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Lozano-Mendoza J, Ramírez-Montiel F, Rangel-Serrano Á, Páramo-Pérez I, Mendoza-Macías CL, Saavedra-Salazar F, Franco B, Vargas-Maya N, Jeelani G, Saito-Nakano Y, Anaya-Velázquez F, Nozaki T, Padilla-Vaca F. Attenuation of In Vitro and In Vivo Virulence Is Associated with Repression of Gene Expression of AIG1 Gene in Entamoeba histolytica. Pathogens 2023; 12:pathogens12030489. [PMID: 36986411 PMCID: PMC10051847 DOI: 10.3390/pathogens12030489] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 02/27/2023] [Accepted: 03/02/2023] [Indexed: 03/30/2023] Open
Abstract
Entamoeba histolytica virulence results from complex host-parasite interactions implicating multiple amoebic components (e.g., Gal/GalNAc lectin, cysteine proteinases, and amoebapores) and host factors (microbiota and immune response). UG10 is a strain derived from E. histolytica virulent HM-1:IMSS strain that has lost its virulence in vitro and in vivo as determined by a decrease of hemolytic, cytopathic, and cytotoxic activities, increased susceptibility to human complement, and its inability to form liver abscesses in hamsters. We compared the transcriptome of nonvirulent UG10 and its parental HM-1:IMSS strain. No differences in gene expression of the classical virulence factors were observed. Genes downregulated in the UG10 trophozoites encode for proteins that belong to small GTPases, such as Rab and AIG1. Several protein-coding genes, including iron-sulfur flavoproteins and heat shock protein 70, were also upregulated in UG10. Overexpression of the EhAIG1 gene (EHI_180390) in nonvirulent UG10 trophozoites resulted in augmented virulence in vitro and in vivo. Cocultivation of HM-1:IMSS with E. coli O55 bacteria cells reduced virulence in vitro, and the EhAIG1 gene expression was downregulated. In contrast, virulence was increased in the monoxenic strain UG10, and the EhAIG1 gene expression was upregulated. Therefore, the EhAIG1 gene (EHI_180390) represents a novel virulence determinant in E. histolytica.
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Affiliation(s)
- Janeth Lozano-Mendoza
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - Fátima Ramírez-Montiel
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - Ángeles Rangel-Serrano
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - Itzel Páramo-Pérez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | | | - Faridi Saavedra-Salazar
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - Bernardo Franco
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - Naurú Vargas-Maya
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - Ghulam Jeelani
- Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan
| | - Yumiko Saito-Nakano
- Department of Parasitology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-0052, Japan
| | - Fernando Anaya-Velázquez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - Tomoyoshi Nozaki
- Graduate School of Medicine, The University of Tokyo, Tokyo 113-8654, Japan
- Department of Parasitology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-0052, Japan
| | - Felipe Padilla-Vaca
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato 36050, Mexico
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Singh A, Banerjee T. Host-parasite interactions in infections due to Entamoeba histolytica: A tale of known and unknown. Trop Parasitol 2022; 12:69-77. [PMID: 36643990 PMCID: PMC9832491 DOI: 10.4103/tp.tp_81_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 11/17/2021] [Accepted: 12/07/2021] [Indexed: 11/25/2022] Open
Abstract
Entamoeba histolytica (E. histolytica) is an enteric microaerophilic protozoan parasite responsible for millions of cases worldwide. Majority of the infections due to E. histolytica remain asymptomatic; however, it can cause an array of symptoms ranging from devastating dysentery, colitis, and abscesses in different vital organs. The interactions between the E. histolytica and its host are a multifaceted chain of events rather than merely destruction and invasion. There are manifold decisive steps for the establishment of infections by E. histolytica which includes degradation of mucosal layer, adherence to the host epithelium, invasion into the host tissues, and dissemination to vital organs. It is widely hypothesized that, for establishment of infections, the interactions at the intestinal mucosa decides the fate of the disease. The delicate communications between the parasite, the host factors, and the associated bacterial microflora play a significant role in the pathogenesis of E. histolytica. In this review, we summarize the interactions between the E. histolytica and it's host at the genetic and immunological interphases emphasizing the crucial role of microbiota in these interactions.
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Affiliation(s)
- Aradhana Singh
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
| | - Tuhina Banerjee
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
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Possible role played by the SINE2 element in gene regulation, as demonstrated by differential processing and polyadenylation in avirulent strains of E. histolytica. Antonie van Leeuwenhoek 2021; 114:209-221. [PMID: 33394209 DOI: 10.1007/s10482-020-01504-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 11/25/2020] [Indexed: 10/22/2022]
Abstract
Entamoeba histolytica represents a useful model in parasitic organisms due to its complex genomic organization and survival mechanisms. To counteract pathogenic organisms, it is necessary to characterize their molecular biology to design new strategies to combat them. In this report, we investigated a less-known genetic element, short interspersed nuclear element 2 (SINE2), that is present in this ameba and is highly transcribed and polyadenylated. In this study, we show that in two different nonvirulent strains of E. histolytica, SINE2 is differentially processed into two transcript fragments, that is, a full-length 560-nt fragment and a shorter 393-nt fragment bearing an approximately 18-nt polyadenylation tail. Sequence analysis of the SINE2 transcript showed that a Musashi-like protein may bind to it. Also, two putative Musashi-like sequences were identified on the transcript. Semiquantitative expression analysis of the two Musashi-like proteins identified in the E. histolytica genome (XP_648918 and XP_649094) showed that XP_64094 is overexpressed in the nonvirulent strains tested. The information available in the literature and the results presented in this report indicate that SINE2 may affect other genes, as observed with the epigenetic silencing of the G3 strain, by an antisense mechanism or via RNA-protein interactions that may ultimately be involved in the phenotype of nonvirulent strains of E. histolytica.
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Urquieta-Ramírez L, Ramírez-Montiel F, Andrade-Guillén S, Páramo-Pérez I, Rangel-Serrano Á, Reyes-Cortes R, Franco B, Mendoza-Macías CL, Anaya-Velázquez F, Padilla-Vaca F. Contribution of neutral sphingomyelinases to in vitro virulence of Entamoeba histolytica. Exp Parasitol 2018; 194:38-44. [PMID: 30253133 DOI: 10.1016/j.exppara.2018.09.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 06/08/2018] [Accepted: 09/20/2018] [Indexed: 12/14/2022]
Abstract
Amoebiasis is a worldwide health problem caused by the pathogen Entamoeba histolytica. Several virulence factors have been implicated in host invasion, immune evasion, and tissue damage. There are still new factors that remain to be elucidated and characterized. In this work, we obtained amoebic transfectants overexpressing three of the neutral sphingomyelinase enzymes encoded in the E. histolytica genome. The EhnSM3 overexpression induced an increase in hemolytic and cytotoxic activities, besides an increase in gene expression of amoebapore A, B, and C. Meanwhile the EhnSM1 and EhnSM2 overexpression caused an increase in cytopathic activity. In all the neutral sphingomyelinases overexpressing strains, the gene expression levels for cysteine proteinase 5, adhesin 112 and, heavy and light Gal/GalNAc lectin subunits were not affected. We propose that the increase of cytotoxic and lytic effect of EhnSM3 overexpressed strain can be related to the sum of the effect of EhnSM3 plus amoebapores, in a process cell contact-dependent or as mediator by inducing the gene expression of amoebapores enabling a link between EhnSM3 with the virulence phenotype in E. histolytica. Our results suggest a differential role for neutral sphingomyelinases in E. histolytica virulence.
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Affiliation(s)
- Luz Urquieta-Ramírez
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Fátima Ramírez-Montiel
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Sairy Andrade-Guillén
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Itzel Páramo-Pérez
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Ángeles Rangel-Serrano
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Ruth Reyes-Cortes
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Bernardo Franco
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Claudia Leticia Mendoza-Macías
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico
| | - Fernando Anaya-Velázquez
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico.
| | - Felipe Padilla-Vaca
- Departamento de Biología y Departamento de Farmacia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto, 36050, Mexico.
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5
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Delgado-Galván CJ, Padilla-Vaca F, Montiel FBR, Rangel-Serrano Á, Paramo-Pérez I, Anaya-Velázquez F, Franco B. Red fluorescent protein (DsRFP) optimization for Entamoeba histolytica expression. Exp Parasitol 2018; 187:86-92. [PMID: 29476758 DOI: 10.1016/j.exppara.2018.01.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 01/05/2018] [Accepted: 01/30/2018] [Indexed: 12/01/2022]
Abstract
Entamoeba histolytica genetic organization and genome structure is complex and under intense research. The genome is fully sequenced, and several tools have been developed for the molecular study of this organism. Nevertheless, good protein tracking tags that are easy to measure and image, like the fluorescent proteins are lacking. In this report, we codon-optimized the red fluorescent protein from the coral Discosoma striata (DsRFP) for its use in E. histolytica and demonstrated functionality in vivo. We envision that this protein can be widely used for the development of transcriptional reporter systems and protein-tagging applications.
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Affiliation(s)
- Cindy Jazmín Delgado-Galván
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, Mexico
| | - Felipe Padilla-Vaca
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, Mexico
| | - Fátima Berenice Ramírez Montiel
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, Mexico
| | - Ángeles Rangel-Serrano
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, Mexico
| | - Itzel Paramo-Pérez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, Mexico
| | - Fernando Anaya-Velázquez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, Mexico
| | - Bernardo Franco
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, Mexico.
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Verma K, Nozaki T, Datta S. Role of EhRab7A in phagocytosis of type 1 fimbriated E. coli by Entamoeba histolytica. Mol Microbiol 2016; 102:1043-1061. [PMID: 27663892 DOI: 10.1111/mmi.13533] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2016] [Indexed: 01/16/2023]
Abstract
Entamoeba histolytica, the causative agent of amoebic colitis and liver abscess in human, ingests the intestinal bacteria and variety of host cells. Phagocytosis of bacteria by the amebic trophozoite has been reported to be important for the virulence of the parasite. Here, we set out to characterize different stages of phagocytosis of type 1 E. coli and investigated the role of a set of amoebic Rab GTPases in the process. The localizations of the Rab GTPases during different stages of the phagocytosis were investigated using laser scanning confocal microscopy and their functional relevance were determined using fluorescence activated cell sorter based assay as well as colony forming unit assay. Our results demonstrate that EhRab7A is localized on the phagosomes and involved in both early and late stages of type 1 E. coli phagocytosis. We further showed that the E. coli or RBC containing phagosomes are distinct from the large endocytic vacuoles in the parasite which are exclusively used to transport human holotransferrin and low density lipoprotein. Remarkably, type 1 E. coli uptake was found to be insensitive to cytochalasin D treatment, suggesting that the initial stage of E. coli phagocytosis is independent of the formation of actin filaments.
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Affiliation(s)
- Kuldeep Verma
- Department of Biological Science, Indian Institute of Science Education and Research Bhopal Bypass Road, Bhauri, Bhopal, 462 066, Madhya Pradesh, India
| | - Tomoyoshi Nozaki
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, 162-8640, Japan
| | - Sunando Datta
- Department of Biological Science, Indian Institute of Science Education and Research Bhopal Bypass Road, Bhauri, Bhopal, 462 066, Madhya Pradesh, India
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Lachish T, Wieder-Finesod A, Schwartz E. Amebic Liver Abscess in Israeli Travelers: A Retrospective Study. Am J Trop Med Hyg 2016; 94:1015-9. [PMID: 26928829 DOI: 10.4269/ajtmh.15-0576] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 12/14/2015] [Indexed: 01/21/2023] Open
Abstract
Amebic liver abscess (ALA) is endemic in developing countries. The epidemiology and clinical characteristics of the disease in developing countries are well described. Travelers from nonendemic countries can serve as a model for the natural history of ALA. Currently, the available literature on travelers is limited. This is a retrospective observational study on Israeli travelers diagnosed with ALA. Data regarding travel history, clinical presentation, imaging, and treatment were collected and analyzed. Among 6,867 ill returning Israeli travelers, amebiasis was diagnosed in 53 travelers (0.77%), of whom 14 were with ALA (0.2%). Twelve ALA cases (86%) had an exposure in the Indian subcontinent. The male to female ratio was 1:1, with no significant clinical differences between the sexes. The average lag period between exposure and onset of symptoms was 17.1 months. The lack of male predominance and the prolonged lag period may imply that behavioral factors are pivotal in the development of ALA. Larger case series of travelers are required.
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Affiliation(s)
- Tamar Lachish
- Infectious Diseases Unit, Shaare-Zedek Medical Center, Jerusalem, Israel; Infectious Diseases Unit, Sheba Medical Center, Tel Hashomer, Israel; The Center for Geographic Medicine, The Chaim Sheba Medical Center, Tel Hashomer, Israel; The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Anat Wieder-Finesod
- Infectious Diseases Unit, Shaare-Zedek Medical Center, Jerusalem, Israel; Infectious Diseases Unit, Sheba Medical Center, Tel Hashomer, Israel; The Center for Geographic Medicine, The Chaim Sheba Medical Center, Tel Hashomer, Israel; The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Eli Schwartz
- Infectious Diseases Unit, Shaare-Zedek Medical Center, Jerusalem, Israel; Infectious Diseases Unit, Sheba Medical Center, Tel Hashomer, Israel; The Center for Geographic Medicine, The Chaim Sheba Medical Center, Tel Hashomer, Israel; The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Bär AK, Phukan N, Pinheiro J, Simoes-Barbosa A. The Interplay of Host Microbiota and Parasitic Protozoans at Mucosal Interfaces: Implications for the Outcomes of Infections and Diseases. PLoS Negl Trop Dis 2015; 9:e0004176. [PMID: 26658061 PMCID: PMC4684208 DOI: 10.1371/journal.pntd.0004176] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Infections by parasitic protozoans are largely neglected, despite threatening millions of people, particularly in developing countries. With descriptions of the microbiota in humans, a new frontier of investigation is developing to decipher the complexity of host-parasite-microbiota relationships, instead of the classic reductionist approach, which considers host-parasite in isolation. Here, we review with specific examples the potential roles that the resident microbiota can play at mucosal interfaces in the transmission of parasitic protozoans and in the progress of infection and disease. Although the mechanisms underlying these relationships remain poorly understood, some examples provide compelling evidence that specific components of the microbiota can potentially alter the outcomes of parasitic infections and diseases in humans. Most findings suggest a protective role of the microbiota, which might lead to exploratory research comprising microbiota-based interventions to prevent and treat protozoal infections in the future. However, these infections are often accompanied by an unbalanced microbiota and, in some specific cases, apparently, these bacteria may contribute synergistically to disease progression. Taken together, these findings provide a different perspective on the ecological nature of protozoal infections. This review focuses attention on the importance of considering polymicrobial associations, i.e., parasitic protozoans and the host microbiota, for understanding these human infections in their natural microbial context.
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Affiliation(s)
- Ann-Katrein Bär
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Niha Phukan
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Jully Pinheiro
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Augusto Simoes-Barbosa
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
- Centre for Microbial Innovation, University of Auckland, Auckland, New Zealand
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9
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He GZ, Deng SX, Tian WY, Feng Y. Evaluation of the efficacy of a recombinant Entamoeba histolytica cysteine proteinase gene (EhCP5) antigen in Minipig. Exp Parasitol 2011; 130:253-6. [PMID: 22202181 DOI: 10.1016/j.exppara.2011.12.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 12/09/2011] [Accepted: 12/13/2011] [Indexed: 12/31/2022]
Abstract
Entamoeba histolytica cysteine proteinase gene 5(EhCP5) is one of the major proteinase genes of all EhCP-transcripts. The amebiasis cysteine proteinase gene encoding an antigen from E. histolytica, as well as the recombinant EhCP5, obtained by cloning and expression of the EhCP5 gene in heterologous host Escherichia coli BL-21 (DE3), were used to evaluate their ability to induce immune protective responses in Minipig against challenge infection in a minipig-E. histolytica model. There was a 52.27% reduction (P<0.001) in the group of recovery of challenged E. histolytica compared with that in the control group. Specific anti-EhCP5 antibodies from immune protected minipig had significantly higher levels of immunoglobulin G (IgG) (P<0.0001). Our data will help to know the mechanism of vaccinal protection of E. histolytica.
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Affiliation(s)
- Guang-Zhi He
- Guiyang College of Traditional Chinese Medicine, Guiyang 550002, Guizhou Province, China.
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10
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Anaya-Velázquez F, Padilla-Vaca F. Virulence of Entamoeba histolytica: a challenge for human health research. Future Microbiol 2011; 6:255-8. [DOI: 10.2217/fmb.11.2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
| | - Felipe Padilla-Vaca
- Departamento de Biología, División de CNE, Universidad de Guanajuato, Noria Alta s/n, Guanajuato, Gto. 36050, México
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11
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Mendoza-Macías CL, Barrios-Ceballos MP, Anaya-Velázquez F, Nakada-Tsukui K, Nozaki T, Padilla-Vaca F. Entamoeba histolytica: Molecular cloning and characterization of a novel neutral sphingomyelinase. Exp Parasitol 2010; 125:279-85. [DOI: 10.1016/j.exppara.2010.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Revised: 01/28/2010] [Accepted: 02/01/2010] [Indexed: 01/21/2023]
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12
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Singer M. Pathogen-pathogen interaction: a syndemic model of complex biosocial processes in disease. Virulence 2010; 1:10-8. [PMID: 21178409 PMCID: PMC3080196 DOI: 10.4161/viru.1.1.9933] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 08/24/2009] [Accepted: 08/27/2009] [Indexed: 11/19/2022] Open
Abstract
There is growing awareness of the health implications of fact that infectious agents often do not act independently; rather their disease potential is mediated in diverse and significant ways by their relationships with other pathogens. Pathogen-pathogen interaction (PPI), for example, impacts various virulence factors in human infection. Although still in its infancy, the study of PPI, a form of epidemiological synergism, is emerging as an important arena of new research and new understanding in health and clinical care. The aims of this paper are to: 1) draw attention to the role of PPI in human disease patterns; 2) present the syndemics model as a biosocial approach for examining the nature, pathways, contexts, and health implications of PPI; and 3) suggest the utility of this approach to PPI. Toward these ends, this paper (a) reviews three of case examples of alternative PPIs, (b) describes the development and key concepts and components of the syndemics model with specific reference to interacting infectious agents, (c) contextualizes this discussion with a brief review of broader syndemics disease processes (not necessarily involving infections disease), and (d) comments on the research, treatment and prevention implications of syndemic interaction among pathogens.
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Affiliation(s)
- Merrill Singer
- University of Connecticut, Center for Health, Intervention and Prevention, Storrs, CT, USA.
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