, David A. Zisman, Michael P. Keane, Ying Ying Xue, Kurt Hong, Rajan Saggar, David J. Ross, Javier Mestas, and Brigitte N. Gomperts
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Neutrophils ,medicine.medical_treatment ,Immunology ,Bronchiolitis obliterans ,Lung injury ,Ligands ,Receptors, Interleukin-8B ,Immunology and Allergy ,Medicine ,Lung transplantation ,Animals ,Humans ,CXC chemokine receptors ,Prospective Studies ,Lung ,medicine.diagnostic_test ,Base Sequence ,business.industry ,DNA ,Lung Injury ,respiratory system ,Middle Aged ,medicine.disease ,respiratory tract diseases ,Rats ,Transplantation ,Disease Models, Animal ,Bronchoalveolar lavage ,medicine.anatomical_structure ,Case-Control Studies ,Reperfusion Injury ,Female ,business ,Reperfusion injury ,Chemokines, CXC ,Lung Transplantation - Abstract
Lung transplantation is a therapeutic option for a number of end-stage pulmonary disorders. Early lung allograft dysfunction (ischemia-reperfusion injury) continues to be the most common cause of early mortality after lung transplantation and a significant risk factor for the development of bronchiolitis obliterans syndrome. Ischemia-reperfusion injury is characterized histopathologically by lung edema and a neutrophil predominate leukocyte extravasation. The specific mechanism(s) that recruit leukocytes to the lung during post-lung transplantation ischemia-reperfusion injury have not been fully elucidated. Because the ELR+ CXC chemokines are potent neutrophil chemoattractants, we investigated their role during post-lung transplantation ischemic-reperfusion injury. We found elevated levels of multiple ELR+ CXC chemokines in human bronchoalveolar lavage fluid from patients with ischemia-reperfusion injury. Proof of concept studies using a rat orthotopic lung transplantation model of “cold” ischemic-reperfusion injury demonstrated an increase in lung graft neutrophil sequestration and injury. In addition, lung expression of CXCL1, CXCL2/3, and their shared receptor CXCR2 paralleled lung neutrophil infiltration and injury. Importantly, inhibition of CXCR2/CXCR2 ligand interactions in vivo led to a marked reduction in lung neutrophil sequestration and graft injury. Taken together these experiments support the notion that increased expression of ELR+ CXC chemokines and their interaction with CXCR2 plays an important role in the pathogenesis of post-lung transplantation cold ischemia-reperfusion injury.
- Published
- 2005
23. Endothelial cell co-stimulation through OX40 augments and prolongs T cell cytokine synthesis by stabilization of cytokine mRNA
- Author
-
Javier Mestas, Steve P. Crampton, Toshiyuki Hori, and Christopher C.W. Hughes
- Subjects
CD4-Positive T-Lymphocytes ,Umbilical Veins ,medicine.medical_treatment ,T cell ,RNA Stability ,Immunology ,OX40 Ligand ,Cell Communication ,Biology ,p38 Mitogen-Activated Protein Kinases ,Receptors, Tumor Necrosis Factor ,Interleukin 21 ,T-Lymphocyte Subsets ,medicine ,Immunology and Allergy ,Cytotoxic T cell ,Humans ,IL-2 receptor ,RNA, Messenger ,Phosphorylation ,Protein kinase A ,Cells, Cultured ,Cell Proliferation ,Membrane Glycoproteins ,ZAP70 ,Endothelial Cells ,General Medicine ,Receptors, OX40 ,Cell biology ,Cytokine ,medicine.anatomical_structure ,Gene Expression Regulation ,Tumor Necrosis Factors ,Cancer research ,Cytokines ,Signal transduction ,Signal Transduction - Abstract
Human endothelial cells (ECs) constitutively express OX40L and co-stimulate memory CD4(+) T cell proliferation that is dependent upon OX40-OX40L interaction. In vivo, OX40 prolongs T cell survival; however, an unanswered question is whether it can also prolong synthesis of proliferation-sustaining cytokines such as IL-2. Here we show that EC co-stimulation results in the secretion of T cell IL-2, IL-3 and IFN-gamma and that in the absence of OX40 signals synthesis largely ceases by 12-18 h, but is prolonged up to 60 h in the presence of OX40 signaling. Blocking OX40-mediated cytokine expression at later times suppresses T cell proliferation and this can be overcome by addition of exogenous IL-2. We find that OX40 signaling has discrete effects on T cell activation as it does not affect expression of IL-10, CD25, CD69 or soluble IL-2R. Also, OX40 does not appear to alter IL-2 transcription, but rather acts to stabilize a subset of cytokine mRNAs, increasing their half-lives by 3-6-fold. We further show that OX40L induces activation of p38 mitogen-activated protein kinase (MAPK) and phosphotidyl-inositol-3-kinase (PI3K) in T cells, and using specific inhibitors, we find that increased mRNA half-life is dependent upon both these pathways but is independent of c-jun-N-terminal kinase (JNK). Thus, EC co-stimulation through OX40 leads to prolonged T cell cytokine synthesis and enhanced proliferation.
- Published
- 2005
24. Role of CXCR2/CXCR2 ligands in vascular remodeling during bronchiolitis obliterans syndrome
- Author
-
John A. Belperio, Michael P. Keane, Marie D. Burdick, Brigitte Gomperts, Ying Ying Xue, Kurt Hong, Javier Mestas, Abbas Ardehali, Borna Mehrad, Rajan Saggar, Joseph P. Lynch, David J. Ross, and Robert M. Strieter
- Subjects
Neovascularization, Pathologic ,Animals ,Humans ,hemic and immune systems ,General Medicine ,respiratory system ,Bronchiolitis Obliterans ,Chemokines, CXC ,Fibrosis ,humanities ,Article - Abstract
Angiogenesis and vascular remodeling support fibroproliferative processes; however, no study has addressed the importance of angiogenesis during fibro-obliteration of the allograft airway during bronchiolitis obliterans syndrome (BOS) that occurs after lung transplantation. The ELR+ CXC chemokines both mediate neutrophil recruitment and promote angiogenesis. Their shared endothelial cell receptor is the G-coupled protein receptor CXC chemokine receptor 2 (CXCR2). We found that elevated levels of multiple ELR+ CXC chemokines correlated with the presence of BOS. Proof-of-concept studies using a murine model of BOS not only demonstrated an early neutrophil infiltration but also marked vascular remodeling in the tracheal allografts. In addition, tracheal allograft ELR+ CXC chemokines were persistently expressed even in the absence of significant neutrophil infiltration and were temporally associated with vascular remodeling during fibro-obliteration of the tracheal allograft. Furthermore, in neutralizing studies, treatment with anti-CXCR2 Abs inhibited early neutrophil infiltration and later vascular remodeling, which resulted in the attenuation of murine BOS. A more profound attenuation of fibro-obliteration was seen when CXCR2–/– mice received cyclosporin A. This supports the notion that the CXCR2/CXCR2 ligand biological axis has a bimodal function during the course of BOS: early, it is important for neutrophil recruitment and later, during fibro-obliteration, it is important for vascular remodeling independent of neutrophil recruitment.
- Published
- 2005
25. Epidermal growth factor and hypoxia-induced expression of CXC chemokine receptor 4 on non-small cell lung cancer cells is regulated by the phosphatidylinositol 3-kinase/PTEN/AKT/mammalian target of rapamycin signaling pathway and activation of hypoxia inducible factor-1alpha
- Author
-
Roderick J. Phillips, Antonio Sica, Marie D. Burdick, Michael P. Keane, Mehrnaz Gharaee-Kermani, John A. Belperio, Robert M. Strieter, and Javier Mestas
- Subjects
Lung Neoplasms ,Transcription, Genetic ,Cell Separation ,Biochemistry ,Phosphatidylinositol 3-Kinases ,Epidermal growth factor ,Carcinoma, Non-Small-Cell Lung ,Epidermal growth factor receptor ,CXC chemokine receptors ,Neoplasm Metastasis ,Hypoxia ,Promoter Regions, Genetic ,biology ,Chemotaxis ,TOR Serine-Threonine Kinases ,Flow Cytometry ,Cell biology ,Up-Regulation ,Hypoxia-inducible factors ,Signal transduction ,Chemokines, CXC ,Signal Transduction ,Transcriptional Activation ,Receptors, CXCR4 ,Cell Survival ,Blotting, Western ,Protein Serine-Threonine Kinases ,Transfection ,Cell surface receptor ,Cell Line, Tumor ,Proto-Oncogene Proteins ,PTEN ,Humans ,RNA, Messenger ,Molecular Biology ,Protein kinase B ,Cell Proliferation ,Sirolimus ,Dose-Response Relationship, Drug ,Epidermal Growth Factor ,Tumor Suppressor Proteins ,PTEN Phosphohydrolase ,Cell Biology ,Hypoxia-Inducible Factor 1, alpha Subunit ,Chemokine CXCL12 ,Phosphoric Monoester Hydrolases ,Oxygen ,biology.protein ,Cancer research ,Protein Kinases ,Proto-Oncogene Proteins c-akt ,Transcription Factors - Abstract
Non-small cell lung cancer (NSCLC) expresses a particularly aggressive metastatic phenotype, and patients with this disease have a poor prognosis. CXC chemokine receptor 4 (CXCR4) is a cell surface receptor that has been shown to mediate the metastasis of many solid tumors including lung, breast, kidney, and prostate. In addition, overexpression of the epidermal growth factor receptor (EGFR) is associated with the majority of NSCLC and has been implicated in the process of malignant transformation by promoting cell proliferation, cell survival, and motility. Here we show for the first time that activation of the EGFR by EGF increases CXCR4 expression and the migratory capacity of NSCLC cells. Furthermore, many solid tumors are associated with low oxygen tension, and when NSCLC cells were cultured with EGF under hypoxic conditions, CXCR4 expression was dramatically enhanced. A molecular analysis of these events indicated that augmented CXCR4 expression was regulated by the phosphatidylinositol 3-kinase/PTEN/AKT/mammalian target of rapamycin signal transduction pathway, activation of hypoxia inducible factor (HIF) 1alpha, and ultimately HIF-1-dependent transcription of the CXCR4 gene. Thus, a combination of low oxygen tension and overexpression of EGFR within the primary tumor of NSCLC may provide the microenvironmental signals necessary to upregulate CXCR4 expression and promote metastasis.
- Published
- 2005
26. Of mice and not men: differences between mouse and human immunology
- Author
-
Christopher C.W. Hughes and Javier Mestas
- Subjects
Chemokine ,biology ,ZAP70 ,T cell ,Immunology ,Acquired immune system ,Chemokine receptor ,Disease Models, Animal ,Mice ,medicine.anatomical_structure ,Immune system ,Immune System Diseases ,Species Specificity ,Immune System ,Models, Animal ,medicine ,biology.protein ,Immunology and Allergy ,Animals ,Humans ,Receptor ,B cell - Abstract
Mice are the experimental tool of choice for the majority of immunologists and the study of their immune responses has yielded tremendous insight into the workings of the human immune system. However, as 65 million years of evolution might suggest, there are significant differences. Here we outline known discrepancies in both innate and adaptive immunity, including: balance of leukocyte subsets, defensins, Toll receptors, inducible NO synthase, the NK inhibitory receptor families Ly49 and KIR, FcR, Ig subsets, the B cell (BLNK, Btk, and λ5) and T cell (ZAP70 and common γ-chain) signaling pathway components, Thy-1, γδ T cells, cytokines and cytokine receptors, Th1/Th2 differentiation, costimulatory molecule expression and function, Ag-presenting function of endothelial cells, and chemokine and chemokine receptor expression. We also provide examples, such as multiple sclerosis and delayed-type hypersensitivity, where complex multicomponent processes differ. Such differences should be taken into account when using mice as preclinical models of human disease.
- Published
- 2004
27. Identification of endothelial cell genes expressed in an in vitro model of angiogenesis: induction of ESM-1, (beta)ig-h3, and NrCAM
- Author
-
Martin N. Nakatsu, Javier Mestas, Christopher C.W. Hughes, Shur-Jen Wang, Mark Aitkenhead, and Cheryl Heard
- Subjects
DNA, Complementary ,Angiogenesis ,Neovascularization, Physiologic ,Biology ,Biochemistry ,Models, Biological ,Extracellular matrix ,Transforming Growth Factor beta ,Gene expression ,Animals ,Humans ,Tissue Distribution ,Cloning, Molecular ,Cells, Cultured ,Extracellular Matrix Proteins ,Neovascularization, Pathologic ,Cell adhesion molecule ,Reverse Transcriptase Polymerase Chain Reaction ,Cell Biology ,Transforming growth factor beta ,Oligonucleotides, Antisense ,Blotting, Northern ,Molecular biology ,Kidney Neoplasms ,Neoplasm Proteins ,Rats ,Endothelial stem cell ,Alternative Splicing ,biology.protein ,RNA ,Proteoglycans ,Endothelium, Vascular ,Representational difference analysis ,Cardiology and Cardiovascular Medicine ,Cell Adhesion Molecules ,Annexin A2 ,Cell Division - Abstract
Blood vessel growth by angiogenesis plays an essential role in embryonic development, wound healing, and tumor growth. To understand the molecular cues underlying this process we have used the PCR-based subtractive hybridization method, representational difference analysis, to identify genes upregulated in endothelial cells (EC) forming tubes in 3D collagen gels, compared to migrating and proliferating cells in 2D cultures. We identified several previously characterized angiogenic markers, including the alpha(v) chain of the alpha(v)beta3 integrin and plasminogen activator inhibitor-1, suggesting overlap in gene expression between tube-forming cells in vitro and in vivo. We also found a 2- to 10-fold upregulation of (beta)ig-h3 (a collagen-binding extracellular matrix protein), NrCAM (a "neural" cell adhesion molecule), Annexin II (a tPA receptor), ESM-1 (an EC-specific molecule of unknown function), and Id2 (an inhibitory bHLH transcription factor). We identified a novel splice variant of the ESM-1 gene and also detected dramatically enhanced expression of ESM-1 and (beta)ig-h3 in several tumors. Antisense oligonucleotides to (beta)ig-h3 blocked both gene expression and tube formation in vitro, suggesting that (beta)ig-h3 may play a critical role in EC-matrix interactions. These data expand the suite of genes implicated in vascular remodeling and angiogenesis.
- Published
- 2002
28. Endothelial cell costimulation of T cell activation through CD58-CD2 interactions involves lipid raft aggregation
- Author
-
Javier Mestas and Christopher C.W. Hughes
- Subjects
Cell signaling ,T cell ,T-Lymphocytes ,Immunology ,CD2 Antigens ,Receptors, Antigen, T-Cell ,Cell Communication ,Biology ,Lymphocyte Activation ,Membrane Microdomains ,medicine ,Immunology and Allergy ,Memory T cell activation ,Humans ,Lipid raft ,Transcription factor ,Reporter gene ,Effector ,T-cell receptor ,Genes, fos ,Receptor Cross-Talk ,CD58 Antigens ,Molecular biology ,medicine.anatomical_structure ,Intercellular Junctions ,Endothelium, Vascular ,Transcription Factors - Abstract
Human endothelial cells (EC) costimulate CD4+ memory T cell activation through CD58-CD2 interactions. In this study we tested the hypothesis that EC activate distinct costimulatory pathways in T cells that target specific transcription factors. AP-1, composed of fos and jun proteins, is a critical effector of TCR signaling and binds several sites in the IL-2 promoter. EC augment c-fos promoter activity in T cells; however, deletion analysis reveals no transcription factor binding sites in the promoter uniquely responsive to EC costimulation. Overexpression of AP-1 proteins in T cells augments the activity of an AP-1-luciferase reporter gene equally in the absence or the presence of EC costimulation. Interestingly, EC stimulate a similar 2- to 3-fold up-regulation of AP-1, NF-AT, NF-κB, and NF-IL-2-luciferase reporters. CD2 mAbs completely block EC effects on all of these pathways, as well as costimulation of IL-2 secretion. We conclude that EC costimulation through CD2 does not trigger a single distinct costimulatory pathway in T cells, but rather, it amplifies several pathways downstream of the TCR. Indeed, we find that early EC costimulation acts “upstream” of the TCR by promoting lipid raft aggregation, thus amplifying TCR signaling. Soluble CD2 mAbs block EC-induced raft aggregation, whereas cross-linking CD2 promotes aggregation. These data are consistent with the critical role of CD2 in organizing the T cell-APC contact zone.
- Published
- 2001
29. Single-cell analysis of costimulation by B cells, endothelial cells, and fibroblasts demonstrates heterogeneity in responses of CD4(+) memory T cells
- Author
-
Javier Mestas, Christopher C.W. Hughes, Lisa L. Salazar Murphy, Angela C. Taylor, and Melissa M. Mazanet
- Subjects
CD4-Positive T-Lymphocytes ,T cell ,Immunology ,Antigen presentation ,Bacterial Toxins ,CD1 ,Biology ,Muscle, Smooth, Vascular ,Enterotoxins ,medicine ,Cytotoxic T cell ,Humans ,IL-2 receptor ,Antigen-presenting cell ,Cells, Cultured ,MHC class II ,Antigen Presentation ,B-Lymphocytes ,CD40 ,Superantigens ,Macrophages ,Models, Immunological ,Fibroblasts ,Molecular biology ,Coculture Techniques ,Cell biology ,medicine.anatomical_structure ,biology.protein ,Leukocyte Common Antigens ,Endothelium, Vascular ,Immunologic Memory - Abstract
Human endothelial cells (EC) express MHC class II molecules in vivo and are likely to be involved in presentation of antigens to CD4 + T cells. We examined, at the single-cell level, EC presentation of superantigens to resting CD4 + memory T cells. Within 2 h of adherence to class II + EC early T cell activation is evidenced by translocation of nuclear factor of activated T cells (NFAT), surface expression of CD69, and synthesis of IFN-γ and IL-2. Naive T cells are not activated. T cell activation is dependent on the prior induction of MHC class II molecules on EC and is blocked by antibodies to LFA-3 (CD58). Our data place EC along a spectrum of antigen-presenting ability. Activated B cells and macrophages trigger more cells to express cytokines than do EC and at lower antigen concentrations; EC are in turn, superior to fibroblasts or smooth muscle cells. Furthermore, the concept of activation thresholds for cytokine synthesis within T cells also extends to earlier activation events: NFAT translocation is relatively easy to trigger, as is CD69 expression; fewer cells can be triggered to express IFN-γ and fewer still to express IL-2. EC may, therefore, contribute to a graded immune response by inducing qualitatively and quantitatively different responses than professional APC.
- Published
- 1999
30. Inhibition of T cell proliferation decreases atherosclerotic lesion size revealing a role of IL-17 in mediating aortic CD11b+CD11c+ cell accumulation (35.4)
- Author
-
Sibylle von Vietinghoff, Ekaterina Koltsova, Javier Mestas, and Klaus Ley
- Subjects
Immunology ,Immunology and Allergy - Abstract
Atherosclerosis is a chronic inflammatory disease of the artery wall with innate and adaptive immune components, however, immunosuppressive therapy is not uniformely beneficial. Mycophenolate suppresses lymphocyte proliferation by inhibiting inosine-monophosphate dehydrogenase. In this study, we tested whether mycophenolate inhibited atherosclerosis in apolipoprotein-E-deficient (Apoe-/-) mice. Apoe-/- mice treated with 30 mg/kg/day mycophenolate during 12 weeks of high fat diet showed significantly decreased aortic leukocyte infiltration. Flow cytometry at 3 and 12 weeks of high fat diet revealed significantly reduced aortic αβTCR+ cell content and reduced αβTCR+ cell proliferation as measured by BrdU incorporation. Aortic atherosclerotic lesion sizes were significantly reduced. Among T cell cytokines, IL-17 was significantly reduced in plasma of mycophenolate-treated mice. IL-17 receptor A was expressed on both blood monocytes and aortic CD11b+CD11c+ cells. Proliferation and aortic content of CD11b+CD11c+ cells and plasma levels of IL-6 and TNF-α were reduced. CD11b+CD11c+ cells in aortas of IL-17 receptor deficient mice after 12 weeks of high fat diet were significantly reduced compared to wild-type mice. Our data suggest that that mycophenolate curbs IL-17 production, which in turn limits myeloid cell accumulation in atherosclerosis. Since mycophenolate is approved for human use, this suggests its potential application for prevention and/or therapy.
- Published
- 2010
31. Stromal Derived Factor-1 (SDF-1/CXCL12) and CXCR4 in renal cell carcinoma metastasis
- Author
-
Marie D. Burdick, Judong Pan, George Thomas, Karen L. Reckamp, Javier Mestas, Roderick J. Phillips, John A. Belperio, and Robert M. Strieter
- Subjects
Transcriptional Activation ,Cancer Research ,Receptors, CXCR4 ,Stromal cell ,Angiogenesis ,Mice, SCID ,Biology ,urologic and male genital diseases ,CXCR4 ,lcsh:RC254-282 ,Metastasis ,03 medical and health sciences ,Cytokeratin ,Mice ,0302 clinical medicine ,Renal cell carcinoma ,Cell Line, Tumor ,Carcinoma ,medicine ,Biomarkers, Tumor ,Animals ,Humans ,Promoter Regions, Genetic ,neoplasms ,Carcinoma, Renal Cell ,030304 developmental biology ,0303 health sciences ,Gene knockdown ,Research ,Chemotaxis ,medicine.disease ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Hypoxia-Inducible Factor 1, alpha Subunit ,female genital diseases and pregnancy complications ,Cell Hypoxia ,Chemokine CXCL12 ,Kidney Neoplasms ,3. Good health ,Gene Expression Regulation, Neoplastic ,Oncology ,Von Hippel-Lindau Tumor Suppressor Protein ,030220 oncology & carcinogenesis ,Cancer research ,Molecular Medicine ,Keratins ,RNA Interference ,Chemokines, CXC - Abstract
Renal cell carcinoma (RCC) is characterized by organ-specific metastases. The chemokine stromal derived factor-1 (SDF-1/CXCL12) and its receptor CXCR4 have been suggested to regulate organ-specific metastasis in various other cancers. On this basis, we hypothesized that the biological axis of CXCL12 via interaction with its receptor, CXCR4, is a major mechanism for RCC metastasis. We demonstrated that CXCR4 was significantly expressed on circulating cytokeratin+ RCC cells from patients with known metastatic RCC. We detected up-regulation of CXCR4 mRNA and protein levels on a human RCC cell line by either knockdown of the von Hippel-Lindau (VHL) tumor suppressor protein, or incubating the cells under hypoxic conditions. The enhanced CXCR4 expression was mediated through the interaction of the Hypoxia Inducible Factor-1α (HIF-1α) with the promoter region of the CXCR4 gene. Furthermore, the expression of CXCR4 on human RCC directly correlated with their metastatic ability in vivo in both heterotopic and orthotopic SCID mouse models of human RCC. Neutralization of CXCL12 in SCID mice abrogated metastasis of RCC to target organs expressing high levels of CXCL12; without altering tumor cell proliferation, apoptosis, or tumor-associated angiogenesis. Therefore, our data suggest that the CXCL12/CXCR4 biological axis plays an important role in regulating the organ-specific metastasis of RCC.
- Published
- 2006
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