celldependent

Celldependent is an adjective used in biology to describe a process, effect, or requirement that depends on living cells. In general, a cell-dependent phenomenon cannot occur in completely cell-free conditions.

The term is used across subfields: in microbiology and parasitology to describe organisms or processes that require host cells to reproduce or function (for example, obligate intracellular parasites such as Rickettsia). In immunology, cell-dependent responses rely on interactions between immune cells and their targets. In pharmacology and toxicology, many assays are described as cell-dependent because they require viable cells to observe effects of compounds.

In research design, labeling results as cell-dependent signals that the observed activity may not translate to non-cellular systems. The opposite is cell-free. The hyphenation varies; cell-dependent is common, but celldependent also appears in some databases or product names.

See also: cell-free, intracellular, cell culture, cytotoxicity assay, host-pathogen interaction.