[Study of development of autoantibody to beta-adrenergic receptors in asthmatics]

An (125I) iodohydroxybenzyl pindolol (125IHYP) binding inhibition assay was performed. Various dilutions (1:5-1:500) of sera from asthmatics and controls were incubated with canine lung membranes for 60 minutes at 30 degrees C. 125IHYP was added to the membranes for 30 minutes at room temperature in the presence and absence of 10 microM 1-propranolol, and the samples were washed through a Gelman (Type A-E) glass fiber filter using a washing buffer. Radio activity was measured with Aloka gamma counter. In the presence of various serum dilutions from asthmatics, 125IHYP specific bindings of 0.16 fmol to 4.38 fmol were measured. 125IHYP binding was inhibited in a dose-related and nonspecific manner. Serum, albumin, L-histidine and L-cysteine also inhibited 125IHYP specific binding to beta-receptors. Percentages of inhibition of serum from asthmatics on 125IHYP specific finding to beta-receptors were -17.6% to +9.3%, which were compared with identical dilutions of control serum. There was no significant difference in 125IHYP binding inhibition assay between asthmatics and controls. From these results, development of autoantibody to beta-adrenergic receptors could not be detected in this study.