Simple spectrophotometric analysis of passive and active ear cutaneous anaphylaxis in the mouse

Homologous passive cutaneous anaphylaxis (PCA) and active cutaneous anaphylaxis (ACA) to ovalbumin and DNP-hapten were studied in the ears of female BALB/c mice by means of assessing Evans blue dye leakage. For the quantitative evaluation of PCA and ACA, a hand-held spectrophotometer and the conventional colorimetric method were used to detect the amount of extravasated dye. The value of deltaE*ab (a numerical expression of color) obtained with the hand-held spectrophotometer and the amount of extravasated dye showed a good correlation. In the mouse ear, the sensitivity of PCA reaction was comparable to that of PCA in the rat, and deltaE*ab in the PCA and ACA reactions correlated well with the dilutions of sera and of the antigen, respectively. Thus, using a hand-held spectrophotometer is a simple, quantitative and sensitive method for ascertaining the extent of immediate-type hypersensitivity in the mouse.