Delicacy of Differentiation by the Schultz-Dale Test as Revealed by End-Point Determinations on Rodent Sera

Abstract

Summary: A procedure is described whereby the Schultz-Dale test will yield end-point determinations after the manner of the serial dilution method employed with the precipitin test. As judged by investigations on sera of rodents of varying degrees of inter-relationship, the Schultz-Dale test is somewhat more sensitive than is the precipitin test (ring test). Sera differentiable by the latter are more sharply differentiated by the Schultz-Dale test. When passive sensitization is produced with very specific antisera, the Schultz-Dale test will differentiate between sera which are not differentiable by the precipitin test (ring test) employing antisera of the same order of specificity.