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Li J, Feng R, Zhang X, Hou W, Zhang Y, Li J, Li X, Jian F, Zhang L, Zhang S, Wang R. miR-181d targets BCL2 to regulate HCT-8 cell apoptosis and parasite burden in response to Cryptosporidium parvum infection via the intrinsic apoptosis pathway. Vet Parasitol 2024; 330:110237. [PMID: 38878462 DOI: 10.1016/j.vetpar.2024.110237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 06/11/2024] [Accepted: 06/11/2024] [Indexed: 07/20/2024]
Abstract
Cryptosporidium parvum is an important zoonotic pathogen that is studied worldwide. MicroRNAs (miRNAs) act as post-transcriptional regulators and may play a key role in modulating host epithelial responses following Cryptosporidium infection. Our previous study has shown that C. parvum downregulates the expression of miR-181d through the p50-dependent TLRs/NF-κB pathway. However, the mechanism by which miR-181d regulates host cells in response to C. parvum infection remains unclear. The present study found that miR-181d downregulation inhibited cell apoptosis and increased parasite burden in HCT-8 cells after C. parvum infection. Bioinformatics analysis and luciferase reporter assays have shown that BCL2 was a target gene for miR-181d. Moreover, BCL2 overexpression and miR-181d downregulation had similar results. To further investigate the mechanism by which miR-181d regulated HCT-8 cell apoptosis during C. parvum infection, the expression of molecules involved in the intrinsic apoptosis pathway was detected. Bax, caspase-9, and caspase-3 expression was decreased at 4, 8, 12, and 24 hpi and upregulated at 36 and 48 hpi. Interfering with the expression of miR-181d or BCL2 significantly affected the expression of molecules in the intrinsic apoptosis pathway. These data indicated that miR-181d targeted BCL2 to regulate HCT-8 cell apoptosis and parasite burden in response to C. parvum infection via the intrinsic apoptosis pathway. These results allowed us to further understand the regulatory mechanisms of host miRNAs during Cryptosporidium infection, and provided a theoretical foundation for the design and development of anti-cryptosporidiosis drugs.
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Affiliation(s)
- Juanfeng Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Ruiying Feng
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Xiaotian Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Wenyan Hou
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Yingying Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Junqiang Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Xiaoying Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Fuchun Jian
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Longxian Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China
| | - Sumei Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China.
| | - Rongjun Wang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China; Key Laboratory of Quality and Safety Control of Poultry Products, Ministry of Agriculture and Rural Affairs, Zhengzhou 450046, China; International Joint Research Laboratory for Zoonotic Diseases of Henan, Zhengzhou 450046, China.
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Yao Q, Fan YY, Huang S, Hu GR, Song JK, Yang X, Zhao GH. MiR-4521 affects the propagation of Cryptosporidium parvum in HCT-8 cells through targeting foxm1 by regulating cell apoptosis. Acta Trop 2024; 249:107057. [PMID: 37913972 DOI: 10.1016/j.actatropica.2023.107057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Revised: 10/24/2023] [Accepted: 10/29/2023] [Indexed: 11/03/2023]
Abstract
Cryptosporidium parvum could regulate the expression of microRNAs of epithelial cells to facilitate its intracellular propagation. MiR-4521 has been reported to play an important role during the development and progression of tumors and infectious diseases by regulating cell proliferation, apoptosis, and autophagy. However, the implication of miR-4521 during C. parvum infection was still unknown. In this study, the expression of miR-4521 was found to be upregulated in HCT-8 cells infected with C. parvum from 8 h post-infection (pi) to 48 hpi, and its upregulation would be related with the TLR/NF-κB signal pathway during C. parvum infection. One potential target of miR-4521, foxm1, was down-regulated in HCT-8 cells from 24 hpi to 48 hpi, and the expression of foxm1 was negatively regulated by miR-4521. The target relationship between miR-4521 and foxm1 was further validated by using dual luciferase reporter assay. Further studies showed that miR-4521 promoted the propagation of C. parvum in HCT-8 cells through targeting foxm1 by regulating BCL2-mediating cell apoptosis. These results contribute to further understanding of the regulatory mechanisms of host miRNAs during Cryptosporidium infection.
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Affiliation(s)
- Qian Yao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Ying-Ying Fan
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Shuang Huang
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Gui-Rong Hu
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Jun-Ke Song
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Xin Yang
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Guang-Hui Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China; Engineering Research Center of Efficient New Vaccines for Animals, Ministry of Education, Yangling 712100, China; Key Laboratory of Ruminant Disease Prevention and Control (West), Ministry of Agriculture and Rural Affairs, Yangling 712100, China; Engineering Research Center of Efficient New Vaccines for Animals, Universities of Shaanxi Province, Yangling 712100, China.
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Saraav I, Sibley LD. Dendritic Cells and Cryptosporidium: From Recognition to Restriction. Microorganisms 2023; 11:1056. [PMID: 37110479 PMCID: PMC10144555 DOI: 10.3390/microorganisms11041056] [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: 03/09/2023] [Revised: 03/29/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
Host immune responses are required for the efficient control of cryptosporidiosis. Immunity against Cryptosporidium infection has been best studied in mice, where it is mediated by both innate and adaptive immune responses. Dendritic cells are the key link between innate and adaptive immunity and participate in the defense against Cryptosporidium infection. While the effector mechanism varies, both humans and mice rely on dendritic cells for sensing parasites and restricting infection. Recently, the use of mouse-adapted strains C. parvum and mouse-specific strain C. tyzzeri have provided tractable systems to study the role of dendritic cells in mice against this parasite. In this review, we provide an overview of recent advances in innate immunity acting during infection with Cryptosporidium with a major focus on the role of dendritic cells in the intestinal mucosa. Further work is required to understand the role of dendritic cells in the activation of T cells and to explore associated molecular mechanisms. The identification of Cryptosporidium antigen involved in the activation of Toll-like receptor signaling in dendritic cells during infection is also a matter of future study. The in-depth knowledge of immune responses in cryptosporidiosis will help develop targeted prophylactic and therapeutic interventions.
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Affiliation(s)
| | - L. David Sibley
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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Mead JR. Early immune and host cell responses to Cryptosporidium infection. FRONTIERS IN PARASITOLOGY 2023; 2:1113950. [PMID: 37325809 PMCID: PMC10269812 DOI: 10.3389/fpara.2023.1113950] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Cryptosporidium spp. are opportunistic protozoan parasites that infect epithelial cells of the small intestine and cause diarrheal illness in both immunocompetent and immunodeficient individuals. These infections may be more severe in immunocompromised individuals and young children, especially in children under 2 in developing countries. The parasite has a global distribution and is an important cause of childhood diarrhea where it may result in cognitive impairment and growth deficits. Current therapies are limited with nitazoxanide being the only FDA-approved drug. However, it is not efficacious in immunocompromised patients. Additionally, there are no vaccines for cryptosporidiosis available. While acquired immunity is needed to clear Cryptosporidium parasites completely, innate immunity and early responses to infection are important in keeping the infection in check so that adaptive responses have time to develop. Infection is localized to the epithelial cells of the gut. Therefore, host cell defenses are important in the early response to infection and may be triggered through toll receptors or inflammasomes which induce a number of signal pathways, interferons, cytokines, and other immune mediators. Chemokines and chemokine receptors are upregulated which recruit immune cells such neutrophils, NK cells, and macrophages to the infection site to help in host cell defense as well as dendritic cells that are an important bridge between innate and adaptive responses. This review will focus on the host cell responses and the immune responses that are important in the early stages of infection.
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Affiliation(s)
- Jan R. Mead
- Department of Pediatrics, Children’s Healthcare Organization of Atlanta, Emory University, Atlanta, GA, United States
- Atlanta Veterans Affairs Medical Center, Decatur, GA, United States
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Xie F, Zhang Y, Li J, Sun L, Zhang L, Qi M, Zhang S, Jian F, Li X, Li J, Ning C, Wang R. MiR-942-5p targeting the IFI27 gene regulates HCT-8 cell apoptosis via a TRAIL-dependent pathway during the early phase of Cryptosporidium parvum infection. Parasit Vectors 2022; 15:291. [PMID: 35974384 PMCID: PMC9382849 DOI: 10.1186/s13071-022-05415-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 07/28/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND MicroRNAs (miRNAs) are involved in the regulation of both the innate and adaptive immune response to Cryptosporidium parvum infection. We previously reported that C. parvum upregulated miR‑942‑5p expression in HCT‑8 cells via TLR2/TLR4‑NF‑κB signaling. In the present study, the role of miRNA-942-5p in the regulation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated HCT-8 cell apoptosis induced by C. parvum was investigated. METHODS Quantitative real-time polymerase chain reaction, western blotting, flow cytometry, and immunofluorescence were used for analysis. RESULTS Forced expression of miRNA-942-5p resulted in decreased apoptosis and an increased C. parvum burden in HCT-8 cells. The opposite results were observed using the suppressed expression of miRNA-942-5p. The miRNA-942-5p led to the translational suppression of IFI27 gene through targeting the 3'-untranslated region of the IFI27 gene. Moreover, overexpression of the IFI27 gene produced a high apoptotic ratio and low C. parvum burden. In contrast, a low apoptotic ratio and a high C. parvum burden were observed following downregulation of the IFI27 gene. Both miR-942-5p and the IFI27 gene influenced TRAIL and caspase-8 expression induced by C. parvum in HCT-8 cells. Moreover, TRAIL promoted HCT-8 cell apoptosis in a concentration-dependent manner. CONCLUSIONS These data suggested that C. parvum induced the downregulation of IFI27 via relief of miR-942-5p-mediated translational suppression. IFI27 downregulation was affected the burden of C. parvum by regulating HCT-8 cell apoptosis through TRAIL-dependent pathways. Future studies should determine the mechanisms by which C. parvum infection increases miR-942-5p expression and the role of miR-942-5p in hosts' anti-C. parvum immunity in vivo.
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Affiliation(s)
- Fujie Xie
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Yajun Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Juanfeng Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Lulu Sun
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Longxian Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China.
| | - Meng Qi
- College of Animal Science, Tarim University, Alar, 843300, Xinjiang, China
| | - Sumei Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Fuchun Jian
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Xiaoying Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Junqiang Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Changsheng Ning
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China
| | - Rongjun Wang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, China.
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Certad G. Is Cryptosporidium a hijacker able to drive cancer cell proliferation? Food Waterborne Parasitol 2022; 27:e00153. [PMID: 35498550 PMCID: PMC9044164 DOI: 10.1016/j.fawpar.2022.e00153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/23/2022] [Accepted: 04/11/2022] [Indexed: 12/19/2022] Open
Abstract
The pathophysiological mechanisms of Cryptosporidium infection are multifactorial and not completely understood. Some advances achieved recently revealed that the infection by Cryptosporidium parvum induces cytoskeleton remodeling and actin reorganization through the implication of several intracellular signals involving, for example, PI3K, Src, Cdc42 and GTPases. It has also been reported that the infection by C. parvum leads to the activation of NF-κβ, known to induce anti-apoptotic mechanisms and to transmit oncogenic signals to epithelial cells. Despite the growing evidence about the hijacking of cellular pathways, potentially being involved in cancer onset, this information has rarely been linked to the tumorigenic potential of the parasite. However, several evidences support an association between Cryptosporidium infection and the development of digestive neoplasia. To explore the dynamics of Cryptosporidium infection, an animal model of cryptosporidiosis using corticoid dexamethasone-treated adult SCID (severe combined immunodeficiency) mice, orally infected with C. parvum or Cryptosporidium muris oocysts was implemented. C. parvum-infected animals developed digestive adenocarcinoma. When mechanisms involved in this neoplastic process were explored, the pivotal role of the Wnt pathway together with the alteration of the cytoskeleton was confirmed. Recently, a microarray assay allowed the detection of cancer-promoting genes and pathways highly up regulated in the group of C. parvum infected animals when compared to non-infected controls. Moreover, different human cases/control studies reported significant higher prevalence of Cryptosporidium infection among patients with recently diagnosed colon cancer before any treatment when compared to the control group (patients without colon neoplasia but with persistent digestive symptoms). These results suggest that Cryptosporidium is a potential oncogenic agent involved in cancer development beyond the usual suspects. If Cryptosporidium is able to hijack signal transduction, then is very likely that this contributes to transformation of its host cell. More research in the field is required in order to identify mechanisms and molecular factors involved in this process and to develop effective treatment interventions.
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Keddy KH, Saha S, Okeke IN, Kalule JB, Qamar FN, Kariuki S. Combating Childhood Infections in LMICs: evaluating the contribution of Big Data Big data, biomarkers and proteomics: informing childhood diarrhoeal disease management in Low- and Middle-Income Countries. EBioMedicine 2021; 73:103668. [PMID: 34742129 PMCID: PMC8579132 DOI: 10.1016/j.ebiom.2021.103668] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 09/26/2021] [Accepted: 10/20/2021] [Indexed: 01/20/2023] Open
Abstract
Despite efforts to reduce the global burden of childhood diarrhoea, 50% of all cases globally occur in children under five years in Low–Income and Middle- Income Countries (LMICs) and knowledge gaps remain regarding the aetiological diagnosis, introduction of diarrhoeal vaccines, and the role of environmental enteric dysfunction and severe acute malnutrition. Biomarkers may assist in understanding disease processes, from diagnostics, to management of childhood diarrhoea and the sequelae to vaccine development. Proteomics has the potential to assist in the identification of new biomarkers to understand the processes in the development of childhood diarrhoea and to aid in developing new vaccines. Centralised repositories that enable mining of large data sets to better characterise risk factors, the proteome of both the patient and the different diarrhoeal pathogens, and the environment, could inform patient management and vaccine development, providing a systems biological approach to address the burden of childhood diarrhoea in LMICs.
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Affiliation(s)
- Karen H Keddy
- Tuberculosis Platform, South African Medical Research Council, 1 Soutpansberg Rd, Pretoria, 0001, South Africa.
| | - Senjuti Saha
- Child Health Research Foundation, 23/2 Khilji Road, Mohammadpur, Dhaka 1207, Bangladesh
| | - Iruka N Okeke
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Ibadan, Oyo State, Nigeria
| | - John Bosco Kalule
- Biotechnical and Diagnostic Sciences, College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Uganda
| | - Farah Naz Qamar
- Department of Pediatrics and Child Health. Aga Khan University, Stadoum road Karachi, Pakistan 74800
| | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research Institute, Off Mbagathi Road, Nairobi, Kenya
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O'Leary JK, Sleator RD, Lucey B. Cryptosporidium spp. diagnosis and research in the 21 st century. Food Waterborne Parasitol 2021; 24:e00131. [PMID: 34471706 PMCID: PMC8390533 DOI: 10.1016/j.fawpar.2021.e00131] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/06/2021] [Accepted: 08/17/2021] [Indexed: 01/01/2023] Open
Abstract
The protozoan parasite Cryptosporidium has emerged as a leading cause of diarrhoeal illness worldwide, posing a significant threat to young children and immunocompromised patients. While endemic in the vast majority of developing countries, Cryptosporidium also has the potential to cause waterborne epidemics and large scale outbreaks in both developing and developed nations. Anthroponontic and zoonotic transmission routes are well defined, with the ingestion of faecally contaminated food and water supplies a common source of infection. Microscopy, the current diagnostic mainstay, is considered by many to be suboptimal. This has prompted a shift towards alternative diagnostic techniques in the advent of the molecular era. Molecular methods, particularly PCR, are gaining traction in a diagnostic capacity over microscopy in the diagnosis of cryptosporidiosis, given the laborious and often tedious nature of the latter. Until now, developments in the field of Cryptosporidium detection and research have been somewhat hampered by the intractable nature of this parasite. However, recent advances in the field have taken the tentative first steps towards bringing Cryptosporidium research into the 21st century. Herein, we provide a review of these advances.
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Affiliation(s)
- Jennifer K. O'Leary
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland
| | - Roy D. Sleator
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland
| | - Brigid Lucey
- Department of Biological Sciences, Munster Technological University, Bishopstown Campus, Cork, Ireland
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The role of osteoprotegerin (OPG) in fibrosis: its potential as a biomarker and/or biological target for the treatment of fibrotic diseases. Pharmacol Ther 2021; 228:107941. [PMID: 34171336 DOI: 10.1016/j.pharmthera.2021.107941] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 05/28/2021] [Indexed: 02/06/2023]
Abstract
Fibrosis is defined by excessive formation and accumulation of extracellular matrix proteins, produced by myofibroblasts, that supersedes normal wound healing responses to injury and results in progressive architectural remodelling. Fibrosis is often detected in advanced disease stages when an organ is already severely damaged and can no longer function properly. Therefore, there is an urgent need for reliable and easily detectable markers to identify and monitor fibrosis onset and progression as early as possible; this will greatly facilitate the development of novel therapeutic strategies. Osteoprotegerin (OPG), a well-known regulator of bone extracellular matrix and most studied for its role in regulating bone mass, is expressed in various organs and functions as a decoy for receptor activator of nuclear factor kappa-B ligand (RANKL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Recently, OPG has been linked to fibrosis and fibrogenesis, and has been included in a panel of markers to diagnose liver fibrosis. Multiple studies now suggest that OPG may be a general biomarker suitable for detection of fibrosis and/or monitoring the impact of fibrosis treatment. This review summarizes our current understanding of the role of OPG in fibrosis and will discuss its potential as a biomarker and/or novel therapeutic target for fibrosis.
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Crawford CK, Kol A. The Mucosal Innate Immune Response to Cryptosporidium parvum, a Global One Health Issue. Front Cell Infect Microbiol 2021; 11:689401. [PMID: 34113580 PMCID: PMC8185216 DOI: 10.3389/fcimb.2021.689401] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/07/2021] [Indexed: 02/02/2023] Open
Abstract
Cryptosporidium parvum is an apicomplexan parasite that infects the intestinal epithelium of humans and livestock animals worldwide. Cryptosporidiosis is a leading cause of diarrheal-related deaths in young children and a major cause of economic loss in cattle operations. The disease is especially dangerous to infants and immunocompromised individuals, for which there is no effective treatment or vaccination. As human-to-human, animal-to-animal and animal-to-human transmission play a role in cryptosporidiosis disease ecology, a holistic 'One Health' approach is required for disease control. Upon infection, the host's innate immune response restricts parasite growth and initiates the adaptive immune response, which is necessary for parasite clearance and recovery. The innate immune response involves a complex communicative interplay between epithelial and specialized innate immune cells. Traditional models have been used to study innate immune responses to C. parvum but cannot fully recapitulate natural host-pathogen interactions. Recent shifts to human and bovine organoid cultures are enabling deeper understanding of host-specific innate immunity response to infection. This review examines recent advances and highlights research gaps in our understanding of the host-specific innate immune response to C. parvum. Furthermore, we discuss evolving research models used in the field and potential developments on the horizon.
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Affiliation(s)
- Charles K Crawford
- Department of Pathology, Microbiology, & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Amir Kol
- Department of Pathology, Microbiology, & Immunology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
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Aguilar-Rojas A, Olivo-Marin JC, Guillen N. Human intestinal models to study interactions between intestine and microbes. Open Biol 2020; 10:200199. [PMID: 33081633 PMCID: PMC7653360 DOI: 10.1098/rsob.200199] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022] Open
Abstract
Implementations of suitable in vitro cell culture systems of the human intestine have been essential tools in the study of the interaction among organs, commensal microbiota, pathogens and parasites. Due to the great complexity exhibited by the intestinal tissue, researchers have been developing in vitro/ex vivo systems to diminish the gap between conventional cell culture models and the human intestine. These models are able to reproduce different structures and functional aspects of the tissue. In the present review, information is recapitulated on the most used models, such as cell culture, intestinal organoids, scaffold-based three-dimensional models, and organ-on-a-chip and their use in studying the interaction between human intestine and microbes, and their advantages and limitations are also discussed.
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Affiliation(s)
- Arturo Aguilar-Rojas
- Instituto Mexicano del Seguro Social, Unidad de Investigación Médica en Medicina Reproductiva, Unidad Médica de Alta Especialidad en Ginecología y Obstetricia No. 4 ‘Dr. Luis Castelazo Ayala’, Av. Río Magdalena No. 289, Col. Tizapán San Ángel, C.P. 01090 Ciudad de México, México
- Institut Pasteur, Unité d'Analyse d'Images Biologiques, 25 Rue du Dr Roux, 75015 Paris, France
| | - Jean-Christophe Olivo-Marin
- Institut Pasteur, Unité d'Analyse d'Images Biologiques, 25 Rue du Dr Roux, 75015 Paris, France
- Centre National de la Recherche Scientifique, UMR3691, 25 Rue du Dr Roux, 75015 Paris, France
| | - Nancy Guillen
- Institut Pasteur, Unité d'Analyse d'Images Biologiques, 25 Rue du Dr Roux, 75015 Paris, France
- Centre National de la Recherche Scientifique, ERL9195, 25 Rue du Dr Roux, 75015 Paris, France
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Kobayashi-Sakamoto M, Maeda T, Yusa J, Kato Y, Kiyoura Y. RANK-RANKL signaling upregulates Il-10 mRNA expression in mucosal Candida infection in vivo. Microb Pathog 2020; 149:104285. [PMID: 32585292 DOI: 10.1016/j.micpath.2020.104285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/17/2020] [Accepted: 05/26/2020] [Indexed: 10/24/2022]
Abstract
Osteoprotegerin (OPG) prevents binding of receptor activator of nuclear factor-kappa B ligand (RANKL) to RANK. Recent studies have reported that immune cell RANK-RANKL interactions are critical to the infection process. Candida albicans is an opportunistic pathogenic fungus and a common cause of candidiasis. This study utilized an orally inoculated mouse model of C. albicans infection to determine whether superficial or systemic candidiasis was associated with alterations in RANK/RANKL/OPG expression. Invasive systemic C. albicans infection increased serum OPG levels in mice. In addition, tongue Opg, Rankl, and Rank mRNA expression were upregulated in mice with superficial oral cavity C. albicans infection. Moreover, administration of exogenous soluble RANKL upregulated Rank and interleukin-10 (Il-10) mRNA in superficially infected tissue, suggesting suppression of localized inflammation. Taken together, these findings suggested that RANK/RANKL/OPG signaling contributes to the pathogenesis of candidiasis. This is the first in vivo study to identify a relationship between this opportunistic infection and the RANK/RANKL/OPG axis.
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Affiliation(s)
- Michiyo Kobayashi-Sakamoto
- Department of Preventive Dentistry, Ohu University School of Dentistry, Koriyama, Fukushima, 963-8611, Japan.
| | - Toyonobu Maeda
- Department of Oral Function and Molecular Biology, Ohu University School of Dentistry, Japan
| | - Junko Yusa
- Department of Oral of Pathology, Ohu University School of Dentistry, Japan
| | - Yasumasa Kato
- Department of Oral Function and Molecular Biology, Ohu University School of Dentistry, Japan
| | - Yusuke Kiyoura
- Department of Oral Medical Science, Ohu University School of Dentistry, Japan
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13
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Cryptosporidium parvum Subtilisin-Like Serine Protease (SUB1) Is Crucial for Parasite Egress from Host Cells. Infect Immun 2019; 87:IAI.00784-18. [PMID: 30782859 DOI: 10.1128/iai.00784-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/28/2019] [Indexed: 01/28/2023] Open
Abstract
Despite the severity and global burden of Cryptosporidium infection, treatments are less than optimal, and there is no effective vaccine. Egress from host cells is a key process for the completion of the life cycle of apicomplexan parasites. For Plasmodium species, subtilisin-like serine protease (SUB1) is a key mediator of egress. For Toxoplasma species, calcium-dependent protein kinases (CDPKs) are critical. In this study, we characterized Cryptosporidium SUB1 expression and evaluated its effect using an infection model. We found increased expression between 12 and 20 h after in vitro infection, prior to egress. We induced silencing of SUB1 (ΔSUB1) mRNA using SUB1 single-stranded antisense RNA coupled with human Argonaute 2. Silencing of SUB1 mRNA expression did not affect parasite viability, excystation, or invasion of target cells. However, knockdown led to a 95% decrease in the proportion of released merozoites in vitro (P < 0.0001). In contrast, silencing of CDPK5 had no effect on egress. Overall, our results indicate that SUB1 is a key mediator of Cryptosporidium egress and suggest that interruption of the life cycle at this stage may effectively inhibit the propagation of infection.
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14
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Bones AJ, Jossé L, More C, Miller CN, Michaelis M, Tsaousis AD. Past and future trends of Cryptosporidium in vitro research. Exp Parasitol 2018; 196:28-37. [PMID: 30521793 PMCID: PMC6333944 DOI: 10.1016/j.exppara.2018.12.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 11/09/2018] [Accepted: 12/02/2018] [Indexed: 12/15/2022]
Abstract
Cryptosporidium is a genus of single celled parasites capable of infecting a wide range of animals including humans. Cryptosporidium species are members of the phylum apicomplexa, which includes well-known genera such as Plasmodium and Toxoplasma. Cryptosporidium parasites cause a severe gastro-intestinal disease known as cryptosporidiosis. They are one of the most common causes of childhood diarrhoea worldwide, and infection can have prolonged detrimental effects on the development of children, but also can be life threatening to HIV/AIDS patients and transplant recipients. A variety of hosts can act as reservoirs, and Cryptosporidium can persist in the environment for prolonged times as oocysts. While there has been substantial interest in these parasites, there is very little progress in terms of treatment development and understanding the majority of the life cycle of this unusual organism. In this review, we will provide an overview on the existing knowledge of the biology of the parasite and the current progress in developing in vitro cultivation systems. We will then describe a synopsis of current and next generation approaches that could spearhead further research in combating the parasite.
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Affiliation(s)
- Alexander J Bones
- Laboratory of Molecular and Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury, Kent, UK
| | - Lyne Jossé
- Laboratory of Molecular and Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury, Kent, UK
| | - Charlotte More
- Laboratory of Molecular and Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury, Kent, UK
| | - Christopher N Miller
- Laboratory of Molecular and Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury, Kent, UK
| | | | - Anastasios D Tsaousis
- Laboratory of Molecular and Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury, Kent, UK; School of Biosciences, University of Kent, Canterbury, Kent, UK.
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15
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Barber BE, Grigg MJ, Piera KA, William T, Cooper DJ, Plewes K, Dondorp AM, Yeo TW, Anstey NM. Intravascular haemolysis in severe Plasmodium knowlesi malaria: association with endothelial activation, microvascular dysfunction, and acute kidney injury. Emerg Microbes Infect 2018; 7:106. [PMID: 29872039 PMCID: PMC5988665 DOI: 10.1038/s41426-018-0105-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 05/03/2018] [Accepted: 05/08/2018] [Indexed: 12/29/2022]
Abstract
Plasmodium knowlesi occurs throughout Southeast Asia, and is the most common cause of human malaria in Malaysia. Severe disease in humans is characterised by high parasite biomass, reduced red blood cell deformability, endothelial activation and microvascular dysfunction. However, the roles of intravascular haemolysis and nitric oxide (NO)-dependent endothelial dysfunction, important features of severe falciparum malaria, have not been evaluated, nor their role in acute kidney injury (AKI). In hospitalised Malaysian adults with severe (n = 48) and non-severe (n = 154) knowlesi malaria, and in healthy controls (n = 50), we measured cell-free haemoglobin (CFHb) and assessed associations with the endothelial Weibel–Palade body (WPB) constituents, angiopoietin-2 and osteoprotegerin, endothelial and microvascular function, and other markers of disease severity. CFHb was increased in knowlesi malaria in proportion to disease severity, and to a greater extent than previously reported in severe falciparum malaria patients from the same study cohort. In knowlesi malaria, CFHb was associated with parasitaemia, and independently associated with angiopoietin-2 and osteoprotegerin. As with angiopoietin-2, osteoprotegerin was increased in proportion to disease severity, and independently associated with severity markers including creatinine, lactate, interleukin-6, endothelial cell adhesion molecules ICAM-1 and E-selectin, and impaired microvascular reactivity. Osteoprotegerin was also independently associated with NO-dependent endothelial dysfunction. AKI was found in 88% of those with severe knowlesi malaria. Angiopoietin-2 and osteoprotegerin were both independent risk factors for acute kidney injury. Our findings suggest that haemolysis-mediated endothelial activation and release of WPB constituents is likely a key contributor to end-organ dysfunction, including AKI, in severe knowlesi malaria.
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Affiliation(s)
- Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia. .,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia.
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Kim A Piera
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia.,Jesselton Medical Centre, Kota Kinabalu, Sabah, Malaysia.,Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia
| | - Daniel J Cooper
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Katherine Plewes
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.,Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Arjen M Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.,Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Singapore, Singapore
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
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16
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Chao AT, Lee BH, Wan KF, Selva J, Zou B, Gedeck P, Beer DJ, Diagana TT, Bonamy GMC, Manjunatha UH. Development of a Cytopathic Effect-Based Phenotypic Screening Assay against Cryptosporidium. ACS Infect Dis 2018; 4:635-645. [PMID: 29341586 DOI: 10.1021/acsinfecdis.7b00247] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cryptosporidiosis is a diarrheal disease predominantly caused by Cryptosporidium parvum ( Cp) and Cryptosporidium hominis ( Ch), apicomplexan parasites which infect the intestinal epithelial cells of their human hosts. The only approved drug for cryptosporidiosis is nitazoxanide, which shows limited efficacy in immunocompromised children, the most vulnerable patient population. Thus, new therapeutics and in vitro infection models are urgently needed to address the current unmet medical need. Toward this aim, we have developed novel cytopathic effect (CPE)-based Cp and Ch assays in human colonic tumor (HCT-8) cells and compared them to traditional imaging formats. Further model validation was achieved through screening a collection of FDA-approved drugs and confirming many previously known anti- Cryptosporidium hits as well as identifying a few novel candidates. Collectively, our data reveals this model to be a simple, functional, and homogeneous gain of signal format amenable to high throughput screening, opening new avenues for the discovery of novel anticryptosporidials.
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Affiliation(s)
- Alexander T. Chao
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
- Novartis Institute for Tropical Diseases, 5300 Chiron Way, Emeryville, California 94608, United States
| | - Boon Heng Lee
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
| | - Kah Fei Wan
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
| | - Jeremy Selva
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
| | - Bin Zou
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
| | - Peter Gedeck
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
| | - David John Beer
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
| | - Thierry T. Diagana
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
- Novartis Institute for Tropical Diseases, 5300 Chiron Way, Emeryville, California 94608, United States
| | - Ghislain M. C. Bonamy
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos, Singapore, 138669, Singapore
| | - Ujjini H. Manjunatha
- Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore, 138670, Singapore
- Novartis Institute for Tropical Diseases, 5300 Chiron Way, Emeryville, California 94608, United States
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17
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Mirhashemi ME, Noubary F, Chapman-Bonofiglio S, Tzipori S, Huggins GS, Widmer G. Transcriptome analysis of pig intestinal cell monolayers infected with Cryptosporidium parvum asexual stages. Parasit Vectors 2018. [PMID: 29530089 PMCID: PMC5848449 DOI: 10.1186/s13071-018-2754-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Background Human cryptosporidiosis is caused primarily by two species of apicomplexan protozoa, Cryptosporidium parvum and C. hominis. In cultured cell monolayers, the parasite undergoes two generations of asexual multiplication (merogony). However, the proportion of parasites completing the life-cycle is low and insufficient to sustain continuous propagation. Due to the intracellular location of meronts and later life-cycle stages, oocyst and sporozoites are the only forms of the parasite that can readily be isolated. Results Research on the replicating forms of Cryptosporidium parasites and their interaction with the host cell remains challenging. Based on an RNA-Seq analysis of monolayers of pig epithelial cells infected with C. parvum, here we report on the impact of merogony on the host’s gene regulation. Analysis of the transcriptome of infected and uninfected monolayers demonstrates a significant impact of the infection on host cell gene expression. A total of 813 genes were differentially expressed. Functional terms significantly altered in response to infection include phosphoprotein, RNA binding and acetylation. Upregulation of cell cycle pathways indicates an increase in mitosis. Notably absent from differentially enriched functional categories are stress- and apoptosis-related functions. The comparison of the combined host-parasite transcriptome reveals that C. parvum gene expression is less diverse than the host cell transcriptome and is highly enriched for genes encoding ribosomal functions, such as ribosomal proteins. Conclusions These results indicate that C. parvum infection significantly changes host biological functions and provide new insight into gene functions driving early C. parvum intracellular development. Electronic supplementary material The online version of this article (10.1186/s13071-018-2754-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Marzieh Ezzaty Mirhashemi
- Clinical and Translational Institute, Sackler School of Biomedical Sciences, Tufts University, 136 Harrison Avenue, Boston, Massachusetts, 02111, USA.,Cummings School of Veterinary Medicine at Tufts University, Building 20, 200 Westborough Avenue, North Grafton, Massachusetts, 01536, USA
| | - Farzad Noubary
- Clinical and Translational Institute, Sackler School of Biomedical Sciences, Tufts University, 136 Harrison Avenue, Boston, Massachusetts, 02111, USA
| | - Susan Chapman-Bonofiglio
- Cummings School of Veterinary Medicine at Tufts University, Building 20, 200 Westborough Avenue, North Grafton, Massachusetts, 01536, USA
| | - Saul Tzipori
- Cummings School of Veterinary Medicine at Tufts University, Building 20, 200 Westborough Avenue, North Grafton, Massachusetts, 01536, USA
| | - Gordon S Huggins
- Clinical and Translational Institute, Sackler School of Biomedical Sciences, Tufts University, 136 Harrison Avenue, Boston, Massachusetts, 02111, USA
| | - Giovanni Widmer
- Cummings School of Veterinary Medicine at Tufts University, Building 20, 200 Westborough Avenue, North Grafton, Massachusetts, 01536, USA.
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18
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Baydoun M, Vanneste SB, Creusy C, Guyot K, Gantois N, Chabe M, Delaire B, Mouray A, Baydoun A, Forzy G, Chieux V, Gosset P, Senez V, Viscogliosi E, Follet J, Certad G. Three-dimensional (3D) culture of adult murine colon as an in vitro model of cryptosporidiosis: Proof of concept. Sci Rep 2017; 7:17288. [PMID: 29230047 PMCID: PMC5725449 DOI: 10.1038/s41598-017-17304-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 11/19/2017] [Indexed: 01/12/2023] Open
Abstract
Cryptosporidium parvum is a major cause of diarrheal illness and was recently potentially associated with digestive carcinogenesis. Despite its impact on human health, Cryptosporidium pathogenesis remains poorly known, mainly due to the lack of a long-term culture method for this parasite. Thus, the aim of the present study was to develop a three-dimensional (3D) culture model from adult murine colon allowing biological investigations of the host-parasite interactions in an in vivo-like environment and, in particular, the development of parasite-induced neoplasia. Colonic explants were cultured and preserved ex vivo for 35 days and co-culturing was performed with C. parvum. Strikingly, the resulting system allowed the reproduction of neoplastic lesions in vitro at 27 days post-infection (PI), providing new evidence of the role of the parasite in the induction of carcinogenesis. This promising model could facilitate the study of host-pathogen interactions and the investigation of the process involved in Cryptosporidium-induced cell transformation.
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Affiliation(s)
- Martha Baydoun
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France.,ISA-YNCREA Hauts-de-France, Lille, France.,Univ. Lille, CNRS, ISEN, UMR 8520 - IEMN, Lille, France
| | - Sadia Benamrouz Vanneste
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France.,Laboratoire Ecologie et Biodiversité, Faculté de Gestion Economie et Sciences, Institut Catholique de Lille, Lille, France
| | - Colette Creusy
- Service d'Anatomie et de Cytologie Pathologiques, Groupement des Hopitaux de l'Institut Catholique de Lille (GHICL), Lille, France
| | - Karine Guyot
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France
| | - Nausicaa Gantois
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France
| | - Magali Chabe
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France.,Faculté de Pharmacie, Univ. de Lille, Lille, France
| | - Baptiste Delaire
- Service d'Anatomie et de Cytologie Pathologiques, Groupement des Hopitaux de l'Institut Catholique de Lille (GHICL), Lille, France
| | - Anthony Mouray
- Plateforme d'Expérimentations et de Hautes Technologies Animales, Institut Pasteur de Lille, Lille, France
| | - Atallah Baydoun
- Department of Internal Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA.,Department of Internal Medicine, Louis Stokes VA Medical Center, Cleveland, OH, USA.,Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Gerard Forzy
- Laboratoire de Biologie Médicale, Groupement des Hospitaux de l'Institut Catholique de Lille (GHICL), Lille, France
| | - Vincent Chieux
- Laboratoire de Biologie Médicale, Groupement des Hospitaux de l'Institut Catholique de Lille (GHICL), Lille, France
| | - Pierre Gosset
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France.,Service d'Anatomie et de Cytologie Pathologiques, Groupement des Hopitaux de l'Institut Catholique de Lille (GHICL), Lille, France
| | - Vincent Senez
- Univ. Lille, CNRS, ISEN, UMR 8520 - IEMN, Lille, France
| | - Eric Viscogliosi
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France
| | - Jérôme Follet
- ISA-YNCREA Hauts-de-France, Lille, France.,Univ. Lille, CNRS, ISEN, UMR 8520 - IEMN, Lille, France
| | - Gabriela Certad
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, Lille, France. .,Département de la Recherche Médicale, Groupement des Hopitaux de l'Institut Catholique de Lille (GHICL), Faculté de Médecine et Maïeutique, Université Catholique de Lille, Lille, France.
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19
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Chakraborty S, Roy S, Mistry HU, Murthy S, George N, Bhandari V, Sharma P. Potential Sabotage of Host Cell Physiology by Apicomplexan Parasites for Their Survival Benefits. Front Immunol 2017; 8:1261. [PMID: 29081773 PMCID: PMC5645534 DOI: 10.3389/fimmu.2017.01261] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 09/21/2017] [Indexed: 12/26/2022] Open
Abstract
Plasmodium, Toxoplasma, Cryptosporidium, Babesia, and Theileria are the major apicomplexan parasites affecting humans or animals worldwide. These pathogens represent an excellent example of host manipulators who can overturn host signaling pathways for their survival. They infect different types of host cells and take charge of the host machinery to gain nutrients and prevent itself from host attack. The mechanisms by which these pathogens modulate the host signaling pathways are well studied for Plasmodium, Toxoplasma, Cryptosporidium, and Theileria, except for limited studies on Babesia. Theileria is a unique pathogen taking into account the way it modulates host cell transformation, resulting in its clonal expansion. These parasites majorly modulate similar host signaling pathways, however, the disease outcome and effect is different among them. In this review, we discuss the approaches of these apicomplexan to manipulate the host–parasite clearance pathways during infection, invasion, survival, and egress.
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Affiliation(s)
| | - Sonti Roy
- National Institute of Animal Biotechnology (NIAB-DBT), Hyderabad, India
| | - Hiral Uday Mistry
- National Institute of Animal Biotechnology (NIAB-DBT), Hyderabad, India
| | - Shweta Murthy
- National Institute of Animal Biotechnology (NIAB-DBT), Hyderabad, India
| | - Neena George
- National Institute of Animal Biotechnology (NIAB-DBT), Hyderabad, India
| | | | - Paresh Sharma
- National Institute of Animal Biotechnology (NIAB-DBT), Hyderabad, India
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20
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Laurent F, Lacroix-Lamandé S. Innate immune responses play a key role in controlling infection of the intestinal epithelium by Cryptosporidium. Int J Parasitol 2017; 47:711-721. [PMID: 28893638 DOI: 10.1016/j.ijpara.2017.08.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 07/24/2017] [Accepted: 08/23/2017] [Indexed: 12/15/2022]
Abstract
Cryptosporidium infection leads to acute diarrhea worldwide. The development of cryptosporidiosis is closely related to the immune status of its host, affecting primarily young ruminants, infants, and immunocompromised individuals. In recent years, several studies have improved our knowledge on the immune mechanisms responsible for the control of the acute phase of the infection and have highlighted the importance of innate immunity. The parasite develops in the apical side of intestinal epithelial cells, giving these cells a central role, as they are both the exclusive host cell for replication of the parasite and participate in the protective immune response. Epithelial cells signal the infection by producing chemokines, attracting immune cells to the infected area. They also actively participate in host defense by inducing apoptosis and releasing antimicrobial peptides, free or incorporated into luminal exosomes, with parasiticidal activity. The parasite has developed several escape mechanisms to slow down these protective mechanisms. Recent development of several three-dimensional culture models and the ability to genetically manipulate Cryptosporidium will greatly help to further investigate host-pathogen interactions and identify virulence factors. Intestinal epithelial cells require the help of immune cells to clear the infection. Intestinal dendritic cells, well known for their ability to induce and orchestrate adaptive immunity, play a key role in controlling the very early steps of Cryptosporidium parvum infection by acting as immunological sentinels and active effectors. However, inflammatory monocytes, which are quickly and massively recruited to the infected mucosa, seem to participate in the loss of epithelial integrity. In addition to new promising chemotherapies, we must consider stimulating the innate immunity of neonates to strengthen their ability to control Cryptosporidium development. The microbiota plays a fundamental role in the development of intestinal immunity and may be considered to be a third actor in host-pathogen interactions. There is an urgent need to reduce the incidence of this yet poorly controlled disease in the populations of developing countries, and decrease economic losses due to infected livestock.
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Affiliation(s)
- Fabrice Laurent
- UMR1282 Infectiologie et Santé Publique, INRA Centre Val de Loire, Université François Rabelais de Tours, 37380 Nouzilly, France.
| | - Sonia Lacroix-Lamandé
- UMR1282 Infectiologie et Santé Publique, INRA Centre Val de Loire, Université François Rabelais de Tours, 37380 Nouzilly, France.
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21
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Paredes JL, Sparks H, White AC, Martinez-Traverso G, Ochoa T, Castellanos-González A. Killing of Cryptosporidium sporozoites by Lactoferrin. Am J Trop Med Hyg 2017; 97:774-776. [PMID: 28722573 DOI: 10.4269/ajtmh.16-0804] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Intestinal infection caused by Cryptosporidium is a major contributor to diarrhea morbidity and mortality in young children around the world. Current treatments for children suffering from cryptosporidiosis are suboptimal. Lactoferrin is a glycoprotein found in breast milk. It has showed bacteriostatic and antimicrobial activity in the intestine. However, the effects of lactoferrin on the intestinal parasite Cryptosporidium have not been reported. In this study, we investigated the anticryptosporidial activity of human lactoferrin on different stages of Cryptosporidium. Physiologic concentrations of lactoferrin killed Cryptosporidium parvum sporozoites, but had no significant effect on oocysts viability or parasite intracellular development. Since sporozoites are essential for the infection process, our data reinforce the importance of breastfeeding and point to the potential of lactoferrin as a novel therapeutic agent for cryptosporidiosis.
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Affiliation(s)
| | - Hayley Sparks
- Infectious Diseases Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas
| | - A Clinton White
- Infectious Diseases Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas
| | - Griselle Martinez-Traverso
- Infectious Diseases Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston, Texas
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22
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Manjunatha UH, Vinayak S, Zambriski JA, Chao AT, Sy T, Noble CG, Bonamy GMC, Kondreddi RR, Zou B, Gedeck P, Brooks CF, Herbert GT, Sateriale A, Tandel J, Noh S, Lakshminarayana SB, Lim SH, Goodman LB, Bodenreider C, Feng G, Zhang L, Blasco F, Wagner J, Leong FJ, Striepen B, Diagana TT. A Cryptosporidium PI(4)K inhibitor is a drug candidate for cryptosporidiosis. Nature 2017; 546:376-380. [PMID: 28562588 PMCID: PMC5473467 DOI: 10.1038/nature22337] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 03/31/2017] [Indexed: 01/02/2023]
Abstract
Diarrhoeal disease is responsible for 8.6% of global child mortality. Recent epidemiological studies found the protozoan parasite Cryptosporidium to be a leading cause of paediatric diarrhoea, with particularly grave impact on infants and immunocompromised individuals. There is neither a vaccine nor an effective treatment. Here we establish a drug discovery process built on scalable phenotypic assays and mouse models that take advantage of transgenic parasites. Screening a library of compounds with anti-parasitic activity, we identify pyrazolopyridines as inhibitors of Cryptosporidium parvum and Cryptosporidium hominis. Oral treatment with the pyrazolopyridine KDU731 results in a potent reduction in intestinal infection of immunocompromised mice. Treatment also leads to rapid resolution of diarrhoea and dehydration in neonatal calves, a clinical model of cryptosporidiosis that closely resembles human infection. Our results suggest that the Cryptosporidium lipid kinase PI(4)K (phosphatidylinositol-4-OH kinase) is a target for pyrazolopyridines and that KDU731 warrants further preclinical evaluation as a drug candidate for the treatment of cryptosporidiosis. The establishment of a drug-discovery screening pipeline for cryptosporidiosis, and identification of pyrazolopyridines as selective ATP-competitive inhibitors of the Cryptosporidium lipid kinase PI(4)K. The apicomplexan parasite Cryptosporidium is a leading cause of paediatric diarrhoea, with high mortality in infants and individuals with weak immune systems. Here, the authors report the establishment of a drug discovery screening pipeline for cryptosporidiosis, and identify pyrazolopyridines as selective ATP-competitive inhibitors of the Cryptosporidium lipid kinase PI(4)K. The lead candidate, KDU731, inhibits growth of C. parvum and C. hominis in vitro, and demonstrated in vivo efficacy in immunocompromised mice and neonatal calves (a clinical model of human disease). Moreover, KDU731 meets a broad range of safety and pharmacology criteria, and has potential as a much-needed therapeutic for treatment of cryptosporidiosis.
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Affiliation(s)
| | - Sumiti Vinayak
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Jennifer A Zambriski
- Washington State University, College of Veterinary Medicine, Paul G. Allen School for Global Animal Health, Pullman, WA, USA
| | | | - Tracy Sy
- Washington State University, College of Veterinary Medicine, Paul G. Allen School for Global Animal Health, Pullman, WA, USA
| | | | | | | | - Bin Zou
- Novartis Institute for Tropical Diseases, Singapore 138670
| | - Peter Gedeck
- Novartis Institute for Tropical Diseases, Singapore 138670
| | - Carrie F Brooks
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Gillian T Herbert
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Adam Sateriale
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - Jayesh Tandel
- Department of Cellular Biology, University of Georgia, Athens, GA, USA
| | - Susan Noh
- Washington State University, College of Veterinary Medicine, Paul G. Allen School for Global Animal Health, Pullman, WA, USA.,USDA-Agricultural Research Service, Animal Disease Research Unit and Washington State University, Department of Veterinary Microbiology and Pathology, Washington Animal Disease Diagnostic Laboratory, Pullman, WA, USA
| | | | - Siau H Lim
- Novartis Institute for Tropical Diseases, Singapore 138670
| | - Laura B Goodman
- Cornell University, College of Veterinary Medicine, Department of Population Medicine and Diagnostic Sciences, Ithaca, NY, USA
| | | | - Gu Feng
- Novartis Institute for Tropical Diseases, Singapore 138670
| | - Lijun Zhang
- China Novartis Institute for Biomedical Research, Shanghai 201203, China
| | | | - Juergen Wagner
- Novartis Institute for Tropical Diseases, Singapore 138670
| | - F Joel Leong
- Novartis Institute for Tropical Diseases, Singapore 138670
| | - Boris Striepen
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA.,Department of Cellular Biology, University of Georgia, Athens, GA, USA
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Castellanos-Gonzalez A, Perry N, Nava S, White AC. Preassembled Single-Stranded RNA-Argonaute Complexes: A Novel Method to Silence Genes in Cryptosporidium. J Infect Dis 2016; 213:1307-14. [PMID: 26656125 PMCID: PMC4799669 DOI: 10.1093/infdis/jiv588] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/27/2015] [Indexed: 11/14/2022] Open
Abstract
Cryptosporidiosis is a common cause of diarrhea morbidity and mortality worldwide. Research progress on this infection has been slowed by lack of methods to genetically manipulate Cryptosporidium parasites. Small interfering RNA (siRNA) is widely used to study gene function, but Cryptosporidium species lack the enzymes necessary to process siRNA. By preassembling complexes with the human enzyme Argonaute 2 (hAgo2) and Cryptosporidium single-stranded RNA (ssRNA), we induced specific slicing in Cryptosporidium RNA targets. We demonstrated the reduction in expression of target genes at the mRNA and protein levels by transfecting live parasites with ssRNA-hAgo2 complexes. Furthermore we used this method to confirm the role of selected molecules during host cell invasion. This novel method provides a novel means of silencing Cryptosporidium genes to study their role in host-parasite interactions and as potential targets for chemotherapy.
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Affiliation(s)
| | - Nicolas Perry
- Infectious Disease Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston
| | - Samantha Nava
- Infectious Disease Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston
| | - A Clinton White
- Infectious Disease Division, Department of Internal Medicine, University of Texas Medical Branch, Galveston
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Di Genova BM, Tonelli RR. Infection Strategies of Intestinal Parasite Pathogens and Host Cell Responses. Front Microbiol 2016; 7:256. [PMID: 26973630 PMCID: PMC4776161 DOI: 10.3389/fmicb.2016.00256] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 02/16/2016] [Indexed: 12/24/2022] Open
Abstract
Giardia lamblia, Cryptosporidium sp., and Entamoeba histolytica are important pathogenic intestinal parasites and are amongst the leading causes worldwide of diarrheal illness in humans. Diseases caused by these organisms, giardiasis, cryptosporidiosis, and amoebiasis, respectively, are characterized by self-limited diarrhea but can evolve to long-term complications. The cellular and molecular mechanisms underlying the pathogenesis of diarrhea associated with these three pathogens are being unraveled, with knowledge of both the strategies explored by the parasites to establish infection and the methods evolved by hosts to avoid it. Special attention is being given to molecules participating in parasite–host interaction and in the mechanisms implicated in the diseases’ pathophysiologic processes. This review focuses on cell mechanisms that are modulated during infection, including gene transcription, cytoskeleton rearrangements, signal transduction pathways, and cell death.
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Affiliation(s)
- Bruno M Di Genova
- Departamento de Microbiologia e Imunologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Renata R Tonelli
- Departamento de Microbiologia e Imunologia, Universidade Federal de São PauloSão Paulo, Brazil; Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Departamento de Ciências Biológicas, Universidade Federal de São PauloDiadema, Brazil
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25
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Kuroda Y, Maruyama K, Fujii H, Sugawara I, Ko SBH, Yasuda H, Matsui H, Matsuo K. Osteoprotegerin Regulates Pancreatic β-Cell Homeostasis upon Microbial Invasion. PLoS One 2016; 11:e0146544. [PMID: 26751951 PMCID: PMC4709133 DOI: 10.1371/journal.pone.0146544] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 12/19/2015] [Indexed: 12/19/2022] Open
Abstract
Osteoprotegerin (OPG), a decoy receptor for receptor activator of NF-κB ligand (RANKL), antagonizes RANKL’s osteoclastogenic function in bone. We previously demonstrated that systemic administration of lipopolysaccharide (LPS) to mice elevates OPG levels and reduces RANKL levels in peripheral blood. Here, we show that mice infected with Salmonella, Staphylococcus, Mycobacteria or influenza virus also show elevated serum OPG levels. We then asked whether OPG upregulation following microbial invasion had an effect outside of bone. To do so, we treated mice with LPS and observed OPG production in pancreas, especially in β-cells of pancreatic islets. Insulin release following LPS administration was enhanced in mice lacking OPG, suggesting that OPG inhibits insulin secretion under acute inflammatory conditions. Consistently, treatment of MIN6 pancreatic β-cells with OPG decreased their insulin secretion following glucose stimulation in the presence of LPS. Finally, our findings suggest that LPS-induced OPG upregulation is mediated in part by activator protein (AP)-1 family transcription factors, particularly Fos proteins. Overall, we report that acute microbial infection elevates serum OPG, which maintains β-cell homeostasis by restricting glucose-stimulated insulin secretion, possibly preventing microbe-induced exhaustion of β-cell secretory capacity.
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Affiliation(s)
- Yukiko Kuroda
- Laboratory of Cell and Tissue Biology, Keio University School of Medicine, Tokyo, Japan
| | - Kenta Maruyama
- Laboratory of Host Defense, WPI Immunology Frontier Research Center (IFReC), Osaka University, Osaka, Japan
| | - Hideki Fujii
- Department of Immunology Graduate School of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Isamu Sugawara
- Mycobacterial Reference Center, The Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo, Japan
| | - Shigeru B. H. Ko
- Department of Systems Medicine, The Sakaguchi Laboratory, Keio University School of Medicine, Tokyo, Japan
| | - Hisataka Yasuda
- Nagahama Institute for Biochemical Science, Oriental Yeast Co., Shiga, Japan
| | - Hidenori Matsui
- Kitasato Institute for Life Sciences and Graduate School of Infection Control Sciences, Kitasato University, Tokyo, Japan
| | - Koichi Matsuo
- Laboratory of Cell and Tissue Biology, Keio University School of Medicine, Tokyo, Japan
- * E-mail:
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26
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Biomarkers of Gastrointestinal Host Responses to Microbial Infections. Mol Microbiol 2016. [DOI: 10.1128/9781555819071.ch46] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Ronza P, Bermúdez R, Losada AP, Sitjà-Bobadilla A, Pardo BG, Quiroga MI. Immunohistochemical detection and gene expression of TNFα in turbot (Scophthalmus maximus) enteromyxosis. FISH & SHELLFISH IMMUNOLOGY 2015; 47:368-376. [PMID: 26386194 DOI: 10.1016/j.fsi.2015.09.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 08/29/2015] [Accepted: 09/15/2015] [Indexed: 06/05/2023]
Abstract
Enteromyxum scophthalmi (Myxozoa) constitutes one of the most devastating pathogens for turbot (Scophthalmus maximus, L.) aquaculture. This parasite causes a severe intestinal parasitosis that leads to a cachectic syndrome with high morbidity and mortality rates for which no therapeutic options are available. Presence of inflammatory infiltrates, increased apoptotic rates and epithelial detaching have been described at intestinal level, as well as leukocyte depletion in lymphohaematopoietic organs. Previous investigations on enteromyxosis in turbot showed the high susceptibility of this species to the parasite and reported the existence of a dysregulated immune response against the parasite. The pleiotropic cytokine tumour necrosis factor alpha (TNFα) plays a major role in immune response and is involved in a wide range of biological activities. In teleost, the gene expression of this cytokine has been found regulated under several pathological conditions. Teleost TNFα shows some analogous functions with its mammalian counterparts, but the extent of its activities is still poorly understood. Cytokines are generally considered as a double-edge sword and TNFα has been implicated in the pathogenesis of different inflammatory diseases as well as in wasting syndromes described in mammals. The aim of this work was to analyse the expression of TNFα during enteromyxosis with molecular (Q-PCR) and morphological (immunohistochemistry) tools. Kidney, spleen and pyloric caeca from turbot with moderate and severe infections were analysed and compared to healthy naïve fish. TNFα expression was increased in both spleen and kidney in the earlier stages of the disease, whereas in severely infected fish, the expression decreased, especially in kidney. At the intestinal level, an increase in the number of TNFα-positive cells was noticed, which was proportional to the infiltration of inflammatory cells. The results demonstrate the involvement of TNFα in the immune response to E. scophthalmi in turbot, which could be related to the development of the clinic signs and lesions.
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Affiliation(s)
- Paolo Ronza
- Departamento de Ciencias Clínicas Veterinarias, Facultad de Veterinaria, Universidad de Santiago de Compostela, 27002, Lugo, Spain.
| | - Roberto Bermúdez
- Departamento de Anatomía y Producción Animal, Facultad de Veterinaria, Universidad de Santiago de Compostela, 27002, Lugo, Spain.
| | - Ana Paula Losada
- Departamento de Ciencias Clínicas Veterinarias, Facultad de Veterinaria, Universidad de Santiago de Compostela, 27002, Lugo, Spain.
| | - Ariadna Sitjà-Bobadilla
- Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, Castellón 12595, Spain.
| | - Belén G Pardo
- Departamento de Genética, Facultad de Veterinaria, Universidad de Santiago de Compostela, 27002, Lugo, Spain.
| | - María Isabel Quiroga
- Departamento de Ciencias Clínicas Veterinarias, Facultad de Veterinaria, Universidad de Santiago de Compostela, 27002, Lugo, Spain.
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28
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Guesdon W, Auray G, Pezier T, Bussière FI, Drouet F, Le Vern Y, Marquis M, Potiron L, Rabot S, Bruneau A, Werts C, Laurent F, Lacroix-Lamandé S. CCL20 Displays Antimicrobial Activity Against Cryptosporidium parvum, but Its Expression Is Reduced During Infection in the Intestine of Neonatal Mice. J Infect Dis 2015; 212:1332-40. [PMID: 25838265 DOI: 10.1093/infdis/jiv206] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 03/13/2015] [Indexed: 12/13/2022] Open
Abstract
CCL20 is a chemokine with antimicrobial activity. We investigated its expression and role during neonatal cryptosporidiosis, a worldwide protozoan enteric disease leading to severe diarrhea. Surprisingly, during infection by Cryptosporidium parvum, CCL20 production by the intestine of neonatal mice is reduced by a mechanism independent both of the enteric flora and of interferon γ, a key cytokine for the resolution of this infection. However, oral administration of recombinant CCL20 to neonatal mice significantly reduced the parasite load by a mechanism that was independent of immune cell recruitment and occurred instead by direct cytolytic activity on free stages of the parasite. MiR21 functionally targets CCL20 and is upregulated during the infection, thus contributing to the downregulation of the chemokine. Our findings demonstrate for the first time the direct antiparasitic activity of CCL20 against an enteric protozoan and its downregulation during C. parvum infection, which is detrimental to parasite clearance.
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Affiliation(s)
- William Guesdon
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Gaël Auray
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Tiffany Pezier
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Françoise I Bussière
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Françoise Drouet
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Yves Le Vern
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours INRA Val de Loire, Cytometry Platform
| | - Mathilde Marquis
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Laurent Potiron
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Sylvie Rabot
- INRA, UMR1319 Micalis AgroParisTech, UMR Micalis, Jouy-en-Josas
| | - Aurelia Bruneau
- INRA, UMR1319 Micalis AgroParisTech, UMR Micalis, Jouy-en-Josas
| | - Catherine Werts
- Unité Biologie et Génétique de la Paroi Bactérienne, Institut Pasteur, Paris, France
| | - Fabrice Laurent
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
| | - Sonia Lacroix-Lamandé
- INRA Val de Loire, UMR1282 Infectiologie et Santé Publique, Nouzilly Université François Rabelais, UMR1282 Infectiologie et Santé Publique, Tours
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29
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Robledo D, Ronza P, Harrison PW, Losada AP, Bermúdez R, Pardo BG, Redondo MJ, Sitjà-Bobadilla A, Quiroga MI, Martínez P. RNA-seq analysis reveals significant transcriptome changes in turbot (Scophthalmus maximus) suffering severe enteromyxosis. BMC Genomics 2014; 15:1149. [PMID: 25526753 PMCID: PMC4320470 DOI: 10.1186/1471-2164-15-1149] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 12/16/2014] [Indexed: 12/31/2022] Open
Abstract
Background Enteromyxosis caused by the intestinal myxozoan parasite Enteromyxum scophthalmi is a serious threat for turbot (Scophthalmus maximus, L.) aquaculture, causing severe catarrhal enteritis leading to a cachectic syndrome, with no therapeutic options available. There are still many aspects of host-parasite interaction and disease pathogenesis that are yet to be elucidated, and to date, no analysis of the transcriptomic changes induced by E. scophthalmi in turbot organs has been conducted. In this study, RNA-seq technology was applied to head kidney, spleen and pyloric caeca of severely infected turbot with the aim of furthering our understanding of the pathogenetic mechanisms and turbot immune response against enteromyxosis. Results A huge amount of information was generated with more than 23,000 identified genes in the three organs, amongst which 4,762 were differently expressed (DE) between infected and control fish. Associate gene functions were studied based on gene ontology terms and available literature, and the most interesting DE genes were classified into five categories: 1) immune and defence response; 2) apoptosis and cell proliferation; 3) iron metabolism and erythropoiesis; 4) cytoskeleton and extracellular matrix and 5) metabolism and digestive function. The analysis of down-regulated genes of the first category revealed evidences of a connexion failure between innate and adaptive immune response, especially represented by a high number of DE interferon-related genes in the three organs. Furthermore, we found an intense activation of local immune response at intestinal level that appeared exacerbated, whereas in kidney and spleen genes involved in adaptive immune response were mainly down-regulated. The apoptotic machinery was only clearly activated in pyloric caeca, while kidney and spleen showed a marked depression of genes related to erythropoiesis, probably related to disorders in iron homeostasis. The genetic signature of the causes and consequences of cachexia was also demonstrated by the down-regulation of the genes encoding structural proteins and those involved in the digestive metabolism. Conclusions This transcriptomic study has enabled us to gain a better understanding of the pathogenesis of enteromyxosis and identify a large number of DE target genes that bring us closer to the development of strategies designed to effectively combat this pathogen. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-1149) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | | | | | - María Isabel Quiroga
- Departamento de Ciencias Clínicas Veterinarias, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo 27002, Spain.
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30
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Pang T, Leach ST, Katz T, Day AS, Ooi CY. Fecal biomarkers of intestinal health and disease in children. Front Pediatr 2014; 2:6. [PMID: 24479111 PMCID: PMC3904282 DOI: 10.3389/fped.2014.00006] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/12/2014] [Indexed: 12/17/2022] Open
Abstract
The identification of various fecal biomarkers has provided insight into the intestinal milieu. Most of these markers are associated with the innate immune system of the gut, apart from the more novel M2-pyruvate kinase. The innate immunity of the gut plays a role in maintaining a fine balance between tolerance to commensal bacteria and immune response to potential pathogens. It is a complex system, which comprises of multiple elements, including antimicrobial peptides (e.g., defensins, cathelicidins, lactoferrin, and osteoprotegerin), inflammatory proteins (e.g., calprotectin and S100A12), and microbial products (e.g., short-chain fatty acids). Dysfunction of any component can lead to the development of intestinal disease, and different diseases have been associated with different fecal levels of these biomarkers. Each fecal biomarker provides information on specific biological and disease processes. Therefore, stool quantification of these biomarkers provides a non-invasive method to define potential pathways behind the pathogenesis of diseases and can assist in the assessment and diagnosis of various gastrointestinal conditions. The abovementioned fecal biomarkers and their role in intestinal health and disease will be reviewed in this paper with a pediatric focus.
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Affiliation(s)
- Tamara Pang
- Faculty of Medicine, School of Women's and Children's Health, University of New South Wales , Sydney, NSW , Australia
| | - Steven T Leach
- Faculty of Medicine, School of Women's and Children's Health, University of New South Wales , Sydney, NSW , Australia ; Department of Gastroenterology, Sydney Children's Hospital Randwick , Sydney, NSW , Australia
| | - Tamarah Katz
- Department of Nutrition and Dietetics, Sydney Children's Hospital , Sydney, NSW , Australia
| | - Andrew S Day
- Department of Paediatrics, University of Otago , Christchurch , New Zealand
| | - Chee Y Ooi
- Faculty of Medicine, School of Women's and Children's Health, University of New South Wales , Sydney, NSW , Australia ; Department of Gastroenterology, Sydney Children's Hospital Randwick , Sydney, NSW , Australia
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31
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Human primary intestinal epithelial cells as an improved in vitro model for Cryptosporidium parvum infection. Infect Immun 2013; 81:1996-2001. [PMID: 23509153 DOI: 10.1128/iai.01131-12] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The study of human intestinal pathogens has been limited by the lack of methods for the long-term culture of primary human intestinal epithelial cells (PECs). The development of infection models with PECs would allow a better understanding of host-parasite interactions. The objective of this study was to develop a novel method for prolonged in vitro cultivation of PECs that can be used to study Cryptosporidium infection. We isolated intact crypts from human intestines removed during weight loss surgery. The fragments of intestinal layers were cultivated with culture medium supplemented with growth factors and antiapoptotic molecules. After 7 days, the PECs formed self-regenerating cell clusters, forming villi that resemble intestinal epithelium. The PECs proliferated and remained viable for at least 60 days. The cells expressed markers for intestinal stem cells, epithelial cells, and mature enterocytes. The PECs were infected with Cryptosporidium. In contrast to older models in which parasite numbers decay, the burden of parasites increased for >120 h. In summary, we describe here a novel method for the cultivation of self-regenerating human epithelial cells from small intestinal crypts, which contain both intestinal stem cells and mature villus cells. We present data that suggest these cells support Cryptosporidium better than existing cell lines. PECs should provide an improved tool for studying host-parasite interactions involving Cryptosporidium and other intestinal pathogens.
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Abstract
The review provides current views on human protozoan parasites of the gut. The recognition of the importance of cryptosporidium, cyclospora and microsporidia over the last three decades emphasises the possibility that more pathogenic intestinal protozoa are presently unrecognized. Each of these is a zoonotic infection and the potential for a zoonotic element to the transmission of giardiasis has been recognized. A common theme in increased understanding of the biology and pathological mechanisms involved in causing disease is the application of molecular techniques to the various stages of the parasite life cycle. Molecular methods are increasingly contributing to laboratory diagnosis of these conditions with increased yields of positive results though in the tropics it is likely that fecal microscopy will remain the standard for some time to come. The nitroimidazole compounds are the mainstay of treatment for giardia and amebiasis with no major advance in therapeutics since their role was appreciated. Nitazoxanide was shown to be effective for cryptosporidiosis in the 1990s.
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Foster DM, Stauffer SH, Stone MR, Gookin JL. Proteasome inhibition of pathologic shedding of enterocytes to defend barrier function requires X-linked inhibitor of apoptosis protein and nuclear factor κB. Gastroenterology 2012; 143:133-44.e4. [PMID: 22446197 DOI: 10.1053/j.gastro.2012.03.030] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 03/07/2012] [Accepted: 03/12/2012] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS Although we are beginning to understand where, when, and how intestinal epithelial cells are shed, physiologically, less is understood about alterations in cell fate during minimally invasive epithelial infections. We used a piglet model of Cryptosporidium parvum infection to determine how elimination of infected enterocytes is balanced with the need to maintain barrier function. METHODS We studied the effects of enterocyte shedding by C parvum-infected ileum on barrier function ex vivo with Ussing chambers. The locations and activities of caspase-3, nuclear factor κB (NF-κB), and inhibitor of apoptosis proteins (IAP) were assayed by enzyme-linked immunosorbent assay, immunoblot, and tissue immunoreactivity analyses and using specific pharmacologic inhibitors. The location, specificity, and magnitude of enterocyte shedding were quantified using special stains and light microscopy. RESULTS Infection with C parvum activated apoptotic signaling pathways in enterocytes that resulted in cleavage of caspase-3. Despite caspase-3 cleavage, enterocyte shedding was confined to villus tips, coincident with apoptosis, and observed more frequently in infected cells. Epithelial expression of X-linked inhibitor of apoptosis protein (XIAP), activation of NF-κB, and proteasome activity were required for control of cell shedding and barrier function. The proteasome blocked activity of caspase-3; this process was mediated by expression of XIAP, which bound to cleaved caspase-3. CONCLUSIONS We have identified a pathway by which villus epithelial cells are maintained during C parvum infection. Loss of barrier function is reduced by active retention of infected enterocytes until they reach the villus tip. These findings might be used to promote clearance of minimally invasive enteropathogens, such as by increasing the rate of migration of epithelial cells from the crypt to the villus tip.
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Affiliation(s)
- Derek M Foster
- Department of Population Health, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina 27607, USA
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34
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O'Hara SP, Chen XM. The cell biology of cryptosporidium infection. Microbes Infect 2011; 13:721-30. [PMID: 21458585 DOI: 10.1016/j.micinf.2011.03.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 03/23/2011] [Indexed: 01/13/2023]
Abstract
Cryptosporidiosis remains a significant cause of enteric disease worldwide. Basic investigations of host: pathogen interactions have revealed the intricate processes mediating infection. The following summarizes the interactions that mediate infection and the host responses that both permit and ultimately clear the infection.
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Affiliation(s)
- Steven P O'Hara
- Center for Basic Research in Digestive Diseases, Division of Gastroenterology and Hepatology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
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Pantenburg B, Castellanos-Gonzalez A, Dann SM, Connelly RL, Lewis DE, Ward HD, White AC. Human CD8(+) T cells clear Cryptosporidium parvum from infected intestinal epithelial cells. Am J Trop Med Hyg 2010; 82:600-7. [PMID: 20348507 DOI: 10.4269/ajtmh.2010.09-0590] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Intracellular protozoans of the genus Cryptosporidium are a major cause of diarrheal illness worldwide, especially in immunocompromised individuals. CD4(+) T cells and interferon-gamma are key factors in the control of cryptosporidiosis in human and murine models. Previous studies led us to hypothesize that CD8(+) T cells contribute to clearance of intestinal epithelial Cryptosporidium infection in humans. We report here that antigen expanded sensitized CD8(+) T cells reduce the parasite load in infected intestinal epithelial cell cultures and lyse infected intestinal epithelial cells. These effects are most likely mediated by the release of cytotoxic granules. Elimination of parasites seems to require antigen presentation through both human leukocyte antigen (HLA)-A and HLA-B. These data suggest that cytotoxic CD8(+) T cells play a role in clearing Cryptosporidium from the intestine, a previously unrecognized feature of the human immune response against this parasite.
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Affiliation(s)
- Birte Pantenburg
- Division of Infectious Diseases, Department of Internal Medicine, Department of Microbiology, University of Texas Medical Branch, Galveston, Texas, USA.
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Cell sorting-assisted microarray profiling of host cell response to Cryptosporidium parvum infection. Infect Immun 2009; 78:1040-8. [PMID: 20038534 DOI: 10.1128/iai.01009-09] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To study the transcriptional response of mammalian cells to infection with the intracellular apicomplexan parasite Cryptosporidium parvum, infected and uninfected cells were recovered from C. parvum-infected cell monolayers. This approach, which contrasts with a more conventional experimental design that compares infected to uninfected cell monolayers, enabled the identification of functional categories of genes that are differentially transcribed as a direct consequence of the presence of intracellular parasites. Among several categories of upregulated genes, glycoprotein metabolism was significantly overrepresented. To investigate whether these transcriptional changes affected the composition of the surface of infected cells, cells were probed with fluorescently labeled lectins. Among a panel of seven lectins, soybean agglutinin, which recognizes N-acetyl-d-galactosamine, generated the largest difference in fluorescence between infected and uninfected cells. The origin of the fluorescent signal emitted by infected cells was further investigated and attributed to the overexpression of glycoprotein on the surface of infected cells, as well as the presence of glycoprotein located in the proximity of intracellular parasites.
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Yang YL, Serrano MG, Sheoran AS, Manque PA, Buck GA, Widmer G. Over-expression and localization of a host protein on the membrane of Cryptosporidium parvum infected epithelial cells. Mol Biochem Parasitol 2009; 168:95-101. [PMID: 19631240 PMCID: PMC2752322 DOI: 10.1016/j.molbiopara.2009.07.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 06/26/2009] [Accepted: 07/13/2009] [Indexed: 12/30/2022]
Abstract
The genus Cryptosporidium includes several species of intestinal protozoan parasites which multiply in intestinal epithelial cells. The impact of this infection on the transcriptome of cultured host cells was investigated using DNA microarray hybridizations. The expression of 14 genes found to be consistently up- or down-regulated in infected cell monolayers was validated with RT PCR. Using immunofluorescence we examined the expression of Protease Activated Receptor-2, which is encoded by one of the up-regulated genes. In infected cells this receptor localized to the host cell membrane which covers the intracellular trophozoites and meronts. This observation indicates that the composition of the host cell membrane is affected by the developing trophozoite, a phenomenon which has not been described previously.
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Affiliation(s)
- Yi-Lin Yang
- Tufts Cummings School of Veterinary Medicine, Division of Infectious Diseases, 200 Westboro Road, North Grafton, MA 01536, USA
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Ortega-Pierres G, Smith HV, Cacciò SM, Thompson RA. New tools provide further insights into Giardia and Cryptosporidium biology. Trends Parasitol 2009; 25:410-6. [DOI: 10.1016/j.pt.2009.06.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Revised: 06/02/2009] [Accepted: 06/12/2009] [Indexed: 12/12/2022]
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Mohamed JA, DuPont HL, Jiang ZD, Flores J, Carlin LG, Belkind-Gerson J, Martinez-Sandoval FG, Guo D, White AC, Okhuysen PC. A single-nucleotide polymorphism in the gene encoding osteoprotegerin, an anti-inflammatory protein produced in response to infection with diarrheagenic Escherichia coli, is associated with an increased risk of nonsecretory bacterial diarrhea in North American travelers to Mexico. J Infect Dis 2009; 199:477-85. [PMID: 19128145 DOI: 10.1086/596319] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Osteoprotegerin (OPG), an immunoregulatory member of the TNF receptor superfamily, is expressed in inflamed intestinal mucosa. We investigated whether OPG is produced by intestinal epithelial cells and tested the hypothesis that single-nucleotide polymorphisms (SNPs) in the gene encoding OPG (TNFRSF11B) are associated with traveler's diarrhea (TD) among North American travelers to Mexico. METHODS OPG concentration was measured in the supernatants of T84 cells infected with various diarrheagenic Escherichia coli pathotypes. Genotyping was performed for 4 SNPs in the OPG gene for 968 North American travelers with or without TD. Stool samples from travelers with TD were evaluated for the presence of enteric pathogens. RESULTS T84 cells produced higher OPG levels in response to infection with various diarrheagenic E. coli pathotypes than with E. coli controls (P<.05). A SNP in the exon 1 region of the OPG gene (OPG+1181G>C) was associated with TD in white travelers who stayed in Mexico for >1 week during the summer (P=.009) and for TD due to nonsecretory pathogens (P=.001). CONCLUSIONS Our study suggests that OPG is secreted by intestinal epithelial cells in response to enteropathogens and that a polymorphism in the OPG gene is associated with an increased susceptibility to TD.
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Affiliation(s)
- Jamal A Mohamed
- Division of Infectious Diseases, The University of Texas Medical School, Center for Infectious Diseases, Baylor College of Medicine, Houston, TX, USA
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