Inhibition of rosette formation of IgE-bearing rat mast cells by disodium chromoglycate.

The interaction of reaginic antibody with specific antigen was studied by the rosette formation of peritoneal rat mast cells. The mast cells were obtained from actively sensitized rats or were passively sensitized in vitro. Rosette formation was of a higher degree with mast cells of actively sensitized rats; in this case 58% of the cells showed a strong rosette-forming effect (blinding more than 5 SRBC). No rosette formation was detected in 18% of the cells. With passively sensitized rat mast cells, rosette formation was 45% and 22%, respectively. Rosette formation of both actively and passively sensitized mast cells could be inhibited by disodium chromoglycate (DSCG); the inhibitory effect of 20 micrograms and 200 micrograms of the drug was the same, and neither dose caused a full inhibition. It is suggested that the linkage of specific antigen to the surface of sensitized mast cells can be inhibited by DSCG in vivo.