DETERMINATION OF THE NUMBER OF FAB(1) PIECES WHICH REACT WITH HIGH-MOLECULAR-WEIGHT ANTIGENS (REPRINTED FROM IMMUNOL COMM, VOL 11, PG 261, 1982)

The sedimenting-droplet technique was used for the determination of th e masses of immune Fab1 pieces which may bind to antigenic sites on th ree haemocyanins. Similar experiments were conducted on three viruses which belong to the Tobamo group. It was calculated that 384 homologou s Fab1 pieces could bind to a molecule of the haemocyanin of Burnupena cincta and 950 homologous Fab1 pieces to a virion of tobacco mosaic v irus. By taking special precautions the number of undergraded antibody molecules which can bind to a Tobacco mosaic virus particle may be de termined with the same technique.