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Featured researches published by F. Stelma.


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.


Scientific Reports | 2017

Human intrahepatic CD69 + CD8+ T cells have a tissue resident memory T cell phenotype with reduced cytolytic capacity

F. Stelma; Annikki de Niet; M.J. Sinnige; Karel A. van Dort; Klaas P. J. M. van Gisbergen; Joanne Verheij; Ester M. M. van Leeuwen; Neeltje A. Kootstra; Hendrik W. Reesink

Tissue resident memory T cells (TRM) have been identified in various tissues, however human liver TRM to date remain unidentified. TRM can be recognized by CD69 and/or CD103 expression and may play a role in the pathology of chronic hepatitis B (CHB) and hepatitis C virus infection (CHC). Liver and paired blood mononuclear cells from 17 patients (including 4 CHB and 6 CHC patients) were isolated and CD8+ T cells were comprehensively analysed by flowcytometry, immunohistochemistry and qPCR. The majority of intrahepatic CD8+ T cells expressed CD69, a marker used to identify TRM, of which a subset co-expressed CD103. CD69 + CD8+ T cells expressed low levels of S1PR1 and KLF2 and a large proportion (>90%) was CXCR6+, resembling liver TRM in mice and liver resident NK cells in human. Cytotoxic proteins were only expressed in a small fraction of liver CD69 + CD8+ T cells in patients without viral hepatitis, however, in livers from CHB patients more CD69 + CD8+ T cells were granzyme B+. In CHC patients, less intrahepatic CD69 + CD8+ T cells were Hobit+ as compared to CHB and control patients. Intrahepatic CD69 + CD8+ T cells likely TRM which have a reduced cytolytic potential. In patients with chronic viral hepatitis TRM have a distinct phenotype.


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.


Journal of Hepatology | 2015

LO7 : A single subcutaneous dose of 2mg/kg or 4mg/kg of RG-101, a GalNAc-conjugated oligonucleotide with antagonist activity against MIR-122, results in significant viral load reductions in chronic hepatitis C patients

M.H. van der Ree; M. de Vree; F. Stelma; S.B. Willemse; M. van der Valk; S. Rietdijk; Richard Molenkamp; Janke Schinkel; S. Hadi; M. Harbers; A. van Vliet; J. Udo de Haes; P. Grint; S. Neben; Neil W. Gibson; H.W. Reesink

GWAS hits were validated in independent cohorts from Germany (529 cases vs. 761 controls) and Belgium (619 cases vs. 161 controls) and the results of the joint analyses combined. Genotyping was undertaken using Illumina BeadChips (Illumina Inc., San Diego, CA, USA); SNP replication was undertaken using Taqman chemistry (Applied Biosystems, Foster City, Ca, USA) on an automated platform. Results: The strongest association signal in the initial metaanalysis was observed between the rs738409 variant in PNPLA3 (Pmeta =1.17×10−28, OR=2.38 [2.08–2.69]); 102 separate variants at the PNPLA3 locus associated with genome-wide significance (Pthreshold <5×10−8). In addition, nine other independent loci provided borderline association signals (Pthreshold ≤1.1×10−5). Validation genotyping for rs738409 in PNPLA3 and lead markers for the top 10 associated regions confirmed disease association for rs738409 in PNPLA3, and for (MBOAT7: rs641738 Preplication = 1.35×10−4; Pcombined = 9.25×10−10; OR=1.63 [1.46–1.80] and TM6SF2: rs10401969 Preplication = 3.29×10−5; Pcombined = 1.73×10−8; OR=1.35 [1.25–1.44]).


Hepatology | 2017

Immune phenotype and function of natural killer and T cells in chronic hepatitis C patients who received a single dose of anti‐MicroRNA‐122, RG‐101

F. Stelma; Meike H. van der Ree; M.J. Sinnige; Anthony Brown; Leo Swadling; J. Marleen L. de Vree; S.B. Willemse; Marc van der Valk; P. Grint; S. Neben; Paul Klenerman; Eleanor Barnes; Neeltje A. Kootstra; Hendrik W. Reesink

MicroRNA‐122 is an important host factor for the hepatitis C virus (HCV). Treatment with RG‐101, an N‐acetylgalactosamine‐conjugated anti‐microRNA‐122 oligonucleotide, resulted in a significant viral load reduction in patients with chronic HCV infection. Here, we analyzed the effects of RG‐101 therapy on antiviral immunity. Thirty‐two chronic HCV patients infected with HCV genotypes 1, 3, and 4 received a single subcutaneous administration of RG‐101 at 2 mg/kg (n = 14) or 4 mg/kg (n = 14) or received a placebo (n = 2/dosing group). Plasma and peripheral blood mononuclear cells were collected at multiple time points, and comprehensive immunological analyses were performed. Following RG‐101 administration, HCV RNA declined in all patients (mean decline at week 2, 3.27 log10 IU/mL). At week 8 HCV RNA was undetectable in 15/28 patients. Plasma interferon‐γ‐induced protein 10 (IP‐10) levels declined significantly upon dosing with RG‐101. Furthermore, the frequency of natural killer (NK) cells increased, the proportion of NK cells expressing activating receptors normalized, and NK cell interferon‐γ production decreased after RG‐101 dosing. Functional HCV‐specific interferon‐γ T‐cell responses did not significantly change in patients who had undetectable HCV RNA levels by week 8 post–RG‐101 injection. No increase in the magnitude of HCV‐specific T‐cell responses was observed at later time points, including 3 patients who were HCV RNA–negative 76 weeks postdosing. Conclusion: Dosing with RG‐101 is associated with a restoration of NK‐cell proportions and a decrease of NK cells expressing activation receptors; however, the magnitude and functionality of ex vivo HCV‐specific T‐cell responses did not increase following RG‐101 injection, suggesting that NK cells, but not HCV adaptive immunity, may contribute to HCV viral control following RG‐101 therapy. (Hepatology 2017;66:57–68).


The Lancet Gastroenterology & Hepatology | 2017

Peg-interferon plus nucleotide analogue treatment versus no treatment in patients with chronic hepatitis B with a low viral load: a randomised controlled, open-label trial

Annikki de Niet; Louis Jansen; F. Stelma; S.B. Willemse; Sjoerd D. Kuiken; Sebastiaan Weijer; Carin M. J. van Nieuwkerk; Hans L. Zaaijer; Richard Molenkamp; R. Bart Takkenberg; M. Koot; Joanne Verheij; Ulrich Beuers; Hendrik W. Reesink

BACKGROUND Antiviral treatment is currently not recommended for patients with chronic hepatitis B with a low viral load. However, they might benefit from acquiring a functional cure (hepatitis B surface antigen [HBsAg] loss with or without formation of antibodies against hepatitis B surface antigen [anti-HBs]). We assessed HBsAg loss during peg-interferon-alfa-2a (peg-IFN) and nucleotide analogue combination therapy in patients with chronic hepatitis B with a low viral load. METHODS In this randomised controlled, open-label trial, patients were enrolled from the Academic Medical Center (AMC), Amsterdam, Netherlands. Eligible patients were HBsAg positive and hepatitis B e antigen (HBeAg) negative for more than 6 months, could be treatment naive or treatment experienced, and had alanine aminotransferase (ALT) concentrations less than 5 × upper limit of normal (ULN). Participants were randomly assigned (1:1:1) by a computerised randomisation programme (ALEA Randomisation Service) to receive peg-IFN 180 μg/week plus adefovir 10 mg/day, peg-IFN 180 μg/week plus tenofovir disoproxil fumarate 245 mg/day, or no treatment for 48 weeks. The primary endpoint was the proportion of patients with serum HBsAg loss among those who received at least one dose of study drug or had at least one study visit (modified intention-to-treat population [mITT]). All patients have finished the initial study of 72 weeks and will be observed for up to 5 years of follow-up. This study is registered with ClinicalTrials.gov, number NCT00973219. FINDINGS Between Aug 4, 2009, and Oct 17, 2013, 167 patients were screened for enrolment, of whom 151 were randomly assigned (52 to peg-IFN plus adefovir, 51 to peg-IFN plus tenofovir, and 48 to no treatment). 46 participants in the peg-IFN plus adefovir group, 45 in the peg-IFN plus tenofovir group, and 43 in the no treatment group began treatment or observation and were included in the mITT population. At week 72, two (4%) patients in the peg-IFN plus adefovir group and two (4%) patients in the peg-IFN plus tenofovir group had achieved HBsAg loss, compared with none of the patients in the no treatment group (p=0·377). The most frequent adverse events (>30%) were fatigue, headache, fever, and myalgia, which were attributed to peg-IFN dosing. Two (4%) serious adverse events were reported in the peg-IFN plus adefovir group (admission to hospital for alcohol-related pancreatitis [week 6; n=1] and pregnancy, which was electively aborted [week 9; n=1]), three (7%) in the peg-IFN plus tenofovir group (admission to hospital after a suicide attempt during a severe depression [week 23; n=1], admission to hospital for abdominal pain [week 2; n=1], and an elective laminectomy [week 40; n=1]), and three (7%) in the no treatment group (admission to hospital for septic arthritis [week 72; n=1], endocarditis [week 5; n=1], and hyperthyroidism [week 20; n=1]). INTERPRETATION In patients with chronic hepatitis B with a low viral load, combination treatment (peg-IFN plus adefovir and peg-IFN plus tenofovir) did not result in significant HBsAg loss compared with no treatment, which does not support the use of combination treatment in this population of patients. FUNDING Roche, Fonds NutsOhra.


Journal of Viral Hepatitis | 2016

HLA-C and KIR combined genotype as new response marker for HBeAg-positive chronic hepatitis B patients treated with interferon-based combination therapy

F. Stelma; L. Jansen; M.J. Sinnige; K. A. van Dort; R.B. Takkenberg; H.L.A. Janssen; H.W. Reesink; Neeltje A. Kootstra

Current treatment for chronic hepatitis B infection (CHB) consists of interferon‐based therapy. However, for unknown reasons, a large proportion of patients with CHB do not respond to this treatment. Hence, there is a pressing need to establish response markers to select patients who will benefit from therapy and to spare potential nonresponders from unnecessary side effects of antiviral therapy. Here, we assessed whether HLA‐C and KIR genotypes were associated with treatment outcome for CHB. Twelve SNPs in or near the HLA‐C gene were genotyped in 86 CHB patients (41 HBeAg positive; 45 HBeAg negative) treated with peginterferon alfa‐2a + adefovir. Genotyping of killer immunoglobin‐like receptors (KIRs) was performed by SSP‐PCR. One SNP in HLA‐C (rs2308557) was significantly associated with combined response in HBeAg‐positive CHB patients (P = 0.003). This SNP is linked to the HLA‐C group C1 or C2 classification, which controls KIR binding. The combination of KIR2DL1 with its ligand HLA‐C2 was observed significantly more often in HBeAg‐positive patients with a combined response (13/14) than in nonresponders (11/27, P = 0.001). Patients with the KIR2DL1/C2 genotype had significantly higher baseline ALT levels (136 vs 50 U/L, P = 0.002) than patients without this combination. Furthermore, KIR2DL1‐C2 predicted response independent of HBV genotype and ALT at baseline. HLA‐C and KIR genotype is strongly associated with response in HBeAg‐positive CHB patients treated with interferon‐based therapy. In combination with other known response markers, HLA‐C/KIR genotype could enable the selection of patients more likely to respond to interferon‐based therapy.


Antiviral Research | 2017

Immune responses in DAA treated chronic hepatitis C patients with and without prior RG-101 dosing

Meike H. van der Ree; F. Stelma; S.B. Willemse; Anthony Brown; Leo Swadling; Marc van der Valk; M.J. Sinnige; Ad C. van Nuenen; J. Marleen L. de Vree; Paul Klenerman; Eleanor Barnes; Neeltje A. Kootstra; Hendrik W. Reesink

Background&aims: With the introduction of DAAs, the majority of treated chronic hepatitis C patients (CHC) achieve a viral cure. The exact mechanisms by which the virus is cleared after successful therapy, is still unknown. The aim was to assess the role of the immune system and miRNA levels in acquiring a sustained virological response after DAA treatment in CHC patients with and without prior RG‐101 (anti‐miR‐122) dosing. Methods: In this multicenter, investigator‐initiated study, 29 patients with hepatitis C virus (HCV) genotype 1 (n = 11), 3 (n = 17), or 4 (n = 1) infection were treated with sofosbuvir and daclatasvir ± ribavirin. 18 patients were previously treated with RG‐101. IP‐10 levels were measured by ELISA. Ex vivo HCV‐specific T cell responses were quantified in IFN‐&ggr;‐ELISpot assays. Plasma levels of miR‐122 were measured by qPCR. Results: All patients had an SVR12. IP‐10 levels rapidly declined during treatment, but were still elevated 24 weeks after treatment as compared to healthy controls (median 53.82 and 39.4 pg/mL, p = 0.02). Functional IFN‐&ggr; HCV‐specific T cell responses did not change by week 12 of follow‐up (77.5 versus 125 SFU/106 PBMC, p = 0.46). At follow‐up week 12, there was no difference in plasma miR‐122 levels between healthy controls and patients with and without prior RG‐101 dosing. Conclusions: Our data shows that successful treatment of CHC patients with and without prior RG‐101 dosing results in reduction of broad immune activation, and normalisation of miR‐122 levels (EudraCT: 2014‐002808‐25). Trial registration: EudraCT: 2014‐002808‐25. HighlightsDAA treatment is highly effective in chronic hepatitis C patients with and without prior anti‐miR‐122 treatment.Successful treatment of chronic hepatitis C patients results in reduction of broad immune activation.There is no restoration of HCV adaptive immunity after SVR in chronic hepatitis C patients.Plasma miR‐122 levels normalise after successful treatment of chronic hepatitis C virus infection.


Open Forum Infectious Diseases | 2017

Dynamics of the Immune Response in Acute Hepatitis B Infection

F. Stelma; S.B. Willemse; Robin Erken; Annikki de Niet; M.J. Sinnige; Karel A. van Dort; Hans L. Zaaijer; Ester M. M. van Leeuwen; Neeltje A. Kootstra; Hendrik W. Reesink

Abstract Background Acute hepatitis B virus infection in adults is generally self-limiting but may lead to chronicity in a minority of patients. Methods We included 9 patients with acute hepatitis B virus (HBV) infection and collected longitudinal follow-up samples. Natural killer (NK) cell characteristics were analyzed by flowcytometry. HBV-specific T-cell function was analyzed by in vitro stimulation with HBV peptide pools and intracellular cytokine staining. Results Median baseline HBV DNA load was 5.12 log IU/mL, and median ALT was 2652 U/mL. Of 9 patients, 8 cleared HBsAg within 6 months whereas 1 patient became chronically infected. Early time points after infection showed increased CD56bright NK cells and an increased proportion of cells expressing activation markers. Most of these had normalized at week 24, while the proportion of TRAIL-positive CD56bright NK cells remained high in the chronically infected patient. In patients who cleared HBV, functional HBV-specific CD8+ and CD4+ responses could be observed, whereas in the patient who developed chronic infection, only low HBV-specific T-cell responses were observed. Conclusions NK cells are activated early in the course of acute HBV infection. Broad and multispecific T-cell responses are observed in patients who clear acute HBV infection, but not in a patient who became chronically infected.

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H.W. Reesink

Academic Medical Center

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L. Jansen

University of Amsterdam

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P. Grint

Regulus Therapeutics

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