3D Cell Culture
In the human body, cells assume a generally round, three dimensional (3D)shape. In traditional 2D cell culturing, cells are grown in a flat, plastic dish. The cells adhere and spread on the synthetic surface forming a single monolayer. In a monolayer of cells, the cells are flat, stretched and under stress. They are limited in cell-cell and cell-matrix interactions so they begin to form unnatural cell attachments. This contributes to poor survival of normal cells and prevents us from modeling higher order cell processes, such as tumor invasion and metastasis, that are inherently 3D. In their unnatural 2D state, cellular gene and protein expression are altered which results in artificial changes to cell structure, function, signaling, and responses to drugs.Today, many drugs are also designed to target specific receptors on the cell surface (targeted therapies). The expression and organization of these receptors becomes distorted in a dish due to an altered cytoskeleton which affects the efficacy of the receptor-targeted drug. Collectively, stress and distortion of the cell cytoskeleton greatly reduces the predictive ability of in vitro studies.
Culturing cells in 3D solves all of these problems and facilitates the translation of results. In 3D, cell shape, function, and surface receptors (drug targets) are restored. The cells grow in a multi-layer fashion instead of in a monolayer. They are able to interact with one another, form natural cell-cell attachments, and communicate with the extracellular matrix. Transport of molecules to and from the cells occurs as it does in the human body, providing a more realistic model of the challenges and physical barriers that exist during drug delivery and transport. 3D cell culture enables researchers to more accurately model and study complex events that take place in the human body and translate those findings to humans.