Gradient chamber. A new method for migratory fractionation of inflammatory response in vivo.

A new and simple method to study the inflammatory process in vivo using a diffusion-migration chamber is described. The influx of inflammatory elements into chambers was studied by light and electron microscopy. This gradient chamber (GC) was developed by substituting one of the filters of the classic diffusion chamber by a polyvinyl sponge cylinder. In the implanted chambers this plastic framework acts as a tridimensional gradient, through which the acute and chronic inflammatory processes migrate with different speeds and are thus divided into two distinct and widely separated waves. By delaying the overlapping of the first wave by the second, this bioassay allows a longer time for observation of the cell-matrix or cell-matrix-graft interaction during the first inflammatory wave and permits studies by methods such as immunocytochemistry, histochemistry or biochemical analysis.