01748nas a2200229   4500000000100000000000100001008004100002260001500043653001700058653003000075653003100105653002900136653002600165653002100191100001700212700002100229245011800250856009200368490000600460520103800466022001401504       2026                            d  c2026-03-1010acell culture10afoetal bovine serum (FBS)10ahuman-derived alternatives10aplant-based alternatives10aregulatory challenges10aserum-free media1 aHuiyuan Meng1 aPhilip J. R. Day00aExploring ethical, sustainable and effective foetal bovine serum alternatives for in vitro mammalian cell culture  uhttps://www.frontiersin.org/journals/toxicology/articles/10.3389/ftox.2026.1776815/full0 v83 aFoetal bovine serum (FBS) has been widely used as a nutrient-rich supplement in mammalian cell culture for over 6 decades; however, its usage has increasingly raised various concerns and challenges related to quality variations, unethical collection practices, supply-demand imbalance and regulatory challenges. In recent years, alternatives have been investigated to reduce or replace FBS in mammalian cell culture. Starting from a comprehensive analysis of components of FBS and their functions in cell growth, this review compares the main types of FBS alternatives, i.e., human and animal-derived, plant-based alternatives and serum free media. Future perspectives discussed include the development of application-specific FBS alternatives, improvements in the quality and specialized formulation of FBS, optimization of existing alternatives and the establishment of databases and incentive mechanisms to facilitate the transition away from FBS. Lastly, the guidance for selecting appropriate FBS alternatives is also discussed.  a2673-3080