新しいアプローチ手法（NAMs）の紹介

New Approach Methodologies (NAMs) are modern scientific strategies that generate biological data while reducing reliance on traditional vertebrate animal models. NAMs include computational modeling, cell-based assays, organ-on-chip systems, and alternative animal models like zebrafish embryos. These approaches support the 3Rs principle—Replacement, Reduction, and Refinement—enabling researchers to conduct ethical, efficient studies with human-derived cells and tissues.

Computational methods analyze test compound structures, identify relevant target proteins, and evaluate compound-protein interactions to predict potential biological effects. These approaches help prioritize compounds for further testing before moving to laboratory studies. By identifying promising candidates early, computational modeling reduces the number of compounds requiring experimental evaluation and supports more efficient research planning.

Cell-based assays are non-animal methods used to evaluate compound effects under controlled in vitro conditions. Cells can be treated with test compounds to assess cytotoxicity, and different concentrations can be tested to determine effective doses before progressing to animal models. These assays provide mechanistic and toxicity-related information while reducing the need for vertebrate animal studies.

Alternative animal models such as zebrafish embryos and Drosophila (fruit flies) are used to refine compound selection and evaluate toxicity effects. For example, zebrafish embryo development can be assessed to determine compound safety before testing in traditional vertebrate models. These alternatives provide valuable biological data while supporting the principles of Replacement and Reduction in research.

Organ-on-chip systems are advanced in vitro technologies that mimic organ function in controlled laboratory environments. These systems allow researchers to study biological processes and evaluate compound effects with greater physiological relevance than traditional cell cultures. By providing realistic tissue responses, organ-on-chip systems reduce the need for animal testing while generating high-quality biological data.

Integrating data from computational methods, cell-based assays, organ-on-chip systems, and alternative animal models creates a comprehensive evaluation strategy. Computational methods prioritize compounds, in vitro systems provide mechanistic data, and alternative models offer additional safety assessment. This integrated approach identifies promising compounds and potential hazards early, improving study design, reducing animal use, and supporting more efficient research.

NAMs are designed to support the 3Rs principle: Replacement (using non-animal methods), Reduction (minimizing animal numbers), and Refinement (improving animal welfare). All animal procedures must comply with institutional ethics guidelines and IACUC approval. By using human-derived cells and tissues and identifying safety concerns early, NAMs help researchers conduct ethical studies that reduce vertebrate animal reliance while maintaining scientific rigor.