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Tobias Heintges

Publications and source records attributed to Tobias Heintges.

14 recordsLinked to original sources
PubMed2006

[Update hepatitis D].

The relevance of chronic hepatitis delta results from its high morbidity. Prevalence of hepatitis D decreases in classic endemic areas of the Mediterranean Basin, but increases in Eastern European countries. Hepatitis D is mainly a disease of immigrants in Germany. Hepatitis D virus (HDV) is an incomplete virus, which needs the hepatitis B surface protein (HBsAg) but not hepatitis B virus (HBV) replication for its propagation. In case of HBsAg detection a screening for HDV antibodies should be performed. Simultaneous HDV/HBV infection leading to spontaneous virus clearance in the majority of cases has to be differentiated from HDV superinfection with a high rate of chronification. Chronic hepatitis D is difficult to treat. Treatment regimens for hepatitis D are interferon-based so far. Pegylated interferons, a prolongation of treatment beyond 12 months, combination therapies with ribavirin and prenylation inhibitors are possibly new therapeutic options in chronic hepatitis C.

Antiviral Agents↗
PubMed2006

Extended treatment duration for hepatitis C virus type 1: comparing 48 versus 72 weeks of peginterferon-alfa-2a plus ribavirin.

BACKGROUND & AIMS: The treatment of patients infected with hepatitis C virus (HCV) type 1 remains a challenge necessitating innovative strategies to improve treatment outcome. The extension of treatment duration beyond 48 weeks is one possible strategy to address this problem. METHODS: The efficacy and safety of 48 weeks (group A, N = 230) vs 72 weeks (group B, N = 225) of treatment with pegylated-interferon-alfa-2a (180 microg/wk) plus ribavirin (800 mg/day) were studied in treatment-naive patients with HCV type 1 infection. On-treatment and sustained virologic response (SVR) 24 weeks after stopping treatment was assessed by qualitative reverse-transcription polymerase chain reaction (sensitivity 50 IU/mL). RESULTS: Overall, no significant differences could be observed in the treatment outcome between both groups. End-of-treatment and SVR rates in groups A and B were 71% vs 63% and 53% vs 54%, respectively. Patients with undetectable HCV-RNA levels already at weeks 4 and 12 had excellent SVR rates ranging from 76% to 84% regardless of treatment group, whereas patients shown to be still HCV-RNA positive at week 12 achieved significantly higher SVR rates when treated for 72 instead of 48 weeks (29% vs 17%, P = .040). A particular benefit from extended treatment duration was seen in patients with low-level viremia (<6000 IU/mL) at week 12. The frequency and intensity of adverse events was similar between the 2 groups. CONCLUSIONS: Extended treatment duration generally is not recommended in HCV type 1 infection and should be reserved only for patients with slow virologic response defined as HCV-RNA positive at week 12 but negative at week 24.

Adult↗
PubMed2006

Treatment of chronic hepatitis delta with pegylated interferon-alpha2b.

BACKGROUND/AIMS: Chronic hepatitis D is difficult to treat. The present pilot study investigated the efficacy and tolerability of pegylated (PEG)-interferon (IFN)-alpha2b in chronic hepatitis D. PATIENTS AND METHODS: Twelve patients with chronic hepatitis D were prospectively treated with 1.5 microg/kg PEG-IFN-alpha2b for 48 weeks and followed for 24 weeks. Sustained response (SR) was defined as undetectable hepatitis delta virus (HDV) RNA by reverse transcriptase-polymerase chain reaction and normalization of alanine aminotransferase (ALT) at 6 months after treatment. Investigations included HDV RNA kinetics, determination of hepatitis B virus (HBV) and HDV genotypes and histological evaluation. RESULTS: An SR was achieved in two out of 12 of patients (17%). The negative predictive value of a less than 3 log HDV RNA decrease at month 6 was 100%. The positive predictive value of a more than 3 log HDV RNA decrease at month 6 was 67%. A marked ALT reduction at the end of treatment was observed in responders and nonresponders. Ishak histological score was comparable at baseline and significantly improved in responders compared with nonresponders at the end of follow-up (13.5 vs. 8.0; P<0.02). CONCLUSION: The present study indicates that PEG-IFN-alpha2b is a promising treatment option in chronic hepatitis D. Nonresponders could be identified by a less than 3 log decrease of HDV RNA at 6 months of treatment.

Adult↗
PubMed2005

SEN virus has an adverse effect on the survival of HIV-positive patients.

BACKGROUND: Patients infected with HIV are often coinfected with other viruses. OBJECTIVE: To investigate the effect of SEN virus (SENV) strains D and H on mortality in HIV-positive patients. METHODS: A total of 217 HIV-positive patients were analysed retrospectively after first presentation and blood sampling (January 1997 to July 1997) and the effect of coinfection with SENV-D and SENV-H on survival was examined. Analysis periods were the time from blood sampling to the end of follow-up, and the time from diagnosis of HIV infection to the end of study follow-up. SENV-H DNA was measured quantitatively. Prevalences of SENV-D and SENV-H were compared with those in 112 healthy blood donors. RESULTS: SENV prevalence was significantly higher in HIV-positive patients than in controls (56/217 and 12/112, respectively; P < 0.001). SENV positivity had no influence on survival, but a significant negative influence of SENV-H on survival was observed when SENV-H DNA was > 530 copies/ml, which was the mean SENV-H DNA level found in HIV-negative controls. This adverse effect was found for both studied time periods in a Kaplan-Meier analyses. A multivariate Cox regression analysis, including CD4 cell count, Centers for Disease Control and Prevention stage, age, sex, HIV RNA, highly active antiretroviral therapy and hepatitis C virus status, revealed that a high SENV DNA level was an independent risk factor or indicator for adverse disease outcome. CONCLUSION: SENV infection is common in HIV-positive patients. High SENV-H DNA levels were predictive for poor survival in HIV-positive patients.

Adult↗
PubMed2005

Peginterferon-alpha-2a (40KD) and ribavirin for 16 or 24 weeks in patients with genotype 2 or 3 chronic hepatitis C.

BACKGROUND & AIMS: Standard therapy of patients with chronic hepatitis C virus (HCV) infected with HCV genotype-2 or -3 is the combination of pegylated interferon-alpha and ribavirin for 24 weeks. Whether shorter treatment durations are possible for these patients without compromising sustained virologic response rates is unknown. METHODS: Patients chronically infected with HCV-2 (n = 39), HCV-2/3 (n = 1), or HCV-3 (n = 113) were treated with peginterferon-alpha-2a (180 microg/wk) plus ribavirin 800-1200 mg/day. HCV RNA was quantitatively assessed after 4 weeks. Patients with a rapid virologic response (HCV RNA below 600 IU/mL) were randomized for a total treatment duration of 16 (group A) or 24 weeks (group B). All patients with HCV RNA > or =600 IU/mL at week 4 (group C) were treated for 24 weeks. End-of-treatment and sustained virologic response were assessed by qualitative RT-PCR (sensitivity 50 IU/mL). RESULTS: Only 11 of 153 patients (7%) were allocated to group C. End-of-treatment and sustained virologic response rates were 94% and 82%, (group A), 85% and 80% (group B), and 73% and 36% (group C), respectively. In patients infected with genotype HCV-3 and high viral load (>800,000 IU/mL), a significant lower sustained virologic response rate was found than in patients infected with HCV-3 and a viral load lower or equal to 800,000 IU/mL (59% vs 85%, respectively; P = .003). CONCLUSIONS: In HCV-2 and -3 (low viral load)-infected patients who have a rapid virologic response, treatment for 16 weeks with peginterferon-alpha-2a and ribavirin is sufficient. In patients infected by HCV-3 (high viral load), longer treatment may be necessary.

Adult↗
PubMed2004

SEN virus seroprevalence in HIV positive patients: association with immunosuppression and HIV-replication.

BACKGROUND: Patients infected with HIV are often co-infected with other viruses. SEN virus (SENV) was isolated from a HIV positive patient with intravenous drug use and post-transfusion hepatitis. SENV strains D and H seem to be relevant for the development of post-transfusion hepatitis. We compared the prevalence of SENV strains D and H and the viral load of SENV H in HIV-infected patients with healthy blood donors. The results were correlated with clinical markers such as HIV stage, CD4 cell count, HIV-RNA positivity, HAART or the transmission mode in HIV infected individuals. OBJECTIVES: Blood samples of 143 HIV-positive patients were analysed and compared with a control group of 122 healthy blood donors. SENV D and -H was detected by PCR. RESULTS: SENV was detectable in 15.4% (22/143) of HIV-positive patients compared to 10.4% (12/122) in the control group (P=0.18). SENV H DNA-levels were significantly higher in HIV-positive patients (P=0.01). The prevalence in patients with CD4 cells less than 200/mm(3) was 31% (13/42), compared to 12.3% (8/65) in cases with CD4 cells between 200 and 500/mm(3), and 2.8% in cases with CD4 cells above 500/mm(3) (P=0.002 for CD4 cells <200 versus CD4 cells >200, P=0.031 for CD4 cells <500 versus CD4 cells >500). Prevalence of these strains was not significantly influenced by CDC stages. SENV was detected significantly more frequent in patients with detectable HIV-RNA (P=0.005). Patients undergoing HAART were significantly less frequent positive for SENV D or -H (P=0.029) than patients without HAART. In a multivariate analysis using a logistic regression model HIV-RNA positivity and CD4 cell count were identified as independent factors for SENV prevalence. CONCLUSION: SENV (D and H) prevalence is not significantly higher in HIV-positive patients in comparison to healthy blood donors. SENV prevalence depends on CD4 cell count and HIV-RNA.

Adult↗
PubMed2004

SEN virus does not affect treatment response in hepatitis C virus coinfected patients but SEN virus response depends on SEN virus DNA concentration.

AIM: To clarify the effect of SEN virus (SENV) infection on a combination therapy including interferon alfa (IFN-alpha) or pegylated-IFN with ribavirin in patients with chronic hepatitis and the effect of a combination therapy on SENV. METHODS: SENV DNA was determined by polymerase chain reaction in serum samples from 95 patients with chronic hepatitis C. Quantitative analysis was done for SENV H DNA. RESULTS: Twenty-one (22%) of 95 patients were positive for SENV DNA. There was no difference in clinical and biochemical parameters between patients with HCV infection alone and coinfected patients. The sustained response rate for HCV clearance after combination therapy did not differ between patients with SENV (52%) and without SENV (50%, n.s.). SENV DNA was undetectable in 76% of the initially SENV positive patients at the end of follow-up. SENV H response to combination therapy was significantly correlated with SENV DNA level (P=0.05). CONCLUSION: SENV infection had no influence on the HCV sustained response rate to the combination therapy. Response rate of SENV to the combination therapy depends on SENV DNA level.

Adult↗
PubMed2004

Psychomotor slowing in hepatitis C and HIV infection.

BACKGROUND: Both HIV and hepatitis C virus (HCV) may enter the central nervous system and cause cognitive and/or motor dysfunction. There are limited data on cognition and no data on motor performance in HIV/HCV-coinfected patients. OBJECTIVE: To provide data on cognition and motor performance in HIV/HCV infected patients. METHODS: We compared 43 HIV-seropositive but HCV-seronegative patients, 43 HIV/HCV-coinfected patients, and 44 HIV-negative but HCV-positive patients, all of whom went through neuropsychologic testing and electrophysiologic assessment of basal ganglia-mediated motor function. RESULTS: No significant differences could be found among the groups with regard to premorbid verbal and actual nonverbal intelligence, attention, and memory; the HIV dementia scale; and all somatic and most psychiatric complaints. Affective disorders were less frequent in HIV-negative but HCV-positive patients. This group also scored lower for depression. For all 3 groups, significant pathologic slowing of most rapid alternating movements (right hand) compared with those of HIV/HCV-negative controls as well as significantly prolonged contraction times (both hands) could be diagnosed. Simple reaction times were significantly prolonged only in HIV/HCV-coinfected patients. CONCLUSIONS: Although clinically asymptomatic, both HIV-positive and HCV-positive patients may show affective disturbances and significant psychomotor slowing. A potential predictive value for the further course of infection, which is well established in HIV-positive patients, remains to be investigated in HCV-positive or HIV/HCV-coinfected patients.

Adult↗
PubMed2003

Combination treatment of IFNalpha2b and ribavirin in patients with chronic hepatitis C and persistently normal ALTs.

Combination therapy of interferon-alpha2b and ribavirin was prospectively evaluated in 20 patients with chronic replicative hepatitis and persistently normal ALTs. Patients with normal ALTs on three or more occasions within 6 months received interferon-alpha2b 3 MU three times a week with ribavirin 1000-1200 mg everyday for 12 months and had a follow-up of 6 months. HCV genotype 1 was found in 16, and HCV genotype 2 or 3 in 4 patients. No patient experienced an ALT elevation during therapy. Ten of 20 patients (50%) cleared virus at the end of treatment. In an intent-to-treat analysis, a sustained virological response (SR) was achieved in 8 of 20 patients (40%). Nonresponse occurred in 5 patients. Relapse and breakthrough were seen in 2 patients each. Treatment was discontinued in 3 patients due to side effects. Interferon (IFN) ribavirin combination therapy is effective in patients with normal ALTs and appears superior to IFN monotherapy.

Administration, Oral↗
PubMed2003

Abrogation of hepatitis C virus NS3 helicase enzymatic activity by recombinant human antibodies.

The hepatitis C virus (HCV) NS3 protein possesses both protease and helicase activities and is essential for virus replication and maturation. Specific inhibition of NS3 enzymatic activity can be achieved by antibody binding. Transduction of hepatocytes with encoding cDNA leading to intracellular expression of antibody fragments is expected to terminate HCV replication in infected cells. The objective of the present study was the generation of human antibody fragments that neutralize the viral NS3 helicase activity for gene therapeutic applications and drug design. A human immunoglobulin phage-display library cloned from bone marrow aspirate of patients infected with HCV was used for affinity selection against HCV NS3 helicase. Antibody fragments with high affinity to HCV helicase were isolated. To evaluate the inhibitory potential of isolated single-chain antibody fragments, a helicase-mediated, DNA-unwinding enzymatic assay was developed in ELISA format. Recombinant protein comprising the full-length HCV NS3 helicase domain was expressed in the baculovirus expression system. Recombinant antibodies that inhibit the HCV helicase at nanomolar concentrations, with efficacies ranging from 20 % to complete abrogation of enzymatic unwinding activity, were identified. These antibody fragments may be useful for novel gene therapeutic strategies that employ intracellular immunization and may provide new insights into the design of small molecule inhibitors of essential HCV proteins.

Amino Acid Sequence↗
PubMed2002

Hepatitis C virus core protein induces cell proliferation and activates ERK, JNK, and p38 MAP kinases together with the MAP kinase phosphatase MKP-1 in a HepG2 Tet-Off cell line.

Hepatitis C virus (HCV) core protein is a multifunctional protein interacting with cellular and viral proteins and promoters. A tetracycline-regulated system was used to generate a HepG2 Tet-Off cell line allowing regulated expression of a full-length (191 aa) and an N(c)-truncated core protein (160 aa). In this system HCV core protein expression activates extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase (JNK), and p38 mitogen-activated protein (MAP) kinase, induces MAP kinase phosphatase MKP-1 expression, and increases cell proliferation. This was accompanied by an activation of c-Jun and ATF-2, but not Elk-1 and c-Fos. Furthermore, AP-1 activation was independent of c-Fos. Full-length and N(c)-truncated HCV core proteins exerted similar effects.

Cell Line↗
PubMed2002

Cloning and molecular characterization of human high affinity antibody fragments against Hepatitis C virus NS3 helicase.

Hepatitis C Virus (HCV) non-structural protein 3 (NS3) helicase is essential for viral replication. Cloning of human antibody fragments for binding and inhibiting HCV helicase intracellularly (intracellular immunization) was attempted. A phage display system was employed to isolate human sFv fragments. A large phagemid library was cloned from patients infected with HCV. Phages expressing human sFv fragments with binding activity against NS3 were highly enriched during affinity selection. Selected sFv antibody fragments showed high affinity to HCV helicase. The variable domains of the cloned antibody fragments were sequenced and their germ-line origin was determined. K(D) values describing affinity of sFv to NS3 were measured by competition-EIA. Bacterially expressed recombinant human high affinity antibodies can be used for diagnostic and therapeutic purposes. Further experiments will select antibody fragments inhibiting NS3 helicase. Employing vectors for transduction of the encoding cDNA into infected cells might be a novel gene therapy strategy for intracellular immunization against chronic HCV infection.

Amino Acid Sequence↗
PubMedDate not supplied

SEN virus infection.

The SEN virus (SEN-V) belongs to a recently discovered group of DNA viruses whose members (SEN-V-D and SEN-V-H) are associated with post-transfusion hepatitis. It is a single-stranded circular, non-enveloped DNA virus of approximately 3600 to approximately 3800 nucleotides with at least three open reading frames (ORFs). Eight different strains of SEN-V have been identified and provisionally classified as members of the Circoviridae family, a group of small, single-stranded, non-enveloped circular DNA viruses that includes the TT virus (TTV), TUS01, SANBAN, PMV and YONBAN. Prevalences in different populations show great variability with marked differences between different countries and groups. Although parenteral transmission is very likely, other routes of transmission cannot be excluded. Mother to infant transmission has been demonstrated. The effect of SEN-V on chronic liver diseases has been studied. The influence of SEN-V on the response to HCV therapy was investigated in three studies, with contradictory results. Data for other acute and chronic liver diseases are sparse. Further studies are needed to define the pathogenesis and clinical importance of SEN-V infection.

Adult↗