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Redondo N, Navarro D, Aguado JM, Fernández-Ruiz M. Viruses, friends and foes: The case of Torque Teno virus and the net state of immunosuppression. Transpl Infect Dis 2021; 24:e13778. [PMID: 34933413 DOI: 10.1111/tid.13778] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/16/2021] [Accepted: 12/05/2021] [Indexed: 11/30/2022]
Abstract
New reliable biomarkers are needed to improve individual risk assessment for post-transplant infection, acute graft rejection and other immune-related complications after solid organ transplantation (SOT) and allogeneic hematopoietic stem cell transplantation (allo-HSCT). One promising strategy relies on the monitoring of replication kinetics of virome components as functional surrogate for the net state of immunosuppression. Torque Teno Virus (TTV) is a small, non-enveloped, circular, single-stranded DNA anellovirus with no attributable pathological effects. A major component of the human blood virome, TTV exhibits various features that facilitate its application as immune biomarker: high prevalence rates, nearly ubiquitous distribution, stable viral loads with little intra-individual variability, insensitivity to antiviral drugs, and availability of commercial PCR assays for DNA quantification. The present review summarizes the available studies supporting the use of post-transplant TTV viremia to predict patient and graft outcomes after SOT and allo-HSCT. Taken together, this evidence suggests that high or increasing TTV DNA levels precede the occurrence of infectious complications in the SOT setting, whereas low or decreasing viral loads are associated with the development of acute rejection. The interpretation in allo-HSCT recipients is further complicated by complex interplay with the underlying disease, conditioning regimen and timing of recovery of lymphocyte counts, although TTV kinetics may act as a marker of immunological reconstitution at the early post-transplant period. The standardization of PCR methods and reporting units for TTV DNAemia and the results from ongoing interventional trials evaluating a TTV load-guided strategy to adjust immunosuppressive therapy are achievements expected in the coming years. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Natalia Redondo
- Unit of Infectious Diseases, Hospital Universitario "12 de Octubre", Instituto de Investigación Sanitaria Hospital "12 de Octubre" (imas12), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, Spain
| | - David Navarro
- Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, Spain.,Department of Microbiology, Hospital Clínico Universitario, Instituto de Investigación Sanitaria INCLIVA, Valencia, Spain.,Department of Microbiology, School of Medicine, University of Valencia, Valencia, Spain
| | - José María Aguado
- Unit of Infectious Diseases, Hospital Universitario "12 de Octubre", Instituto de Investigación Sanitaria Hospital "12 de Octubre" (imas12), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, Spain.,Department of Medicine, School of Medicine, Universidad Complutense, Madrid, Spain
| | - Mario Fernández-Ruiz
- Unit of Infectious Diseases, Hospital Universitario "12 de Octubre", Instituto de Investigación Sanitaria Hospital "12 de Octubre" (imas12), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, Spain.,Department of Medicine, School of Medicine, Universidad Complutense, Madrid, Spain
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Lapa D, Del Porto P, Minosse C, D’Offizi G, Antinori A, Capobianchi MR, Visco-Comandini U, McPhee F, Garbuglia AR, Zaccarelli M. Clinical Relevance of Torque Teno Virus (TTV) in HIV/HCV Coinfected and HCV Monoinfected Patients Treated with Direct-Acting Antiviral Therapy. J Clin Med 2021; 10:jcm10102092. [PMID: 34068071 PMCID: PMC8152458 DOI: 10.3390/jcm10102092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/02/2021] [Accepted: 05/06/2021] [Indexed: 02/07/2023] Open
Abstract
Torque Teno virus (TTV) is a ubiquitous virus that causes chronic infection in humans with unknown clinical consequences. Here, we investigated the influence of TTV infection on HCV direct-acting antiviral (DAA) efficacy in HIV/HCV coinfected and HCV monoinfected patients as controls. Of 92 study patients, 79.3% were TTV DNA positive; untreated patients exhibited a significantly higher proportion of TTV DNA-positivity vs. sustained virological response (SVR) patients (100.0% vs. 65.2%, p < 0.001), while TTV positivity was not significant in DAA failure patients vs. SVR patients despite HIV/HCV coinfection. TTV DNA viral load was higher among HCV monoinfected patients vs. HIV/HCV coinfected, although marginally significant (p = 0.074) and no significant viral load difference was detected between DAA failures and SVR patients, while untreated vs. SVR patients had a significantly higher viral load (19,884, IQR 5977–333,534, vs. 469, IQR 10–4124, p = 0.004). Alpha-genogroup 3 TTV was the most prevalent genetic group, and no specific strain or genogroup was observed in relapser patients. Among HIV/HCV patients with HCV RNA detectable at end of treatment (EOT), TTV DNA was detected in 9/17 treatment responder patients and 3/5 relapser patients, thus, TTV infection does not appear to influence the control HCV viremia after EOT. Levels of IL-6 IL-4, and CD14 were not significantly different between TTV PCR-positive and -negative patients. These results suggest no association between TTV DNA positivity or viral load and HCV DAA failure whether patients were HIV/HCV coinfected or HCV monoinfected.
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Affiliation(s)
- Daniele Lapa
- Laboratory of Virology, “Lazzaro Spallanzani” National Institute for Infectious Diseases, IRCCS, 00149 Rome, Italy; (D.L.); (C.M.); (M.R.C.)
| | - Paola Del Porto
- Department of Biology and Biotechnology “C. Darwin”, Sapienza University, 00185 Rome, Italy;
| | - Claudia Minosse
- Laboratory of Virology, “Lazzaro Spallanzani” National Institute for Infectious Diseases, IRCCS, 00149 Rome, Italy; (D.L.); (C.M.); (M.R.C.)
| | - Gianpiero D’Offizi
- Hepatology and Infectious Diseases Unit, “Lazzaro Spallanzani” National Institute for Infectious Diseases IRCCS, 00149 Rome, Italy; (G.D.); (U.V.-C.)
| | - Andrea Antinori
- Clinical Department, “Lazzaro Spallanzani ” National Institute for Infectious Diseases, IRCCS, 00149 Rome, Italy; (A.A.); (M.Z.)
| | - Maria Rosaria Capobianchi
- Laboratory of Virology, “Lazzaro Spallanzani” National Institute for Infectious Diseases, IRCCS, 00149 Rome, Italy; (D.L.); (C.M.); (M.R.C.)
| | - Ubaldo Visco-Comandini
- Hepatology and Infectious Diseases Unit, “Lazzaro Spallanzani” National Institute for Infectious Diseases IRCCS, 00149 Rome, Italy; (G.D.); (U.V.-C.)
| | | | - Anna Rosa Garbuglia
- Laboratory of Virology, “Lazzaro Spallanzani” National Institute for Infectious Diseases, IRCCS, 00149 Rome, Italy; (D.L.); (C.M.); (M.R.C.)
- Correspondence: ; Tel.: +39-06-5517-0692; Fax: +39-06-559-455
| | - Mauro Zaccarelli
- Clinical Department, “Lazzaro Spallanzani ” National Institute for Infectious Diseases, IRCCS, 00149 Rome, Italy; (A.A.); (M.Z.)
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Xie Y, Xue Q, Jiao W, Wu J, Yu Y, Zhao L, Xu Y, Deng X, Fang G, Zheng Y, Gao Z. Associations Between Sputum Torque Teno Virus Load and Lung Function and Disease Severity in Patients With Chronic Obstructive Pulmonary Disease. Front Med (Lausanne) 2021; 8:618757. [PMID: 33968949 PMCID: PMC8100204 DOI: 10.3389/fmed.2021.618757] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 03/25/2021] [Indexed: 12/15/2022] Open
Abstract
Purpose: Viral load of Torque Teno virus (TTV) is elevated in immunosuppressed patients. The weakened immune response is typical in chronic obstructive pulmonary disease (COPD) patients. However, the relationship between TTV and COPD is still unknown. Patients and Methods: We enrolled 91 patients admitted to hospitals with acute exacerbation of COPD (AECOPD) between January 2017 and August 2017 (ClinicalTrials.gov ID, NCT03236480). Sputum samples were gathered during hospitalization and the 120-day follow-up. TTV distribution and genogroups were assessed, and the associations between viral loads and clinical parameters were analyzed. Results: TTV DNA was detected in 95.6% of COPD patients, and the viral load was nearly invariable at the stable and exacerbation states. Most TTV DNA-positive patients carried four distinct genotypes. Sputum load of TTV was positively associated with RV/TLC (r = 0.378, p = 0.030), and negatively correlated with FEV1/pre and FEV1/FVC (r = −0.484, −0.432, p = 0.011, 0.024, respectively). Neutral correlation between the TTV DNA load and COPD assessment test (CAT) scores (r = 0.258, p = 0.018) was observed. Conclusion: Sputum loads of TTV DNA could be a novel indicator for lung function and disease severity assessment in COPD patients.
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Affiliation(s)
- Yu Xie
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China
| | - Qing Xue
- Department of Pulmonary and Critical Care Medicine, Ningde Municipal Hospital Affiliated to Fujian Medical University, Ningde, China
| | - Weike Jiao
- Department of Pulmonary and Critical Care Medicine, Ningde Municipal Hospital Affiliated to Fujian Medical University, Ningde, China
| | - Jianhui Wu
- Department of Pulmonary and Critical Care Medicine, Ningde Municipal Hospital Affiliated to Fujian Medical University, Ningde, China
| | - Yan Yu
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China
| | - Lili Zhao
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China
| | - Yu Xu
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China
| | - Xinyu Deng
- Department of Pulmonary and Critical Care Medicine, Ningde Municipal Hospital Affiliated to Fujian Medical University, Ningde, China
| | - Guiju Fang
- Department of Pulmonary and Critical Care Medicine, Ningde Municipal Hospital Affiliated to Fujian Medical University, Ningde, China
| | - Yali Zheng
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China.,Department of Respiratory, Critical Care, and Sleep Medicine, Xiang'an Hospital of Xiamen University, Xiamen, China
| | - Zhancheng Gao
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China.,Department of Respiratory, Critical Care, and Sleep Medicine, Xiang'an Hospital of Xiamen University, Xiamen, China
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Maev IV, Karlovich TI, Burmistrov AI, Chekmazov IA, Andreev DN, Reshetnyak VI. Current Views of Torque Teno Virus (TTV) in Liver Diseases. RUSSIAN JOURNAL OF GASTROENTEROLOGY, HEPATOLOGY, COLOPROCTOLOGY 2020; 30:7-22. [DOI: 10.22416/1382-4376-2020-30-4-7-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Affiliation(s)
- I. V. Maev
- Moscow State University of Medicine and Dentistry
| | - T. I. Karlovich
- Central Clinical Hospital with Outpatient Care of the Russian President Administration
| | | | - I. A. Chekmazov
- Central Clinical Hospital with Outpatient Care of the Russian President Administration
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Reshetnyak VI, Maev IV, Burmistrov AI, Chekmazov IA, Karlovich TI. Torque teno virus in liver diseases: On the way towards unity of view. World J Gastroenterol 2020; 26:1691-1707. [PMID: 32351287 PMCID: PMC7183866 DOI: 10.3748/wjg.v26.i15.1691] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 03/23/2020] [Accepted: 03/26/2020] [Indexed: 02/06/2023] Open
Abstract
The review presents the data accumulated for more than 20 years of research of torque teno virus (TTV). Its molecular genetic structure, immunobiology, epidemiology, diagnostic methods, possible replication sites, and pathogenicity factors are described. TTV is a virus that is frequently detectable in patients with different viral hepatitides, in cases of hepatitis without an obvious viral agent, as well as in a healthy population. There is evidence suggesting that biochemical and histological changes occur in liver tissue and bile duct epithelium in TTV monoinfection. There are sufficient histological signs of liver damage, which confirm that the virus can undergo a replicative cycle in hepatocytes. Along with this, cytological hybridization in TTV-infected cells has shown no substantial cytopathic (cell-damaging) effects that are characteristic of pathogenic hepatotropic viruses. Studying TTV has led to the evolution of views on its role in the development of human pathology. The first ideas about the hepatotropism of the virus were gradually reformed as new data became available on the prevalence of the virus and its co-infection with other viruses, including the viruses of the known types of hepatitides. The high prevalence of TTV in the human population indicates its persistence in the body as a virome and a non-pathogenic virus. It has recently been proposed that the level of TTV DNA in the blood of patients undergoing organ transplantation should be used as an endogenous marker of the body’s immune status. The available data show the polytropism of the virus and deny the fact that TTV can be assigned exclusively to hepatitis viruses. Fortunately, the rare detection of the damaging effect of TTV on hepatic and bile duct epithelial cells may be indirect evidence of its conditionally pathogenic properties. The ubiquity of the virus and the variability of its existence in humans cannot put an end to its study.
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Affiliation(s)
- Vasiliy I Reshetnyak
- Department of Propaedeutic of Internal Diseases and Gastroenterology, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, Moscow 127473, Russia
| | - Igor V Maev
- Department of Propaedeutic of Internal Diseases and Gastroenterology, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, Moscow 127473, Russia
| | - Alexandr I Burmistrov
- Department of Propaedeutic of Internal Diseases and Gastroenterology, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, Moscow 127473, Russia
| | - Igor A Chekmazov
- Central Clinical Hospital with Polyclinic, Presidential Administration of the Russian Federation, Moscow 121359, Russia
| | - Tatiana I Karlovich
- Central Clinical Hospital with Polyclinic, Presidential Administration of the Russian Federation, Moscow 121359, Russia
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Surveillance and impact of occult hepatitis B virus, SEN virus, and torque teno virus in Egyptian hemodialysis patients with chronic hepatitis C virus infection. Int J Infect Dis 2019; 92:13-18. [PMID: 31863879 DOI: 10.1016/j.ijid.2019.12.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/12/2019] [Accepted: 12/08/2019] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVES Egypt ranks first regarding the prevalence of hepatitis C virus (HCV) infection. Many patients have concomitant diseases like kidney disorders requiring hemodialysis, a procedure carrying the hazard of transmitting other hepatitis viruses. The purpose of this study was to investigate for occult hepatitis B virus (HBV), SEN virus (SENV), and torque teno virus (TTV) among chronic HCV patients on maintenance hemodialysis to identify their impacts. METHODS A total of 325 hemodialysis patients were enrolled and divided into two groups based on HCV RNA testing results. Blood samples were collected before hemodialysis. Sera were tested for hepatitis B core antibodies (anti-HBc) and hepatitis B surface antibodies (anti-HBs) using ELISA. HBV, SENV, and TTV DNA were detected by PCR. The serum alanine aminotransferase (ALT) level was measured. RESULTS Anti-HBc and HBV DNA were detected in 73.1% and 50.8% of group 1 versus 36.4% and 22.6% of group 2. The serum ALT level was higher in group 1 than group 2. SENV was detected in 11.5% of group 1 versus 8.2% of group 2. TTV was detected in 29% of group 1 versus 27% of group 2. CONCLUSIONS There is an increased prevalence of occult HBV in our locality among chronic HCV patients undergoing hemodialysis. The existence of SENV and TTV viremia has no clinical impact.
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Rinonce HT, Yano Y, Utsumi T, Heriyanto DS, Anggorowati N, Widasari DI, Ghozali A, Utoro T, Lusida MI, Soetjipto, Prasanto H, Hayashi Y. Prevalence and genotypic distribution of GB virus C and torque teno virus among patients undergoing hemodialysis. Mol Med Rep 2017. [DOI: 10.3892/mmr.2017.6281] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Kazemi MJ, Yaghobi R, Iravani Saadi M, Geramizadeh B, Moayedi J. Association Between TT Virus Infection and Cirrhosis in Liver Transplant Patients. HEPATITIS MONTHLY 2015; 15:e28370. [PMID: 26504468 PMCID: PMC4612723 DOI: 10.5812/hepatmon.28370] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 05/23/2015] [Accepted: 08/19/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND Cirrhosis is one of the most severe liver complications, with multiple etiologies. The torque teno virus (TTV), also known as transfusion transmitted virus, which has a high incidence in the world population, is one of the possible increasing risk factors in patients with idiopathic fulminant hepatitis and cryptogenic cirrhosis. OBJECTIVES The aim of this study was to evaluate solitary and co-infection with TTV, in patients with cryptogenic and determined cause of cirrhosis. PATIENTS AND METHODS In this cross-sectional study, 200 liver transplant patients were consecutively recruited between years 2007 and 2011. Patients were classified, based on recognition of the etiology of cirrhosis to determined (n = 81) and cryptogenic (n = 119) patient groups. The existence of TTV infection was analyzed, using a semi-nested polymerase chain reaction method. The presence of hepatitis B virus (HBV) infective markers, including HBV DNA, hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), hepatitis B core antibody (HBcAb), and hepatitis B e antibody (HBeAb), was evaluated using qualitative polymerase chain reaction and enzyme linked immunosorbent assay protocols, respectively. RESULTS The TTV infection was found in 37 of 200 (18.5%) and 53 of 200 (26.5%) plasma and tissue samples of studied liver transplanted patients, respectively. The TTV genomic DNA was found in 32 (26.9%) and 28 (23.5%) of 119 liver tissue and plasma samples of transplanted patients with cryptogenic cirrhosis, respectively. The genomic DNA of TTV was also diagnosed in 21 (25.9%) and nine (11.1%) of the 81 liver tissue and plasma samples of patients with determined cirrhosis, respectively. Significant associations were found between TTV infection with HBV molecular and immunologic infective markers, in liver transplanted patients, with determined and cryptogenic cirrhosis. CONCLUSIONS The diagnosis of the high frequency of solitary TTV and co-infection with HBV, in both liver transplanted patients with cryptogenic and determined cirrhosis, emphasized on the importance of TTV infection in the development of cirrhosis, especially in the cases of cryptogenic ones, prompting for further studies the confirm this agent in the etiology of determined cirrhosis.
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Affiliation(s)
- Mohammad Javad Kazemi
- Department of Biology, Ashkezar Branch, Islamic Azad University, Ashkezar, Yazd, IR Iran
| | - Ramin Yaghobi
- Shiraz Transplant Research Center, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz, IR Iran
- Corresponding Author: Ramin Yaghobi, Shiraz Transplant Research Center, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz, IR Iran. Tel: +98-7116474331, E-mail:
| | - Mahdiyar Iravani Saadi
- Shiraz Transplant Research Center, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz, IR Iran
| | - Bita Geramizadeh
- Shiraz Transplant Research Center, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz, IR Iran
| | - Javad Moayedi
- Shiraz Transplant Research Center, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz, IR Iran
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Human anelloviruses: an update of molecular, epidemiological and clinical aspects. Arch Virol 2015; 160:893-908. [PMID: 25680568 DOI: 10.1007/s00705-015-2363-9] [Citation(s) in RCA: 177] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Accepted: 02/03/2015] [Indexed: 12/14/2022]
Abstract
Human torque teno viruses (TTVs) are new, emerging infectious agents, recently assigned to the family Anelloviridae. The first representative of the genus, torque teno virus (TTV), was discovered in 1997, followed by torque teno mini virus (TTMV) in 2000, and torque teno midi virus (TTMDV) in 2007. These viruses are characterized by an extremely high prevalence, with relatively uniform distribution worldwide and a high level of genomic heterogeneity, as well as an apparent pan-tropism at the host level. Although these viruses have a very high prevalence in the general population across the globe, neither their interaction with their hosts nor their direct involvement in the etiology of specific diseases are fully understood. Since their discovery, human anelloviruses, and especially TTV, have been suggested to be associated with various diseases, such as hepatitis, respiratory diseases, cancer, hematological and autoimmune disorders, with few arguments for their direct involvement. Recent studies have started to reveal interactions between TTVs and the host's immune system, leading to new hypotheses for potential pathological mechanisms of these viruses. In this review article, we discuss the most important aspects and current status of human TTVs in order to guide future studies.
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Mankotia DS, Irshad M. Cloning and expression of N22 region of Torque Teno virus (TTV) genome and use of peptide in developing immunoassay for TTV antibodies. Virol J 2014; 11:96. [PMID: 24884576 PMCID: PMC4032458 DOI: 10.1186/1743-422x-11-96] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 05/08/2014] [Indexed: 12/13/2022] Open
Abstract
Background Torque Teno Virus (TTV) is a DNA virus with high rate of prevalence globally. Since its discovery in 1997, several studies have questioned the role of this virus in causing disease. However, it still remains an enigma. Although methods are available for detection of TTV infection, there is still a need for simple, rapid and reliable method for screening of this virus in human population. Present investigation describes the cloning and expression of N22 region of TTV-genome and the use of expressed peptide in development of immunoassay to detect anti-TTV antibodies in serum. Since TTV genotype-1 is more common in India, the serum positive for genotype-1 was used as source of N22 for expression purpose. Methods Full length N22 region of ORF1 from TTV genotype-1 was amplified and cloned in pGEM®-T Easy vector. After cloning, the amplicon was transformed and expressed as a fusion protein containing hexa-histidine tag in pET-28a(+) vector using BL21 E. coli cells as host. Expression was conducted both in LB medium as well as ZYP-5052 auto-induction medium. The expressed peptide was purified using metal-chelate affinity chromatography and used as antigen in developing a blot immunoassay. Results Analysis of translated product by SDS-PAGE and western blotting demonstrated the presence of 25 kDa polypeptide produced after expression. Solubility studies showed the polypeptide to be associated with insoluble fraction. The use of this peptide as antigen in blot assay produced prominent spot on membrane treated with sera from TTV-infected patients. Analysis of sera from 75 patients with liver and renal diseases demonstrated a successful implication of N22 polypeptide based immunoassay in screening sera for anti-TTV antibodies. Comparison of the immunoassay developed using expressed N22 peptide with established PCR method for TTV-DNA detection showed good coherence between TTV-DNA and presence of anti-TTV antibodies in the sera analysed. Conclusions This concludes that TTV N22 region may be expressed and safely used as antigen for blot assay to detect anti-TTV antibodies in sera.
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Affiliation(s)
| | - Mohammad Irshad
- Clinical Biochemistry Division, Department of Laboratory Medicine, All India Institute of Medical Sciences, New Delhi 110029, India.
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Massaú A, Martins C, Nachtigal GC, Araújo AB, Rossetti ML, Niel C, da Silva CMD. The high prevalence of Torque teno virus DNA in blood donors and haemodialysis patients in southern Brazil. Mem Inst Oswaldo Cruz 2013; 107:684-6. [PMID: 22850961 DOI: 10.1590/s0074-02762012000500017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2011] [Accepted: 01/11/2012] [Indexed: 12/26/2022] Open
Abstract
This study investigates the frequency of Torque teno virus (TTV) infection in 150 blood donors and 77 patients requiring haemodialysis in southern Brazil. Plasma samples were screened for TTV DNA using polymerase chain reaction (PCR). The prevalences of TTV among blood donors and patients requiring haemodialysis were 73.3% and 68.8%, respectively. The presence of TTV was correlated with age in the blood donors (p = 0.024). In haemodialysis patients, no association was found between TTV infection and the demographic parameters (age, sex and education), the duration of haemodialysis or a history of blood transfusion. This study is the first to evaluate the prevalence of TTV infection in Brazilian patients requiring haemodialysis.
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Affiliation(s)
- Aline Massaú
- Programa de Pós-graduação em Diagnóstico Genético e Molecula, Universidade Luterana do Brasil, Canoas, RS, Brasil, 92425-900
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Czaja AJ. Cryptogenic chronic hepatitis and its changing guise in adults. Dig Dis Sci 2011; 56:3421-38. [PMID: 21647651 DOI: 10.1007/s10620-011-1769-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Accepted: 05/20/2011] [Indexed: 12/11/2022]
Abstract
Cryptogenic chronic hepatitis is a disease that is unexplained by conventional clinical, laboratory and histological findings, and it can progress to cirrhosis, develop hepatocellular carcinoma, and require liver transplantation. The goals of this review are to describe the changing phenotype of cryptogenic chronic hepatitis in adults, develop a diagnostic algorithm appropriate to current practice, and suggest treatment options. The frequency of cryptogenic hepatitis is estimated at 5.4%. Cryptogenic cirrhosis is diagnosed in 5-30% of patients with cirrhosis, and it is present in 3-14% of adults awaiting liver transplantation. Nonalcoholic fatty liver disease has been implicated in 21-63% of patients, and autoimmune hepatitis is a likely diagnosis in 10-54% of individuals. Viral infections, hereditary liver diseases, celiac disease, and unsuspected alcohol or drug-induced liver injury are recognized infrequently in the current cryptogenic population. Manifestations of the metabolic syndrome heighten the suspicion of nonalcoholic fatty liver disease, and the absence of hepatic steatosis does not discount this possibility. The diagnostic scoring system of the International Autoimmune Hepatitis Group can support the diagnosis of autoimmune hepatitis in some patients. Certain genetic mutations may have disease-specificity, and they suggest that some patients may have an independent and uncharacterized disease. Corticosteroid therapy is effective in patients with autoimmune features, and life-style changes and specific therapies for manifestations of the metabolic syndrome are appropriate for all obese patients. The 1- and 5-year survivals after liver transplantation have ranged from 72-85% to 58-73%, respectively.
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Affiliation(s)
- Albert J Czaja
- Division of Gastroenterology and Hepatology, Mayo Clinic College of Medicine, 200 First Street S.W., Rochester, MN 55905, USA.
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