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Dive into the research topics where R. Bart Takkenberg is active.

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Featured researches published by R. Bart Takkenberg.


The Journal of Infectious Diseases | 2016

Hepatitis B Virus Pregenomic RNA Is Present in Virions in Plasma and Is Associated With a Response to Pegylated Interferon Alfa-2a and Nucleos(t)ide Analogues

Louis Jansen; Neeltje A. Kootstra; Karel A. van Dort; R. Bart Takkenberg; Hendrik W. Reesink; Hans L. Zaaijer

BACKGROUND Treatment of patients with chronic hepatitis B (CHB) with nucleos(t)ide analogues (NAs) suppresses hepatitis B virus (HBV) DNA production but does not affect the synthesis of the RNA pregenome or HBV messenger RNA. Whether HBV RNA-containing particles continue to be secreted into the bloodstream remains controversial. METHODS We developed a sensitive polymerase chain reaction (PCR) assay to quantify the HBV RNA load in a supernatant of NA-treated HepG2-2.2.15 cells and in plasma specimens from 20 patients with CHB who were receiving NA therapy and 86 patients treated with pegylated interferon alfa (Peg-IFN) and adefovir. RESULTS Treatment of HepG2-2.2.15 cells with NAs for 9 days reduced HBV DNA levels (by 1.98 log10 copies/mL), whereas HBV RNA levels increased (by 0.47 log10 copies/mL; P < .05). During long-term NA treatment of patients with CHB, HBV RNA levels remained higher than HBV DNA levels. Peg-IFN-based treatment induced a stronger decrease in the HBV RNA load than NA monotherapy, and this decline was more pronounced in responders than in nonresponders. In HBV e antigen-negative patients, a lower baseline plasma HBV RNA level was independently associated with response to Peg-IFN and adefovir (odds ratio, 0.44; P = .019). Immunoprecipitation with HBV core antigen-specific antibodies after removal of the HBV surface antigen envelope demonstrated the association of plasma HBV RNA with virions. CONCLUSIONS HBV RNA is present in virions in plasma specimens from patients with CHB. HBV RNA levels vary significantly from those of established viral markers during antiviral treatment, which highlights its potential as an independent marker in the evaluation of patients with CHB.


The Journal of Infectious Diseases | 2015

Natural Killer Cell Characteristics in Patients With Chronic Hepatitis B Virus (HBV) Infection Are Associated With HBV Surface Antigen Clearance After Combination Treatment With Pegylated Interferon Alfa-2a and Adefovir

F. Stelma; Annikki de Niet; Marjan J. Tempelmans Plat-Sinnige; Louis Jansen; R. Bart Takkenberg; Hendrik W. Reesink; Neeltje A. Kootstra; Ester M. M. van Leeuwen

BACKGROUND The role of natural killer (NK) cells in the process of hepatitis B virus (HBV) surface antigen (HBsAg) clearance and whether their phenotype is related to treatment outcome in patients with chronic hepatitis B are currently unknown. METHODS Patients with chronic hepatitis B (HBV DNA load, >17 000 IU/mL) were treated with pegylated interferon alfa-2a and adefovir for 48 weeks. NK cell phenotype and function were analyzed in 7 responders (defined as individuals with HBsAg clearance by week 72; 3 HBV e antigen [HBeAg]-positive and 4 HBeAg-negative), 7 matched nonresponders, and 7 healthy controls. Subsequently, 34 baseline samples from HBeAg-positive patients with chronic hepatitis B were analyzed. RESULTS During treatment, the percentage and absolute number of CD56(bright) NK cells increased significantly, whereas the percentage and absolute number of CD56(dim) NK cells decreased. At baseline, responders had a significantly lower expression of chemokine receptor CX3CR1 on CD56(bright) NK cells and inhibitory receptor NKG2A on CD56(dim) NK cells, compared with nonresponders. In addition, responders had higher CD56(bright) TRAIL expression and interferon γ production at end of treatment. These baseline differences were not found in HBeAg-positive patients who had HBeAg seroconversion without HBsAg clearance. CONCLUSIONS Combination therapy significantly influences NK cell phenotype and function. Differences between patients with chronic hepatitis B with HBsAg clearance and nonresponders suggest that NK cells play a role in the clearance of HBsAg during interferon-based combination therapy.


Journal of Hepatology | 2016

Restoration of T cell function in chronic hepatitis B patients upon treatment with interferon based combination therapy

Annikki de Niet; F. Stelma; Louis Jansen; M.J. Sinnige; Ester B. M. Remmerswaal; R. Bart Takkenberg; Neeltje A. Kootstra; Hendrik W. Reesink; René A. W. van Lier; Ester M. M. van Leeuwen

BACKGROUND & AIMS Chronic hepatitis B virus (HBV) infection is characterized by functional impairment of HBV-specific T cells. Understanding the mechanisms behind T cell dysfunction and restoration is important for the development of optimal treatment strategies. METHODS In this study we have first analysed the phenotype and function of HBV-specific T cells in patients with low viral load (HBV DNA <20,000IU/ml) and spontaneous control over the virus. Subsequently, we assessed HBV-specific T cells in patients with high viral load (HBV DNA >17,182IU/ml) treated with peginterferon/adefovir combination therapy who had various treatment outcomes. RESULTS HBV-specific T cells could be detected directly ex vivo in 7/22 patients with low viral load. These showed an early differentiated memory phenotype with reduced ability to produce IL-2 and cytotoxic molecules such as granzyme B and perforin, but with strong proliferative potential. In a cohort of 28 chronic hepatitis B patients with high viral load treated with peginterferon and adefovir, HBV-specific T cells could not be detected directly ex vivo. However, HBV-specific T cells could be selectively expanded in vitro in patients with therapy-induced HBsAg clearance (HBsAg loss n=7), but not in patients without HBsAg clearance (n=21). Further analysis of HBV-specific T cell function with peptide pools showed broad and efficient antiviral responses after therapy. CONCLUSIONS Our results show that peginterferon based combination therapy can induce HBV-specific T cell restoration. These findings may help to develop novel therapeutic strategies to reconstitute antiviral functions and enhance viral clearance.


Liver International | 2015

An intrahepatic transcriptional signature of enhanced immune activity predicts response to peginterferon in chronic hepatitis B

L. Jansen; Annikki de Niet; Zuzanna Makowska; Michael T. Dill; Karel A. van Dort; Valeska Terpstra; R. Bart Takkenberg; Harry L.A. Janssen; Markus H. Heim; Neeltje A. Kootstra; Hendrik W. Reesink

Differences in intrahepatic gene expression patterns may be associated with therapy response in peginterferon‐treated chronic hepatitis B (CHB) patients.


Journal of Hepatology | 2014

HBsAg loss in patients treated with peginterferon alfa-2a and adefovir is associated with SLC16A9 gene variation and lower plasma carnitine levels

L. Jansen; Annikki de Niet; F. Stelma; Erik P.A. van Iperen; Karel A. van Dort; Marjan J. Tempelmans Plat-Sinnige; R. Bart Takkenberg; Daniel J. Chin; Aeilko H. Zwinderman; Uri Lopatin; Neeltje A. Kootstra; Hendrik W. Reesink

BACKGROUND & AIMS Achievement of HBsAg loss remains the hallmark of chronic hepatitis B treatment. In order to identify host factors contributing to treatment-induced HBsAg loss, we performed a genome-wide screen of single nucleotide polymorphisms (SNPs) and studied its immunological consequence. METHODS Chronic hepatitis B patients (40 HBeAg-positive and 44 HBeAg-negative) treated with peginterferon alfa-2a and adefovir were genotyped for 999,091 SNPs, which were associated with HBsAg loss at week 96 (n = 9). Plasma carnitine levels were measured by tandem-mass spectrometry, and the effect of carnitine on the proliferative capacity of hepatitis B virus (HBV)-specific and non-specific CD8 T cells was studied in vitro. RESULTS One polymorphism, rs12356193 located in the SLC16A9 gene, was genome-wide significantly associated with HBsAg loss at week 96 (p = 1.84 × 10(-8)). The previously reported association of rs12356193 with lower carnitine levels was confirmed in our cohort, and baseline carnitine levels were lower in patients with HBsAg loss compared to patients with HBsAg persistence (p = 0.02). Furthermore, we demonstrated that carnitine suppressed HBV-specific CD8 T cell proliferation. CONCLUSIONS In chronic hepatitis B patients treated with peginterferon and adefovir, we identified strong associations of SLC16A9 gene variation and carnitine levels with HBsAg loss. Our results further suggest that a lower baseline plasma carnitine level increases the proliferative capacity of CD8 T cells, making patients more susceptible to the immunological effect of this treatment. These novel findings may provide new insight into factors involved in treatment-induced HBsAg loss, and play a role in the prediction of treatment outcome.


European Journal of Gastroenterology & Hepatology | 2010

Detection of hepatitis B virus covalently closed circular DNA in paraffin-embedded and cryo-preserved liver biopsies of chronic hepatitis B patients.

R. Bart Takkenberg; Hans L. Zaaijer; Sandra Menting; Christine J. Weegink; Valeska Terpstra; Marion Cornelissen; Marcel G. W. Dijkgraaf; Peter L. M. Jansen; Hendrik W. Reesink; Marcel G. H. M. Beld

Background Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) may become an important predictor for treatment outcome or long-term follow-up. Aim To detect cccDNA in formalin-fixed, paraffin embedded (FFPE) and to compare with cryo-preserved liver tissue. Methods Biopsies of 56 chronic hepatitis B patients were collected. Cryo-preserved and FFPE liver biopsies were available from 37 out of 56 patients. Paraffin was extracted with 1 ml xylene, followed by 100% alcohol and acetone. For the detection of cccDNA, selective primers were used. For quantification of hepatocytes a commercial Taqman β-actin control kit was used. Results The cccDNA was detected in 80% of FFPE and in 100% of cryo-preserved liver specimens. Recovery of hepatocytes and cccDNA was approximately a 100-fold lower in FFPE liver tissue, but intrahepatic cccDNA levels were comparable. In FFPE and cryo-preserved liver tissue, intrahepatic cccDNA levels correlated strongly with HBV DNA, hepatitis B e antigen (HbeAg), and plasma cccDNA levels. HbeAg positive chronic hepatitis B patients had significantly higher intrahepatic cccDNA levels compared with HBeAg negative patients (P<0.05). In HBeAg positive patients, no difference in intrahepatic cccDNA levels were seen between patients with active (histological activity index score>3; HBV DNA>20 000 IU/ml) and inactive hepatitis (histological activity index score≤3). In HBeAg negative chronic hepatitis B patients, intrahepatic cccDNA levels were significantly higher in patients with active hepatitis (P=0.004 and 0.001). Conclusion Recovery of hepatocytes and cccDNA in FFPE tissue was lower, but intrahepatic cccDNA in FFPE biopsies were comparable with cryo-preserved liver tissue. Therefore, FFPE liver tissue is an attractive alternative for cccDNA analysis when cryo-preserved tissue is not available.


Journal of Hepatology | 2016

Ursodeoxycholic acid in advanced polycystic liver disease: A phase 2 multicenter randomized controlled trial

Hedwig d’Agnolo; Wietske Kievit; R. Bart Takkenberg; Ioana Riaño; Luis Bujanda; Myrte K. Neijenhuis; Ellen J.L. Brunenberg; Ulrich Beuers; Jesus M. Banales; Joost P. H. Drenth

BACKGROUND & AIMS Ursodeoxycholic acid (UDCA) inhibits proliferation of polycystic human cholangiocytes in vitro and hepatic cystogenesis in a rat model of polycystic liver disease (PLD) in vivo. Our aim was to test whether UDCA may beneficially affect liver volume in patients with advanced PLD. METHODS We conducted an international, multicenter, randomized controlled trial in symptomatic PLD patients from three tertiary referral centers. Patients with PLD and total liver volume (TLV) ⩾2500ml were randomly assigned to UDCA treatment (15-20mg/kg/day) for 24weeks, or to no treatment. Primary endpoint was proportional change in TLV. Secondary endpoints were change in symptoms and health-related quality of life. We performed a post-hoc analysis of the effect of UDCA on liver cyst volume (LCV). RESULTS We included 34 patients and were able to assess primary endpoint in 32 patients, 16 with autosomal dominant polycystic kidney disease (ADPKD) and 16 with autosomal dominant polycystic liver disease (ADPLD). Proportional TLV increased by 4.6±7.7% (mean TLV increased from 6697ml to 6954ml) after 24weeks of UDCA treatment compared to 3.1±3.8% (mean TLV increased from 5512ml to 5724ml) in the control group (p=0.493). LCV was not different after 24weeks between controls and UDCA treated patients (p=0.848). However, UDCA inhibited LCV growth in ADPKD patients compared to ADPKD controls (p=0.049). CONCLUSIONS UDCA administration for 24weeks did not reduce TLV in advanced PLD, but UDCA reduced LCV growth in ADPKD patients. Future studies might explore whether ADPKD and ADPLD patients respond differently to UDCA treatment. LAY SUMMARY Current therapies for polycystic liver disease are invasive and have high recurrence risks. Our trial showed that the drug, ursodeoxycholic acid, was not able to reduce liver volume in patients with polycystic liver disease. However, a subgroup analysis in patients that have kidney cysts as well showed that liver cyst volume growth was reduced in patients who received ursodeoxycholic acid in comparison to patients who received no treatment. Trial registration number https://www.clinicaltrials.gov/: NCT02021110. EudraCT Number https://www.clinicaltrialsregister.eu/: 2013-003207-19.


The Journal of Infectious Diseases | 2017

Plasma MicroRNA Levels Are Associated With Hepatitis B e Antigen Status and Treatment Response in Chronic Hepatitis B Patients

Meike H. van der Ree; Louis Jansen; Zita Kruize; Ad C. van Nuenen; Karel A. van Dort; R. Bart Takkenberg; Hendrik W. Reesink; Neeltje A. Kootstra

Background Hepatitis B virus (HBV) modulates microRNA (miRNA) expression to support viral replication. The aim of this study was to identify miRNAs associated with hepatitis B e antigen (HBeAg) status and response to antiviral therapy in patients with chronic hepatitis B (CHB) , and to assess if these miRNAs are actively secreted by hepatoma cells. Methods Plasma miRNA levels were measured by reverse-transcription quantitative polymerase chain reaction in healthy controls (n = 10) and pretreatment samples of an identification cohort (n = 24) and a confirmation cohort (n = 64) of CHB patients treated with peginterferon/nucleotide analogue combination therapy. Levels of HBV-associated miRNAs were measured in cells, extracellular vesicles, and hepatitis B surface antigen (HBsAg) particles of hepatoma cell lines. Results HBeAg-positive patients had higher plasma levels of miR-122-5p, miR-125b-5p, miR-192-5p, miR-193b-3p, and miR-194-5p compared to HBeAg-negative patients, and levels of these miRNAs were associated with HBV DNA and HBsAg levels. Pretreatment plasma levels of miR-301a-3p and miR-145-5p were higher in responders (combined response or HBsAg loss) compared to nonresponders. miR-192-5p, miR-193b-3p, and miR-194-5p were present in extracellular vesicles and HBsAg particles derived from hepatoma cells. Conclusions We identified miRNAs that are associated with HBeAg status, levels of HBV DNA and HBsAg, and treatment response in CHB patients. We demonstrated that several of these miRNAs are present in extracellular vesicles and HBsAg particles secreted by hepatoma cells.


Antiviral Research | 2017

Viral minority variants in the core promoter and precore region identified by deep sequencing are associated with response to peginterferon and adefovir in HBeAg negative chronic hepatitis B patients

L. Jansen; Matthijs R.A. Welkers; Karel A. van Dort; R. Bart Takkenberg; Uri Lopatin; Hans L. Zaaijer; Menno D. de Jong; Hendrik W. Reesink; Neeltje A. Kootstra

Background and aim: Precore (PC) and basal core promoter (BCP) mutations are associated with responses to interferon‐based treatment in HBeAg‐positive chronic hepatitis B (CHB) patients. Here, we identify viral minority variants in these regions and assess association with response to peginterferon‐alfa (Peg‐IFN) and adefovir combination therapy. Patients and methods: Ultra‐deep pyrosequencing analysis of the BCP and PC region was performed for 89 CHB patients (42 HBeAg‐positive; 47 HBeAg‐negative), at baseline and during treatment. Specifically, associations of individual positions with the HBeAg‐negative phenotype were studied, as well as the association of the most prevalent mutations with combined response in HBeAg‐positive and –negative patients at week 72 (HBeAg negativity, HBV‐DNA <2000 IU/mL and ALT normalization at 24 weeks of treatment‐free follow‐up). Results: The mutations most strongly correlated with the HBeAg‐negative phenotype were at positions 1762/1764 and 1896/1899 in the BCP and PC region, respectively. No major changes in nucleotide composition of these positions were observed during treatment. In HBeAg‐negative patients, a combined presence of 1764A and 1896A was correlated with lower ALT levels (p = 0.004), whereas the presence of 1899A was correlated with higher age (p = 0.030), lower HBV‐DNA level (p = 0.036), and previous IFN therapy (p = 0.032). The presence of 1764A/1896A or the absence of 1899A at baseline, was associated with lower response rates, after adjustment for HBV genotype (p = 0.031 and p = 0.017) and HBsAg level (p = 0.035 and p = 0.022). Conclusion: We identified novel correlations between common BCP and PC variants with response to Peg‐IFN and adefovir in HBeAg‐negative patients. Ultimately, this may guide the selection of those patients most likely to benefit from Peg‐IFN‐based treatment.


Hepatology Research | 2012

Factor XIII Val34Leu mutation accelerates the development of fibrosis in patients with chronic hepatitis B and C

Kathelijne Dik; Joep de Bruijne; R. Bart Takkenberg; Joris J. T. H. Roelofs; Marjan J. Tempelmans; Marcel G. W. Dijkgraaf; Huub C. Gelderblom; Henk W. Reesink; Joost C. M. Meijers; Peter L. M. Jansen; Marcel Levi

Aim:  There is considerable variation in liver fibrosis stage and progression to cirrhosis among patients with chronic hepatitis B (CHB) or C (CHC). Coagulation pathway activity due to genetic variations could influence the rate of fibrosis. We investigated thrombotic risk factors and their association with the extent and progression of fibrosis in CHB or CHC patients.

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F. Stelma

University of Amsterdam

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Louis Jansen

Academic Medical Center

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L. Jansen

University of Amsterdam

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