1
|
Xu Y, Ma Q, Ren J, Chen L, Guo W, Feng K, Zeng Z, Huang T, Cai Y. Using Machine Learning Methods in Identifying Genes Associated with COVID-19 in Cardiomyocytes and Cardiac Vascular Endothelial Cells. Life (Basel) 2023; 13:life13041011. [PMID: 37109540 PMCID: PMC10146712 DOI: 10.3390/life13041011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/02/2023] [Accepted: 04/08/2023] [Indexed: 04/29/2023] Open
Abstract
Corona Virus Disease 2019 (COVID-19) not only causes respiratory system damage, but also imposes strain on the cardiovascular system. Vascular endothelial cells and cardiomyocytes play an important role in cardiac function. The aberrant expression of genes in vascular endothelial cells and cardiomyocytes can lead to cardiovascular diseases. In this study, we sought to explain the influence of respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on the gene expression levels of vascular endothelial cells and cardiomyocytes. We designed an advanced machine learning-based workflow to analyze the gene expression profile data of vascular endothelial cells and cardiomyocytes from patients with COVID-19 and healthy controls. An incremental feature selection method with a decision tree was used in building efficient classifiers and summarizing quantitative classification genes and rules. Some key genes, such as MALAT1, MT-CO1, and CD36, were extracted, which exert important effects on cardiac function, from the gene expression matrix of 104,182 cardiomyocytes, including 12,007 cells from patients with COVID-19 and 92,175 cells from healthy controls, and 22,438 vascular endothelial cells, including 10,812 cells from patients with COVID-19 and 11,626 cells from healthy controls. The findings reported in this study may provide insights into the effect of COVID-19 on cardiac cells and further explain the pathogenesis of COVID-19, and they may facilitate the identification of potential therapeutic targets.
Collapse
Affiliation(s)
- Yaochen Xu
- Department of Mathematics, School of Sciences, Shanghai University, Shanghai 200444, China
| | - Qinglan Ma
- School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Jingxin Ren
- School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Lei Chen
- College of Information Engineering, Shanghai Maritime University, Shanghai 201306, China
| | - Wei Guo
- Key Laboratory of Stem Cell Biology, Shanghai Jiao Tong University School of Medicine (SJTUSM) & Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS), Shanghai 200030, China
| | - Kaiyan Feng
- Department of Computer Science, Guangdong AIB Polytechnic College, Guangzhou 510507, China
| | - Zhenbing Zeng
- Department of Mathematics, School of Sciences, Shanghai University, Shanghai 200444, China
| | - Tao Huang
- Bio-Med Big Data Center, CAS Key Laboratory of Computational Biology, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
- CAS Key Laboratory of Tissue Microenvironment and Tumor, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yudong Cai
- Department of Mathematics, School of Sciences, Shanghai University, Shanghai 200444, China
| |
Collapse
|
2
|
Ning L, Shishi Z, Bo W, Huiqing L. Targeting immunometabolism against acute lung injury. Clin Immunol 2023; 249:109289. [PMID: 36918041 PMCID: PMC10008193 DOI: 10.1016/j.clim.2023.109289] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 03/06/2023] [Accepted: 03/08/2023] [Indexed: 03/14/2023]
Abstract
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are life-threatening conditions triggered by multiple intra- and extra-pulmonary injury factors, characterized by complicated molecular mechanisms and high mortality. Great strides have been made in the field of immunometabolism to clarify the interplay between intracellular metabolism and immune function in the past few years. Emerging evidence unveils the crucial roles of immunometabolism in inflammatory response and ALI. During ALI, both macrophages and lymphocytes undergo robust metabolic reprogramming and discrete epigenetic changes after activated. Apart from providing ATP and biosynthetic precursors, these metabolic cellular reactions and processes in lung also regulate inflammation and immunity.In fact, metabolic reprogramming involving glucose metabolism and fatty acidoxidation (FAO) acts as a double-edged sword in inflammatory response, which not only drives inflammasome activation but also elicits anti-inflammatory response. Additionally, the features and roles of metabolic reprogramming in different immune cells are not exactly the same. Here, we outline the evidence implicating how adverse factors shape immunometabolism in differentiation types of immune cells during ALI and summarize key proteins associated with energy expenditure and metabolic reprogramming. Finally, novel therapeutic targets in metabolic intermediates and enzymes together with current challenges in immunometabolism against ALI were discussed.
Collapse
Affiliation(s)
- Li Ning
- Department of Thoracic Surgery, Renmin Hospital, Wuhan University, Wuhan, Hubei Province, China
| | - Zou Shishi
- Department of Thoracic Surgery, Renmin Hospital, Wuhan University, Wuhan, Hubei Province, China
| | - Wang Bo
- Department of Thoracic Surgery, Renmin Hospital, Wuhan University, Wuhan, Hubei Province, China.
| | - Lin Huiqing
- Department of Thoracic Surgery, Renmin Hospital, Wuhan University, Wuhan, Hubei Province, China.
| |
Collapse
|
3
|
Menezes dos Reis L, Berçot MR, Castelucci BG, Martins AJE, Castro G, Moraes-Vieira PM. Immunometabolic Signature during Respiratory Viral Infection: A Potential Target for Host-Directed Therapies. Viruses 2023; 15:v15020525. [PMID: 36851739 PMCID: PMC9965666 DOI: 10.3390/v15020525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/05/2023] [Accepted: 02/06/2023] [Indexed: 02/16/2023] Open
Abstract
RNA viruses are known to induce a wide variety of respiratory tract illnesses, from simple colds to the latest coronavirus pandemic, causing effects on public health and the economy worldwide. Influenza virus (IV), parainfluenza virus (PIV), metapneumovirus (MPV), respiratory syncytial virus (RSV), rhinovirus (RhV), and coronavirus (CoV) are some of the most notable RNA viruses. Despite efforts, due to the high mutation rate, there are still no effective and scalable treatments that accompany the rapid emergence of new diseases associated with respiratory RNA viruses. Host-directed therapies have been applied to combat RNA virus infections by interfering with host cell factors that enhance the ability of immune cells to respond against those pathogens. The reprogramming of immune cell metabolism has recently emerged as a central mechanism in orchestrated immunity against respiratory viruses. Therefore, understanding the metabolic signature of immune cells during virus infection may be a promising tool for developing host-directed therapies. In this review, we revisit recent findings on the immunometabolic modulation in response to infection and discuss how these metabolic pathways may be used as targets for new therapies to combat illnesses caused by respiratory RNA viruses.
Collapse
Affiliation(s)
- Larissa Menezes dos Reis
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
| | - Marcelo Rodrigues Berçot
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-270, SP, Brazil
| | - Bianca Gazieri Castelucci
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
| | - Ana Julia Estumano Martins
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
- Graduate Program in Genetics and Molecular Biology, Institute of Biology, University of Campinas, Campinas 13083-970, SP, Brazil
| | - Gisele Castro
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
| | - Pedro M. Moraes-Vieira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, University of Campinas, Campinas 13083-862, SP, Brazil
- Experimental Medicine Research Cluster (EMRC), University of Campinas, Campinas 13083-872, SP, Brazil
- Obesity and Comorbidities Research Center (OCRC), University of Campinas, Campinas 13083-872, SP, Brazil
- Correspondence:
| |
Collapse
|
4
|
Tao H, Xu Y, Zhang S. The Role of Macrophages and Alveolar Epithelial Cells in the Development of ARDS. Inflammation 2023; 46:47-55. [PMID: 36048270 PMCID: PMC9435414 DOI: 10.1007/s10753-022-01726-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 07/25/2022] [Accepted: 08/01/2022] [Indexed: 11/26/2022]
Abstract
Acute lung injury (ALI) usually causes acute respiratory distress syndrome (ARDS), or even death in critical ill patients. Immune cell infiltration in inflamed lungs is an important hallmark of ARDS. Macrophages are a type of immune cell that participate in the entire pathogenic trajectory of ARDS and most prominently via their interactions with lung alveolar epithelial cells (AECs). In the early stage of ARDS, classically activated macrophages secrete pro-inflammatory cytokines to clearance of the pathogens which may damage alveolar AECs cell structure and result in cell death. Paradoxically, in late stage of ARDS, anti-inflammatory cytokines secreted by alternatively activated macrophages dampen the inflammation response and promote epithelial regeneration and alveolar structure remodeling. In this review, we discuss the important role of macrophages and AECs in the progression of ARDS.
Collapse
Affiliation(s)
- Huan Tao
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430033, China
| | - Younian Xu
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430033, China.
| | - Shihai Zhang
- Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430033, China.
| |
Collapse
|
5
|
Osuna-Espinoza KY, Rosas-Taraco AG. Metabolism of NK cells during viral infections. Front Immunol 2023; 14:1064101. [PMID: 36742317 PMCID: PMC9889541 DOI: 10.3389/fimmu.2023.1064101] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 01/04/2023] [Indexed: 01/19/2023] Open
Abstract
Cellular metabolism is essential for the correct function of immune system cells, including Natural Killer cells (NK). These cells depend on energy to carry out their effector functions, especially in the early stages of viral infection. NK cells participate in the innate immune response against viruses and tumors. Their main functions are cytotoxicity and cytokine production. Metabolic changes can impact intracellular signals, molecule production, secretion, and cell activation which is essential as the first line of immune defense. Metabolic variations in different immune cells in response to a tumor or pathogen infection have been described; however, little is known about NK cell metabolism in the context of viral infection. This review summarizes the activation-specific metabolic changes in NK cells, the immunometabolism of NK cells during early, late, and chronic antiviral responses, and the metabolic alterations in NK cells in SARS-CoV2 infection. The modulation points of these metabolic routes are also discussed to explore potential new immunotherapies against viral infections.
Collapse
Affiliation(s)
- Kenia Y Osuna-Espinoza
- Faculty of Medicine, Department of Immunology, Universidad Autonoma de Nuevo Leon, Monterrey, Nuevo Leon, Mexico
| | - Adrián G Rosas-Taraco
- Faculty of Medicine, Department of Immunology, Universidad Autonoma de Nuevo Leon, Monterrey, Nuevo Leon, Mexico
| |
Collapse
|
6
|
Labarrere CA, Kassab GS. Glutathione: A Samsonian life-sustaining small molecule that protects against oxidative stress, ageing and damaging inflammation. Front Nutr 2022; 9:1007816. [PMID: 36386929 PMCID: PMC9664149 DOI: 10.3389/fnut.2022.1007816] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 10/12/2022] [Indexed: 11/26/2022] Open
Abstract
Many local and systemic diseases especially diseases that are leading causes of death globally like chronic obstructive pulmonary disease, atherosclerosis with ischemic heart disease and stroke, cancer and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 19 (COVID-19), involve both, (1) oxidative stress with excessive production of reactive oxygen species (ROS) that lower glutathione (GSH) levels, and (2) inflammation. The GSH tripeptide (γ- L-glutamyl-L-cysteinyl-glycine), the most abundant water-soluble non-protein thiol in the cell (1-10 mM) is fundamental for life by (a) sustaining the adequate redox cell signaling needed to maintain physiologic levels of oxidative stress fundamental to control life processes, and (b) limiting excessive oxidative stress that causes cell and tissue damage. GSH activity is facilitated by activation of the Kelch-like ECH-associated protein 1 (Keap1)-Nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) redox regulator pathway, releasing Nrf2 that regulates expression of genes controlling antioxidant, inflammatory and immune system responses. GSH exists in the thiol-reduced (>98% of total GSH) and disulfide-oxidized (GSSG) forms, and the concentrations of GSH and GSSG and their molar ratio are indicators of the functionality of the cell. GSH depletion may play a central role in inflammatory diseases and COVID-19 pathophysiology, host immune response and disease severity and mortality. Therapies enhancing GSH could become a cornerstone to reduce severity and fatal outcomes of inflammatory diseases and COVID-19 and increasing GSH levels may prevent and subdue these diseases. The life value of GSH makes for a paramount research field in biology and medicine and may be key against systemic inflammation and SARS-CoV-2 infection and COVID-19 disease. In this review, we emphasize on (1) GSH depletion as a fundamental risk factor for diseases like chronic obstructive pulmonary disease and atherosclerosis (ischemic heart disease and stroke), (2) importance of oxidative stress and antioxidants in SARS-CoV-2 infection and COVID-19 disease, (3) significance of GSH to counteract persistent damaging inflammation, inflammaging and early (premature) inflammaging associated with cell and tissue damage caused by excessive oxidative stress and lack of adequate antioxidant defenses in younger individuals, and (4) new therapies that include antioxidant defenses restoration.
Collapse
|
7
|
Labarrere CA, Kassab GS. Glutathione deficiency in the pathogenesis of SARS-CoV-2 infection and its effects upon the host immune response in severe COVID-19 disease. Front Microbiol 2022; 13:979719. [PMID: 36274722 PMCID: PMC9582773 DOI: 10.3389/fmicb.2022.979719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 09/14/2022] [Indexed: 01/08/2023] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 19 (COVID-19) has numerous risk factors leading to severe disease with high mortality rate. Oxidative stress with excessive production of reactive oxygen species (ROS) that lower glutathione (GSH) levels seems to be a common pathway associated with the high COVID-19 mortality. GSH is a unique small but powerful molecule paramount for life. It sustains adequate redox cell signaling since a physiologic level of oxidative stress is fundamental for controlling life processes via redox signaling, but excessive oxidation causes cell and tissue damage. The water-soluble GSH tripeptide (γ-L-glutamyl-L-cysteinyl-glycine) is present in the cytoplasm of all cells. GSH is at 1–10 mM concentrations in all mammalian tissues (highest concentration in liver) as the most abundant non-protein thiol that protects against excessive oxidative stress. Oxidative stress also activates the Kelch-like ECH-associated protein 1 (Keap1)-Nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) redox regulator pathway, releasing Nrf2 to regulate the expression of genes that control antioxidant, inflammatory and immune system responses, facilitating GSH activity. GSH exists in the thiol-reduced and disulfide-oxidized (GSSG) forms. Reduced GSH is the prevailing form accounting for >98% of total GSH. The concentrations of GSH and GSSG and their molar ratio are indicators of the functionality of the cell and its alteration is related to various human pathological processes including COVID-19. Oxidative stress plays a prominent role in SARS-CoV-2 infection following recognition of the viral S-protein by angiotensin converting enzyme-2 receptor and pattern recognition receptors like toll-like receptors 2 and 4, and activation of transcription factors like nuclear factor kappa B, that subsequently activate nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) expression succeeded by ROS production. GSH depletion may have a fundamental role in COVID-19 pathophysiology, host immune response and disease severity and mortality. Therapies enhancing GSH could become a cornerstone to reduce severity and fatal outcomes of COVID-19 disease and increasing GSH levels may prevent and subdue the disease. The life value of GSH makes for a paramount research field in biology and medicine and may be key against SARS-CoV-2 infection and COVID-19 disease.
Collapse
|
8
|
Zhu JY, Wang G, Huang X, Lee H, Lee JG, Yang P, van de Leemput J, Huang W, Kane MA, Yang P, Han Z. SARS-CoV-2 Nsp6 damages Drosophila heart and mouse cardiomyocytes through MGA/MAX complex-mediated increased glycolysis. Commun Biol 2022; 5:1039. [PMID: 36180527 PMCID: PMC9523645 DOI: 10.1038/s42003-022-03986-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 09/13/2022] [Indexed: 12/01/2022] Open
Abstract
SARS-CoV-2 infection causes COVID-19, a severe acute respiratory disease associated with cardiovascular complications including long-term outcomes. The presence of virus in cardiac tissue of patients with COVID-19 suggests this is a direct, rather than secondary, effect of infection. Here, by expressing individual SARS-CoV-2 proteins in the Drosophila heart, we demonstrate interaction of virus Nsp6 with host proteins of the MGA/MAX complex (MGA, PCGF6 and TFDP1). Complementing transcriptomic data from the fly heart reveal that this interaction blocks the antagonistic MGA/MAX complex, which shifts the balance towards MYC/MAX and activates glycolysis-with similar findings in mouse cardiomyocytes. Further, the Nsp6-induced glycolysis disrupts cardiac mitochondrial function, known to increase reactive oxygen species (ROS) in heart failure; this could explain COVID-19-associated cardiac pathology. Inhibiting the glycolysis pathway by 2-deoxy-D-glucose (2DG) treatment attenuates the Nsp6-induced cardiac phenotype in flies and mice. These findings point to glycolysis as a potential pharmacological target for treating COVID-19-associated heart failure.
Collapse
Affiliation(s)
- Jun-Yi Zhu
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
| | - Guanglei Wang
- Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Xiaohu Huang
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
| | - Hangnoh Lee
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
| | - Jin-Gu Lee
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
| | - Penghua Yang
- Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Joyce van de Leemput
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA
| | - Weiliang Huang
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD, 21201, USA
- University of Queensland, Brisbane, QLD, 4072, Australia
| | - Maureen A Kane
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD, 21201, USA
| | - Peixin Yang
- Department of Obstetrics, Gynecology & Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Zhe Han
- Center for Precision Disease Modeling, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA.
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, 670 West Baltimore Street, Baltimore, MD, 21201, USA.
| |
Collapse
|
9
|
Huckestein BR, Alcorn JF. Improving Mitochondrial Function in Viral Infection: Targeting Cellular Metabolism. Am J Respir Cell Mol Biol 2022; 66:598-600. [PMID: 35442855 PMCID: PMC9163644 DOI: 10.1165/rcmb.2022-0096ed] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Brydie R Huckestein
- Children's Hospital of Pittsburgh of UPMC, 6619, Pittsburgh, Pennsylvania, United States
| | - John F Alcorn
- Children's Hospital of Pittsburgh of UPMC, Pediatrics, Pittsburgh, Pennsylvania, United States;
| |
Collapse
|