The effect of culture filtrates of oral strains of black‐pigmented Bacteroides on the matrix production of chick embryo cartilage cells in vitro

Culture filtrates of strains of Bacteroides gingivalis and Bacteroides asaccharolyticus contain a heat stable factor which inhibits the production of extracellular matrix by chick embryo chondrocytes and which causes vacuolization of these chondrocytes. This morphological effect appeared to be reversible. Strains of the saccharolytic species Bacteroides melaninogenicus did not have these effects. The significance of this cytotoxic effect for the etiology of periodontal diseases is discussed.