Allergy to rabbits. III. Further identification and characterisation of rabbit allergens.

Crossed immunoelectrophoresis and crossed radio-immunoelectrophoresis techniques have been employed for analysis of extracts of various rabbit source materials to identify rabbit allergens in addition to the already described Antigen R1 (AgR1). Urine and dander extracts were found to contain only low levels of AgR1 and its presence in urine was as a contaminant due to mode of collection--it was not present in urine collected directly from the bladder. Other allergens were only recognised by highly rabbit-sensitive individuals, one in particular (Ag2) being present in several source materials. Serum albumin proved to be of minor allergenic importance and except for dander its presence was only in minimal amounts. As both AgR1 and Ag2 are significant components in extracts of fur and dust these extracts are therefore most recommended for use in investigations of individuals sensitive to rabbits.