Isolation and Culture of White and Brown Preadipocytes from Mouse Embryos

Adipose tissue plays a central role in metabolic homeostasis, and its properties are shaped during embryonic development through adipocyte differentiation. Embryonic preadipocytes, therefore, represent a relevant model to study early events in adipose tissue formation and lineage specification. This article describes a reproducible protocol for the isolation and in vitro differentiation of white and brown preadipocytes isolated from mouse embryos at embryonic day 15.5 (E15.5), a developmental stage at which adipose depots begin to form. The method provides detailed guidance for tissue microdissection, enzymatic digestion, primary culture, and lineage-specific differentiation conditions that support cell viability and adipogenic maturation. Representative results include lipid droplet accumulation and lineage-associated marker expression, confirming successful differentiation under defined culture conditions. Using this approach, embryonic preadipocytes can be directed toward white or brown adipocyte fates, enabling comparative analyses of developmental timing, lineage characteristics, and gene expression profiles. This protocol offers a practical and developmentally relevant tool for investigating adipose tissue formation and perinatal programming mechanisms in a controlled experimental setting.