From Primary Culture to Vaccine Development: The Diverse Roles of Fetal Bovine Serum in Animal Experiments

Establishing a stable cell model depends on suitable culture conditions.

In animal experiments, many studies require first culturing cell models in vitro, for example, using cells derived from mice, rats, or pigs for drug screening, toxicity evaluation, or mechanistic research. Fetal bovine serum is often used as a medium supplement to help these cells survive and proliferate better in vitro. Completely serum-free systems without animal serum support are sometimes unable to establish stable culture conditions within a short period, especially for cells that have just been revived or are in a weak state.

Primary cell culture: more dependent on natural support

Primary cells are isolated directly from animal tissues. Unlike commercial cell lines, they are more sensitive to environmental changes. Suitable fetal bovine serum can provide attachment factors, growth factors, and antioxidant substances to help primary cells get through the fragile stage after isolation. Primary cells from different animal species and tissue sources may have different requirements for serum lot and concentration. Researchers often need to first perform small-scale screening to find conditions suitable for the current primary cells.

The "confidence" of vaccine development and immunological research

In research related to vaccine production, cell culture is an important step for amplifying viruses or expressing antigens. Fetal bovine serum can support the growth of a variety of mammalian cells, so it is often used to culture common production cells such as Vero cells and BHK cells. In immunological experiments, fetal bovine serum is also used when culturing macrophages, lymphocytes, or dendritic cells, but endotoxin levels must be noted because immune cells are relatively sensitive to trace stimulation.

Stem cell research: higher requirements for serum quality

Stem cell culture is usually more demanding regarding indicators such as serum lot, concentration, and endotoxin. Some stem cell experiments use low-concentration serum or screened specialized serum to maintain an undifferentiated state or induce directed differentiation. Researchers evaluate whether serum is suitable based on cell morphology, marker expression, and differentiation capacity. In recent years, serum-free or chemically defined media have become increasingly common, but in many basic research and animal experiment-related cultures, fetal bovine serum is still an important transitional or supplementary choice.

Overall, fetal bovine serum plays an important role in supporting cell growth among bioreagents for animal experiments. In the future, with the development of alternative technologies, its use will become more refined, but understanding its value and limitations remains a fundamental skill for researchers.