Evidence that the ciliary inhibitor of cystic fibrosis is not an antibody.

An inhibitor of ciliary activity is present in the serum of cystic fibrosis (CF) patients and heterozygotes. Fractionation of CF serum has indicated that the inhibitor is associated with the serum IgG fraction. This study compared the activity of the CF inhibitor to that of rabbit antibody preparations directed against oyster cilia. The aim of this investigation was to determine whether the ciliary inhibitory mechanism in cystic fibrosis is related to a typical immunological reaction. Results from experiments utilizing fluorescent antibody techniques demonstrated that an antiserum directed against oyster ciliated epithelium binds immunologically with both human bronchial and oyster epithelial tissue. Results from experiments utilizing immunofluorescent tracing, passive hemagglutination, double immunodiffusion, and papain digestion, however, indicated that the interaction between the oyster cilia and the CF serum inhibitor was not a typical antigen-antibody reaction.