1
|
Tian X, Ji X, Zhang R, Long X, Lin J, Zhang Y, Zhan L, Luan J, Zhao G, Peng X. Therapeutic effect of oxidized bletilla striata polysaccharide-natamycin eye drops on fungal keratitis. J Biomater Appl 2024:8853282241280844. [PMID: 39208309 DOI: 10.1177/08853282241280844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
OBJECTIVE Fungal keratitis (FK) usually develops to a poor clinical prognosis due to the fungal invasion and excessive inflammatory reaction. In order to enhance the therapeutic effect of natamycin (NAT), we used the anti-inflammatory biological polysaccharide bletilla striata polysaccharide (BSP) combined with NAT to prepare a new eye drop -- oxidized bletilla striata polysaccharide-natamycin (OBN). METHODS UV-vis, FT-IR, and fluorescence spectroscopy were used to identify the synthesis of OBN. Biocompatibility of OBN was determined by CCK-8, scratch assay, and corneal toxicity test. RAW264.7 cells and C57BL/6 mice were stimulated with A. fumigatus and treated with PBS, OBN, or NAT. The anti-inflammatory activity of OBN was detected by RT-PCR and ELISA. In mice with FK, the clinical scores were used to evaluate the effect of OBN; HE staining was performed to assess the corneal pathological changes; MPO assay and immunofluorescence staining were used to investigate neutrophil infiltration. RESULTS OBN was synthesized by combining oxidized bletilla striata polysaccharide (OBSP) with NAT through Schiff base reaction. OBN did not affect cell viability at a concentration of 160 μg/mL in HCECs, RAW264.7 cells, and mouse corneas. OBN versus NAT significantly improved the prognosis of A. fumigatus keratitis by reducing disease severity, neutrophil infiltration, and expression of inflammatory factors in vivo. Additionally, OBN treatment down-regulated the mRNA and protein expression levels of inflammatory factors IL-1β, TNF-α, and IL-6 in RAW264.7 and mouse models. CONCLUSION OBN is a compound prepared by covalently linking OBSP to the imino group of NAT through Schiff base reaction. OBN treatment down-regulated inflammation and improved the prognosis of mice with A. fumigatus keratitis.
Collapse
Affiliation(s)
- Xue Tian
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xiaoyue Ji
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Ranran Zhang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Xiaojing Long
- State Key Laboratory of Bio-fibers and Eco-textiles, Institute of Marine Biobased Materials, College of Materials Science and Engineering, Qingdao University, Qingdao, China
| | - Jing Lin
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yingxue Zhang
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Lu Zhan
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Junjie Luan
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Guiqiu Zhao
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xudong Peng
- Department of Ophthalmology, University of Washington, Seattle, WA, USA
| |
Collapse
|
2
|
Li J, Xu X. Immune Checkpoint Inhibitor-Based Combination Therapy for Colorectal Cancer: An Overview. Int J Gen Med 2023; 16:1527-1540. [PMID: 37131870 PMCID: PMC10149070 DOI: 10.2147/ijgm.s408349] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 04/19/2023] [Indexed: 05/04/2023] Open
Abstract
Colorectal cancer (CRC) is one of the most common diseases in the world. Tumor immunotherapy is an innovative cancer treatment that acts by activating the human body's autoimmune system. Immune checkpoint block has been shown to be effective in DNA deficient mismatch repair/microsatellite instability-high CRC. However, the therapeutic effect for proficient mismatch repair/microsatellite stability patients still requires further study and optimization. At present, the main CRC strategy is to combine other therapeutic methods, such as chemotherapy, targeted therapy, and radiotherapy. Here, we review the current status and the latest progress of immune checkpoint inhibitors in the treatment of CRC. At the same time, we consider therapeutic opportunities for transforming cold to hot, as well as perspectives on possible future therapies, which may be in great demand for drug-resistant patients.
Collapse
Affiliation(s)
- Jingjing Li
- Department of Gastroenterology, Shidong Hospital of Shanghai, Shanghai, People’s Republic of China
| | - Xuanfu Xu
- Department of Gastroenterology, Shidong Hospital of Shanghai, Shanghai, People’s Republic of China
- Correspondence: Xuanfu Xu, Department of Gastroenterology, Shidong Hospital of Shanghai, Shanghai, People’s Republic of China, Tel +86-021-25066666, Email
| |
Collapse
|
3
|
Arunachalam D, Ramanathan SM, Menon A, Madhav L, Ramaswamy G, Namperumalsamy VP, Prajna L, Kuppamuthu D. Expression of immune response genes in human corneal epithelial cells interacting with Aspergillus flavus conidia. BMC Genomics 2022; 23:5. [PMID: 34983375 PMCID: PMC8728928 DOI: 10.1186/s12864-021-08218-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 11/18/2021] [Indexed: 12/19/2022] Open
Abstract
Background Aspergillus flavus, one of the causative agents of human fungal keratitis, can be phagocytosed by human corneal epithelial (HCE) cells and the conidia containing phagosomes mature into phagolysosomes. But the immunological responses of human corneal epithelial cells interacting with A. flavus are not clear. In this study, we report the expression of immune response related genes of HCE cells exposed to A. flavus spores using targeted transcriptomics. Methods Human corneal epithelial cell line and primary cultures were grown in a six-well plate and used for coculture experiments. Internalization of the conidia was confirmed by immunofluorescence microscopy of the colocalized endosomal markers CD71 and LAMP1. Total RNA was isolated, and the quantity and quality of the isolated RNA were assessed using Qubit and Bioanalyzer. NanoString nCounter platform was used for the analysis of mRNA abundance using the Human Immunology panel. R-package and nSolver software were used for data analysis. KEGG and FunRich 3.1.3 tools were used to analyze the differentially expressed genes. Results Different morphotypes of conidia were observed after 6 h of coculture with human corneal epithelial cells and found to be internalized by epithelial cells. NanoString profiling showed more than 20 differentially expressed genes in immortalized human corneal epithelial cell line and more than ten differentially expressed genes in primary corneal epithelial cells. Distinct set of genes were altered in their expression in cell line and primary corneal epithelial cells. KEGG pathway analysis revealed that genes associated with TNF signaling, NF-KB signaling, and Th17 signaling were up-regulated, and genes associated with chemokine signaling and B cell receptor signaling were down regulated. FunRich pathway analysis showed that pathways such as CDC42 signaling, PI3K signaling, and Arf6 trafficking events were activated by the clinical isolates CI1123 and CI1698 in both type of cells. Conclusions Combining the transcript analysis data from cell lines and primary cultures, we showed the up regulation of immune defense genes in A. flavus infected cells. At the same time, chemokine signaling and B cell signaling pathways are downregulated. The variability in the expression levels in the immortalized cell line and the primary cultures is likely due to the variable epigenetic reprogramming in the immortalized cells and primary cultures in the absence of any changes in the genome. It highlights the importance of using both cell types in host-pathogen interaction studies. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-08218-5.
Collapse
Affiliation(s)
- Divya Arunachalam
- Proteomics Department, Aravind Medical Research Foundation, Dr. G. Venkataswamy Eye Research Institute, Aravind Eye Care System, Madurai, Tamil Nadu, India.,Department of Biotechnology, Alagappa University, Karaikudi, Tamil Nadu, India
| | - Shruthi Mahalakshmi Ramanathan
- Proteomics Department, Aravind Medical Research Foundation, Dr. G. Venkataswamy Eye Research Institute, Aravind Eye Care System, Madurai, Tamil Nadu, India
| | - Athul Menon
- Theracues Innovations Private Limited, Bangalore, India, Karnataka
| | - Lekshmi Madhav
- Theracues Innovations Private Limited, Bangalore, India, Karnataka
| | | | | | - Lalitha Prajna
- Department of Ocular Microbiology, Aravind Eye Hospital, Aravind Eye Care System, Madurai, Tamil Nadu, India
| | - Dharmalingam Kuppamuthu
- Proteomics Department, Aravind Medical Research Foundation, Dr. G. Venkataswamy Eye Research Institute, Aravind Eye Care System, Madurai, Tamil Nadu, India. .,Department of Biotechnology, Alagappa University, Karaikudi, Tamil Nadu, India. .,Aravind Medical Research Foundation, Dr. G.Venkataswamy Eye Research Institute, Aravind Eye Care System, No.1 Anna Nagar, Madurai, Tamil Nadu, India.
| |
Collapse
|
4
|
Liu Y, Li Z, Wang S, Zhang C, Han L, Sun Q, Han X. Aspergillus fumigatus Induces the Release of IL-8 and MCP-1 by Activating Nuclear Transcription Through Dectin-1 and CR3 Receptors in Alveolar Epithelial Cells. Curr Microbiol 2021; 78:3474-3482. [PMID: 34272600 DOI: 10.1007/s00284-021-02534-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/03/2021] [Indexed: 01/18/2023]
Abstract
Invasive pulmonary aspergillosis induced by the pathogenic fungus Aspergillus fumigatus is one of the common fatal complications in immunocompromised patients. Lung epithelial cells play an important role in host immune defense against A. fumigatus. However, the interaction between lung epithelial cells and A. fumigatus conidia is not fully understood. In this study, we used the swollen conidia of A. fumigatus to stimulate the type II lung epithelial A549 cells. Results showed that swollen conidia could significantly increase RNA transcription and protein expression of interleukin 8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1), but not TNF-α in A549 cells in a time-dependent manner. Moreover, serum opsonization was able to improve the release of inflammatory factors induced by swollen conidia. Blocking of the dectin-1 or CR3 receptors, or both simultaneously, in the A549 cells could decrease the release of IL-8 and MCP-1. Additionally, blocking dectin-1 or CR3 could inhibit the transcription of nuclear factor NF-κB that was activated by swollen conidia. Here we reported for the first time that dectin-1 and CR3 receptors in A549 cells mediate the release of pro-inflammatory factors IL-8 and MCP-1 induced by A. fumigatus.
Collapse
Affiliation(s)
- Yanxi Liu
- Key Laboratory of Bio-Resources and Eco-Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, China.,Department of Hospital Infection Control and Research, Institute of Disease Control and Prevention of PLA, Beijing, China.,Department of Clinical Laboratory of The 907 Hospital of PLA, Fujian, China
| | - Zhiqian Li
- Department of Hospital Infection Control and Research, Institute of Disease Control and Prevention of PLA, Beijing, China.,Department of Clinical Laboratory of The 907 Hospital of PLA, Fujian, China
| | - Shuo Wang
- Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Qinghai, China.,Qinghai Provincial Key Laboratory of Tibetan Medicine Research, Qinghai, China
| | - Changjian Zhang
- Department of Hospital Infection Control and Research, Institute of Disease Control and Prevention of PLA, Beijing, China
| | - Li Han
- Department of Hospital Infection Control and Research, Institute of Disease Control and Prevention of PLA, Beijing, China
| | - Qun Sun
- Key Laboratory of Bio-Resources and Eco-Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, Sichuan, China.
| | - Xuelin Han
- Department of Hospital Infection Control and Research, Institute of Disease Control and Prevention of PLA, Beijing, China.
| |
Collapse
|
5
|
Zhang R, Peng X, Lin J, Zhang Y, Zhan L, Tian X, Yin J, Zhao G. The Role of SREC-Ⅰ in Innate Immunity to Aspergillus fumigatus Keratitis. Invest Ophthalmol Vis Sci 2021; 62:12. [PMID: 34236384 PMCID: PMC8267217 DOI: 10.1167/iovs.62.9.12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Purpose To determine the role of scavenger receptor expressed by endothelial cell-1 (SREC-Ⅰ) in vitro and in a mouse model of Aspergillus fumigatus keratitis. Methods SREC-Ⅰ mRNA and protein expression were tested in both normal and A fumigatus stimulated human corneal epithelial cells (HCECs). Immunofluorescence was used to detect SREC-Ⅰ expression in human corneas with or without A fumigatus infection. HCECs were incubated with SREC-Ⅰ small interfering RNA, then the mRNA levels of LOX-1, IL-1β, and TNF-α were detected after A fumigatus stimulation. A mouse fungal keratitis (FK) model was established and SREC-Ⅰ mRNA and protein expression were detected by RT-PCR, Western blot and immunofluorescence. The severity of FK was evaluated by clinical score. CLCX1, LOX-1, IL-1β, and TNF-α mRNA expression levels were tested before and after anti-SREC-Ⅰ treatment. Results SREC-Ⅰ expressed in normal and A fumigatus treated HCECs and human corneal epithelium. In vitro experiment showed that SREC-Ⅰ mRNA and protein levels were significantly increased after A fumigatus stimulation. SREC-Ⅰ small interfering RNA treatment inhibited the expressions of LOX-1, IL-1β, and TNF-α in HCECs. The expressions of CLCX1, LOX-1, IL-1β, and TNF-α were elevated in mice with A fumigatus keratitis, which could be decreased by SREC-Ⅰ-neutralizing antibody treatment. Conclusions SREC-Ⅰ is a key mediator in inflammatory response induced by A fumigatus keratitis. SREC-Ⅰ blockade could be a potential therapeutic approach for FK.
Collapse
Affiliation(s)
- Ranran Zhang
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Xudong Peng
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Jing Lin
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Yingxue Zhang
- Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Lu Zhan
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Xue Tian
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Jiao Yin
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Guiqiu Zhao
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| |
Collapse
|
6
|
Human Corneal Epithelial Cells Internalize Aspergillus flavus Spores by Actin-Mediated Endocytosis. Infect Immun 2021; 89:IAI.00794-20. [PMID: 33753415 DOI: 10.1128/iai.00794-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 03/03/2021] [Indexed: 01/09/2023] Open
Abstract
Human corneal epithelial (HCE) cells play a significant role in the innate immune response by secreting cytokines and antimicrobial peptides when they encounter fungal pathogens. But the detailed mechanism of attachment and engulfment of the fungal conidia by HCE cells is not well understood. Here, we show the phagocytosis of Aspergillus flavus conidia by RCB2280 cells and primary HCE cultures using confocal microscopy and proteomic analysis of conidium-containing phagosomes. Phalloidin staining showed actin polymerization, leading to an actin ring around engulfed conidia. Cytochalasin D inhibited the actin-mediated endocytosis of the conidia. Immunolabeling of the early endosomal markers CD71 and early endosomal antigen (EEA1) and the late endosomal markers lysosome-associated membrane protein 1 (LAMP1), Rab7, and cathepsin G showed that endosomal proteins were recruited to the site of conidia and showed maturation of the conidium-containing phagosomes. Lysotracker red DND 99 labeling showed the acidification of the phagosomes containing conidia. Phagosome-specific proteome analysis confirmed the recruitment of various phagosomal and endosomal proteins to the conidium-containing phagosomes. These results show that the ocular surface epithelium contributes actively to antifungal defense by the phagocytosis of invading fungal conidia.
Collapse
|
7
|
Tian X, Peng X, Lin J, Zhang Y, Zhan L, Yin J, Zhang R, Zhao G. Isorhamnetin Ameliorates Aspergillus fumigatus Keratitis by Reducing Fungal Load, Inhibiting Pattern-Recognition Receptors and Inflammatory Cytokines. Invest Ophthalmol Vis Sci 2021; 62:38. [PMID: 33783487 PMCID: PMC8010362 DOI: 10.1167/iovs.62.3.38] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Purpose Isorhamnetin is a natural flavonoid with both antimicrobial and anti-inflammatory properties, but its effect on fungal keratitis (FK) remains unknown. The current study aims to investigate the antifungal and anti-inflammatory effects of isorhamnetin against mouse Aspergillus fumigatus keratitis. Methods In vitro, the lowest effective concentration of isorhamnetin was assessed by minimum inhibitory concentration and cytotoxicity tests in human corneal epithelial cells (HCECs) and RAW264.7 cells. The antifungal property was investigated by scanning electron microscopy and propidium iodide uptake test. The anti-inflammatory effect of isorhamnetin in HCECs and RAW264.7 cells was observed by quantitative real-time polymerase chain reaction (qRT-PCR). In the eyes of mice with A. fumigatus keratitis, FK severity was evaluated using clinical score, plate counting, histological staining and periodic acid Schiff staining. In vivo, the anti-inflammatory effect of isorhamnetin was examined by immunofluorescence staining, myeloperoxidase assay, Western blot, enzyme-linked immunosorbent assay, and qRT-PCR. Results In HCECs and RAW264.7 cells, isorhamnetin significantly inhibited A. fumigatus conidia growth and hyphae viability at 80 µg/mL without affecting cell viability. In vitro, isorhamnetin altered A. fumigatus hyphal morphology and membrane integrity. In A. fumigatus keratitis mouse model, isorhamnetin treatment alleviated the severity of FK by reducing corneal fungal load and inhibiting neutrophil recruitment. In addition, the mRNA and protein expression levels of TLR-2, TLR-4, Dectin-1, IL-1β, and tumor necrosis factor-α were significantly decreased in isorhamnetin-treated groups in vivo and in vitro. Conclusions Isorhamnetin improves the prognosis of A. fumigatus keratitis in mice by inhibiting the growth of A. fumigatus, reducing the recruitment of neutrophils and downregulating inflammatory factors.
Collapse
Affiliation(s)
- Xue Tian
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Xudong Peng
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Jing Lin
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Yingxue Zhang
- Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan, United States
| | - Lu Zhan
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Jiao Yin
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Ranran Zhang
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| | - Guiqiu Zhao
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China
| |
Collapse
|
8
|
The sino-nasal warzone: transcriptomic and genomic studies on sino-nasal aspergillosis in dogs. NPJ Biofilms Microbiomes 2020; 6:51. [PMID: 33184275 PMCID: PMC7665010 DOI: 10.1038/s41522-020-00163-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 10/16/2020] [Indexed: 12/21/2022] Open
Abstract
We previously showed that each dog with chronic non-invasive sino-nasal aspergillosis (SNA) was infected with a single genotype of Aspergillus fumigatus. Here, we studied the transcriptome of this fungal pathogen and the canine host within the biofilm resulting from the infection. We describe here transcriptomes resulting from natural infections in animal species with A. fumigatus. The host transcriptome showed high expression of IL-8 and alarmins, uncontrolled inflammatory reaction and dysregulation of the Th17 response. The fungal transcriptome showed in particular expression of genes involved in secondary metabolites and nutrient acquisition. Single-nucleotide polymorphism analysis of fungal isolates from the biofilms showed large genetic variability and changes related with adaptation to host environmental factors. This was accompanied with large phenotypic variability in in vitro stress assays, even between isolates from the same canine patient. Our analysis provides insights in genetic and phenotypic variability of Aspergillus fumigatus in biofilms of naturally infected dogs reflecting in-host adaptation. Absence of a Th17 response and dampening of the Th1 response contributes to the formation of a chronic sino-nasal warzone.
Collapse
|
9
|
Zhan L, Peng X, Lin J, Zhang Y, Gao H, Zhu Y, Huan Y, Zhao G. Honokiol Reduces Fungal Load, Toll-Like Receptor-2, and Inflammatory Cytokines in Aspergillus fumigatus Keratitis. Invest Ophthalmol Vis Sci 2020; 61:48. [PMID: 32347916 PMCID: PMC7401949 DOI: 10.1167/iovs.61.4.48] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Purpose We characterized the effects of Honokiol (HNK) on Aspergillus fumigatus-caused keratomycosis and the underlying mechanisms. HNK is known to have anti-inflammatory and antifungal properties, but the influence on fungal keratitis (FK) remains unknown. Methods In ex vivo, minimum inhibitory concentration and Cell Count Kit-8 assay were carried out spectrophotometrically to provide preferred concentration applied in vivo. Time kill assay pointed that HNK was fungicidal and fungistatic chronologically. Adherence assay, crystal violet staining, and membrane permeability assay tested HNK effects on different fungal stages. In vivo, clinical scores reflected the improvement degree of keratitis outcome. Myeloperoxidase (MPO) assay, flow cytometry (FCM), and immunohistofluorescence staining (IFS) were done to evaluate neutrophil infiltration. Plate count detected HNK fungicidal potentiality. RT-PCR, Western blot, and enzyme-linked immunosorbent assay (ELISA) verified the anti-inflammatory activity of HNK collaboratively. Results In vitro, MIC90 HNK was 8 µg/mL (no cytotoxicity), and Minimal Fungicidal Concentration (MFC) was 12 µg/mL for A. fumigatus. HNK played the fungistatic and fungicidal roles at 6 and 24 hours, respectively, inhibiting adherence at the beginning, diminishing biofilms formation, and increasing membrane permeability all the time. In vivo, HNK improved C57BL/6 mice outcome by reducing disease severity (clinical scores), neutrophil infiltration (MPO, FCM, and IFS), and fungal loading (plate count). RT-PCR, Western blot, and ELISA revealed that HNK downregulated mRNA and protein expression levels of Toll-like receptor-2 (TLR-2), high mobility group box 1 (HMGB1), IL-1β, and TNF-α. Conclusions Our study suggested HNK played antifungal and anti-inflammatory roles on keratomycosis by reducing survival of fungi, infiltration of leucocytes, and expression of HMGB1, TLR-2, and proinflammatory cytokines, providing a potential treatment for FK.
Collapse
|
10
|
Patiño-Medina JA, Reyes-Mares NY, Valle-Maldonado MI, Jácome-Galarza IE, Pérez-Arques C, Nuñez-Anita RE, Campos-García J, Anaya-Martínez V, Ortiz-Alvarado R, Ramírez-Díaz MI, Chan Lee S, Garre V, Meza-Carmen V. Heterotrimeric G-alpha subunits Gpa11 and Gpa12 define a transduction pathway that control spore size and virulence in Mucor circinelloides. PLoS One 2019; 14:e0226682. [PMID: 31887194 PMCID: PMC6936849 DOI: 10.1371/journal.pone.0226682] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 12/03/2019] [Indexed: 02/07/2023] Open
Abstract
Mucor circinelloides is one of the causal agents of mucormycosis, an emerging and high mortality rate fungal infection produced by asexual spores (sporangiospores) of fungi that belong to the order Mucorales. M. circinelloides has served as a model genetic system to understand the virulence mechanism of this infection. Although the G-protein signaling cascade plays crucial roles in virulence in many pathogenic fungi, its roles in Mucorales are yet to be elucidated. Previous study found that sporangiospore size and calcineurin are related to the virulence in Mucor, in which larger spores are more virulent in an animal mucormycosis model and loss of a calcineurin A catalytic subunit CnaA results in larger spore production and virulent phenotype. The M. circinelloides genome is known to harbor twelve gpa (gpa1 to gpa12) encoding G-protein alpha subunits and the transcripts of the gpa11 and gpa12 comprise nearly 72% of all twelve gpa genes transcript in spores. In this study we demonstrated that loss of function of Gpa11 and Gpa12 led to larger spore size associated with reduced activation of the calcineurin pathway. Interestingly, we found lower levels of the cnaA mRNAs in sporangiospores from the Δgpa12 and double Δgpa11/Δgpa12 mutant strains compared to wild-type and the ΔcnaA mutant had significantly lower gpa11 and gpa12 mRNA levels compared to wild-type. However, in contrast to the high virulence showed by the large spores of ΔcnaA, the spores from Δgpa11/Δgpa12 were avirulent and produced lower tissue invasion and cellular damage, suggesting that the gpa11 and gpa12 define a signal pathway with two branches. One of the branches controls spore size through regulation of calcineurin pathway, whereas virulences is controlled by an independent pathway. This virulence-related regulatory pathway could control the expression of genes involved in cellular responses important for virulence, since sporangiospores of Δgpa11/Δgpa12 were less resistant to oxidative stress and phagocytosis by macrophages than the ΔcnaA and wild-type strains. The characterization of this pathway could contribute to decipher the signals and mechanism used by Mucorales to produce mucormycosis.
Collapse
Affiliation(s)
- J. Alberto Patiño-Medina
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo (UMSNH), Morelia, Michoacán, México
| | - Nancy Y. Reyes-Mares
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo (UMSNH), Morelia, Michoacán, México
| | - Marco I. Valle-Maldonado
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo (UMSNH), Morelia, Michoacán, México
| | - Irvin E. Jácome-Galarza
- Departamento de Biología Molecular, Laboratorio Estatal de Salud Pública del Estado de Michoacán, Morelia, Michoacán, México
| | - Carlos Pérez-Arques
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, Murcia, España
| | - Rosa E. Nuñez-Anita
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Michoacana de San Nicolás Hidalgo, Morelia, Michoacán, Mexico
| | - Jesús Campos-García
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo (UMSNH), Morelia, Michoacán, México
| | - Verónica Anaya-Martínez
- Facultad de Ciencias de la Salud, Universidad Anáhuac, Naucalpan de Juarez, Estado de México, México
| | - Rafael Ortiz-Alvarado
- Facultad de Químico Farmacobiología, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Michoacan, México
| | - Martha I. Ramírez-Díaz
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo (UMSNH), Morelia, Michoacán, México
| | - Soo Chan Lee
- Department of Biology, South Texas Center of Emerging Infectious Diseases (STCEID), University of Texas at San Antonio, San Antonio, Texas, United States of America
| | - Victoriano Garre
- Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, Murcia, España
| | - Víctor Meza-Carmen
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo (UMSNH), Morelia, Michoacán, México
- * E-mail:
| |
Collapse
|
11
|
Xu Q, Hu LT, Wang Q, Lin J, Jiang N, Li C, Zhao GQ. Expression of macrophage migration inhibitory factor in Aspergillus fumigatus keratitis. Int J Ophthalmol 2019; 12:711-716. [PMID: 31131227 DOI: 10.18240/ijo.2019.05.03] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 02/18/2019] [Indexed: 12/21/2022] Open
Abstract
AIM To investigate the expression of macrophage migration inhibitory factor (MIF) and detect its role in the innate immune response of fungal keratitis (FK). METHODS We collected the paraffin-embedded cornea tissues from 10 FK and 6 ocular trauma patients to explore the MIF expression by immunohistochemistry. Then we cultured telomease-immortalized human corneal epithelial cells (THCEs), stimulated by the hyphae suspension of Aspergillus fumigatus (A. fumigatus) to detect the change of MIF with or without the pretreatment of MIF inhibitor [4-Iodo-6-phenylpyrimidine (4-IPP)] by real-time polymerase chain reaction (PCR). The protein level of MIF was also tested by immunohistochemistry, and the level of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) mRNA were compared between normal, hyphae stimulated and 4-IPP pretreated groups by real-time PCR to study the influence of MIF on the expression of TNF-α and IL-6. Corneal severity of rats' FK models was documented by clinical scores, and real-time PCR. Western blot and immunohistochemistry were used to test the expression of MIF, TNF-α and IL-6 in rats' corneas. RESULTS In the corneas of FK patients, there was much stronger expression of MIF than that in the normal group showed by immunohistochemistry. In cultured THCEs stimulated by A. fumigatus, the expression of MIF became stronger in both immunohistochemistry and PCR at 16, 24, 32 and 48h post infection (p.i.; P<0.01, P<0.01, P<0.01, P<0.05). After pretreated with 4-IPP, the expression of MIF reduced at 4, 8, 16h p.i. (P<0.05, P<0.05, P<0.05) and the downstream TNF-α and IL-6 decreased obviously (P<0.05, P<0.01). In rats with A. fumigatus keratitis, the relative mRNA and protein level of MIF increased than those in the normal group by PCR (at 1d: P<0.01, 3d: P<0.01, 5d: P<0.01), Western blot and immunohistochemistry. After blocked MIF with 4-IPP, the clinical outcomes of rat keratitis showed markedly reduced inflammatory response (P<0.01), with TNF-α and IL-6 decreased in accordance with those in THCEs by PCR (P<0.05, P<0.01). CONCLUSION The expression of MIF increased significantly in FK patients, THCEs and rats stimulated by A. fumigatus. After blocked with 4-IPP, the expression of MIF reduced, and so did its downstream cytokines: TNF-α and IL-6. The inflammation reaction of the rats' corneas lightened after pretreated with 4-IPP. MIF may play a role in the innate immune response of the corneal resistance against A. fumigatus.
Collapse
Affiliation(s)
- Qiang Xu
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| | - Li-Ting Hu
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| | - Qian Wang
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| | - Jing Lin
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| | - Nan Jiang
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| | - Cui Li
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| | - Gui-Qiu Zhao
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266000, Shandong Province, China
| |
Collapse
|
12
|
Peng X, Zhao G, Lin J, Qu J, Zhang Y, Li C. Phospholipase Cγ2 is critical for Ca 2+ flux and cytokine production in anti-fungal innate immunity of human corneal epithelial cells. BMC Ophthalmol 2018; 18:170. [PMID: 30005593 PMCID: PMC6043966 DOI: 10.1186/s12886-018-0847-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 07/06/2018] [Indexed: 11/10/2022] Open
Abstract
Background Fungal keratitis (FK) is a sight-threatening disease, accounting for a significant portion with its complex presentation, suboptimal efficacy of the existing therapies and uncontrollable excessive innate inflammation. Phospholipase C-γ2 (PLCγ2) is a non-receptor tyrosine kinase that plays an important role at the early period of innate immunity. This study aimed to identify the role of PLCγ2 in Dectin-1-mediated Ca2+ Flux and its effect on the expression of proinflammatory mediators at the exposure to Aspergillus fumigatus (A. fumigatus) hyphae antigens in human corneal epithelial cells (HCECs). Methods The HCECs were preincubated with or without different inhibitors respectively before A. fumigatus hyphae stimulation. Intracellular calcium flux in HCECs and levels of PLCγ2 and spleen-tyrosine kinase (Syk) were detected by fluorescence imaging and Western Blotting. The expression of proinflammatory mediators was determined by reverse transcriptase polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Results We demonstrated that an intracellular Ca2+ flux in HCECs was triggered by A. fumigatus hyphae and could be reduced by pre-treatment with PLCγ2-inhibitor U73122. A. fumigatus hyphae induced PLCγ2 phosphorylation was regulated by Dectin-1 via Syk. Furthermore, PLCγ2-deficient HCECs showed a drastic impairment in the Ca2+ signaling and the secretion of IL-6, CXCL1 and TNF-α. Conclusions PLCγ2 plays a critical role for Ca2+ Flux in HCECs stimulated by A. fumigatus hyphae. Syk acts upstream of PLCγ2 in the Dectin-1 signaling pathway. The expressions of proinflammatory mediators induced by A. fumigatus are regulated by the activation of Dectin-1-mediated PLCγ2 signaling pathway in HCECs.
Collapse
Affiliation(s)
- Xudong Peng
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, NO. 16 Jiangsu Road, Qingdao, 266003, Shandong Province, China
| | - Guiqiu Zhao
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, NO. 16 Jiangsu Road, Qingdao, 266003, Shandong Province, China.
| | - Jing Lin
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, NO. 16 Jiangsu Road, Qingdao, 266003, Shandong Province, China
| | - Jianqiu Qu
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, NO. 16 Jiangsu Road, Qingdao, 266003, Shandong Province, China
| | - Yingxue Zhang
- Department of Biochemistry, Immunology and Microbiology, Wayne State University School of Medicine, 540 E. Canfield Avenue, Detroit, MI, 48201, USA
| | - Cui Li
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, NO. 16 Jiangsu Road, Qingdao, 266003, Shandong Province, China
| |
Collapse
|
13
|
Xu R, Lin J, Zhao GQ, Li C, Che CY, Xu Q, Liu M. Production of interleukin-1β related to mammalian target of rapamycin/Toll-like receptor 4 signaling pathway during Aspergillus fumigatus infection of the mouse cornea. Int J Ophthalmol 2018; 11:712-718. [PMID: 29862167 DOI: 10.18240/ijo.2018.05.02] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 03/19/2018] [Indexed: 12/15/2022] Open
Abstract
AIM To elucidate the effect of rapamycin on regulating the production of interleukin (IL)-1β in Aspergillus fumigatus (A. fumigatus)-induced keratitis and to verify whether the expression of IL-1β in A. fumigatus keratitis is associated with the mammalian target of rapamycin (mTOR)/Toll-like receptor 4 (TLR4) signaling pathway. METHODS Fungal keratitis mouse models of susceptible C57BL/6 mice were established using A. fumigatus. The mice were subsequently treated with rapamycin. The protein levels of p-mTOR, TLR4, and IL-1β in normal and infected corneal tissue were measured by Western blot. The TLR4 and IL-1β mRNA levels were determined by real-time polymerase chain reaction (PCR). RESULTS In C57BL/6 mice, rapamycin treatment decreased the clinical scores and production of the pro-inflammatory cytokine, IL-1β. The expression of TLR4, stimulated by A. fumigatus, was reduced as well when the mTOR signaling pathway was suppressed by rapamycin. CONCLUSION Rapamycin is beneficial for the outcome of fungal keratitis and has an inhibitory effect expression of the inflammatory cytokine IL-1β. The inhibitory effect on IL-1β expression can be associated with the mTOR/TLR4 signaling pathway in A. fumigatus infection in mice.
Collapse
Affiliation(s)
- Rui Xu
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
| | - Jing Lin
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
| | - Gui-Qiu Zhao
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
| | - Cui Li
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
| | - Cheng-Ye Che
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
| | - Qiang Xu
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
| | - Min Liu
- Department of Ophthalmology, the Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong Province, China
| |
Collapse
|
14
|
In Vivo Biomarker Analysis of the Effects of Intranasally Dosed PC945, a Novel Antifungal Triazole, on Aspergillus fumigatus Infection in Immunocompromised Mice. Antimicrob Agents Chemother 2017. [PMID: 28630185 PMCID: PMC5571324 DOI: 10.1128/aac.00124-17] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
PC945 is a novel triazole optimized for lung delivery, and the objective of this study is to determine the effects of intranasally dosed PC945 on Aspergillus fumigatus infection and associated biomarkers in immunocompromised mice. PC945, posaconazole, or voriconazole was administered intranasally once daily on days 0 to 3 (early intervention) or days 1 to 3 (late intervention) postinfection in temporarily neutropenic A/J mice infected intranasally with A. fumigatus, and bronchoalveolar lavage fluid (BALF) and serum were collected on day 3. The effects of extended prophylaxis treatment (daily from days −7 to +3 or days −7 to 0) were also compared with those of the shorter treatment regimens (days −1 to +3 or days −1 and 0). Early and late interventions with PC945 (2.8 to 350 μg/mouse; approximately 0.11 to ∼14 mg/kg of body weight) were found to inhibit lung fungal loads and to decrease the concentrations of galactomannan (GM) in both BALF and serum as well as several biomarkers in BALF (interferon gamma [IFN-γ], interleukin-17 [IL-17], and malondialdehyde) and serum (tumor necrosis factor alpha [TNF-α] and IL-6) in a dose-dependent manner and were >3- and >47-fold more potent than intranasally dosed posaconazole and voriconazole, respectively. Furthermore, extended prophylaxis with low-dose PC945 (0.56 μg/mouse; 0.022 mg/kg) was found to inhibit fungal loads and to decrease the concentrations biomarkers more potently than did the shorter treatment regimens. Thus, PC945 dosed intranasally once daily showed potent antifungal effects, and the effects of PC945 accumulated upon repeat dosing and were persistent. Therefore, PC945 has the potential to be a novel inhaled therapy for the treatment of A. fumigatus infection in humans.
Collapse
|
15
|
Kolar SS, Baidouri H, McDermott AM. Role of Pattern Recognition Receptors in the Modulation of Antimicrobial Peptide Expression in the Corneal Epithelial Innate Response to F. solani. Invest Ophthalmol Vis Sci 2017; 58:2463-2472. [PMID: 28460048 PMCID: PMC5413214 DOI: 10.1167/iovs.16-20658] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Purpose Fusarium solani (F. solani) keratitis is a potentially sight-threatening fungal infection of the cornea. Antimicrobial peptides (AMPs), such as human β-defensins (hBDs) and cathelicidins, essential components of the immune system, likely have a protective role against F. solani keratitis. We examined the role of pattern recognition receptors (PRRs), Dectin-1, and TLR2 in F. solani–induced modulation of AMP expression in vitro. Methods Human corneal epithelial cells (HCECs) were exposed to heat-inactivated F. solani or pathogen-associated molecular patterns (PAMPs) of F. solani (Zymosan or Zymosan Depleted) for 6, 12, or 24 hours following which AMP mRNA and protein levels were determined. Involvement of TLR2 and Dectin-1 was confirmed by using siRNA knock-down (TLR2 and Dectin-1) or chemical inhibitor BAY 61-3606 (Dectin-1). The functional significance of AMP upregulation was tested using culture supernatant from F. solani or PAMP-treated HCECs against F. solani in the presence of hBD2 or LL37 neutralizing antibody. Results We confirm that HCECs express Dectin-1 and TLR2. HCECs demonstrated upregulation of AMPs hBD2 and cathelicidin LL37 following exposure to heat-inactivated F. solani or PAMPs. TLR2 and Dectin-1 knockdown and BAY 61-3606 treatment decreased AMP mRNA upregulation confirming PRR involvement. The culture supernatant from F. solani or PAMP-treated HCECs showed substantial killing of F. solani and hBD2 or LL37 neutralizing antibody significantly decreased this effect implicating involvement of these AMPs. Conclusions These findings demonstrate that Dectin-1 and TLR2 have an important role in regulating F. solani-induced AMP expression in corneal epithelial cells.
Collapse
Affiliation(s)
- Satya Sree Kolar
- The Ocular Surface Institute, University of Houston, College of Optometry, Houston, Texas, United States
| | - Hasna Baidouri
- The Ocular Surface Institute, University of Houston, College of Optometry, Houston, Texas, United States
| | - Alison M McDermott
- The Ocular Surface Institute, University of Houston, College of Optometry, Houston, Texas, United States
| |
Collapse
|
16
|
Croft CA, Culibrk L, Moore MM, Tebbutt SJ. Interactions of Aspergillus fumigatus Conidia with Airway Epithelial Cells: A Critical Review. Front Microbiol 2016; 7:472. [PMID: 27092126 PMCID: PMC4823921 DOI: 10.3389/fmicb.2016.00472] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 03/21/2016] [Indexed: 02/05/2023] Open
Abstract
Aspergillus fumigatus is an environmental filamentous fungus that also acts as an opportunistic pathogen able to cause a variety of symptoms, from an allergic response to a life-threatening disseminated fungal infection. The infectious agents are inhaled conidia whose first point of contact is most likely to be an airway epithelial cell (AEC). The interaction between epithelial cells and conidia is multifaceted and complex, and has implications for later steps in pathogenesis. Increasing evidence has demonstrated a key role for the airway epithelium in the response to respiratory pathogens, particularly at early stages of infection; therefore, elucidating the early stages of interaction of conidia with AECs is essential to understand the establishment of infection in cohorts of at-risk patients. Here, we present a comprehensive review of the early interactions between A. fumigatus and AECs, including bronchial and alveolar epithelial cells. We describe mechanisms of adhesion, internalization of conidia by AECs, the immune response of AECs, as well as the role of fungal virulence factors, and patterns of fungal gene expression characteristic of early infection. A clear understanding of the mechanisms involved in the early establishment of infection by A. fumigatus could point to novel targets for therapy and prophylaxis.
Collapse
Affiliation(s)
- Carys A Croft
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver BC, Canada
| | - Luka Culibrk
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver BC, Canada
| | - Margo M Moore
- Department of Biological Sciences, Simon Fraser University, Burnaby BC, Canada
| | - Scott J Tebbutt
- Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, VancouverBC, Canada; Prevention of Organ Failure Centre of Excellence, VancouverBC, Canada; Department of Medicine, Division of Respiratory Medicine, University of British Columbia, VancouverBC, Canada
| |
Collapse
|