Netherlands Vaccine Institute

Bilthoven, Netherlands

Netherlands Vaccine Institute

Bilthoven, Netherlands
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Hirschberg H.J.H.B.,Netherlands Vaccine Institute | van de Wijdeven G.G.P.,Bioneedle Technologies Group BV | Kraan H.,Netherlands Vaccine Institute | Amorij J.-P.,Netherlands Vaccine Institute | Kersten G.F.A.,Netherlands Vaccine Institute
Journal of Controlled Release | Year: 2010

An alternative vaccine delivery system for needle injections is the Bioneedle. Hepatitis B surface antigen (HBsAg) was formulated with Bioneedles. Three formulations were used: plain antigen, HBsAg adjuvated with aluminum hydroxide and HBsAg with LPS-derived lpxL1. Bioneedles with HBsAg-. lpxL1 were the most stable and the most immunogenic formulations. The conventional liquid alum adjuvated vaccine lost 40% of its antigenicity after 1. week at 50°C whereas the HBsAg-. lpxL1 Bioneedles showed no significant decrease after 3. weeks at 50°C. In vivo studies revealed that the HBsAg-. lpxL1 Bioneedle formulations induced comparable IgG titers as conventional liquid formulations after 2 immunizations, but higher IgG2a titers were found already after 1 immunization. The in vivo and in vitro studies showed that the Bioneedle is an attractive alternative for needle injections of HBsAg vaccines. © 2010 Elsevier B.V.

Bal S.M.,Leiden University | Slutter B.,Leiden University | van Riet E.,Leiden University | Kruithof A.C.,Leiden University | And 4 more authors.
Journal of Controlled Release | Year: 2010

The function of N-trimethyl chitosan (TMC) in dermal immunisation is unknown. Therefore we investigated the immunogenicity of both antigen-containing TMC nanoparticles and TMC/antigen solutions after intradermal injection. Nanoparticles were prepared with a size around 200 nm and a positive zetapotential. In vitro, TMC nanoparticles increased the uptake of OVA by dendritic cells (DCs) and both nanoparticles and TMC/OVA mixtures were able to induce upregulation of MHC-II, CD83 and CD86. These activated DCs could induce a Th2 biased T cell proliferation. A solution of plain OVA did not induce DC maturation or T cell proliferation. In vivo, mice were injected thrice with TMC based formulations containing either OVA or diphtheria toxoid (DT), a more relevant antigen. All TMC-containing formulations were able to increase the IgG titres compared to unadjuvanted antigen and induced a Th2 biased immune response. When using DT-containing TMC formulations, IgG titres and neutralising antibody titres could match up to those obtained after subcutaneous injection of DT-Alum. In conclusion, both soluble TMC/antigen mixtures and TMC nanoparticles are able to induce DC maturation and enhance immune responses after intradermal injection. This demonstrates that TMC functions as an immune potentiator for antigens delivered via the skin. © 2009 Elsevier B.V. All rights reserved.

Kaaijk P.,National Institute for Public Health and the Environment | Van Der Ark A.A.J.,National Institute for Public Health and the Environment | Van Amerongen G.,Netherlands Vaccine Institute | Van Den Dobbelsteen G.P.J.M.,National Institute for Public Health and the Environment
Journal of Applied Toxicology | Year: 2013

Fever has been reported as the most common adverse event after vaccination in infants and children. For this reason it is important that, prior to clinical testing of a new vaccine, change in body temperature following vaccination is tested carefully in nonclinical animal studies. Since both the timing and the height of the temperature peak after vaccination may differ from vaccine to vaccine, it is important that the time point for body temperature measurement should be chosen on a case-by-case basis with sufficient knowledge of the specific vaccine. In order to determine the best time point for rectal body temperature measurement after vaccination with a new vaccine candidate against N. meningitidis serogroup B, to be applied in a formal Good Laboratory Practice (GLP) toxicology study, miniature temperature data loggers were implanted into the peritoneal cavity of rabbits. The continuous body temperature monitoring appeared to give a complete picture of the entire body temperature kinetics after vaccination. The body temperature peaked at 4h after vaccination, and this time point was subsequently applied in the toxicology study. Measured body temperature values at the selected time point of 4h after vaccination were comparable in the continuous temperature setting and in the formal toxicology study, i.e. rectal temperature measurement at one time point. In the present study implanted temperature loggers were successfully used to define an adequate time point to be applied in determining rectal body temperature in a formal GLP toxicology study with a new vaccine candidate. Copyright © 2012 John Wiley & Sons, Ltd.

Schiffelers M.-J.W.A.,University Utrecht | Blaauboer B.J.,University Utrecht | Hendriksen C.F.M.,Netherlands Vaccine Institute | Bakker W.E.,University Utrecht
Altex | Year: 2012

The importance placed on risk avoidance in our society has resulted in a broad range of regulations intended to guarantee safety of products such as pharmaceuticals and chemicals. Many of these regulations rely on animal tests. As a result, about 25% of the animal experiments in Europe are done for regulatory purposes. There are many initiatives that aim to replace, reduce, or refine laboratory animal use, but the regulatory acceptance and use of 3R models lags behind. The central question of this study is: "Which variables influence the regulatory acceptance and use of 3R models and in what way?" Regulatory acceptance is seen as one of the biggest hurdles 3R models face, but the rationale behind this is still underexplored. This study is an approach to filling that gap by combining opinions from experts in the field with literature on technology acceptance and risk regulation, resulting in a model of the variables that determine the process of the regulatory acceptance and use of 3R models.

Saluja V.,University of Groningen | Amorij J.-P.,University of Groningen | Amorij J.-P.,Netherlands Vaccine Institute | Kapteyn J.C.,Solvay Group | And 3 more authors.
Journal of Controlled Release | Year: 2010

The aim of this study was to investigate two different processes to produce a stable influenza subunit vaccine powder for pulmonary immunization i.e. spray drying (SD) and spray freeze drying (SFD). The formulations were analyzed by proteolytic assay, single radial immunodiffusion assay (SRID), cascade impactor analysis, and immunization studies in Balb/c mice. Proteolytic assay and SRID analysis showed that antigen integrity after SFD was best conserved when the formulation was buffered by Hepes buffer saline (HBS). Surprisingly, antigen integrity after SD was better conserved when the formulation was buffered by phosphate buffer saline (PBS) rather than by HBS. The dispersion from the dry powder inhaler, the Twincer®, resulted in a fine particle fraction (aerodynamic particle size <5μm) of 37% and 23% for spray dried and spray freeze dried powders, respectively. Immunogenicity of both vaccine formulations (SFD/HBS and SD/PBS) was similar to conventional liquid formulation after i.m. immunization. In addition, compared to i.m. immunizations, the pulmonary immunization with the dry powders resulted in significantly higher IgG titers. Furthermore, both the formulations remained biochemically and physically stable for at least 3years of storage at 20°C. Our results demonstrate that both optimized formulations are stable and have good inhalation characteristics. © 2010 Elsevier B.V.

Thomassen Y.E.,Netherlands Vaccine Institute | Van Sprang E.N.M.,Toegepaste Industriele Procesbeheersing | Van Der Pol L.A.,Netherlands Vaccine Institute | Bakker W.A.M.,Netherlands Vaccine Institute
Biotechnology and Bioengineering | Year: 2010

Historical manufacturing data can potentially harbor a wealth of information for process optimization and enhancement of efficiency and robustness. To extract useful data multivariate data analysis (MVDA) using projection methods is often applied. In this contribution, the results obtained from applying MVDA on data from inactivated polio vaccine (IPV) production runs are described. Data fromover 50 batches at two different production scales (700-L and 1,500-L) were available. The explorative analysis performed on single unit operations indicated consistent manufacturing. Known outliers (e.g., rejected batches) were identified using principal component analysis (PCA). The source of operational variation was pinpointed to variation of input such as media. Other relevant process parameters were in control and, using this manufacturing data, could not be correlated to product quality attributes. The gained knowledge of the IPV production process, not only from the MVDA, but also from digitalizing the available historical data, has proven to be useful for troubleshooting, understanding limitations of available data and seeing the opportunity for improvements. © 2010 Wiley Periodicals, Inc.

Amorij J.-P.,University of Groningen | Amorij J.-P.,Netherlands Vaccine Institute | Hinrichs W.L.J.,University of Groningen | Frijlink H.W.,University of Groningen | And 2 more authors.
The Lancet Infectious Diseases | Year: 2010

Vaccination is the cornerstone of influenza control in epidemic and pandemic situations. Influenza vaccines are typically given by intramuscular injection. However, needle-free vaccinations could offer several distinct advantages over intramuscular injections: they are pain-free, easier to distribute, and easier to give to patients, and their use could reduce vaccination costs. Moreover, vaccine delivery via the respiratory tract, alimentary tract, or skin might elicit mucosal immune responses at the site of virus entry and better cellular immunity, thus improving effectiveness. Although various needle-free vaccination methods for influenza have shown preclinical promise, few have progressed to clinical trials-only live attenuated intranasal vaccines have received approval, and only in some countries. Further clinical investigation is needed to help realise the potential of needle-free vaccination for influenza. © 2010 Elsevier Ltd.

Bal S.M.,Leiden University | Ding Z.,Leiden University | Kersten G.F.A.,Netherlands Vaccine Institute | Jiskoot W.,Leiden University | Bouwstra J.A.,Leiden University
Pharmaceutical Research | Year: 2010

Purpose: The purpose of this study was to gain insight into the delivery and immunogenicity of N-trimethyl chitosan (TMC) adjuvanted diphtheria toxoid (DT) formulations applied transcutaneously with microneedles. Methods: Mice were vaccinated with DT-loaded TMC nanoparticles, a solution of TMC and DT (TMC/DT) or DT alone. The formulations were applied onto the skin before or after microneedle treatment with two different 300-μm-long microneedle arrays and also injected intradermally (ID). As a positive control, alum-adjuvanted DT (DT-alum) was injected subcutaneously (SC). Ex vivo confocal microscopy studies were performed with rhodamine-labelled TMC. Results: Independent of the microneedle array used and the sequence of microneedle treatment and vaccine application, transcutaneous immunisation with the TMC/DT mixture elicited 8-fold higher IgG titres compared to the TMC nanoparticles or DT solution. The toxin-neutralising antibody titres from this group were similar to those elicited by SC DT-alum. After ID immunisation, both TMC-containing formulations induced enhanced titres compared to a DT solution. Confocal microscopy studies revealed that transport of the TMC nanoparticles across the microneedle conduits was limited compared to a TMC solution. Conclusions: In conclusion, TMC has an adjuvant function in transcutaneous immunisation with microneedles, but only if applied in a solution. © 2010 The Author(s).

BACKGROUND: Respiratory syncytial virus (RSV) is a primary cause of serious lower respiratory tract illness for which there is still no safe and effective vaccine available. Using reverse genetics, recombinant (r)RSV and an rRSV lacking the G gene (DeltaG) were constructed based on a clinical RSV isolate (strain 98-25147-X). RESULTS: Growth of both recombinant viruses was equivalent to that of wild type virus in Vero cells, but was reduced in human epithelial cells like Hep-2. Replication in cotton rat lungs could not be detected for DeltaG, while rRSV was 100-fold attenuated compared to wild type virus. Upon single dose intranasal administration in cotton rats, both recombinant viruses developed high levels of neutralizing antibodies and conferred comparable long-lasting protection against RSV challenge; protection against replication in the lungs lasted at least 147 days and protection against pulmonary inflammation lasted at least 75 days. CONCLUSION: Collectively, the data indicate that a single dose immunization with the highly attenuated DeltaG as well as the attenuated rRSV conferred long term protection in the cotton rat against subsequent RSV challenge, without inducing vaccine enhanced pathology. Since DeltaG is not likely to revert to a less attenuated phenotype, we plan to evaluate this deletion mutant further and to investigate its potential as a vaccine candidate against RSV infection.

Venhuis B.J.,National Institute for Public Health and the Environment | Zomer G.,Netherlands Vaccine Institute | Vredenbregt M.J.,National Institute for Public Health and the Environment | de Kaste D.,National Institute for Public Health and the Environment
Journal of Pharmaceutical and Biomedical Analysis | Year: 2010

Four blisters with suspect Cialis® (tadalafil) 20 mg tablets were screened for authenticity using near infrared spectroscopy (NIRS) and for the presence of phosphodiesterase 5 (PDE-5) inhibitors using LC-DAD-MS. All samples were identified as counterfeit Cialis® and contained sildenafil or a combination of tadalafil and sildenafil. Although the tablets contained efficacious amounts of PDE-5 inhibitors, neither the active ingredient nor the dosage corresponded to the description on the blister. This is the first reported case of a diastereomeric mixture of tadalafil and trans-tadalafil (3:1) being identified in a counterfeit medicine. The LC-DAD-CD revealed that both diastereomers had a high optical purity. The optical rotation of the diastereomeric mixture was measured indicating the presence of (-)-trans-tadalafil, which is the only other stereoisomer with some PDE-5 inhibitory activity. As no safety profiles are known for the stereoisomers of tadalafil, there is a potential health risk. In addition, the optical purity of tadalafil needs to be taken into account when calculating the dosage in illegal medicines. © 2009.

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