BRONCHIAL PROVOCATION WITH CAT ALLERGEN - CORRELATION BETWEEN THE INDIVIDUAL IGE-CRIE PATTERN AND THE OCCURRENCE OF A LATE ALLERGIC REACTION

Twenty-one mild asthmatic patients allergic to cat dander underwent a bronchial provocation test (BPT) with a cat extract. An early allergic response (EAR) was observed in all 21 patients and a late allergic re sponse (LAR) in 8/21 patients. In the EAR, the patients with subsequen t LAR had a greater fall in FEV(1). Their baseline FEV(1), and total d ose of inhaled allergen were not significantly different from patients who did not develop a LAR, but their serum specific IgE level was hig her. Crossed immunoelectrophoresis (CIE) of the same cat extract showe d that it contained eight different proteins. An IgE-CRIE was obtained from all 21 patients, using radiolabelled anti-IgE and autoradiograph y. Radiolabelled standards allowed a semiquantitative scoring of the r adiostaining. The CRIE pattern of the eight patients with LAR showed a higher score of radiostaining and a greater number of proteins bound to IgE. The two major allergen cat albumin and Fel ii I bound equally to IgE of patients with and without LAR whereas another protein (antig en No. 7) bound to IgE of 100% of patients with LAR but of only 38% of patients without LAR. These data suggest that the pattern of the IgE response to specific proteins of a cat extract may be related to the o ccurrence of LAR after BPT with this allergen.