Abstract
It is clear that the anaphylactic reaction is caused by the combination between tissue antibody and antigen. In this connection, quantitative relation between the concentration of tissue antibody and the concentration of antigen required to cause an anaphylactic contraction of the intestine was studied in the previous report (Ishizaka et al., 1956) . As a result of this, it was proved that the relation is hyperbolic provided that both concentrations were represented in terms of logarithmic scale. In other words, the inhibition of anaphylactic contraction due to antigen excess was never observed though its reason remains unexplained.
The present communication records additional peculiarities observed in the quantitative proportion between antibody and antigen to yield anaphylactic reaction, especially in comparison with precipitation and complement fixation reaction.
