Microcarrier systems show great potential for the large-scale growth of cells and the production of their metabolic products. Our long-term objective is to develop an improved microcarrier for growing fastidious, anchorage-dependent cells. The goal of this research is to understand the biochemical basis for the differences in cell growth and behavior observed on the several commercially available microcarriers and our Bioglas microcarrier beads. The specific objectives are to determine if the differences in the levels of endogenous proteolytic enzymes and the differences in the levels of specific arachidonic acid metabolites produced by cells on the various microcarrier substrates contributes to differences in cell growth and behavior on these substrates. The Phase I objective will be to compare growth, adhesiveness and morphology of MRC-5 cells on five microcarriers (Cytodex I, Cytodex III, Ventregel, Biosilon and Bioglas) under normal growth conditions and under conditions in which the functioning of endogenous proteases is suppressed. And, to compare cell growth, adhesiveness and morphology on the same substrates under normal growth conditions and under conditions in which the synthesis of cyclooxygenase and/or lipoxygenase products of arachidonic acid is modulated. These results will aid in developing an improved Bioglas microcarrier and more productive microcarrier protocols.