fosterceller

Fosterceller, often translated as feeder cells, are a type of cultured cells used to support the growth and maintenance of another cell population. They form a semi-rigid layer on the culture substrate and provide both a physical surface and a source of signaling factors that help target cells survive, attach, and, in some cases, remain undifferentiated. The term is commonly used in stem cell biology, where pluripotent cells such as embryonic stem cells (ES cells) or induced pluripotent stem cells (iPS cells) are nurtured on a bed of fosterceller.

Preparation and use: Fosterceller are typically prepared as a confluent layer and then inactivated so they cannot divide. Inactivation is usually achieved by irradiation or treatment with mitomycin C. After inactivation, the target cells are plated on top and grown under conditions that favor proliferation while preserving their stem-like properties.

Common types: Historically, mouse embryonic fibroblasts (MEFs) have been a standard fosterceller for human and mouse ES cells. Human feeder cells, such as human foreskin fibroblasts, have also been used, as have specialized cell lines such as STO or other fibroblast-derived layers. The choice of feeder cells can influence the signaling environment and the efficiency of maintaining pluripotency.

Limitations and evolution: The use of fosterceller introduces variables including species-specific factors and batch-to-batch variability, and may pose risks for clinical-grade cell production due to potential xeno-contamination. As defined, feeder-free, chemically defined culture systems have been developed and increasingly adopted, though fosterceller remain relevant in some research contexts and for certain cell lines.

See also: feeder layer, stem cell culture, pluripotency.