Abstract
Antibodies raised in rabbits to tropoelastin isolated from lathyritic chick aorta were conjugated with ferritin and used to identify and locate elastin-containing elements in sections of aortic tissue from developing chicks. The ferritin-antibody conjugate was associated with a network of fine filaments with a diameter of 3-5 nm which, in the 8-10 day old chick embryo aorta, was distributed between and around small but recognizable elastic fibers. In older aortic tissue this ferritin-labelled material was seen principally in loose association with the periphery of developing elastic fibers. The microfibrils did not interact with the ferritin-antibody conjugate. Treatment of chicks with beta aminopropionitrile did not interfere with the accumulation of ferritin-labelled filaments on these small elastic fibers, suggesting that the mechanism of addition of new material onto growing fibers may be independent of cross-linking.