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O Weiland

Publications and source records attributed to O Weiland.

At least 19 recordsLinked to original sources
PubMed2006

Liver transplantation for HCV cirrhosis at Karolinska University Hospital Huddinge, Stockholm.

Hepatitis C virus (HCV)-induced cirrhosis is the major indication for liver transplantation globally, and an increasing indication for liver transplantation in Sweden. We have retrospectively examined the 120 patients transplanted for HCV cirrhosis from 1987 through 2005, including 11 who received more than one graft. The 1-, 3-, and 5-year postoperative survivals for all patients transplanted for HCV with or without hepatocellular cancer (HCC) were 77%, 66%, and 53%, respectively. HCV patients without HCC had a 1-, 3-, and 5-year survivals of 78%, 73%, and 61%, compared with 84%, 79% and 74%, respectively, for patients transplanted with chronic liver diseases without cancer or HCV. The number of patients with HCV cirrhosis transplanted in our center is increasing. Compared with patients transplanted for other chronic liver diseases, we experienced inferior results among patients with HCV cirrhosis.

Adolescent↗
PubMed2005

Relation between viral fitness and immune escape within the hepatitis C virus protease.

BACKGROUND: The hepatitis C virus (HCV) mutates within human leucocyte antigen (HLA) class I restricted immunodominant epitopes of the non-structural (NS) 3/4A protease to escape cytotoxic T lymphocyte (CTL) recognition and promote viral persistence. However, variability is not unlimited, and sometimes almost absent, and factors that restrict viral variability have not been defined experimentally. AIMS: We wished to explore whether the variability of the immunodominant CTL epitope at residues 1073-1081 of the NS3 protease was limited by viral fitness. PATIENTS: Venous blood was obtained from six patients (four HLA-A2+) with chronic HCV infection and from one HLA-A2+ patient with acute HCV infection. METHODS: NS3/4A genes were amplified from serum, cloned in a eukaryotic expression plasmid, sequenced, and expressed. CTL recognition of naturally occurring and artificially introduced escape mutations in HLA-A2-restricted NS3 epitopes were determined using CTLs from human blood and genetically immunised HLA-A2-transgenic mice. HCV replicons were used to test the effect of escape mutations on HCV protease activity and RNA replication. RESULTS: Sequence analysis of NS3/4A confirmed low genetic variability. The major viral species had functional proteases with 1073-1081 epitopes that were generally recognised by cross reactive human and murine HLA-A2 restricted CTLs. Introduction of mutations at five positions of the 1073-1081 epitope prevented CTL recognition but three of these reduced protease activity and RNA replication. CONCLUSIONS: Viral fitness can indeed limit the variability of HCV within immunological epitopes. This helps to explain why certain immunological escape variants never appear as a major viral species in infected humans.

Acute Disease↗
PubMed2005

Hepatitis C virus RNA kinetics during the initial 12 weeks treatment with pegylated interferon-alpha 2a and ribavirin according to virological response.

SUMMARY: To optimize treatment of chronic hepatitis C early identification of patients who will not achieve a sustained virological response (SVR) is desirable. We investigated hepatitis C virus (HCV) RNA kinetics at day 1 (in 15 patients; genotypes 1 and non-1, 9 and 6 respectively) at weeks 1, 4 and 12 (in 53 patients; genotypes 1 and non-1, 19 and 34, respectively) during treatment with pegylated interferon alpha-2a and ribavirin. Patients with SVR had a significantly more pronounced mean log10 decline from baseline in HCV RNA levels at weeks 1 and 4 compared with patients who failed to achieve SVR (1.99 vs 0.85 at week 1, P = 0.0003 and 2.89 vs 1.72 at week 4, P = 0.0159), whereas no difference was noted after day 1. For patients with a 2-log10 decrease in HCV RNA levels at day 7, the positive predictive value (PPV) for a SVR was 92%, whereas week 12 was the best time point for predicting a later nonresponse [negative predictive value (NPV) 92%] in patients failing to achieve a 2-log10 drop. For patients with genotype non-1 and a 2-log10 decrease in HCV RNA levels the PPV for a SVR was 89% week 1, and 79% weeks 4 and 12. The corresponding NPV for patients with genotype non-1 were 43, 40 and 100% respectively. During treatment with pegylated interferon alpha-2a plus ribavirin the HCV RNA decline at week 1 was an accurate predictor of SVR in patients who had achieved a 2-log10 drop in HCV RNA levels, whereas the lack of such decline week 12 was an accurate marker of a nonresponse.

Adult↗
PubMed2004

Codon optimization and mRNA amplification effectively enhances the immunogenicity of the hepatitis C virus nonstructural 3/4A gene.

We have recently shown that the NS3-based genetic immunogens should contain also hepatitis C virus (HCV) nonstructural (NS) 4A to utilize fully the immunogenicity of NS3. The next step was to try to enhance immunogenicity by modifying translation or mRNA synthesis. To enhance translation efficiency, a synthetic NS3/4A-based DNA (coNS3/4A-DNA) vaccine was generated in which the codon usage was optimized (co) for human cells. In a second approach, expression of the wild-type (wt) NS3/4A gene was enhanced by mRNA amplification using the Semliki forest virus (SFV) replicon (wtNS3/4A-SFV). Transient tranfections of human HepG2 cells showed that the coNS3/4A gene gave 11-fold higher levels of NS3 as compared to the wtNS3/4A gene when using the CMV promoter. We have previously shown that the presence of NS4A enhances the expression by SFV. Both codon optimization and mRNA amplification resulted in an improved immunogenicity as evidenced by higher levels of NS3-specific antibodies. This improved immunogenicity also resulted in a more rapid priming of cytotoxic T lymphocytes (CTLs). Since HCV is a noncytolytic virus, the functionality of the primed CTL responses was evaluated by an in vivo challenge with NS3/4A-expressing syngeneic tumor cells. The priming of a tumor protective immunity required an endogenous production of the immunogen and CD8+ CTLs, but was independent of B and CD4+ T cells. This model confirmed the more rapid in vivo activation of an NS3/4A-specific tumor-inhibiting immunity by codon optimization and mRNA amplification. Finally, therapeutic vaccination with the coNS3/4A gene using gene gun 6-12 days after injection of tumors significantly reduced the tumor growth in vivo. Codon optimization and mRNA amplification effectively enhances the overall immunogenicity of NS3/4A. Thus, either, or both, of these approaches should be utilized in an NS3/4A-based HCV genetic vaccine.

Animals↗
PubMed2004

Histological findings, genotype distribution and percentage of patients fulfilling the treatment criteria among patients with chronic hepatitis C virus infection in a single Swedish centre.

BACKGROUND: Genotype distribution of chronic hepatitis C in Sweden has shown a predominance of genotype non-1. With recent improvements in therapy, genotypes 2 and 3 infections can, according to consensus, be treated without histological assessment. The aim of this study was to evaluate the genotype distribution, histological stage and grade, and the percentage of patients fulfilling the histological treatment criteria. METHOD: A total of 323 patients with chronic hepatitis C were tested for genotype, histological findings and the percentage fulfilling the histological treatment criteria as stated by Swedish consensus; i.e. having fibrosis stage II or more, or fibrosis stage I with inflammation grade II or more. RESULTS: The patients had a mean age of 45 years (range 16-71 years) and 62% were males. Genotypes were determined in 79% of patients and genotype 2b or 3a was found to predominate, comprising 56%. Former intravenous drug use was found to be the predominant mode of acquisition, noted in 60%. The mean disease duration was 21 years (range 3-40) after which time 14% of patients had developed cirrhosis (stage IV). In the total material, 77% fulfilled the histological treatment criteria, 76% and 86%, respectively, among genotype I and genotype non-1 (2b and 3a) patients. CONCLUSIONS: Genotype non-1 (2b or 3a) predominated among Swedish patients, 14% of whom developed cirrhosis after a mean follow-up time of 21 years. Furthermore, an absolute majority fulfilled the histological criteria used to judge patients' eligibility for antiviral therapy, supporting the recent Swedish consensus decision to treat genotypes 2 and 3 infected patients without a previous biopsy.

Adolescent↗
PubMed2004

Long term clinical outcome of chronic hepatitis C patients with sustained virological response to interferon monotherapy.

BACKGROUND: The key end point for treatment efficacy in chronic hepatitis C is absence of detectable virus at six months after treatment. However, the incidence of clinical events during long term follow up of patients with sustained virological response is still poorly documented and may differ between the Eastern and Western world. AIMS: To assess clinical end points during long term follow up of European patients with a sustained virological response to interferon monotherapy. METHODS: Meta-analysis of individual patient data from eight European protocolled follow up studies of interferon treatment for chronic hepatitis C. RESULTS: A total of 286 sustained virological responders and 50 biochemical responders (detectable virus but normal alanine aminotransferase levels) were followed up for 59 months. Fifteen sustained virological responders (5.2%) had cirrhosis before treatment and 112 (39%) had genotype 1. The late virological relapse rate after five years of follow up was 4.7% (95% confidence interval (CI) 2.0-7.4) among sustained virological responders; all late relapses occurred within four years after treatment. Among sustained virological responders, the rate of decompensation after five years of follow up was 1.0% (95% CI 0.0-2.3) and none developed hepatocellular carcinoma (HCC). Survival was comparable with the general population, matched for age and sex, the standard mortality ratio being 1.4 (95% CI 0.3-2.5). Clinical outcome of patients with cirrhosis was similar to other sustained virological responders. For biochemical responders, the rates of development of decompensation and HCC during long term follow up were 9.1% (95% CI 0.5-17.7) and 7.1% (95% CI 0-15.0), respectively. CONCLUSIONS: Five year survival of European sustained virological responders was similar to the overall population, matched for age and sex. No HCCs were detected during long term follow up.

Adolescent↗
PubMed2002

Viral kinetics and treatment response in patients with hepatitis C during induction and standard interferon therapy in combination with ribavirin.

BACKGROUND: The early decline of hepatitis C virus (HCV) RNA levels during therapy may predict the outcome and can be utilized to improve treatment regimens. We studied the HCV RNA levels during induction and standard interferon (IFN) and ribavirin treatment. METHODS: Patients received IFN 3 MU daily for 14 days followed by 3 MU three times a week (induction group; n = 10), or IFN 3 MU three times a week from start (standard group; n = 21), in combination with ribavirin 1000-1200 mg/day. HCV RNA was quantified day 0, 1, 2, 3, 7, 14, 28, 56 and 84 during treatment, and tested qualitatively at the end of treatment and at follow-up. RESULTS: The initial viral load decline was more pronounced in the induction group, and in patients infected with genotype non-1. The sustained response rate was not significantly different between the study groups. At day 1, the mean viral load decline from baseline was significantly greater in patients who became sustained responders than in those who became non-responders; 1.4 log (96%) versus 0.3 log (55%) (P < 0.05). All sustained responders had a viral load decline of at least 0.7 log (79%) after the first IFN dose. CONCLUSIONS: Our short-term induction treatment did not improve the long-term treatment outcome significantly, although a trend was seen. An absent or low initial viral load decline can be used to predict non-response in the individual patient.

Adult↗
PubMed2001

[Give all children vaccine against hepatitis B!].

The number of individuals with chronic hepatitis B in Sweden has increased, mainly due to new immigrant groups. A safe and effective hepatitis B vaccine exists which allows a flexible dosing schedule. Most countries in the world adheres to the WHO recommendations to include this vaccine in the childhood vaccination regimen. This has led to a substantial drop in morbidity and mortality from hepatitis B virus infections in high endemic regions such as Taiwan. Sweden should consider changing its vaccination policy, including the vaccination of high risk groups only, and consider vaccination of all infants.

Adult↗
PubMed2001

GB virus C/hepatitis G virus.

GB virus C (GBV-C), or hepatitis G virus (HGV), is a recently discovered enveloped RNA virus belonging to the Flaviviridae family. GBV-C/HGV is transmitted by contaminated blood and/or blood products, intravenous drug use, from mother to child, sexually, and possibly through close social contacts. Several reports indicate a high prevalence of GBV-C/HGV viremia (1-4%) within healthy populations in Europe and North America, and an even higher prevalence (10-33%) among residents in South America and Africa. GBV-C/HGV has been suggested to be a causative agent for non-A-non-E hepatitis. However, several contradictory observations suggest that its ability to cause hepatitis is questionable. Taken together most data suggest that GBV-C/HGV is not a major cause of liver disease despite recent data indicating that it may infect and replicate in hepatocytes.

Acute Disease↗
PubMed2001

Hepatitis C virus kinetics during induction and standard 3 times a week interferon-alpha therapy.

We studied HCV kinetics during the first 84 d of interferon-alpha (IFN) treatment. IFN was administered either at a dose of 3 million units daily for the first 14 d and thereafter 3 times per week (t.i.w.) (induction treatment), or at a dose of 3 million units t.i.w. throughout (standard treatment). No patient had received HCV treatment previously, and all had a pretreatment viral load of < 1.2 x 10(6) IU/ml at screening. Ten patients were given induction treatment and 21 received the standard t.i.w. regimen. Twenty patients were infected with genotype 1. At Day 2, the median HCV RNA level in the induction group was significantly lower compared to that of the standard treatment group. This significant difference persisted during the study period for patients infected with genotype 1, but was not maintained from Day 14 onwards for patients with genotype non-1. At Day 84, 80% (8/10) of patients in the induction group, compared to 16% (3/19) in the standard treatment group, had undetectable (< 600 IU/ml) HCV RNA levels (p < 0.05). We conclude that induction treatment resulted in a significantly greater decline in HCV RNA levels than standard treatment.

Adult↗
PubMed2000

The GB virus C/hepatitis G virus replicates in hepatocytes without causing liver disease in healthy blood donors.

Thirty-seven persons were identified with GB virus C (GBV-C) single infection by polymerase chain reaction screening of 1254 healthy blood donors. Of 33 donors who returned for clinical examination, 17 underwent liver biopsy. Clinical, biochemical, and histologic evaluation did not reveal any signs of liver disease. Liver biopsies of 15 donors were analyzed by in situ hybridization with GBV-C RNA probes and immunologic staining for the GBV-C envelope 2 protein. GBV-C replication was identified in the cytoplasm of hepatocytes of 10 (67%) donor livers but in none of 7 liver biopsies of chronic hepatitis B virus carriers negative for serum GBV-C RNA. Thus, there was no evidence of liver disease in GBV-C-infected healthy blood donors despite viral replication in hepatocytes.

Adult↗
PubMed2000

Humoral and cellular immune responses to the GB virus C/hepatitis G virus envelope 2 protein.

Immune responses to two recombinant envelope 2 (E2) proteins, representing genotypes 1 and 2 of the GB virus C, or the hepatitis G virus (GBV-C/HGV), were studied in mice and in 48 individuals with, or without, chronic, or past GBV-C/HGV infection. Immunised mice developed E2-specific antibodies (mean titres, 1:1,167 to 1:9,360), recognising linear antigenic regions and proliferative and IL-2, IL-6 and gammaIFN cytokine responses regardless of the viral genotype. Individuals with past GBV-C infection had E2 antibody titres from 1:1,500 to 1:7,500 that did not recognise the E. coli derived E2 protein or linear antigenic regions. Proliferative E2-specific responses were detected in peripheral blood mononuclear cells from 6/22 (27%) persons with, and in none without GBV-C markers (P<0.05). Thus, E2-specific immune responses are mainly crossreactive between different variants of GBV-C/HGV, although proliferative responses appear to be rare.

Amino Acid Sequence↗
PubMed1999

Limited humoral immunity in hepatitis C virus infection.

BACKGROUND & AIMS: The extremely high rate of chronicity to hepatitis C virus (HVC) infection suggests an inefficient immune response. The humoral immune response to HCV was evaluated in 60 patients with chronic HCV infection and in 12 patients acutely infected with HCV. METHODS: A number of recombinant HCV antigens including the core, envelope 2 (E2), nonstructural (NS) 3, NS4, and NS5 proteins, and NS4a and E2-HVR-1 peptides were used in enzyme-linked immunoassays. RESULTS: Immunoglobulin (Ig) G antibody responses to these viral antigens, except for the HCV core, were highly restricted to the IgG1 isotype. The prevalence of antibodies of the IgG1 isotype specific for the HCV core, E2, E2-HVR1, NS3 (helicase domain), NS4, and NS5 antigens was 97%, 98%, 28%, 88%, 33%, and 68%, respectively. Antibodies of the IgG3 isotype specific for E2, E2-HVR-1, NS3, NS4, and NS5 were detected in a minority of serum samples. The IgG2 and IgG4 isotypes were rarely if ever detected. Furthermore, antibody responses to HCV viral antigens were of relatively low titer and, with the exception of anti-HCV core, were delayed in appearance until the chronic phase of infection. CONCLUSIONS: The IgG1 restriction, low titer, and delayed appearance of antibody responses elicited during HCV infection suggest that the immunogenicity of HCV proteins is limited in the context of natural infection. Inasmuch as recombinant HCV viral antigens perform as relatively normal immunogens in small animals, we suggest that the defective humoral immune responses during HCV infection may be attributable to an "immune avoidance" strategy.

Acute Disease↗
PubMed1999

Long-term follow-up of chronic hepatitis C patients with sustained virological response to alpha-interferon.

BACKGROUND/AIMS: This study aimed to determine the long-term outcome of hepatitis C virus (HCV)-infected patients who respond to interferon treatment with clearance of serum HCV RNA. METHODS: We performed a long-term biochemical, virological, and histological follow-up of all sustained virological responders, defined as those who became HCV RNA negative at follow-up 6 months after the end of treatment, from 3 controlled interferon trials performed in Sweden between 1988 and 1994. RESULTS: At biochemical and virological long-term follow-up performed in 26 sustained virological responders 3.5-8.8 years (mean +/- SD, 5.4+/-1.6 years) after the end of IFN therapy, 22 patients (85%) had normal serum ALT levels, and 24 patients (92%) were HCV RNA negative in serum. Liver biopsies performed in 23 patients 2.1-8.7 years (mean +/- SD, 5.0+/-1.8 years) after end of treatment showed no or minimal inflammation, whereas mild and probably irreversible fibrosis was seen in a few patients. CONCLUSION: In this well-defined material of sustained responders to IFN therapy, the long-term prognosis was excellent. Nearly all had a durable response, not only biochemically and virologically, but more importantly also histologically with normalisation or near normalisation of previous histological lesions.

Adult↗