Table 1.

	Monoculture	Nonscaffolded coculture	Organotypic coculture
Composition	Simple	Moderate, multicellular	Complex 3D, multicellular
Interactivity	Direct response to stimulus	Synergistic/antagonistic/intercellular	Synergistic/antagonistic/intercellul- ar/stratified
In vivo likeness	Least similar	Moderately similar	Best model of in vivo
Technical requirements	Simple culture and media components	Distinct media needs, no scaffolding requirements	Extensive expertise in media, culture and perfusion
Contamination	Low risk	Moderate risk with continuous cell lines	Moderate risk with continuous cell lines
Architecture considerations	Monolayer or suspension	Mixed monolayer, suspension, or combination	Scaffolds, gels, permeable barriers, media perfusion