Use of hyaluronan-derived hydrogels for three-dimensional cell culture and tumor xenografts.

The practice of in vitro three-dimensional (3-D) cell culture has lagged behind the realization that classical two-dimensional (2-D) culture on plastic surfaces fails to mirror normal cell biology. Biologically, a complex network of proteins and proteoglycans that constitute the extracellular matrix (ECM) surrounds every cell. To recapitulate the normal cellular behavior, scaffolds (ECM analogs) that reconstitute the essential biological cues are required. This unit describes the 3-D cell culture and tumor engineering applications of Extracel, a novel semisynthetic ECM (sECM), based on cross-linked derivatives of hyaluronan and gelatin. A simplified cell encapsulation and pseudo-3-D culturing (on top of hydrogels) protocol is provided. In addition, the use of this sECM as a vehicle to obtain tumor xenografts with improved take rates and tumor growth is presented. These engineered tumors can be used to evaluate anticancer therapies under physiologically relevant conditions. Copyright 2008 by John Wiley & Sons, Inc.