Cystic fibrosis: fractionation of fibroblast media demonstrating ciliary inhibition.

A chromatographic fraction has been identified in media from fibroblast cultures derived from 15 of 18 cystic fibrosis patients and 8 of 10 heterozygotes that inhibits ciliary activity, as judged by the oyster gill assay. The analogous fraction of media from cultures of fibroblasts derived from 11 normal individuals did not inhibit ciliary activity under the experimental conditions used. The chromatographic fractions containing the ciliary inhibitory activity from both fibroblast media and sera of cystic fibrosis patients and heterozygotes eluted in the same position from diethylaminoethyl-cellulose at pH 8.5. Although the serum ciliary inhibitor had consistently been detected in a fraction that contained predominantly immunoglobulin G, results of the fractionation of fibroblast media demonstrate that the ciliary inhibitor is present in a protein fraction containing three species of different molecular weight and in which IgG cannot be detected by the techniques used.