June 2024: Zebrafish and nematodes as whole organism models to measure developmental neurotoxicity
In line with the review written in May (see below), researchers from RIVM and the Vrije Universiteit have written a review about the added value of zebrafish embryos and nematodes for studying developmental neurotoxicity. They specifically outline the gaps that these whole organisms can fill in the current testing strategy for developmental neurotoxicity, such as network formation in the brain, motor function and learning and memory, contributing to the 3R (Refine, Reduce, Replace) principles. These models can provide the necessary whole organismcontext and be used to explore the impact of chemicals on brain function by linking molecular and/or cellular changes to behavioural readouts in one model system.
June 2024: How to optimize communication about animal and animal-free research methods
There is a long-standing debate about animal and animal-free methods in scientific research. In this essay, researchers that were selected by media on the topic as ‘opponents’ describe anecdotes including their initial rational thoughts and emotions after these media events. Common ground was found in the principles of good scientific practice and responsible research. The teaming up of the scientists with seemingly opposing positions was as such instrumental in improving communication on animal(-free) experimentation issues. The authors, among whom RIVM researchers, strongly believe that keeping in dialogue is essential for making well-informed decisions on what methods the scientific community is using now and will be using in the future.
May 2024: New approach methods to assess developmental and adult neurotoxicity for regulatory use: a PARC work package 5 project
In the European regulatory context, rodent studies are the main source of neurotoxicity information. There is a scientific and societal push toward the replacement of animal models with New Approach Methodologies (NAMs). This paper describes the upcoming activities to develop and evaluate NAMs for developmental neurotoxicity and adult neurotoxicity and to understand the applicability domain of specific NAMs for the detection of endocrine disruption and epigenetic perturbation. These activities will take place in the EU (European Union)-funded Partnership for the Assessment of Risk from Chemicals (PARC) of which RIVM is part.
May 2024: How neurobehavior and brain development in alternative whole-organism models can contribute to prediction of developmental neurotoxicity
Developmental neurotoxicity (DNT) testing is currently mainly performed in mammals, which has ethical issues and scientific limitations. Researchers from RIVM, Vrije Universiteit and Swarthmore College have written a review about the added value of whole organism systems that qualify as 3R (Replace, Reduce and Refine) models, which are urgently needed to complement cell-based DNT testing. The nematode Caenorhabditis elegans, the planarian Dugesia japonica, and embryos of the zebrafish Danio rerio are all suited for high-throughput screening of DNT and each of these organisms have unique strengths. The researchers also discuss how combining these models in testing strategies that consider the complexity of the developing brain will contribute to better human-relevant risk assessment of chemicals.
April 2024: New approach methodologies to enhance human health risk assessment of immunotoxic properties of chemicals — a PARC project
Chemicals may adversely affect the immune system through various pathways, leading to immune suppression, hypersensitivity, or increased susceptibility to autoimmune diseases. Currently, the evaluation of immunotoxicity by regulatory bodies relies on rodent models and a limited set of OECD test guidelines. However these guidelines do not fully encompass the full spectrum of potential immunotoxic effects. This paper offers an overview of ongoing endeavours aimed at devising and standardising new methods, both in vivo as well as new approach methodologies (NAMs) for thoroughly characterising the immunotoxic impact of chemicals. This review was established in the EU-funded Partnership for the Assessment of Risk from Chemicals (PARC). of which RIVM is part.
April 2024: A roadmap towards a human-centric safety assessment of advanced therapy medicinal products (ATMPs)
ATMPs are among the most complex pharmaceuticals. Due to their high human specificity, the clinical relevance of data derived from animal studies is limited. Researchers from CBG and RIVM surveyed stakeholders involved in ATMP development about their perspective on the use of animal studies and New Approach Methodologies (NAMs), perceived hurdles and potential solutions towards non-clinical human-centric safety assessment of ATMPs. Based on these outcomes, a roadmap was established that displays key points to consider when deciding on the need for future in vivo studies and improving the implementation of NAM-based approaches for products within a well-known modality or technology platform.
April 2024: In Vitro Assessment of Translocation and Toxicological Effects of Nicotine and Ethyl Maltol from e-Cigarettes Using Air–Liquid Interface-Cultured Bronchial Epithelial Cells
The use of e-cigarettes increases rapidly. Still, only little information is available on the adverse effects of flavourings in e-cigarettes. Toxicity testing of these flavourings in animal studies is unethical, and therefore, animal-free methods are required. RIVM researchers used cell models of the lungs to determine the toxic effects of e-cigarette vapour with nicotine and ethyl maltol. Both compounds were found to induce an inflammatory response in lung cells. They were also able to cross the lung barrier, meaning that they could enter the bloodstream and reach other organs in the human body.
April 2024: New Approach Methodologies (NAMs) for ad hoc human health risk assessment of food and non-food products - Proceedings of a workshop
RIVM convened a workshop on the use of NAMs for ad hoc human health risk assessment. Two case studies were discussed: the botanical Tabernanthe iboga, which is associated with cardiotoxicity, and dermal creams containing female sex hormones, intended for use by perimenopausal women without medical supervision. The participants recognised that data from NAMs added valuable information for the ad hoc risk assessment of these products, although the available approaches were inadequate to derive health-based guidance values. Recommendations were provided on how to further enhance and implement NAM approaches in regulatory risk assessment, specifying scientific, technical aspects and stakeholder engagement aspects.
March 2024: Landscape New Approach Methodologies (NAMs) safety assessment pharmaceutical products
Regulatory safety testing of pharmaceuticals currently needs animal studies. In the last decades, increasing attention is being given to the use of New Approach Methodologies (NAMs) to reduce animal testing. Implementation of NAMs in pharmaceutical safety assessment involves different steps and requires engagement of different stakeholders. RIVM researchers, in collaboration with the Dutch Medical Evaluation Board, made an overview of steps to take to implement NAMs for regulatory safety testing. With this overview, the researchers envision to facilitate the uptake of NAMs in this field.
March 2024: The role of trust in the use of artificial intelligence for chemical risk assessment
Artificial intelligence/machine learning (AI/ML) models are New Approach Methodologies (NAMs) that have the potential to improve chemical risk assessment. Yet, trust in their predictions is lacking due to their perceived "black box" nature. RIVM researchers facilitated knowledge exchange between computational modellers and risk assessors using two AI/ML models: one on ecotoxicity and one on human toxicity. Results showed that trust, essential for regulatory acceptance, evolves over time and comprises technical and beyond-technical factors. The study underscores the importance of interdisciplinary collaboration for effectively integrating AI/ML models into regulation. Future activities should prioritise collaboration between modellers and assessors to optimize data and knowledge utilisation.
March 2024: Beyond Encapsulation: Exploring Macrophage-Fibroblast Crosstalk in Implant-Induced Fibrosis
Biomaterials are used to manufacture medical implants. Implantation is associated with a foreign body response, which may lead to implant failure. In this review, researchers from RIVM, TU Eindhoven and UMCG took a mechanism-based approach and proposed the use of Adverse Outcome Pathways to assess the causal link between material properties and the severity of the foreign body response. This approach can lead to more human-relevant and animal-free testing of biomaterials.
15 March 2024: Dutch National Growth Fund invests €124.5 million in transition to animal-free innovation
The Dutch National Growth Fund will invest 124.5 million euros in a new Centre for Animal-Free Biomedical Translation (CPBT) to accelerate the transition to animal-free research over the next decade. The centre aims to generate safer, more effective treatments while reducing animal suffering. RIVM, in collaboration with Utrecht University, UMC Utrecht and Utrecht University of Applied Sciences, is one of the initiators of the centre and is involved in strengthening the acceptance and use of animal-free biomedical innovations.
January 2024: Report of the First ONTOX Stakeholder Network Meeting: Digging Under the Surface of ONTOX Together With the Stakeholders
In March 2023, the first stakeholder meeting within the scope of the EU-funded project ONTOX was held. ONTOX stands for ontology-driven and artificial intelligence-based repeated dose toxicity testing of chemicals for next-generation risk assessment. The participants identified and discussed the drivers, barriers, and challenges of the implementation of new approach methodologies (NAMs) and probabilistic risk assessment with the ONTOX Hub platform as an example of an integrating platform. Specific topics, including hazard versus risk, the role of AI and machine learning, and regulatory requirements, were discussed in break-out groups.
Alternatives to Laboratory Animals 2024; online first January 18
November 2023: An integrated approach to testing and assessment (IATA) to support grouping and read-across of nanomaterials in aquatic systems
Many new materials are being developed, which have various nanoforms that can each have a different hazard profile potentially affecting the environment. It is challenging to test all these nanoforms, since this would require many tests to cover the range of hazard profiles. Some of these tests require experimentation with organisms like daphnia, worms and fish. In this paper by RIVM researchers and collaborators in the GRACIOUS project, an IATA to support grouping and read-across of nanomaterials in aquatic systems was developed. The tiered testing and grouping approach could lead to a reduction of the number of animal tests needed to assess the hazard profile of nanoforms.
November 2023: PhD defence: Identification of biomarkers of the retinoic acid signalling pathway in the zebrafish embryo model to predict human developmental toxicants
Laura Samrani of the RIVM, Utrecht University, and Université Paris-Saclay performed the research for this PhD thesis, which was funded by the CIFRE project. This thesis expands the understanding of developmental toxicity pathways by studying chemically induced gene expression changes related to the perturbation of the retinoic acid signalling pathway in a zebrafish embryo model. The optimal timing for studying the retinoic acid signalling pathway was found to be around 4 hours post-fertilisation. Exposure to teratogens revealed a number of potential gene biomarkers for developmental toxicity.
PhD thesis Laura Samrani. Utrecht University, 2023
November 2023: The importance of variations in in vitro dosimetry to support risk assessment of inhaled toxicants
Health effects of inhaled pollutants are determined by how low the pollutant is inhaled, how much we inhale and how often. Testing all these differences in animal studies is cumbersome, and the results may not reflect the impact on human health. In vitro models of the lung allow prediction of the health impact of many different exposure scenarios. RIVM researchers tested different models and exposure methods and listed criteria that can assist in experimental design and data interpretation. The authors recommend (i) determining what information is needed to plan the experiment, (ii) choosing an exposure method that is suitable for the pollutant of interest, (iii) determining the amount of pollutant that interacts with the lung (deposition), and (iv) considering the time between the exposure and measurement of the effect.
ALTEX, accepted manuscript, published October 12, 2023
November 2023: An adverse outcome pathway for chemical-induced Parkinson’s disease: Calcium is key
Exposure to pesticides is associated with an increased risk of developing Parkinson’ Disease later in life. Currently, rodent-based risk assessment studies cannot adequately capture neurodegenerative effects of pesticides. To improve risk assessment guidelines, a mechanism-based, human-relevant approach is needed. Researchers from RIVM and the Insitute of Risk Assessment Sciences (IRAS) of the Utrecht University developed an adverse outcome pathway (AOP) network for chemically induced Parkinson’s disease. This AOP can serve as the biological basis for this approach. Developing a testing strategy based on this AOP by combining in vitro and in silico systems, can facilitate hazard assessment of neurodegeneration, without the use of animals.
NeuroToxicology 2023: 99: 226-243
August 2023: Variability of in vivo potency assays of whole-cell pertussis, inactivated polio, and meningococcal B vaccines
For some vaccines, batch-release testing to determine potency or safety involves animal experiments. These in vivo potency assays show large inherent variability. In a study by CBG-MEB, Medicines and Healthcare Products Regulatory Agency (UK), Utrecht University and RIVM, this variability in the outcome of measurements of the potency of three vaccines was evaluated. Results showed, for example, that antibody responses to four meningococcal B antigens in >300 mice varied strongly and showed no correlation in individual mice. The large differences between individual animals likely contribute considerably to the inherent variability of in vivo potency assays. The low precision makes in vivo assays less suitable for monitoring manufacturing consistency and supports the notion of moving away from these assays for batch release testing.
Vaccine 2023; 41(38):5603-5613
August 2023: New approach methodologies in human regulatory toxicology – Not if, but how and when!
New Approach Methodologies (NAMs) have the potential to transform approaches to regulatory hazard and risk assessment fundamentally. Yet, major challenges need to be overcome for NAMs towards implementation into current legal frameworks. This manuscript describes a conceptual perspective that is grounded on the main findings and conclusions from a symposium held in Berlin in November 2021, at which RIVM was one of the experts. Experts address the need for developing a strategic framework for making legal frameworks “NAM-ready” step by step. Furthermore, they suggest the establishment of working groups to evaluate and re-describe regulatory testing requirements. A tentative timeline is presented to involve all relevant stakeholders in these activities and to make the transition to NAM-based risk assessment happen.
Environment Int 2023; 178:108082
August 2023: New approach methodologies to facilitate and improve the hazard assessment of non-genotoxic carcinogens—a PARC project
Non-genotoxic carcinogenic chemicals operate via various modes of action, thus requiring a suite of New Approach Methodologies (NAMs) for detecting this type of chemicals. RIVM is contributing to this integrative project that is performed within the context of the European Partnership for the Assessment of Risks from Chemicals (PARC). The aim is to identify suitable NAMs for the detection of carcinogenic potential of chemical substances. Ultimately, this work will contribute to an efficient and improved, internationally recognised hazard assessment of non-genotoxic carcinogens.
Front Toxicol 2023; 5
July 2023: Evaluation of non-clinical toxicity studies of COVID-19 vaccines
The safety of new vaccines is non-clinically tested in animal studies. Researchers from Leiden University and the Dutch Medicine Evaluation Board evaluated the outcomes of non-clinical toxicity studies of various SARS-CoV-2 vaccines. From a 3R perspective, they evaluated whether additional animal studies are needed or whether previous historical studies are already sufficient to inform the vaccine assessment process. The authors concluded that only product-specific safety studies, combined with a justified package of supportive historical studies that used the same product carrier, are considered sufficient to support clinical development. This reduces the number of animals required for nonclinical development of vaccines.
Regulatory Toxicology and Pharmacology 2023; 142:105438
July 2023: Retinoic acid signalling pathway perturbation impacts mesodermal-tissue development in the zebrafish embryo: Biomarker candidate identification using transcriptomics
In an effort to further optimize a NAM for developmental toxicity, RIVM researchers used a whole transcriptome approach to identify teratogenicity biomarker genes in the zebrafish embryo model. There were 248 genes regulated by the teratogens tested (all-trans retinoic acid and valproic acid), which were not regulated by the non-teratogenic compound (folic acid). A sub selection of the genes related to the retinoic acid pathway were identified as potential gene expression biomarkers of mesodermal tissue and organ malformation in early vertebrate embryos. To determine their robustness as biomarkers, these genes should be more broadly studied using different in vitro models and chemical exposures.
Reproductive Toxicology 2023: 119:108404
June 2023: Transferability and reproducibility of exposed air-liquid interface co-culture lung models
Lung models that can be exposed via the air, by means of an air-liquid interface, are promising in vitro models for evaluating the safety of chemicals and nanomaterials after inhalation exposure. Together with six other laboratories, RIVM researchers performed an interlaboratory comparison study to evaluate the transferability and reproducibility of a monoculture and coculture model. The lung models were exposed to nanomaterials at physiologically relevant dose levels. Interlaboratory variation for cell viability and barrier integrity were acceptable, whereas variation in production of inflammatory proteins was relatively high. The authors recommend further optimisation of the model and testing higher doses to improve reproducibility.
NanoImpact 2023; 31:100466
April 2023: An adverse outcome pathway network for chemically-induced oxidative stress leading to (non-)genotoxic carcinogenesis
Currently, carcinogenicity assessment of chemicals primarily relies on genotoxicity testing. Since non-genotoxic carcinogens do not induce direct DNA damage, these chemicals may remain undetected. To enhance the predictivity of carcinogenicity assessment testing strategies, a shift towards mechanism-based, human-relevant approaches is required. Researchers from RIVM and Leiden University have developed an adverse outcome pathway network for chemically-induced oxidative stress leading to carcinogenesis. This mechanism-based, human-relevant approach can aid in reducing the number of laboratory animals for carcinogenicity assessment.
Chem Res Toxicol 2023; online ahead of print
April 2023: Rational arguments for regulatory acceptance of consistency testing: benefits of non-animal testing over in vivo release testing of vaccines
Some vaccine batch release testing involves animal experiments that determine the potency or safety of the batch. In this perspective article, international regulatory bodies, including the CBG-MEB, call for the replacement of these animal tests by advanced in vitro methods, not only from an ethical perspective. They describe the hurdles and solutions to substitute in vivo assays and the advantages of in vitro methods, both as a superior monitoring tool for the quality of vaccines and as a more practical, economical, and ethical method. Government incentives and supportive regulatory authorities are deemed necessary to implement these novel animal-free tests.
Expert Review of Vaccines 2023; 22(1):369-77
April 2023: ZonMw TPI Knowledge Agenda for animal-free innovations in biomedical research
While the number of animal-free innovations that are being developed is increasing, they are not yet widely used in fundamental and translational biomedical science. ZonMw, the Dutch funding organisation of the programme “More Knowledge with Fewer Animals (Dutch acronym: MKMD) published the TPI Knowledge Agenda, in which they identify the obstacles, potential solutions and recommendations to stimulate the transition towards animal-free science (Dutch acronym: TPI). The TPI Knowledge Agenda is based on broad consultation of the biomedical research field in the Netherlands and written with the help of RIVM researchers. TPI Knowledge Agenda (news only in Dutch)
March 2023: PhD defence: Paving the road towards the Next Generation Risk Assessment - Quantitative in vitro to in vivo extrapolations for the pre-diction of human toxicity based on alternative testing
The research for this PhD thesis was performed by Stella Fragki of the RIVM and Utrecht University, and was funded by the European human biomonitoring project HBM4EU. Her thesis describes the extrapolation of concentration-response relations observed in in vitro assays to dose-response relations in human. For example, she showed that including data from a cell culture system mimicking the placental barrier improves extrapolation significantly. This approach, called quantitative in vitro to in vivo extrapolation (QIVIVE) is an important element in innovative hazard and risk assessment of chemicals and pharmaceuticals.
February 2023: 3Rs Working Party (3RsWP) plenary meeting - Public session on the 2023 work plan
Join the public session of the 3RsWP of the European Medicine Agency (EMA) on 28 February, 09:00–09:45. In this session the 3RsWP will present their work plan and priorities for 2023 and give an opportunity to stakeholders to comment and provide their views on the working party's activities. This public session is part of this newly established working party's two-day plenary meeting to showcase EMA's commitment to ensuring the implementation of 3Rs principles in the development and evaluation of human and veterinary medicinal products.
3Rs Working Party (3RsWP) plenary meeting
February 2023: Innovating human chemical hazard and risk assessment through a holistic approach
Regulatory toxicology has relied on animal studies as the gold standard for over half a century. It has increasingly been realised that the detour of the animal study for human risk assessment comes with drawbacks, both scientifically as well as ethically. In this publication, RIVM researchers pose that innovative New Approach Methodologies provide molecular and mechanistic data that can be integrated in computational models to predict adverse outcome at the level of the intact human. It is expected that in due course, current significant advances in computational toxicology and machine learning already effective in clinical practice, will be able to advance into a human-focused, animal-free risk assessment strategy. This strategy will be fine-tuned to the human situation and will therefore lack the scientific and ethical concerns of current classical regulatory animal testing for human chemical risk assessment.
Current Opinion in Toxicology 2023; available online 10 February 2023, 100386
February 2023: Prolonged differentiation of neuron-astrocyte co-cultures results in emergence of dopaminergic neurons
Epidemiological and experimental data suggest that pesticides affect dopaminergic cells in the brain. An effect that has been related to human neurodegenerative diseases such as Parkinson’s disease. To allow for human-relevant assessment of (developmental) neurotoxicity related to dopamine disruption, researchers from RIVM have developed a human stem cell-based differentiation protocol for dopaminergic neurons. Further characterisation and chemical testing are needed to define the role of the current model in a testing strategy to test how pesticides or other chemicals might affect the dopaminergic system.
Int J Mol Sci 2023; 24(4): 3608
February 2023: The State of the Art and Challenges of In Vitro Methods for Human Hazard Assessment of Nanomaterials in the Context of Safe-by-Design
The Safe-by-Design (SbD) concept aims to facilitate the development of safer materials/products throughout their life cycle. Early hazard screening is therefore essential. Partners of the SAbyNA consortium reviewed commonly used in vitro tests for their suitability for SbD hazard testing of nanomaterials. Some simple in vitro assays are capable of accurately predicting hazard warnings and hazard rankings for some but not all toxicological endpoints. The authors recommend that joint efforts of innovators, scientists, and regulators are needed to improve hazard testing for SbD approaches.
Nanomaterials 2023; 13(3): 472
January 2023: Smoking-associated exposure of human primary bronchial epithelial cells to aldehydes: impact on molecular mechanisms controlling mitochondrial content and function
Respiratory toxic aldehydes are generated during smoking of tobacco. To study the role of aldehydes on the molecular regulation of mitochondrial content/function, Maastricht University and RIVM used a differentiated in vitro model of human primary bronchial epithelial cells exposed to cigarette smoke following a realistic exposure protocol. Cigarette smoke caused disruption of molecular mechanisms controlling mitochondrial content and quality. However, exposure to a mixture of three aldehydes only caused a dysregulation of markers associated with autophagy and mitophagy. This suggests that other compounds then aldehydes contribute to cigarette smoke-induced dysregulation of mitochondrial content/function.
Cells 2022; 11(21): 3481
January 2023: Re-evaluating the need for chronic toxicity studies with therapeutic monoclonal antibodies, using a weight of evidence approach
For the registration of monoclonal antibodies (mAbs) for chronic indications, 6-month as well as 3-month toxicity studies in rodents are conducted. However, experience has shown that mAbs are generally well tolerated, thereby questioning the relevance to assess human safety in long term rodent toxicity studies. Researchers of the CBG-MEB studied whether a 3-month study is already sufficient to assess the long-term safety of mAbs. For the majority of the 111 assessed mAbs novel toxicity is rarely detected in animal studies of longer than 3 months. This may allow for a case-by-case approach to reduce animal use by conducting a 3- instead of 6-month study.
Regul Toxicol Pharmacol 2023; 138:105329
January 2023: The use of recovery animals in nonclinical safety assessment studies with monoclonal antibodies: further 3Rs opportunities remain
When performing nonclinical safety testing of a monoclonal antibody (mAb) in animals, it is sometimes required to include a recovery group. According to the guidelines, this is only needed in one of the nonclinical studies. A working group, including participants from CBG-MEB, reviewed 51 mAb toxicity studies and found that often recovery groups are included in multiple nonclinical studies over the course of testing a mAb. The working group concluded that by limiting inclusion of a recovery group to a single nonclinical toxicology study provides opportunities to decrease animal use for this drug class. Regul Toxicol Pharmacol 2023; 138:105339
December 2022: Towards achieving a modern science-based paradigm for agrochemical carcinogenicity assessment
The rodent cancer bioassay has been the standard approach to test chemicals for human carcinogenic potential. However, there are known limitations to this assay, leading to a search for more human-relevant approaches providing mechanistic information on chemical carcinogenesis. In this paper the authors outlined the challenges and opportunities that authorities should consider when building a roadmap that should lead to global acceptance and incorporation of fit-for-purpose new approaches for carcinogenicity assessment of agrochemicals. New approaches include shorter-term tests, including in vitro and in silico approaches. To the publication.
December 2022: Application of AOPs to assist regulatory assessment of chemical risks – Case studies, needs and recommendations
The Adverse Outcome Pathway (AOP) framework is an important tool in moving towards next generation risk assessment (NGRA). A workshop organised within the European Union partnerships HBM4EU and PARC was held to address issues related to using AOPs in a regulatory context. AOPs have shown useful in e.g. hazard characterisation and in identification and validation of biomarkers of effect. However, e.g. lack of quantitative information on response-response relationships holds AOP application back. The paper discusses suggestions, initiatives and tools that may help to better implement AOPs in the NGRA. To the publication.
December 2022: Neurodegeneration in a Regulatory Context: The Need for Speed
There is increasing evidence that pesticides can induce or accelerate neurodegenerative diseases. Current regulatory guidelines for safety assessment cannot fully capture the neurodegenerative effects of chemical substances. In this publication, researchers from RIVM propose a tiered approach to update the regulatory guidelines. In the short term, adaptations to current guideline studies can be made. In the long term transition of chemical safety assessment to a strategy based on human biology using in vitro and in silico methods should be adopted. To the publication.
December 2022: Applicability of generic PBK modelling in chemical hazard assessment: A case study with IndusChemFate
Various physiologically based kinetic (PBK) models exist that may all vary in their chemical applicability domain. In this study, the generic physiologically based kinetic model IndusChemFate was evaluated and compared to the PBK “TNO Model”. Both models were evaluated with a broad span of chemicals varying in physicochemical properties. Results showed that the simpler IndusChemFate model performed better as a first tier for simulating toxicokinetics based on QSARs and in vitro parameters. Findings were illustrated in HepaRG cells exposed to acetaminophen. To the publication.
December 2022: Dynamic regulation of gene expression and morphogenesis in the zebrafish embryo test after exposure to all-trans retinoic acid
This publication evaluated the Zebrafish Embryo Test (ZET) for the prediction of developmental toxicity. The effect of exposure duration of all-trans retinoic acid on the magnitude of gene expression changes was investigated. Results showed that gene expression regulation indicative of developmental toxicity could be observed already at early time points after exposure. Considering early time point measurements of gene expression changes could help optimise the sensitivity of the ZET in future studies. To the publication.
18 November 2022: Hugo van Poelgeest Award won by Niels Harlaar
The Hugo van Poelgeest Award is a scientific prize for excellent, animal-free research in the life sciences. Niels Harlaar (LUMC) won the award for his research on transformed human heart cells. Valentina Palacio-Castañeda (Radboudumc) won the audience award, and Victoria de Leeuw (RIVM) was nominated. The prize is awarded every other year by stichting Proefdiervrij and stichting Bouwstenen voor Dierenwelzijn. Read more (in Dutch).
November 2022: The Current Status and Work of Three Rs Centres and Platforms in Europe
Over recent years, an increasing number of 3R centres and platforms have been established in Europe. Together with representatives of European 3R initiatives, RIVM contributed to a publication that provides an overview of the current activities of the 3R centres: the financial and organisational structures of the, what their Three Rs focus and core activities are (dissemination, education, implementation, scientific quality/translatability, ethics), and their areas of responsibility and projects. See the publication.
22 October 2022: Analyses of Transcriptomics Cell Signalling for Pre-Screening Applications in the Integrated Approach for Testing and Assessment of Non-Genotoxic Carcinogens
Mechanistic understanding of biological processes that lead to carcinogenesis is expanding. Transcriptomics can inform on non-genotoxic mechanisms of cancer caused by chemicals. An OECD working group, in which RIVM participates, reviewed the application of transcriptomics for regulatory applications. Specifically, they evaluated the potential of gene expression analyses to identify the most relevant approaches that could be utilised as (pre-)screening tools. Challenges related to the integration of gene panels and transcriptomic assays into an Integrated Approach to the Testing and Assessment of non-genotoxic carcinogens is also discussed. To the publication.
11 October 2022: Renewal of the EURL ECVAM Scientific Advisory Committee (ESAC) and open call for application subgroups
The Joint Research Centre (JRC) formally appointed nine experts as the new member of the ESAC on 11 October 2022. Anne Kienhuis, senior scientist of the RIVM is one of the new members. ESAC provides EURL ECVAM with independent scientific advice on the adequacy and outcome of formal validation studies carried out to assess the reliability and relevance of NAMs in the context of regulatory safety assessment. Read more in this news item.
New videos on TPI.tv
Working towards animal-free research strategies is an effort crossing international and interdisciplinary borders. TPI.tv is designed to facilitate this transition through connecting people and ideas via video messages. On TPI.tv, short video messages (‘pitches’) provide the medium for researchers to display their findings and request input if needed. New videos on TPI.tv:
In3 | Helpathon #6 | Helpathon #7 | In vitro atrial fibrillation | In vitro neurodevelopmental toxicity assessment | Tumour-on-chip
October 2022: 3Rs concepts to improve the quality of biomedical science COST-Action IMPROVE
Improving the quality of biomedical science by using 3Rs concepts is the main aim of the new COST-Action IMPROVE. In this initiative, a network of researchers will be established to refine, harmonise and promote 3Rs concepts, data and documents, in order to improve the quality of biomedical science. Researchers interested in contributing can apply for working groups on the (1) Quality and Translatability of Science, (2) Implementation, (3) Dissemination, and (4) Education. The consortium is co-led by Utrecht University and RIVM and is funded by the Dutch National Research Agenda. Read more about IMPROVE.
September 2022: Prioritisation of chemicals in food for risk assessment by integrating exposure estimates and new approach methodologies: A next generation risk assessment case study
Next generation risk assessment (NGRA) is a knowledge-driven system that allows for cost-efficient, animal-free chemical risk assessment. In this case study, researchers at RIVM showed how NGRA can facilitate prioritisation of chemical substances in food. They explored how exposure data combined with the Threshold of Toxicological Concern concept could be used to prioritise chemicals for toxicity testing. A selected set of compounds from this analysis was screened for toxicological potential using high-throughput screening. This study is a proof-of-principle that this approach can be a supportive element in NGRA. To the publication.
September 2022: Development of a cell line-based in vitro assay for assessment of Diphtheria, Tetanus and acellular Pertussis (DTaP)-induced inflammasome activation
Safety and potency assessment for batch-release testing of established vaccines still partly relies on animal tests. As part of the VAC2VAC project, researchers at RIVM developed an in vitro testing method for adjuvant biological activity that can contribute to animal-free potency testing of vaccines. Specifically, they developed an NLRP3 inflammasome activation test for aluminium-adjuvanted vaccines (the DTaP vaccine). The results indicated that inflammasome activation may be used to measure adjuvant biological activity as an important quality attribute for control or characterisation of the adjuvant. More information in the publication Development of a cell line-based in vitro assay for assessment of Diphtheria, Tetanus and acellular Pertussis (DTaP)-induced inflammasome activation.
September 2022: Realistic in vitro exposure of neuronal cells to e-cigarette vapour
Chemical exposure through the airways may affect the airways themselves, but can also cause secondary effects on, for example the brain. Researchers at RIVM and Utrecht University studied an in vitro approach to test the effects of e-cigarette vapour, using a combination of a lung cell model and a neuronal cell model. Components of the e-cigarette vapour could cross the lung cell barrier and subsequent exposure on the neurons modulated their spontaneous electrical activity. This approach, when optimised, can improve realistic exposure in vitro, decreasing the need for animal studies. Read more Neuromodulatory and neurotoxic effects of e-cigarette vapor using a realistic exposure method.
August 2022: Biomarkers for quality control of Weil’s disease vaccines
Potency testing of Leptospira (Weil's disease) vaccine batches relies partially on laboratory animals. Cell-based assays could replace in vivo tests for vaccine quality control if biomarkers indicative of Leptospira vaccine potency are identified. RIVM contributed to a study that used a canine monocyte/macrophage cell line to investigate innate immune responsiveness by Leptospira species as well as Leptospira vaccines from two different manufacturers. Gene and protein expression analysis led to the identification of four proteins for the development of biomarker-based assays. Read more Transcriptome and proteome analysis of innate immune responses to inactivated Leptospira and bivalent Leptospira vaccines in canine 030-D cells.
August 2022: Animal-free assays for endocrine disruption – from science to regulatory acceptance
Researchers from, amongst others, Utrecht University and RIVM will assess how to improve the regulatory acceptance and use of animal-free assays for endocrine disruption. The consortium receives funding worth 1 million euros from the Dutch Research Agenda for this purpose. The ultimate aim of the project is to achieve regulatory and societal acceptance towards the implementation of existing animal-free assays for endocrine disruption in regulatory frameworks. In this project, a multi-disciplinary consortium with experts in toxicology, social sciences and legislation will combine their efforts to investigate and accelerate the transition towards the use of animal-free assays for endocrine disruption. Read more (in Dutch).
July 2022: Identification of proteome markers for drug-induced liver injury in zebrafish embryos
The zebrafish embryo is a promising alternative non-rodent model in toxicology. Scientists at RIVM and Leiden University exposed zebrafish embryos to nine hepatotoxicants (targeted at induction of steatosis, cholestasis and necrosis). Next, they determined protein expression changes using LC-MS/MS and identified differentially expressed proteins and pathways. Overlap between these responses resulted in a set of ten common protein markers for the detection of adverse liver responses. This may allow for a reduction in rodent use for hepatotoxicity assessment. Read more Identification of proteome markers for drug-induced liver injury in zebrafish embryos.
June 2022: Roadmap for Action on New Approach Methodologies in Risk Assessment
The European Food Safety Authority set out a call to develop a roadmap for the implementation of New Approach Methodologies (NAMs) in food risk assessment. A team of experts, from Fraunhofer ITEM, RIVM, Vrije Universiteit Amsterdam, Technical University of Denmark, and EURA AG defined key barriers and opportunities as well as activity proposals for implementation of NAMs in food risk assessment in seven areas: development of additional adverse outcome pathways (AOPs)/AOP networks, advanced cell culture models including organ-on-chip, toxicokinetic assessment with a focus on physiological based kinetic modelling, use of exposome data, integration of human susceptibility, data integration and new concepts in human risk assessment for NAM implementation. Furthermore, a Forum is proposed to facilitate interaction between stakeholders for the implementation of NAMs in risk assessment. Read more.
May 2022: Update Landscape NAMs
We have published an update of the Landscape NAMs for the safety assessment of chemical substances. The overview provides information on each step in the implementation curve. With this Landscape, we facilitate the uptake of NAMs in regulatory safety testing. Go to the Landscape NAMs.