{"id":{"repo_id":"freiburg-diss","oai_identifier":"oai:freidok.uni-freiburg.de:1479"},"canonical_url":"https://search.dev.ndltd.org/etd/freiburg-diss/oai:freidok.uni-freiburg.de:1479","repository":{"repo_id":"freiburg-diss","name":"University of Freiburg","base_url":"https://freidok.uni-freiburg.de/oai/oai2.php"},"display":{"title":"Heterogeneity of hepatitis C-virus in genotype 1 patients treated with the combination therapy of pegylated interferon and ribavirin","abstract":"Hepatitis C is a global health problem. Hepatitis C virus is the etiological agent. After the acute phase of infection, which is asymptomatic in most patients, at least 80% of patients develop chronic hepatitis C. 20%-40% of infected people may develop cirrhosis, and 2%-4% of them may ultimately develop liver cancer. At present, HCV-related end-stage liver disease is the leading reason for liver transplantation.
Hepatitis C has been first described in 1989. Over the past 15 years treatment has been constantly improved. Today a combination therapy with pegylated interferon a (PEG-IFN) and ribavirin is recommended. The sustained virological response rate six months after stop of treatment (SVR) is about > 55% in treatment naive patients. Because the treatment with PEG-IFN plus ribavirin is 6 to 12 months with a large number of adverse events and costly, it is mandatory to find factors to predict the effect of therapy.
As a typical RNA virus, HCV has a high mutation rate, which is especially pronounced in the HVR1 of the N-amino terminal region of E2. Genotypes, subtypes and quasispecies can be distinguished. Quasispecies refer to the genetic diversity of a virus population that can be observed in a single infected individual with individual viral genomes differing 1%-5% in nucleotide sequence. Single stand conformation polymorphism (SSCP) is an accurate and reproducible method to study the complexity of HCV quasispecies.
This study investigated the degree of complexity of HCV by f-SSCP. The data suggest that f-SSCP reflects the complexity of HCV quasispecies. Complexity – identified by the number of f SSCP peaks, is an important factor for the response to treatment with PEG-IFN plus ribavirin. A low number of SSCP peaks indicate a low degree of HCV quasispecies complexity, which corresponds with a higher response rate to therapy. Low HCV quasispecies in genotype 1 patient might be an additional predictor to response to therapy. On the other hand it could be shown that treatment with PEG-IFN plus ribavirin affects the quasispecies complexity of HCV.
The data indicate that quasispecies may be an additional factor which may be important for the response of the chronic HCV infection to PEG-IFN and Ribavirin.","abstract_html":"Hepatitis C is a global health problem. Hepatitis C virus is the etiological agent. After the acute phase of infection, which is asymptomatic in most patients, at least 80% of patients develop chronic hepatitis C. 20%-40% of infected people may develop cirrhosis, and 2%-4% of them may ultimately develop liver cancer. At present, HCV-related end-stage liver disease is the leading reason for liver transplantation. <br>Hepatitis C has been first described in 1989. Over the past 15 years treatment has been constantly improved. Today a combination therapy with pegylated interferon a (PEG-IFN) and ribavirin is recommended. The sustained virological response rate six months after stop of treatment (SVR) is about > 55% in treatment naive patients. Because the treatment with PEG-IFN plus ribavirin is 6 to 12 months with a large number of adverse events and costly, it is mandatory to find factors to predict the effect of therapy. <br>As a typical RNA virus, HCV has a high mutation rate, which is especially pronounced in the HVR1 of the N-amino terminal region of E2. Genotypes, subtypes and quasispecies can be distinguished. Quasispecies refer to the genetic diversity of a virus population that can be observed in a single infected individual with individual viral genomes differing 1%-5% in nucleotide sequence. Single stand conformation polymorphism (SSCP) is an accurate and reproducible method to study the complexity of HCV quasispecies. <br>This study investigated the degree of complexity of HCV by f-SSCP. The data suggest that f-SSCP reflects the complexity of HCV quasispecies. Complexity – identified by the number of f SSCP peaks, is an important factor for the response to treatment with PEG-IFN plus ribavirin. A low number of SSCP peaks indicate a low degree of HCV quasispecies complexity, which corresponds with a higher response rate to therapy. Low HCV quasispecies in genotype 1 patient might be an additional predictor to response to therapy. On the other hand it could be shown that treatment with PEG-IFN plus ribavirin affects the quasispecies complexity of HCV. <br>The data indicate that quasispecies may be an additional factor which may be important for the response of the chronic HCV infection to PEG-IFN and Ribavirin.","abstract_has_math":false,"creators":["Cao, Hua"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Rasenack, Jens"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":null,"date_issued":"","date_published":null,"updated_at":"2026-07-24T02:22:16Z","subjects":["Genotyp 1, pegyliertem Interferon","Ribavirin","genotype 1","pegylated interferon"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://freidok.uni-freiburg.de/data/1479","outbound_label":"Repository record","outbound_source":"source_url"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Rasenack, Jens"]},{"key":"dc:creator","label":"Author","values":["Cao, Hua"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:type","label":"Dc Type","values":["DoctoralThesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Genotyp 1, pegyliertem Interferon","Ribavirin","genotype 1","pegylated interferon"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Hepatitis C is a global health problem. Hepatitis C virus is the etiological agent. After the acute phase of infection, which is asymptomatic in most patients, at least 80% of patients develop chronic hepatitis C. 20%-40% of infected people may develop cirrhosis, and 2%-4% of them may ultimately develop liver cancer. At present, HCV-related end-stage liver disease is the leading reason for liver transplantation.
Hepatitis C has been first described in 1989. Over the past 15 years treatment has been constantly improved. Today a combination therapy with pegylated interferon a (PEG-IFN) and ribavirin is recommended. The sustained virological response rate six months after stop of treatment (SVR) is about > 55% in treatment naive patients. Because the treatment with PEG-IFN plus ribavirin is 6 to 12 months with a large number of adverse events and costly, it is mandatory to find factors to predict the effect of therapy.
As a typical RNA virus, HCV has a high mutation rate, which is especially pronounced in the HVR1 of the N-amino terminal region of E2. Genotypes, subtypes and quasispecies can be distinguished. Quasispecies refer to the genetic diversity of a virus population that can be observed in a single infected individual with individual viral genomes differing 1%-5% in nucleotide sequence. Single stand conformation polymorphism (SSCP) is an accurate and reproducible method to study the complexity of HCV quasispecies.
This study investigated the degree of complexity of HCV by f-SSCP. The data suggest that f-SSCP reflects the complexity of HCV quasispecies. Complexity – identified by the number of f SSCP peaks, is an important factor for the response to treatment with PEG-IFN plus ribavirin. A low number of SSCP peaks indicate a low degree of HCV quasispecies complexity, which corresponds with a higher response rate to therapy. Low HCV quasispecies in genotype 1 patient might be an additional predictor to response to therapy. On the other hand it could be shown that treatment with PEG-IFN plus ribavirin affects the quasispecies complexity of HCV.
The data indicate that quasispecies may be an additional factor which may be important for the response of the chronic HCV infection to PEG-IFN and Ribavirin.","Die Hepatitis C stellt ein globales gesundheitliches Problem dar. Das Hepatitis C Virus ist das ätiologische Agens. Nach der akuter Infektionsphase, in der die meisten Patienten keine Symptome haben, kommt es bei mindestens 80% der Patienten zu einer chronischen Hepatitis C. 20%-40% der Patienten bekommen eine Zirrhose, und 2%-4% der Patienten ein Leberzellkarzinom. Die Leberzirrhose, auf dem Boden einer chronischen Hepatitis C, stellt heute die Hauptindikation zur Lebertransplantation dar.
Die Hepatitis C wird erstmal in 1989 geschrieben. In den vergangenen 15 Jahren wurde die Therapie kontinuierlich verbessert. Zurzeit besteht sie aus einer Kombination von pegyliertem Interferon a (PEG-IFN) und Ribavirin. Die virologische Langzeiterfolgsrate 24 Wochen nach Therapieende (SVR) beträgt bei zuvor unbehandelten Patienten t > 55%. Da die Therapiedauer in Abhängigkeit 24 oder 48 Wochen beträgt, zahlreiche Nebenwirkungen hat und kostenintensiv ist, ist es notwendig nach zusätzlichen Faktoren zu suchen um die Erfolgsaussichten besser abschätzen zu können.
Das HCV ist ein typisches RNA-Virus mit einer hohen Mutationsrate, speziell im Bereich der N-amino terminalen Region von E2 (HVR1). Es können Genotypen, Subtypen und so genannte Quasispezies unterschieden werden. Bei letzteren beträgt der Sequenzunterschied 1-5%. Verschiedene Quasispezies treten bei und demselben Patienten auf und sind ein Ausdruck für eine Heterogenität der Viruspopulation. Diese kann mit der „Single Strand Conformation Polymorphism“-Methode untersucht werden. Diese Methode ist bei identischen Untersuchungsbedingungen zuverlässig.
In dieser Studie wurde die Komplexität der HCV-Population bei Patienten, die erfolgreich oder –erfolglos mit einer Kombinationstherapie mit PEG-IFN und Ribavirin behandelt worden waren mit der SSCP untersucht. Die Ergebnisse zeigen, dass das Ausmaß der Virusheterogenität ein wichtiger Faktor für das Ansprechen auf die Therapie ist. Eine geringe Zahl von Quasispezies bei einem Patienten führt häufiger zur SVR als eine ausgeprägte Heterogenität. Außerdem kann gezeigt werden, dass die Behandlung die Virusheterogenität beeinflusst.
Die Ergebnisse zeigen, dass die Virusheterogenität ein zusätzlicher Faktor für den Therapieerfolg bei der chronischen Hepatitis darstellt."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Heterogeneity of hepatitis C-virus in genotype 1 patients treated with the combination therapy of pegylated interferon and ribavirin","Heterogenitaet des Hepatitis C-Virus, Genotyp 1 bei Patienten unter Kombinationstherapie mit pegyliertem Interferon und Ribavirin"]}]}],"canonical_facts":{"dc:contributor":["Rasenack, Jens"],"dc:creator":["Cao, Hua"],"dc:description.abstract":["Hepatitis C is a global health problem. Hepatitis C virus is the etiological agent. After the acute phase of infection, which is asymptomatic in most patients, at least 80% of patients develop chronic hepatitis C. 20%-40% of infected people may develop cirrhosis, and 2%-4% of them may ultimately develop liver cancer. At present, HCV-related end-stage liver disease is the leading reason for liver transplantation.
Hepatitis C has been first described in 1989. Over the past 15 years treatment has been constantly improved. Today a combination therapy with pegylated interferon a (PEG-IFN) and ribavirin is recommended. The sustained virological response rate six months after stop of treatment (SVR) is about > 55% in treatment naive patients. Because the treatment with PEG-IFN plus ribavirin is 6 to 12 months with a large number of adverse events and costly, it is mandatory to find factors to predict the effect of therapy.
As a typical RNA virus, HCV has a high mutation rate, which is especially pronounced in the HVR1 of the N-amino terminal region of E2. Genotypes, subtypes and quasispecies can be distinguished. Quasispecies refer to the genetic diversity of a virus population that can be observed in a single infected individual with individual viral genomes differing 1%-5% in nucleotide sequence. Single stand conformation polymorphism (SSCP) is an accurate and reproducible method to study the complexity of HCV quasispecies.
This study investigated the degree of complexity of HCV by f-SSCP. The data suggest that f-SSCP reflects the complexity of HCV quasispecies. Complexity – identified by the number of f SSCP peaks, is an important factor for the response to treatment with PEG-IFN plus ribavirin. A low number of SSCP peaks indicate a low degree of HCV quasispecies complexity, which corresponds with a higher response rate to therapy. Low HCV quasispecies in genotype 1 patient might be an additional predictor to response to therapy. On the other hand it could be shown that treatment with PEG-IFN plus ribavirin affects the quasispecies complexity of HCV.
The data indicate that quasispecies may be an additional factor which may be important for the response of the chronic HCV infection to PEG-IFN and Ribavirin.","Die Hepatitis C stellt ein globales gesundheitliches Problem dar. Das Hepatitis C Virus ist das ätiologische Agens. Nach der akuter Infektionsphase, in der die meisten Patienten keine Symptome haben, kommt es bei mindestens 80% der Patienten zu einer chronischen Hepatitis C. 20%-40% der Patienten bekommen eine Zirrhose, und 2%-4% der Patienten ein Leberzellkarzinom. Die Leberzirrhose, auf dem Boden einer chronischen Hepatitis C, stellt heute die Hauptindikation zur Lebertransplantation dar.
Die Hepatitis C wird erstmal in 1989 geschrieben. In den vergangenen 15 Jahren wurde die Therapie kontinuierlich verbessert. Zurzeit besteht sie aus einer Kombination von pegyliertem Interferon a (PEG-IFN) und Ribavirin. Die virologische Langzeiterfolgsrate 24 Wochen nach Therapieende (SVR) beträgt bei zuvor unbehandelten Patienten t > 55%. Da die Therapiedauer in Abhängigkeit 24 oder 48 Wochen beträgt, zahlreiche Nebenwirkungen hat und kostenintensiv ist, ist es notwendig nach zusätzlichen Faktoren zu suchen um die Erfolgsaussichten besser abschätzen zu können.
Das HCV ist ein typisches RNA-Virus mit einer hohen Mutationsrate, speziell im Bereich der N-amino terminalen Region von E2 (HVR1). Es können Genotypen, Subtypen und so genannte Quasispezies unterschieden werden. Bei letzteren beträgt der Sequenzunterschied 1-5%. Verschiedene Quasispezies treten bei und demselben Patienten auf und sind ein Ausdruck für eine Heterogenität der Viruspopulation. Diese kann mit der „Single Strand Conformation Polymorphism“-Methode untersucht werden. Diese Methode ist bei identischen Untersuchungsbedingungen zuverlässig.
In dieser Studie wurde die Komplexität der HCV-Population bei Patienten, die erfolgreich oder –erfolglos mit einer Kombinationstherapie mit PEG-IFN und Ribavirin behandelt worden waren mit der SSCP untersucht. Die Ergebnisse zeigen, dass das Ausmaß der Virusheterogenität ein wichtiger Faktor für das Ansprechen auf die Therapie ist. Eine geringe Zahl von Quasispezies bei einem Patienten führt häufiger zur SVR als eine ausgeprägte Heterogenität. Außerdem kann gezeigt werden, dass die Behandlung die Virusheterogenität beeinflusst.
Die Ergebnisse zeigen, dass die Virusheterogenität ein zusätzlicher Faktor für den Therapieerfolg bei der chronischen Hepatitis darstellt."],"dc:format.medium":["application/pdf"],"dc:subject":["Genotyp 1, pegyliertem Interferon","Ribavirin","genotype 1","pegylated interferon"],"dc:title":["Heterogeneity of hepatitis C-virus in genotype 1 patients treated with the combination therapy of pegylated interferon and ribavirin","Heterogenitaet des Hepatitis C-Virus, Genotyp 1 bei Patienten unter Kombinationstherapie mit pegyliertem Interferon und Ribavirin"],"dc:type":["DoctoralThesis"]},"updated_at":"2026-07-24T02:22:16Z"}