• Methods of original research papers must use both cells and matrix materials

• Papers featuring cells cultured on typical flat surfaces (e.g. historic 2D cell culture)
• Papers featuring only a proposed new scaffold material / no use with cells

• Such papers do not feature cells cultured in 3D
• Such papers do not utilize cell culture

*Exception to above: Techniques which demonstrably generate matrix in situ; e.g. pellet or rotary methods

* The lack of matrix is a temporal technicality; it has been shown that these techniques result in the formation of matrix materials over time

• Methods of original research papers must utilize in vitro techniques

• Papers featuring only in vivo implantation of construct designed to attract cells from surrounding tissue

• Such papers do not utilize cell culture

• Methods of original research papers must utilize in vitro analysis or characterization of cell/matrix construct

• Papers featuring cell seeded but unanalyzed cell/matrix constructs later implanted in vivo

• Such papers do not provide any information about cell culture; i.e. it is a means but not an end

• Review papers describing a topic expressly targeted towards 3D cell culture or tissue engineering, even those which may feature only a cell focus or only a material type

• Other review papers lacking a 3D cell culture or tissue engineering focus

• Such reviews do not provide information about cell culture

• Papers must feature eukaryotic cells

• Papers featuring bacterial cultures

• Lack of relevance to website focus

• Papers must feature cells having mammalian or avian origin

• Papers featuring plant, mollusk, insects, spiders, fish or amphibian cells

• Lack of relevance to website focus

• Matrix or scaffold material must have a minimum thickness of 50 µm (micrometers) within which cells can be situated

• Papers featuring typical surface coatings or films

• Assuming an average minimum cell dimension of 10 µm (micrometers), very few if any cells in such papers are in a 3D environment

*Exception to above: Surfaces which demonstrably induce spheroid or aggregate formation of cultured cells

• Cells in aggregates or spheroids are in a 3D environment; see in situ matrix generation exception above

• Must be peer-reviewed

• Conference abstracts or proceedings

• Typically such short papers lack detail on materials and methods and cannot be independently replicated

• Citation and abstract must be available in English language

• Citations not available in English

• Inability to characterize or utilize content due to language limitations of both web site staff and majority audience