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Xi Z, Xie J, Hu J, Wang QC, Wang Z, Yang X, Zong L, Zhang M, Sun X, Sun S, Han J. Polyvinylpyrrolidone-Coated Cubic Hollow Nanocages of PdPt 3 and PdIr 3 as Highly Efficient Self-Cascade Uricase/Peroxidase Mimics. Nano Lett 2024; 24:3432-3440. [PMID: 38391135 DOI: 10.1021/acs.nanolett.4c00071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Uricase-catalyzed uric acid (UA) degradation has been applied for hyperuricemia therapy, but this medication is limited by H2O2 accumulation, which can cause oxidative stress of cells, resulting in many other health issues. Herein, we report a robust cubic hollow nanocage (HNC) system based on polyvinylpyrrolidone-coated PdPt3 and PdIr3 to serve as highly efficient self-cascade uricase/peroxidase mimics to achieve the desired dual catalysis for both UA degradation and H2O2 elimination. These HNCs have hollow cubic shape with average wall thickness of 1.5 nm, providing desired synergy to enhance catalyst's activity and stability. Density functional theory calculations suggest the PdIr3 HNC surface tend to promote OH*/O* desorption for better peroxidase-like catalysis, while the PdPt3 HNC surface accelerates the UA oxidation by facilitating O2-to-H2O2 conversion. The dual catalysis power demonstrated by these HNCs in cell studies suggests their great potential as a new type of nanozyme for treating hyperuricemia.
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Affiliation(s)
- Zheng Xi
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Jing Xie
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Jun Hu
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Qin-Chao Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Ziyu Wang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Xiaoqiao Yang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Liying Zong
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Mengyao Zhang
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Xiaohuan Sun
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
| | - Shouheng Sun
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States
| | - Jie Han
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou, Jiangsu 225002, China
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Basnet A, Landreth KM, Nohoesu R, Santiago SP, Geldenhuys WJ, Boone BA, Liu TW. Targeting myeloperoxidase limits myeloid cell immunosuppression enhancing immune checkpoint therapy for pancreatic cancer. Cancer Immunol Immunother 2024; 73:57. [PMID: 38367056 PMCID: PMC10874341 DOI: 10.1007/s00262-024-03647-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/29/2024] [Indexed: 02/19/2024]
Abstract
Pancreatic ductal adenocarcinoma is a devastating disease characterized by an extreme resistance to current therapies, including immune checkpoint therapy. The limited success of immunotherapies can be attributed to a highly immunosuppressive pancreatic cancer microenvironment characterized by an extensive infiltration of immune suppressing myeloid cells. While there are several pathways through which myeloid cells contribute to immunosuppression, one important mechanism is the increased production of reactive oxygen species. Here, we evaluated the contribution of myeloperoxidase, a myeloid-lineage restricted enzyme and primary source of reactive oxygen species, to regulate immune checkpoint therapy response in preclinical pancreatic cancer models. We compared treatment outcome, immune composition and characterized myeloid cells using wild-type, myeloperoxidase-deficient, and myeloperoxidase inhibitor treated wild-type mice using established subcutaneous pancreatic cancer models. Loss of host myeloperoxidase and pharmacological inhibition of myeloperoxidase in combination with immune checkpoint therapy significantly delayed tumor growth. The tumor microenvironment and systemic immune landscape demonstrated significant decreases in myeloid cells, exhausted T cells and T regulatory cell subsets when myeloperoxidase was deficient. Loss of myeloperoxidase in isolated myeloid cell subsets from tumor-bearing mice resulted in decreased reactive oxygen species production and T cell suppression. These data suggest that myeloperoxidase contributes to an immunosuppressive microenvironment and immune checkpoint therapy resistance where myeloperoxidase inhibitors have the potential to enhance immunotherapy response. Repurposing myeloperoxidase specific inhibitors may provide a promising therapeutic strategy to expand therapeutic options for pancreatic cancer patients to include immunotherapies.
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Affiliation(s)
- Angisha Basnet
- Department of Microbiology, Immunology, and Cell Biology, School of Medicine, West Virginia University, 64 Medical Center Drive, Morgantown, WV, 26506, USA
| | - Kaitlyn M Landreth
- Department of Microbiology, Immunology, and Cell Biology, School of Medicine, West Virginia University, 64 Medical Center Drive, Morgantown, WV, 26506, USA
| | - Remi Nohoesu
- Department of Microbiology, Immunology, and Cell Biology, School of Medicine, West Virginia University, 64 Medical Center Drive, Morgantown, WV, 26506, USA
| | - Stell P Santiago
- Department of Pathology, Anatomy and Laboratory Medicine, West Virginia University, Morgantown, WV, 26506, USA
| | - Werner J Geldenhuys
- WVU Cancer Institute, West Virginia University, Morgantown, WV, 26506, USA
- Department of Pharmaceutical Sciences, West Virginia University, Morgantown, WV, 26506, USA
| | - Brian A Boone
- WVU Cancer Institute, West Virginia University, Morgantown, WV, 26506, USA
- Division of Surgical Oncology, Department of Surgery, West Virginia University, Morgantown, WV, 26506, USA
| | - Tracy W Liu
- Department of Microbiology, Immunology, and Cell Biology, School of Medicine, West Virginia University, 64 Medical Center Drive, Morgantown, WV, 26506, USA.
- WVU Cancer Institute, West Virginia University, Morgantown, WV, 26506, USA.
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Lam CSP, Lund LH, Shah SJ, Voors AA, Erlinge D, Saraste A, Pirazzi C, Grove EL, Barasa A, Schou M, Aziz A, Svedlund S, Wijngaarden JVAN, Lindstedt EL, Gustavsson A, Nelander K, Garkaviy P, Gan LM, Gabrielsen A. Myeloperoxidase Inhibition in Heart Failure With Preserved or Mildly Reduced Ejection Fraction: SATELLITE Trial Results. J Card Fail 2024; 30:104-110. [PMID: 37072105 DOI: 10.1016/j.cardfail.2023.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/06/2023] [Accepted: 04/06/2023] [Indexed: 04/20/2023]
Abstract
BACKGROUND Inflammation is a key driver of heart failure with preserved left ventricular ejection fraction. AZD4831 inhibits extracellular myeloperoxidase, decreases inflammation, and improves microvascular function in preclinical disease models. METHODS AND RESULTS In this double-blind phase 2a study (Safety and Tolerability Study of AZD4831 in Patients With Heart Failure [SATELLITE]; NCT03756285), patients with symptomatic heart failure, left ventricular ejection fraction of ≥40%, and elevated B-type natriuretic peptides were randomized 2:1 to once-daily oral AZD4831 5 mg or placebo for 90 days. We aimed to assess target engagement (primary end point: myeloperoxidase specific activity) and safety of AZD4831. Owing to coronavirus disease 2019, the study was terminated early after randomizing 41 patients (median age 74.0 years, 53.7% male). Myeloperoxidase activity was decreased by more than 50% from baseline to day 30 and day 90 in the AZD4831 group, with a placebo-adjusted decreased of 75% (95% confidence interval, 48, 88, nominal P < .001). No improvements were noted in secondary or exploratory end points, apart from a trend in Kansas City Cardiomyopathy Questionnaire overall summary score. No deaths or treatment-related serious adverse events occurred. AZD4831 treatment-related adverse events were generalized maculopapular rash, pruritus, and diarrhea (all n = 1). CONCLUSIONS AZD4831 inhibited myeloperoxidase and was well tolerated in patients with heart failure and left ventricular ejection fraction of 40% or greater. Efficacy findings were exploratory owing to early termination, but warrant further clinical investigation of AZD4831. LAY SUMMARY Few treatments are available for patients with the forms of heart failure known as heart failure with preserved or mildly reduced ejection fraction. Current treatments do not target inflammation, which may play an important role in this condition. We tested a new drug called AZD4831 (mitiperstat), which decreases inflammation by inhibiting the enzyme myeloperoxidase. Among the 41 patients in our clinical trial, AZD4831 had a good safety profile and inhibited myeloperoxidase by the expected amount. Results mean we can conduct further trials to see whether AZD4831 decreases the symptoms of heart failure and improves patients' ability to participate in physical exercise.
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Affiliation(s)
- Carolyn S P Lam
- National Heart Centre Singapore and Duke National University of Singapore, Singapore; University of Groningen and University Medical Centre Groningen, Groningen, the Netherlands.
| | - Lars H Lund
- Department of Medicine, Karolinska Institute, and Heart, Vascular and Neuro Theme, Karolinska University Hospital, Stockholm, Sweden
| | - Sanjiv J Shah
- Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Adriaan A Voors
- University of Groningen and University Medical Centre Groningen, Groningen, the Netherlands
| | | | - Antti Saraste
- Heart Centre, Turku University Hospital and University of Turku, Turku, Finland
| | - Carlo Pirazzi
- Department of Cardiology, Sahlgrenska University Hospital and Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Erik L Grove
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Morten Schou
- Department of Cardiology, Herlev and Gentofte Hospital, Copenhagen, Denmark
| | - Ahmed Aziz
- Odense University Hospital, Odense, Denmark
| | - Sara Svedlund
- Department of Clinical Physiology, Sahlgrenska University Hospital and Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | | | - Eva-Lotte Lindstedt
- Research and Early Clinical Development, Cardiovascular, Renal and Metabolic, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Andreas Gustavsson
- Early Biometrics and Statistical Innovation, Data Science and AI, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Karin Nelander
- Early Biometrics and Statistical Innovation, Data Science and AI, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Pavlo Garkaviy
- Research and Early Clinical Development, Cardiovascular, Renal and Metabolic, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Li-Ming Gan
- Department of Cardiology, Sahlgrenska University Hospital and Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Anders Gabrielsen
- Research and Early Clinical Development, Cardiovascular, Renal and Metabolic, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
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Yao Q, Chen P, Fu X. Rare myeloperoxidase-negative rectangular inclusions in acute promyelocytic leukemia after induction therapy. Pediatr Blood Cancer 2023; 70:e30702. [PMID: 37792304 DOI: 10.1002/pbc.30702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 09/20/2023] [Accepted: 09/21/2023] [Indexed: 10/05/2023]
Affiliation(s)
- Qiang Yao
- Department of Laboratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong, China
| | - Pu Chen
- Department of Laboratory Medicine, Zhongshan Hospital Fudan University, Shanghai, China
| | - Xiaoying Fu
- Department of Laboratory Medicine, Shenzhen Children's Hospital, Shenzhen, Guangdong, China
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Fleischman DA, Mauldin EA, Lowe A, Cain CL, Bradley CW. Clinical and histopathological features of rostrolateral nasal alar arteriopathy of German shepherd dogs. Vet Dermatol 2023; 34:441-451. [PMID: 37221296 DOI: 10.1111/vde.13173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 02/08/2023] [Accepted: 03/12/2023] [Indexed: 05/25/2023]
Abstract
BACKGROUND Dermal arteritis of the nasal philtrum (DANP) has been described in large-breed dogs. OBJECTIVES To characterise clinically distinct, discrete fissures of the dorsolateral nasal alae associated with severe bleeding in German shepherd dogs (GSDs). ANIMALS Fourteen privately owned GSDs with linear rostrolateral nasal alar fissures and a histopathological diagnosis of nasal vasculopathy. MATERIALS AND METHODS Retrospective analysis of medical records and histological slides. RESULTS Mean age of onset was 6 years. Before biopsy, episodic arteriolar bleeding was noted in 11 of the 14 (79%) dogs. Slide analysis revealed enlarged nasal arterioles with expanded vascular tunics and luminal stenosis beneath ulcers. Histopathological lesions consistent with mucocutaneous pyoderma and/or facial discoid lupus erythematosus were present in 5 of the 14 (36%) dogs. Enlarged arterioles stained blue with Alcian blue and Masson's trichrome stains, consistent with deposition of mucin and collagen, respectively. Immunohistochemical stains (neutrophil myeloperoxidase, IBA1, CD3) were performed. CD3 was negative for all dogs, whilst neutrophil myeloperoxidase and IBA1 occasionally demonstrated intramural neutrophils (3 of the 14 dogs, 21%) or histiocytes (1 of the 14 dogs, 7%) in altered vessels, respectively. All dogs underwent medical management and/or surgical excision. Treatments included tacrolimus, prednisone, ciclosporin-modified, pentoxifylline, antimicrobials and doxycycline/niacinamide. No dogs were treated with antimicrobials alone. For seven dogs with long-term follow-up, treatment response was complete in five (71%) and partial in two (29%), with six of the seven (86%) receiving immunomodulatory treatments to maintain remission. CONCLUSION AND CLINICAL RELEVANCE Nasal alar arteriopathy of GSDs shares histopathological changes with DANP. It has characteristic clinical and histopathological features and appears amenable to immunomodulation.
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Affiliation(s)
- Drew A Fleischman
- Departments of Clinical Sciences and Advanced Medicine and Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Elizabeth A Mauldin
- Departments of Clinical Sciences and Advanced Medicine and Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Andrew Lowe
- Alta Vista Animal Hospital, Ottawa, Ontario, Canada
| | - Christine L Cain
- Departments of Clinical Sciences and Advanced Medicine and Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Charles W Bradley
- Departments of Clinical Sciences and Advanced Medicine and Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Lund LH, Lam CS, Pizzato PE, Gabrielsen A, Michaëlsson E, Nelander K, Ericsson H, Holden J, Folkvaljon F, Mattsson A, Collén A, Aurell M, Whatling C, Baldus S, Drelich G, Goudev A, Merkely B, Bergh N, Shah SJ. Rationale and design of ENDEAVOR: A sequential phase 2b-3 randomized clinical trial to evaluate the effect of myeloperoxidase inhibition on symptoms and exercise capacity in heart failure with preserved or mildly reduced ejection fraction. Eur J Heart Fail 2023; 25:1696-1707. [PMID: 37470101 PMCID: PMC10592288 DOI: 10.1002/ejhf.2977] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 06/15/2023] [Accepted: 07/07/2023] [Indexed: 07/21/2023] Open
Abstract
AIMS Mitiperstat (formerly AZD4831) is a novel selective myeloperoxidase inhibitor. Currently, no effective therapies target comorbidity-induced systemic inflammation, which may be a key mechanism underlying heart failure with preserved or mildly reduced ejection fraction (HFpEF/HFmrEF). Circulating neutrophils secrete myeloperoxidase, causing oxidative stress, microvascular endothelial dysfunction, interstitial fibrosis, cardiomyocyte remodelling and diastolic dysfunction. Mitiperstat may therefore improve function of the heart and other organs, and ameliorate heart failure symptoms and exercise intolerance. ENDEAVOR is a combined, seamless phase 2b-3 study of the efficacy and safety of mitiperstat in patients with HFpEF/HFmrEF. METHODS In phase 2b, approximately 660 patients with heart failure and ejection fraction >40% are being randomized 1:1:1 to mitiperstat 2.5 mg, 5 mg or placebo for 48 weeks. Eligible patients have baseline 6-min walk distance (6MWD) of 30-400 m with a <50 m difference between screening and randomization and Kansas City Cardiomyopathy Questionnaire total symptom score (KCCQ-TSS) ≤90 points at screening and randomization. The dual primary endpoints are change from baseline to week 16 in 6MWD and KCCQ-TSS. The sample size provides 85% power to detect placebo-adjusted improvements of 21 m in 6MWD and 6.0 points in KCCQ-TSS at overall two-sided alpha of 0.05. Safety is monitored throughout treatment, with a focus on maculopapular rash. In phase 3 of ENDEAVOR, approximately 820 patients will be randomized 1:1 to mitiperstat or placebo. CONCLUSION ENDEAVOR is the first phase 2b-3 study to evaluate whether myeloperoxidase inhibition can improve symptoms and exercise capacity in patients with HFpEF/HFmrEF.
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Affiliation(s)
- Lars H. Lund
- Department of Medicine, Karolinska Institute, and Heart, Vascular and Neuro Theme, Karolinska University Hospital, Stockholm, Sweden
| | - Carolyn S.P. Lam
- National Heart Centre Singapore and Duke National University of Singapore, Singapore
| | - Patricia E. Pizzato
- Early Clinical Development, Research and Early Clinical Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anders Gabrielsen
- Early Clinical Development, Research and Early Clinical Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Erik Michaëlsson
- Early Clinical Development, Research and Early Clinical Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Karin Nelander
- Early Biometrics and Statistical Innovation, Data Science and AI, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Hans Ericsson
- Clinical Pharmacology and Quantitative Pharmacology, Clinical Pharmacology and Safety Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Julie Holden
- Patient Safety, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, USA
| | - Folke Folkvaljon
- Late-Stage Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Andrea Mattsson
- Late-Stage Development, Cardiovascular, Renal and Metabolism – Biometrics, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Anna Collén
- Projects, Research and Early Development, Cardiovascular, Renal and Metabolism, Biopharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Malin Aurell
- Early Clinical Development, Research and Early Clinical Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Carl Whatling
- Translational Science and Experimental Medicine, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Stephan Baldus
- Department of Internal Medicine and Cardiology, University Hospital Cologne, Cologne, Germany
| | | | - Assen Goudev
- Clinic of Cardiology, Tsaritsa Joanna University Hospital – ISUL, Sofia, Bulgaria
| | - Béla Merkely
- Heart and Vascular Center, Semmelweis University, Budapest, Hungary
| | - Niklas Bergh
- Department of Cardiology, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Sanjiv J. Shah
- Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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Zhao K, Hu F, Zhang Z, Yin X, Wang H, Li M. 0.01% Hypochlorous Acid Treats Aspergillus fumigatus Keratitis in Rats by Reducing Fungal Load and Inhibiting the Inflammatory Response. Transl Vis Sci Technol 2023; 12:3. [PMID: 37531113 PMCID: PMC10405862 DOI: 10.1167/tvst.12.8.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 05/26/2023] [Indexed: 08/03/2023] Open
Abstract
Purpose To investigate the antifungal and anti-inflammatory effects of 0.01% hypochlorous acid (HCLO) on rats with Aspergillus fumigatus keratitis. Methods The time-kill assay and broth microdilution procedures were used in vitro to demonstrate that 0.01% HCLO was fungicidal and fungistatic. The severity of the disease was evaluated in vivo using a clinical score and slit-lamp photographs. Fungal load, polymorphonuclear neutrophil infiltration, and the production of related proteins were determined using colony plate counting, in vivo confocal microscopy, periodic acid-Schiff staining, fungal fluorescence staining, immunofluorescence staining, myeloperoxidase assay, and Western blotting. Result In vitro, 0.01% HCLO can destroy A. fumigatus spores in 1 minute. The optical density of the 0.01% HCLO group was significantly lower than that of the phosphate-buffered saline control group (P < 0.01), and no visible mycelium was observed using a fluorescence microscope. 0.01% HCLO reduced the severity of A. fumigatus keratitis in rats by decreasing the clinical score, fungal loading (periodic acid-Schiff, plate count, and fungal fluorescence staining), and inhibiting neutrophil infiltration and activity (immunofluorescence staining and myeloperoxidase). Furthermore, the Western blot analysis revealed that 0.01% HCO decreased protein expression levels of tumor necrosis factor-α and IL-1β. Conclusions According to our findings, 0.01% HCLO can kill A. fumigatus spores in vitro. It has antifungal and anti-inflammatory effects on A. fumigatus keratitis in rats. It also inhibited A. fumigatus growth; decreased neutrophil infiltration, tumor necrosis factor-α, and IL-1β expression; and provided a potential treatment for fungal keratitis. Translational Relevance This study provides a potential treatment for fungal keratitis in the clinic.
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Affiliation(s)
- Kai Zhao
- Department of Ophthalmology, Xuzhou Medical University, Xuzhou, China
| | - Fen Hu
- Department of Ophthalmology, Xuzhou Medical University, Xuzhou, China
| | - Zhaowei Zhang
- Department of Ophthalmology, Xuzhou Medical University, Xuzhou, China
| | - Xiaoyue Yin
- Department of Ophthalmology, Xuzhou Medical University, Xuzhou, China
| | - He Wang
- Department of Ophthalmology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Mingxin Li
- Department of Ophthalmology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
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Pittman JE, Skalland MS, Sagel SD, Ramsey BW, Mayer-Hamblett N, Retsch-Bogart GZ. Impact of azithromycin on serum inflammatory markers in children with cystic fibrosis and new Pseudomonas. J Cyst Fibros 2022; 21:946-949. [PMID: 35260354 PMCID: PMC9441469 DOI: 10.1016/j.jcf.2022.02.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 11/24/2022]
Abstract
Chronic azithromycin improves outcomes in cystic fibrosis (CF), but its mechanism of action is unclear. The OPTIMIZE trial demonstrated improvement in time to first pulmonary exacerbation in children with new Pseudomonas treated with azithromycin. Azithromycin effect on systemic markers of inflammation over 18 months was assessed by change from baseline for high-sensitivity C-reactive protein, myeloperoxidase, calprotectin and absolute neutrophil count in the OPTIMIZE population. Subjects treated with chronic azithromycin or placebo had samples collected at baseline, 39 and 78 weeks of treatment. In 129 subjects, a significant decrease in high-sensitivity C-reactive protein was present at 39 weeks in the azithromycin group compared to placebo, but no significant difference between the groups at 78 weeks. No differences in change from baseline in myeloperoxidase, calprotectin or absolute neutrophil count were present at either time point. This supports the concept of a transient immunomodulatory effect for chronic azithromycin therapy in children with CF.
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Affiliation(s)
- Jessica E Pittman
- Department of Pediatrics, Washington University, St. Louis, MO, United States.
| | | | - Scott D Sagel
- Department of Pediatrics, Children's Hospital Colorado and University of Colorado Anschutz Medical Campus, Aurora, CO, United States.
| | - Bonnie W Ramsey
- Department of Pediatrics, University of Washington, Seattle, WA, United States; Seattle Children's Hospital, Seattle, WA, United States.
| | - Nicole Mayer-Hamblett
- Department of Pediatrics, University of Washington, Seattle, WA, United States; Seattle Children's Hospital, Seattle, WA, United States; Department of Biostatistics, University of Washington, Seattle, WA, United States.
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Frątczak A, Polak K, Miziołek B, Bergler-Czop B. Torasemide-induced Vascular Purpura in the Course of Eosinophilic Granulomatosis with Polyangiitis. Acta Dermatovenerol Croat 2022; 30:116-118. [PMID: 36254546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Torasemide is a loop diuretic with a molecule that is chemically similar to the sulphonamides described as eosinophilic granulomatosis with polyangiitis (EGPA) triggering drugs. The presented case is probably the first description of torasemide-induced vascular purpura in the course of EGPA. Any diagnosis of vasculitis should be followed by an identification of drugs that may aggravate the disease. A 74-year-old patient was admitted to the Department of Dermatology with purpura-like skin lesions on the upper, and lower extremities, including the buttocks. The lesions had appeared around the ankles 7 days before admission to the hospital and then started to progress upwards. The patient complained on lower limb paresthesia and pain. Other comorbidities included bronchial asthma, chronic sinusitis, ischemic heart disease, mild aortic stenosis, arterial hypertension, and degenerative thoracic spine disease. The woman had previously undergone nasal polypectomy twice. She was on a constant regimen of oral rosuvastatin 5 mg per day, spironolactone 50 mg per day, metoprolol 150 mg per day, inhaled formoterol 12 μg per day, and ipratropium bromide 20 μg per day. Ten days prior to admission, she was commenced on torasemide at a dose of 50 mg per day prescribed by a general practitioner due to high blood pressure. Doppler ultrasound upon admission to the hospital excluded deep venal thrombosis. The laboratory tests revealed leukocytosis (17.1 thousand per mm3) with eosinophilia (38.6%), elevated plasma level of C-reactive protein (119 mg per L) and D-dimers (2657 ng per mm3). Indirect immunofluorescent test identified a low titer (1:80) of antinuclear antibodies, but elevated (1:160) antineutrophil cytoplasmic antibodies (ANCA) in the patient's serum. Immunoblot found them to be aimed against myeloperoxidase (pANCA). A chest X-ray showed increased vascular lung markings, while high-resolution computed tomography revealed peribronchial glass-ground opacities. Microscopic evaluation of skin biopsy taken from the lower limbs showed perivascular infiltrates consisting of eosinophils and neutrophils, fragments of neutrophil nuclei, and fibrinous necrosis of small vessels. Electromyography performed in the lower limbs because of their weakness highlighted a loss of response from both sural nerves, as well as slowed conduction velocity of the right tibial nerve and in both common peroneal nerves. Both clinical characteristics of skin lesions and histopathology suggested a diagnosis of EGPA, which was later confirmed by a consultant in rheumatology. The patient was commenced on prednisone at a dose of 0.5 mg per kg of body weight daily and mycophenolate mofetil at a daily dose of 2 g. The antihypertensive therapy was modified, and torasemide was replaced by spironolactone 25 mg per day. The treatment resulted in a gradual regression of skin lesions within a few weeks. The first report of EGPA dates back to 1951. Its authors were Jacob Churg and Lotte Strauss. They described a case series of 13 patients who had severe asthma, fever, peripheral blood eosinophilia, and granulomatous vasculitis in microscopic evaluation of the skin. Three histopathological criteria were then proposed, and Churg-Strauss syndrome was recognized when eosinophilic infiltrates in the tissues, necrotizing inflammation of small and medium vessels, and the presence of extravascular granulomas were observed together in a patient (1). Only 17.4% of patients met all three histopathological criteria, and the diagnosis of the disease was frequently delayed despite of its overt clinical picture (2). In 1984, Lanham et al. proposed new diagnostic criteria which included the presence of bronchial asthma, eosinophilia in a peripheral blood smear >1.5 thousand per mm3, and signs of vasculitis involving at least two organs other than the lungs (3). Lanham's criteria could also delay the recognition of the syndrome before involvement of internal organs, and the American College of Rheumatology therefore established classification criteria in 1990. These included the presence of bronchial asthma, migratory infiltrates in the lungs as assessed by radiographs, the presence of abnormalities in the paranasal sinuses (polyps, allergic rhinitis, chronic inflammation), mono- or polyneuropathy, peripheral blood eosinophilia (>10% of leukocytes must be eosinophils), and extravascular eosinophilic infiltrates in a histopathological examination. Patients who met 4 out of 6 criteria were classified as having Churg-Strauss syndrome (4). The term EGPA was recommended to define patients with Churg-Strauss syndrome in 2012 (5). EGPA is a condition with low incidence (0.11-2.66 cases per million) and morbidity. It usually occurs in the fifth decade of life (6,7), although 65 cases reports of EGPA in people under 18 years of age could be found in the PubMed and Ovid Medline Database at the end of 2020 (8). The etiopathogenesis of the disease has not been fully explained so far. Approximately 40-60% of patients are positive to pANCA (9), but the role of these antibodies in the pathogenesis of EGPA remains unclear. They are suspected to mediate binding of the Fc receptor to MPO exposed on the surface of neutrophils. Subsequently, this may active neutrophils and contribute to a damage of the vascular endothelium (9,10). Glomerulonephritis, neuropathy, and vasculitis are more common in patients with EGPA who have detectable pANCA when compared with seronegative patients. There are at least several drugs which potentially may EGPA. The strongest association with the occurrence of EGPA was found with the use of leukotriene receptor antagonists (montelukast, zafirlukast, pranlukast), although they are commonly used in the treatment of asthma, which is paradoxically one of the complications of the syndrome (13). Although no relationship has been demonstrated so far between the occurrence of EGPA and the intake of drugs from the groups used by the presented patient, a clear time relationship can be observed between the commencement of torasemide and the onset of symptoms in our patient. To date, only three cases of leukocytoclastic vasculitis have been reported after the administration of torasemide. Both of them developed cutaneous symptoms of the disease within 24 hours of the administration of torasemide in patients with no previous history of drug hypersensitivity, but they disappeared quickly within 8-15 days after drug discontinuation (14,15). The chemical structure of torasemide is similar to the molecule of sulfonamides which were previously found to be a triggering factors for EGPA (12). This drug belongs to the group of loop diuretics classified as sulfonamide derivatives. A comparison of the chemical structure of torasemide and sulphanilamide molecules is presented in Figure 1. The clear time relationship between starting the administration of torasemide and the occurrence of purpura-like lesions suggests that it was an aggravating factor for EGPA in our patient. A coexistence of several disorders (asthma, nasal polyps, symptoms of peripheral neuropathy) in our patient suggest EGPA could have developed in her years before oral intake of torasemide. The sudden onset of skin symptoms shows torasemide to be possible inducing factor for the development of vascular purpura in patients suffering from EGPA but without previous cutaneous involvement.
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Affiliation(s)
- Aleksandra Frątczak
- Aleksandra Frątczak MD, Department of Dermatology, Medical University of Silesia, School of Medicine in Katowice, 20/24 Francuska St., 40-027 Katowice, Poland;
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10
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Jayne D, Walsh M, Merkel PA, Peh CA, Szpirt W, Puéchal X, Fujimoto S, Hawley C, Khalidi N, Jones R, Flossmann O, Wald R, Girard L, Levin A, Gregorini G, Harper L, Clark W, Pagnoux C, Specks U, Smyth L, Ito-Ihara T, de Zoysa J, Brezina B, Mazzetti A, McAlear CA, Reidlinger D, Mehta S, Ives N, Brettell EA, Jarrett H, Wheatley K, Broadhurst E, Casian A, Pusey CD. Plasma exchange and glucocorticoids to delay death or end-stage renal disease in anti-neutrophil cytoplasm antibody-associated vasculitis: PEXIVAS non-inferiority factorial RCT. Health Technol Assess 2022; 26:1-60. [PMID: 36155131 DOI: 10.3310/pnxb5040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Anti-neutrophil cytoplasm antibody-associated vasculitis is a multisystem, autoimmune disease that causes organ failure and death. Physical removal of pathogenic autoantibodies by plasma exchange is recommended for severe presentations, along with high-dose glucocorticoids, but glucocorticoid toxicity contributes to morbidity and mortality. The lack of a robust evidence base to guide the use of plasma exchange and glucocorticoid dosing contributes to variation in practice and suboptimal outcomes. OBJECTIVES We aimed to determine the clinical efficacy of plasma exchange in addition to immunosuppressive therapy and glucocorticoids with respect to death and end-stage renal disease in patients with severe anti-neutrophil cytoplasm antibody-associated vasculitis. We also aimed to determine whether or not a reduced-dose glucocorticoid regimen was non-inferior to a standard-dose regimen with respect to death and end-stage renal disease. DESIGN This was an international, multicentre, open-label, randomised controlled trial. Patients were randomised in a two-by-two factorial design to receive either adjunctive plasma exchange or no plasma exchange, and either a reduced or a standard glucocorticoid dosing regimen. All patients received immunosuppressive induction therapy with cyclophosphamide or rituximab. SETTING Ninety-five hospitals in Europe, North America, Australia/New Zealand and Japan participated. PARTICIPANTS Participants were aged ≥ 16 years with a diagnosis of granulomatosis with polyangiitis or microscopic polyangiitis, and either proteinase 3 anti-neutrophil cytoplasm antibody or myeloperoxidase anti-neutrophil cytoplasm antibody positivity, and a glomerular filtration rate of < 50 ml/minute/1.73 m2 or diffuse alveolar haemorrhage attributable to active anti-neutrophil cytoplasm antibody-associated vasculitis. INTERVENTIONS Participants received seven sessions of plasma exchange within 14 days or no plasma exchange. Oral glucocorticoids commenced with prednisolone 1 mg/kg/day and were reduced over different lengths of time to 5 mg/kg/day, such that cumulative oral glucocorticoid exposure in the first 6 months was 50% lower in patients allocated to the reduced-dose regimen than in those allocated to the standard-dose regimen. All patients received the same glucocorticoid dosing from 6 to 12 months. Subsequent dosing was at the discretion of the treating physician. PRIMARY OUTCOME The primary outcome was a composite of all-cause mortality and end-stage renal disease at a common close-out when the last patient had completed 10 months in the trial. RESULTS The study recruited 704 patients from June 2010 to September 2016. Ninety-nine patients died and 138 developed end-stage renal disease, with the primary end point occurring in 209 out of 704 (29.7%) patients: 100 out of 352 (28%) in the plasma exchange group and 109 out of 352 (31%) in the no plasma exchange group (adjusted hazard ratio 0.86, 95% confidence interval 0.65 to 1.13; p = 0.3). In the per-protocol analysis for the non-inferiority glucocorticoid comparison, the primary end point occurred in 92 out of 330 (28%) patients in the reduced-dose group and 83 out of 325 (26%) patients in the standard-dose group (partial-adjusted risk difference 0.023, 95% confidence interval 0.034 to 0.08; p = 0.5), thus meeting our non-inferiority hypothesis. Serious infections in the first year occurred in 96 out of 353 (27%) patients in the reduced-dose group and in 116 out of 351 (33%) patients in the standard-dose group. The rate of serious infections at 1 year was lower in the reduced-dose group than in the standard-dose group (incidence rate ratio 0.69, 95% confidence interval 0.52 to 0.93; p = 0.016). CONCLUSIONS Plasma exchange did not prolong the time to death and/or end-stage renal disease in patients with anti-neutrophil cytoplasm antibody-associated vasculitis with severe renal or pulmonary involvement. A reduced-dose glucocorticoid regimen was non-inferior to a standard-dose regimen and was associated with fewer serious infections. FUTURE WORK A meta-analysis examining the effects of plasma exchange on kidney outcomes in anti-neutrophil cytoplasm antibody-associated vasculitis is planned. A health-economic analysis of data collected in this study to examine the impact of both plasma exchange and reduced glucocorticoid dosing is planned to address the utility of plasma exchange for reducing early end-stage renal disease rates. Blood and tissue samples collected in the study will be examined to identify predictors of response to plasma exchange in anti-neutrophil cytoplasm in antibody-associated vasculitis. The benefits associated with reduced glucocorticoid dosing will inform future studies of newer therapies to permit further reduction in glucocorticoid exposure. Data from this study will contribute to updated management recommendations for anti-neutrophil cytoplasm antibody-associated vasculitis. LIMITATIONS This study had an open-label design which may have permitted observer bias; however, the nature of the end points, end-stage renal disease and death, would have minimised this risk. Despite being, to our knowledge, the largest ever trial in anti-neutrophil cytoplasm antibody-associated vasculitis, there was an insufficient sample size to assess clinically useful benefits on the separate components of the primary end-point: end-stage renal disease and death. Use of a fixed-dose plasma exchange regimen determined by consensus rather than data-driven dose ranging meant that some patients may have been underdosed, thus reducing the therapeutic impact. In particular, no biomarkers have been identified to help determine dosing in a particular patient, although this is one of the goals of the biomarker plan of this study. TRIAL REGISTRATION This trial is registered as ISRCTN07757494, EudraCT 2009-013220-24 and Clinicaltrials.gov NCT00987389. FUNDING This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 38. See the NIHR Journals Library website for further project information.
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Affiliation(s)
- David Jayne
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Michael Walsh
- Department of Nephrology, McMaster University, Hamilton, ON, Canada
| | - Peter A Merkel
- Department of Rheumatology, University of Pennsylvania, Philadelphia, PA, USA
| | - Chen Au Peh
- Royal Adelaide Hospital, Adelaide, SA, Australia
| | - Wladimir Szpirt
- Department of Nephrology, Rigshospitalet, Copenhagen, Denmark
| | - Xavier Puéchal
- National Referral Centre for Rare Systemic Autoimmune Diseases, Cochin Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Shouichi Fujimoto
- Department of Hemovascular Medicine and Artificial Organs, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan
| | - Carmel Hawley
- Department of Nephrology, The University of Queensland, Brisbane, QLD, Australia
| | - Nader Khalidi
- Department of Rheumatology, McMaster University, Hamilton, ON, Canada
| | - Rachel Jones
- Renal Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Ron Wald
- Department of Rheumatology, St Michael's Hospital, Toronto, ON, Canada
| | - Louis Girard
- Department of Nephrology, University of Calgary, Calgary, AB, Canada
| | - Adeera Levin
- Department of Nephrology, St Paul's Hospital, Vancouver, BC, Canada
| | - Gina Gregorini
- Department of Nephrology, Azienda Ospedaliera Spedali Civili di Brescia, Brescia, Italy
| | - Lorraine Harper
- Department of Nephrology, University of Birmingham, Birmingham, UK
| | - William Clark
- Department of Nephrology, University of Western Ontario, London, ON, Canada
| | - Christian Pagnoux
- Department of Rheumatology, Mount Sinai Hospital, Toronto, ON, Canada
| | - Ulrich Specks
- Department of Pulmonary Medicine, Mayo Clinic, Rochester, MN, USA
| | - Lucy Smyth
- Department of Nephrology, The Royal Devon and Exeter Hospital, Exeter, UK
| | - Toshiko Ito-Ihara
- Clinical and Translational Research Centre, Kyoto Prefecture University of Medicine, Kyoto, Japan
| | - Janak de Zoysa
- Department of Nephrology, North Shore Hospital, Auckland, New Zealand
| | - Biljana Brezina
- Renal Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Andrea Mazzetti
- The Research Institute, St Joseph's Healthcare, Hamilton, ON, Canada
| | - Carol A McAlear
- Department of Rheumatology, University of Pennsylvania, Philadelphia, PA, USA
| | - Donna Reidlinger
- Australasian Kidney Trials Network, The University of Queensland, Brisbane, QLD, Australia
| | - Samir Mehta
- Birmingham Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | - Natalie Ives
- Birmingham Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | | | - Hugh Jarrett
- Birmingham Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | - Keith Wheatley
- Cancer Research UK Clinical Trials Unit, University of Birmingham, Birmingham, UK
| | | | - Alina Casian
- Department of Medicine, University of Cambridge, Cambridge, UK
| | - Charles D Pusey
- Department of Nephrology, Imperial College London, London, UK
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11
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Wright JR, Deen QFE, Stevenson A, Telford-Cooke LL, Parker C, Martin-Ruiz C, Steinert JR, Kalaria RN, Mukaetova-Ladinska EB. Plasma Myeloperoxidase as a Potential Biomarker of Patient Response to Anti-Dementia Treatment in Alzheimer's Disease. J Alzheimers Dis 2022; 89:1483-1492. [PMID: 36057826 DOI: 10.3233/jad-220642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Myeloperoxidase (MPO), a neutrophil-derived pro-inflammatory protein, co-localizes with amyloid-β (Aβ) plaques in Alzheimer's disease (AD). Anti-dementia treatment may facilitate efflux of Aβ and associated plaque proteins from the brain to the peripheral circulation, therefore providing potential biomarkers for the monitoring of donor response to drug treatment. OBJECTIVE We investigated the diagnostic utility of MPO as a biomarker of AD, and how anti-dementia treatment alters plasma MPO concentration. METHODS Thirty-two AD patients were recruited, and plasma collected pre-drug administration (baseline), and 1- and 6-months post-treatment. All patients received cholinesterase inhibitors (ChEIs). At baseline and 6 months, patients underwent neuropsychological assessment. Forty-nine elderly healthy individuals with normal cognitive status served as controls. Plasma MPO concentration was measured by ELISA. RESULTS AD drug naïve patients had similar plasma MPO concentration to their control counterparts (p > 0.05). Baseline MPO levels positively correlated with Neuropsychiatric Inventory score (r = 0.5080; p = 0.011) and carer distress (r = 0.5022; p = 0.012). Following 1-month ChEI treatment, 84.4% of AD patients exhibited increased plasma MPO levels (p < 0.001), which decreased at 6 months (p < 0.001). MPO concentration at 1 month was greatest in AD patients whose memory deteriorated during the study period (p = 0.028), and for AD patients with deterioration in Cornell assessment score (p = 0.044). CONCLUSION Whereas baseline MPO levels did not differentiate between healthy and AD populations, baseline MPO positively correlated with initial Neuropsychiatric Inventory evaluation. Post-treatment, transient MPO upregulation in ChEI-treated patients may reflect worse therapeutic outcome. Further studies are required to assess the potential of plasma MPO as an AD therapeutic biomarker.
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Affiliation(s)
- Joy R Wright
- Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, UK
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Quazi Fahm E Deen
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Anna Stevenson
- School of Life Sciences, University of Glasgow, Glasgow, UK
| | | | - Craig Parker
- BioScreening Core Facility-CAV, Newcastle University, Newcastle, UK
| | | | - Joern R Steinert
- Division of Physiology, Pharmacology and Neuroscience, University of Nottingham, UK
| | - Raj N Kalaria
- Translational and Clinical Research Institute, Newcastle University, Newcastle, UK
| | - Elizabeta B Mukaetova-Ladinska
- Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, UK
- The Evington Centre, Leicester General Hospital, Leicester, UK
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12
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Durmaz D, Anbarcioglu B, Bulut M, Erdogan B, Celik E, Akoglu H. The Critical Role of Therapeutic Plasma Exchange in the Treatment of MPO-ANCA Associated Crescentic IgA Nephropathy. Iran J Kidney Dis 2022; 1:63-65. [PMID: 35271501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 08/25/2021] [Indexed: 06/14/2023]
Abstract
Crescentic IgA nephropathy (IgAN) with the positivity for antineutrophilic cytoplasmic antibody (ANCA) is a novel and uncommon entity. The optimal management of this condition is not well-defined. We report a 49-years-old woman with complaints of skin rash and swelling of lower limbs. She had hematuria, proteinuria and, progressive renal impairment with positive myeloperoxidase (MPO)-ANCA test. A renal biopsy revealed MPO-ANCA-associated crescentic IgAN. Induction therapy was intravenous methylprednisolone, cyclophosphamide and, therapeutic plasma exchange (TPE). An unexpected disease flare-up was observed during induction immunosuppressive therapy which regressed after long-term TPE. The patient experienced a full renal recovery after treatment with long-term TPE, cyclophosphamide, and corticosteroids. DOI: 10.52547/ijkd.6490.
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Affiliation(s)
| | | | | | | | | | - Hadim Akoglu
- Department of Nephrology, Gulhane Training and Research Hospital, University of Health Sciences, Ankara, Turkey.
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13
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Koening CL, von Hennigs I. Antineutrophil cytoplasmic antibody (ANCA) vasculitis: pathophysiology, diagnosis, and the evolving treatment landscape. Am J Manag Care 2021; 27:S267-S276. [PMID: 34473462 DOI: 10.37765/ajmc.2021.88746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The antineutrophil cytoplasmic antibody (ANCA) vasculitides include several closely related, often severe, multisystem autoimmune diseases characterized by antibodies against serine proteinase 3 (PR3) or myeloperoxidase. Loss of tolerance to these antigens triggers a cascade of events, beginning with the priming of neutrophils by proinflammatory cytokines and complement activation, translocation of ANCA-specific antigens to the plasma membrane, neutrophil hyperactivation, and further activation of the alternative complement pathway, leading to tissue damage and the clinical manifestations of ANCA vasculitis. Due to the heterogeneity in presentation of these diseases, diagnosis is often substantially delayed, leading to poor outcomes. The current treatment pathway for most patients involves induction with cyclophosphamide or rituximab in combination with glucocorticoids, followed by a maintenance phase with rituximab, azathioprine, or methotrexate, during which time glucocorticoids are tapered. Current therapies are often effective in inducing and maintaining remission but are associated with a range of toxicities. Several new therapies are in development for ANCA vasculitis. Avacopan, an orally administered inhibitor of the complement fragment 5a (C5a) receptor, has been assessed in a phase 3 clinical trial and may play a role in reducing the cumulative glucocorticoid dose. Preliminary data suggest that cluster of differentiation (CD) 80 and CD86 blockade with abatacept may also have a role in the management of ANCA vasculitis. There is an unmet need for additional therapeutic options for patients with these diseases.
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Affiliation(s)
- Curry L Koening
- University of Utah, Division of Rheumatology, c/o Curry Koening, 30 N 1900 E, Salt Lake City, UT 84132.
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Wang H, Li P, Yu D, Zhang Y, Wang Z, Liu C, Qiu H, Liu Z, Ren J, Qu X. Unraveling the Enzymatic Activity of Oxygenated Carbon Nanotubes and Their Application in the Treatment of Bacterial Infections. Nano Lett 2018; 18:3344-3351. [PMID: 29763562 DOI: 10.1021/acs.nanolett.7b05095] [Citation(s) in RCA: 123] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Carbon nanotubes (CNTs) and their derivatives have emerged as a series of efficient biocatalysts to mimic the function of natural enzymes in recent years. However, the unsatisfiable enzymatic efficiency usually limits their practical usage ranging from materials science to biotechnology. Here, for the first time, we present the synthesis of several oxygenated-group-enriched carbon nanotubes (o-CNTs) via a facile but green approach, as well as their usage as high-performance peroxidase mimics for biocatalytic reaction. Exhaustive characterizations of the enzymatic activity of o-CNTs have been provided by exploring the accurate effect of various oxygenated groups on their surface including carbonyl, carboxyl, and hydroxyl groups. Because of the "competitive inhibition" effect among all of these oxygenated groups, the catalytic efficiency of o-CNTs is significantly enhanced by weakening the presence of noncatalytic sites. Furthermore, the admirable enzymatic activity of these o-CNTs has been successfully applied in the treatment of bacterial infections, and the results of both in vitro and in vivo nanozyme-mediated bacterial clearance clearly demonstrate the feasibility of o-CNTs as robust peroxidase mimics to effectively decrease the bacterial viability under physiological conditions. We believe that the present study will not only facilitate the construction of novel efficient nanozymes by rationally adjusting the degree of the "competitive inhibition" effect, but also broaden the biological usage of o-CNT-based nanomaterials via their satisfactory enzymatic activity.
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Affiliation(s)
- Huan Wang
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- University of Science and Technology of China , Hefei 230029 , P. R. China
| | - Penghui Li
- MOE Key Laboratory of Green Chemistry, College of Chemistry , Sichuan University , Chengdu 610064 , P. R. China
| | - Dongqin Yu
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- University of Science and Technology of China , Hefei 230029 , P. R. China
| | - Yan Zhang
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- Graduate School of the Chinese Academy of Sciences , Beijing 100039 , P. R. China
| | - Zhenzhen Wang
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- Graduate School of the Chinese Academy of Sciences , Beijing 100039 , P. R. China
| | - Chaoqun Liu
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- Graduate School of the Chinese Academy of Sciences , Beijing 100039 , P. R. China
| | - Hao Qiu
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
- University of Science and Technology of China , Hefei 230029 , P. R. China
| | - Zhen Liu
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
| | - Jinsong Ren
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
| | - Xiaogang Qu
- State Key Laboratory of Rare Earth Resources Utilization and Laboratory of Chemical Biology , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , P. R. China
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15
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Dai Y, Cheng S, Wang Z, Zhang R, Yang Z, Wang J, Yung BC, Wang Z, Jacobson O, Xu C, Ni Q, Yu G, Zhou Z, Chen X. Hypochlorous Acid Promoted Platinum Drug Chemotherapy by Myeloperoxidase-Encapsulated Therapeutic Metal Phenolic Nanoparticles. ACS Nano 2018; 12:455-463. [PMID: 29293312 DOI: 10.1021/acsnano.7b06852] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
This study applies in situ production of hypochlorous acid (HOCl) to improve the therapeutic efficacy of platinum drugs. The phagocytic enzyme myeloperoxidase (MPO) is coated with two functional polyphenol derivatives (platinum prodrug polyphenols and PEG polyphenols) and ferric ion by metal phenolic coordination, which can shield MPO from degradation by other compounds in the blood. Moreover, the platinum prodrug can be reduced to cisplatin in cells and produce hydrogen peroxide (H2O2). The MPO catalyzes the conversion of H2O2 to HOCl in the intercellular environment. The as-prepared MPO Pt PEG nanoparticles (MPP NPs) can be employed as a reactive oxygen species cascade bioreaction to enhance platinum drug therapy. The MPP NPs show prolonged blood circulation and high tumor accumulation as evidenced by 89Zr-based positron emission tomography imaging. The MPP NPs effectively inhibit tumor growth in vivo. As a first-in-class platform to harness the highly toxic HOCl in nanomedicine for cancer therapy, this strategy may open doors for further development of progressive therapeutic systems.
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Affiliation(s)
- Yunlu Dai
- Engineering Research Center of Molecular-imaging and Neuro-imaging of Ministry of Education, School of Life Science and Technology, Xidian University , Xi'an, Shaanxi 710126, China
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Siyuan Cheng
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Zhongliang Wang
- Engineering Research Center of Molecular-imaging and Neuro-imaging of Ministry of Education, School of Life Science and Technology, Xidian University , Xi'an, Shaanxi 710126, China
| | - Ruili Zhang
- Engineering Research Center of Molecular-imaging and Neuro-imaging of Ministry of Education, School of Life Science and Technology, Xidian University , Xi'an, Shaanxi 710126, China
| | - Zhen Yang
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Jingjing Wang
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Bryant C Yung
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Zhantong Wang
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Orit Jacobson
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Can Xu
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Qianqian Ni
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Guocan Yu
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Zijian Zhou
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
| | - Xiaoyuan Chen
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH) , Bethesda, Maryland 20892, United States
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16
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Stark J, Varga Z, Ghidán Á, Vajdovich P, Szombath D, Marczell I, Várbíró S, Dinya E, Magyar T, Tulassay Z, Székács B, Nagy K, Rácz K, Békési G. The effect of indomethacin, myeloperoxidase, and certain steroid hormones on bactericidal activity: an ex vivo and in vivo experimental study. Ann Clin Microbiol Antimicrob 2014; 13:27. [PMID: 25001579 PMCID: PMC4105879 DOI: 10.1186/1476-0711-13-27] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 06/28/2014] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The role of myeloperoxidase (MPO) is essential in the killing of phagocytosed bacteria. Certain steroid hormones increase MPO plasma concentration. Our aim was to test the effect of MPO, its inhibitor indomethacin, and certain steroid hormones on bactericidal activity. METHODS Human polymorphonuclear leukocytes (PMN) were incubated with opsonised Escherichia coli and either MPO, indomethacin, estradiol, or hydrocortisone. Intracellular killing capacity was evaluated with UV microscopy after treatment with fluorescent dye. Next, an in vivo experiment was performed with nine groups of rats: in the first phase of the study indomethacin treatment and Pasteurella multocida infection (Ii), indomethacin treatment without infection (I0), untreated control with infection (Mi) and untreated control without infection (M0); in the second phase of the study rats with infection and testosterone treatment (NT), castration, infection and testosterone treatment (CT), castration, infection and estradiol treatment (CE), non-castrated infected control (N0), and castrated infected control (C0). After treatment bacteria were reisolated from the liver and heart blood on agar plates, and laboratory parameters were analyzed. For the comparison of laboratory results ANOVA or Kruskal-Wallis test and LSD post hoc test was used. RESULTS Indomethacin did not have a remarkable effect on the bacterial killing of PMNs, while the other compounds increased bacterial killing to various degrees. In the animal model indomethacin and infection caused a poor clinical state, a great number of reisolated bacteria, elevated white blood cell (WBC) count, decreased C-reactive protein (CRP) and serum albumin levels. Testosterone treatment resulted in less bacterial colony numbers in group NT, but not in group CT compared to respective controls (N0, C0). Estradiol treatment (CE) decreased colony numbers compared to control (C0). Hormone administration resulted in lower WBC counts, and in group CE, a decreased CRP. CONCLUSIONS MPO, estradiol, and hydrocortisone improve bacterial killing activity of PMNs. Indomethacin treatment and castration weaken immune responses and clinical state of infected rats, while testosterone and estradiol have a beneficial effect.
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Affiliation(s)
- Júlia Stark
- Faculty of Medicine, 2nd Department of Internal Medicine, Semmelweis University, 46. Szentkiralyi u., H-1088 Budapest, Hungary
| | - Zsuzsanna Varga
- Hungarian Academy of Sciences, Institute for Veterinary Medical Research, 21. Hungaria krt., H-1143 Budapest, Hungary
| | - Ágoston Ghidán
- Faculty of Medicine, Institute of Medical Microbiology, Semmelweis University, 4. Nagyvarad ter, H-1089 Budapest, Hungary
| | - Péter Vajdovich
- Department and Clinic of Internal Medicine, Szent Istvan University, Faculty of Veterinary Science, 2. Istvan u., H-1078 Budapest, Hungary
| | - Dezső Szombath
- Faculty of Medicine, Institute of Patophysiology, Semmelweis University, 4. Nagyvarad ter, H-1089 Budapest, Hungary
| | - István Marczell
- Faculty of Medicine, 2nd Department of Internal Medicine, Semmelweis University, 46. Szentkiralyi u., H-1088 Budapest, Hungary
| | - Szabolcs Várbíró
- Faculty of Medicine, 2nd Department of Obstetrics and Gynecology, Semmelweis University, 78/a Ulloi ut, H-1082 Budapest, Hungary
| | - Elek Dinya
- Faculty of Health and Public Services, Institute of Health Informatics Development and Further Training, Semmelweis University, 78/b Ulloi ut, H-1082 Budapest, Hungary
| | - Tibor Magyar
- Hungarian Academy of Sciences, Institute for Veterinary Medical Research, 21. Hungaria krt., H-1143 Budapest, Hungary
| | - Zsolt Tulassay
- Faculty of Medicine, 2nd Department of Internal Medicine, Semmelweis University, 46. Szentkiralyi u., H-1088 Budapest, Hungary
| | - Béla Székács
- Faculty of Medicine, 2nd Department of Internal Medicine, Semmelweis University, 46. Szentkiralyi u., H-1088 Budapest, Hungary
| | - Károly Nagy
- Faculty of Medicine, Institute of Medical Microbiology, Semmelweis University, 4. Nagyvarad ter, H-1089 Budapest, Hungary
| | - Károly Rácz
- Faculty of Medicine, 2nd Department of Internal Medicine, Semmelweis University, 46. Szentkiralyi u., H-1088 Budapest, Hungary
| | - Gábor Békési
- Faculty of Medicine, 2nd Department of Internal Medicine, Semmelweis University, 46. Szentkiralyi u., H-1088 Budapest, Hungary
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17
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Abstract
To observe the effects of peroxidase on hyperlipidemia, mice were fed a diet high in cholesterol and fat. At the same time, the mice were given different-purity peroxidase (radish juice, crude radish peroxidase, and horseradish peroxidase), and their serum cholesterol, triglyceride, blood glucose, amylase, and esterase activities, and malondialdehyde in the mouse small intestines and livers, were tested after 15 days on the test diets. The results showed that peroxidase decreased the levels of total serum cholesterol, triglyceride, blood glucose, and lipid peroxidation in the small intestines and livers of hyperlipidemic mice. This suggests that peroxidase may be a contributing factor in the prevention of hyperlipidemia.
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Affiliation(s)
- Linsong Wang
- Life Science College, Henan Normal University, Xinxiang, Henan, (453002), People's Republic of China.
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18
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Maslov AK, Kalyanina OV. Effect of peroxidase on the development of experimental leprosy in mice after intraplantar infection. Bull Exp Biol Med 2000; 129:484-6. [PMID: 10977959 DOI: 10.1007/bf02439810] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/1999] [Indexed: 10/24/2022]
Abstract
Lyophilized horseradish peroxidase (activity 100 U/mg) administered per os in a dose of 100-200 mg/kg fodder enhanced bactericidal activity of phagocytes in mice experimentally infected with Mycobacterium leprae, which manifested in suppression of M. leprae growth in comparison with untreated controls.
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Affiliation(s)
- A K Maslov
- Institute of Leprosy, Ministry of Health of Russian Federation, Astrakhan
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19
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Tournay C, Courtoy PJ, Marodi L, Totté P, Werenne J, Jacquet A, Garcia-Quintana L, Bollen A, Moguilevsky N. Uptake of recombinant myeloperoxidase, free or fused to Fc gamma, by macrophages enhances killing activity toward micro-organisms. DNA Cell Biol 1996; 15:617-24. [PMID: 8769563 DOI: 10.1089/dna.1996.15.617] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
A chimeric antibody-like molecule consisting of the human myeloperoxidase (rMPO) fused to the second and third constant-sequence (CH2 and CH3) Fc domains of human immunoglobulin G-1 has been constructed and expressed in Chinese hamster ovary (CHO) cells. This fusion molecule was designed to combine the binding specificity of Fc with the antimicrobial properties of rMPO. The rMPO-Fc fusion dimerized through the Fc fragment, while retaining the enzymatic activity of rMPO. The chimeric molecule was glycosylated and most of the propeptide was eliminated, indicating a better processing of the polypeptide than for rMPO alone. Both rMPO and rMPO-Fc bound to and were internalized by macrophage-like U937 promonocytic cells. Unexpectedly, the chimera failed to bind to the Fc receptor but interacted with a higher affinity than rMPO with the same binding sites. The presence of the Fc fragment in the chimera, in addition, did not extend the plasma half-life of the fusion protein. In vitro, rMPO-Fc exhibited a stronger killing effect than rMPO toward Candida albicans in the presence of either H202 alone or human macrophages. In vivo, rMPO-Fc similarly conferred a better protection than rMPO in a lethal model of murine cowdriosis. These properties could be related to the Fc-induced dimerization of the fusion protein in CHO cells.
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Affiliation(s)
- C Tournay
- Applied Genetics, University of Brussels, Nivelles, Belgium
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20
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Bernard M, Menasché P, Piétri S, Grousset C, Piwnica A, Cozzone PJ. Cardioplegic arrest superimposed on evolving myocardial ischemia. Improved recovery after inhibition of hydroxyl radical generation by peroxidase or deferoxamine. A 31P nuclear resonance study. Circulation 1988; 78:III164-72. [PMID: 2846203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Superimposition of cardioplegic arrest on acute low-cardiac-output states, as may occur after failure of percutaneous transluminal coronary angioplasty requiring emergency surgery, is associated with an increased operative risk. This increased risk is possibly attributable to reperfusion, which, after sequential episodes of myocardial ischemia, exacerbates tissue injury mediated by oxygen free radicals. One of the most cytotoxic of these active oxygen species is the hydroxyl radical, which is formed from superoxide anion and hydrogen peroxide through an iron-catalyzed reaction. This study assesses the effects of peroxidase, a hydrogen-peroxide scavenger, and of deferoxamine, an iron chelator, in isolated working rat hearts subjected to 30 minutes of low-flow ischemia (75% reduction in coronary flow) followed by 2 hours of cardioplegic arrest at 15 degrees C and by 30 minutes of normothermic reperfusion. Three groups of hearts (n = 7) were studied. Two groups were pretreated with either peroxidase (10,000 units/l) or deferoxamine (0.03 mM) during the last 15 minutes of the low-flow ischemic period. The third group received no prearrest intervention and served as a control group. In addition to hemodynamic determination, high-energy phosphate content [adenosine 5'-triphosphate (ATP)] and intracellular pH were monitored serially by 31P nuclear magnetic resonance spectroscopy. The two pretreated groups had better recovery of ATP levels and aortic flow values than did the control group.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M Bernard
- Centre de Résonance Magnétique Biologique et Médicale, Faculté de Médecine, Université d'Aix Marseille, France
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