The use of three-dimensional collagen gels for the study of tumour cell invasion in vitro: experimental parameters influencing cell migration into the gel matrix.

We have been using three-dimensional gels of native collagen fibres as a substratum for the study of cell migratory behaviour. The objective of this work has been to develop an experimental model system for the study of tumour cell invasion. Data are presented in this communication concerning the effects of a number of experimental parameters on the migration of human foreskin fibroblasts (normal) and a Syrian hamster melanoma cell line (tumour) into three-dimensional gels of native collagen fibres. We find that the migration of both these cell types into the gel matrix is affected by the concentration of collagen in the gel, as well as by the initial density of cells plated onto the gel and the density of cells in the stock culture dishes. These results are discussed in terms of the control of cell migration into the gel and also demonstrate the potential utility of this model system for the study of tumour cell invasion.