Altex-Alternatives To Animal Experimentation最新文献

The Virtual Human Platform for Safety Assessment (VHP4Safety) project aims to build a virtual human platform (VHP) to protect human health and revolutionize the safety assessment of chemicals and pharmaceuticals by transitioning from animal-based to human-based approaches. The goal of this article is to introduce the project and its interdisciplinary approach to co-creation with mul­tiple academic, regulatory, industrial and societal partners covering the entire safety assessment knowledge chain. Three research lines drive the project: 1) building the VHP; 2) feeding the VHP with human data; and 3) implementing the VHP. The project focusses on three case studies that incor­porate human-relevant scenarios not included in current animal-based safety assessment strategies. The VHP is built on tools and services, including pharmacokinetic and computational models, and integrates several data sources within each case study, including data on human physiology, epi­demiology, toxicokinetic and -dynamic parameters, as well as data on chemical characteristics and exposures. In addition, the VHP integrates new data generated within the project using new approach methodologies representing key events within adverse outcome pathways. Implemen­tation of the VHP is investigated using an innovation systems approach, engaging stakeholders, and organizing training and education. Central to the VHP4Safety project is our co-creative approach, which is facilitated by biannual designathons and hackathons that foster active involvement of all project participants from over 30 partner organizations. By integrating technological innovations with transparency and stakeholder collaboration, the VHP4Safety project will help shape the tran­sition to next generation safety assessment in which animal testing becomes redundant.

Surfactants and film-forming polymers are common ingredients in consumer spray products such as cleaning products, hair care products, and anti-perspirants. Spraying eases application by creating aerosolized droplets of the product that can distribute evenly over the treated surface. However, these aerosols can potentially be inhaled during their normal application. Droplets that reach the alveoli can interact with the pulmonary surfactant, a complex mixture of phospholipids and proteins that regulates the surface tension at the air-liquid interface. This interaction can elevate the minimum surface tension at maximum compression and change the surface rheology of the pulmonary sur­factant at the interface. We tested four surfactants and seven polymers for their ability to inhibit pulmonary surfactant function in vitro and investigated if the inhibition is dose rate-dependent, i.e., the product of the concentration (mg/mL) and aerosolization rate (mL/min). We found a clear dose rate-dependent inhibition of pulmonary surfactant function independent of chemical class (surfactant or polymer) and that different chemicals inhibited function at different dose rates. We compared the points of departure of inhibitory chemicals to that of a polymer with known dose rate-dependent lung toxicity. When assessing the risk of chemicals that might be inhaled, it is essential to ensure normal use would not inhibit pulmonary surfactant function leading to immediate effects on the lungs.

Potency and quantitative risk assessment are essential for determining safe concentrations for the for­mulation of potential skin sensitizers into consumer products. Several new approach methodologies (NAMs) for skin sensitization hazard assessment have been adopted in OECD test guidelines. Work is ongoing to develop NAMs for predicting skin sensitization potency on a quantitative scale for use as a point of departure in next generation risk assessment (NGRA). GARDskin Dose-Response (DR) is an adaptation of the GARDskin assay (OECD TG 442E); its readout is a quantitative potency pre­diction similar to the No Expected Sensitization Induction Level (NESIL) value (μg/cm2). Our goal was to evaluate the performance of the GARDskin DR for potency prediction of fragrance ingre­dients. One hundred fragrance ingredients from a reference database were tested in GARDskin DR. Materials tested had various protein-binding reactivity alerts, including Schiff base, Michael addition, SN2, and acylation. Potency categories were predicted with a total accuracy of 37% and an approximate accuracy (exact match or off by one category) of 81%. Combining predicted weak and very weak categories increased total accuracy to 53% and approximate accuracy to 98%. The mean prediction error for the NESIL and local lymph node assay (LLNA) EC3 was 3.15-fold and 3.36-fold, respectively. Based on the results of this study, GARDskin DR is a promising pre­dictor of skin sensitization potency with an applicability domain covering a wide range of fragrance ingredient reaction mechanisms, increasing the confidence in using the assay to conduct NGRA, ultimately reducing the need for animal testing.

Performance of pharmacokinetic models developed using in-vitro-to-in-vivo extrapolation (IVIVE) methods may be improved by refining assumptions regarding fraction absorbed (Fabs) through the intestine, a component of oral bioavailability (Fbio). Although in vivo measures of Fabs are often unavailable for non-pharmaceuticals, in vitro measures of apparent permeability (Papp) using the Caco-2 cell line have been highly correlated with Fabs. We measured bidirectional Papp for over 400 non-pharmaceutical chemicals using the Caco-2 assay. A random forest quantitative structure-property relationship (QSPR) model was developed using these and peer-reviewed pharmaceutical data. Both Caco-2 data (R2 = 0.37) and the QSPR model (R2 = 0.29) were better at predicting human bioavailability compared to in vivo rat data (R2 = 0.23). After incorporation into a high-throughput toxicokinetics (HTTK) framework for IVIVE, the Caco-2 data were used to estimate in vivo administered equivalent dose (AED) for bioactivity assessed in vitro. The HTTK-predicted plasma steady state concentrations (Css) for IVIVE were revised, with modest changes predicted for poorly absorbed chemicals. Experimental data were evaluated for sources of measurement uncertainty, which were then accounted for using the Monte Carlo method. Revised AEDs were subsequently compared with exposure estimates to evaluate effects on bioactivity:exposure ratios, a surrogate for risk. Only minor changes in the margin between chemical exposure and predicted bioactive doses were observed due to the preponderance of highly absorbed chemicals.

An essential aspect of the EU’s Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulation is the European Chemicals Agency’s (ECHA) evaluation of testing proposals submitted by registrants to address data gaps. Registrants may propose adaptations, such as read-across, to waive standard testing; however, it is widely believed that ECHA often finds justifications for read-across hypotheses inadequate. From 2008 to August 2023, 2,630 testing proposals were submitted to ECHA; of these, 1,538 had published decisions that were systematically evaluated in this study. Each document was manually reviewed and information extracted for further analyses, focusing on 17 assessment elements (AEs) from the Read-Across Assessment Framework (RAAF) and testing proposal evaluations (TPE). Each submission was classified as to the AEs relied upon by the registrants and by ECHA. Data was analyzed for patterns and associations. Adaptations were included in 23% (350) of proposals, with analogue (168) and group (136) read-across being most common. Of the 304 read-across hypotheses, 49% were accepted, with group read-across showing significantly higher odds of acceptance. Data analysis examined factors such as tonnage band (Annex), test guidelines, hypothesis AEs, and structural similarities of target and source sub­stances. While decisions were often context-specific, several significant associations influencing acceptance emerged. Overall, this analysis provides a comprehensive overview of 15 years of experience with testing proposal-specific read-across adaptations by both registrants and ECHA. These data will inform future submissions as they identify most critical AEs to increase the odds of read-across acceptance.

Microphysiological systems (MPS) are designed to recapitulate aspects of tissue/organ physiology in vivo, thereby providing potential value in safety and efficacy assessments of FDA-regulated products and regulatory decision-making. While there have been significant advances in the development, use, and proposals of qualification criteria for human organ MPS, there remains a gap in the development using animal tissues. Animal MPS may be of value in many areas including the study of zoonotic diseases, assessment of the safety and efficacy of animal therapeutics, and possibly reduction of the use of animals in regulatory submissions for animal therapeutics. In addition, the development of MPS from various animal species enables comparison to animal in vivo data. This comparison, while not always critical for all contexts of use, could help gain confidence in the use and application of human MPS data for regulatory decision-making and for the potential identification of species-specific effects. The use of animal MPS is consistent with the replacement, reduction, and refinement (3Rs) principles of animal use by identifying toxic compounds before conducting in vivo studies and identifying the appropriate species for testing.

Few of the many chemicals that regulatory agencies are charged with assessing for risk have been carefully tested for developmental neurotoxicity (DNT). To speed up assessment, and to reduce the use of vertebrate animals, great effort is being devoted to alternative laboratory models for DNT. A major DNT mechanism is altered neuronal architecture resulting from chemical exposure during neurodevelopment. Caenorhabditis elegans is a nematode that has been extensively studied by neurobiologists and developmental biologists, and to a lesser extent by neurotoxicologists. The development of the nervous system in C. elegans is easily visualized, entirely invariant, and fully mapped. We hypothesized that C. elegans could be a powerful in vivo model to test chemicals for their potential to alter neuronal architecture during development. We developed a novel C. elegans DNT testing paradigm that includes developmental exposure, examines major neurotransmitter neuronal types for architectural alterations, and tests neuron-specific behaviors. We characterized the effects of exposures to the developmental neurotoxicants lead, cadmium, and benzo(a)pyrene on neuronal architecture and specification. We identified no cases in which the apparent neurotransmitter type of the neurons we examined changed, but many in which neuronal morphology was altered. We found that neuron-specific behaviors were altered during C. elegans mid-adulthood for populations with measured morphological neurodegeneration in earlier stages. The functional changes were consistent with the morphological changes in terms of the type of neuron affected. Finally, we identified changes consistent with those reported in the mammalian DNT literature, strengthening the case for C. elegans as a DNT model.

Microphysiological systems (MPS), including organ-on-chip platforms and complex organoid models, represent a transformative approach to human-relevant in vitro modeling. These technol-ogies bioengineer aspects of organ architecture and functionality, revolutionizing drug development, reducing animal testing, and enabling personalized medicine approaches. Despite significant advances, several critical challenges remain before their full potential can be realized. This article examines key obstacles facing MPS adoption and implementation while proposing actionable solu-tions to accelerate their development and acceptance. Major challenges include standardization issues across terminology and protocols, validation complexities requiring robust reference com-pounds and benchmarking standards, regulatory uncertainties regarding data requirements and qualification processes, and barriers to effective data sharing among stakeholders. The paper traces the field's evolution through various international initiatives, particularly highlighting the Center for Alternatives to Animal Testing's (CAAT) contributions, including the establishment of the International MPS Society and World Summits. Proposed solutions emphasize establishing global standards through international consortia, enhancing validation frameworks through specialized validation centers, fostering collaboration through pre-competitive consortia and standardized data formats, and advancing regulatory integration through detailed case studies and clear guidance documents. Future priorities focus on overcoming technical challenges in biological complexity, addressing engineering hurdles, standardizing technologies, improving data management, increasing eco-nomic accessibility, and integrating with other emerging technologies. The path forward requires coordinated, collaborative efforts across academia, industry, regulatory agencies, and technology suppliers to systematically address these interrelated challenges.