Antimeasles immunoglobulin G and virus-neutralizing activity in sera of patients with otosclerosis.

Otosclerosis is considered as an organ-specific measles virus (MV)-induced disease. The majority of people are infected with MV during childhood, and the immune activation is characterized by a lifelong persistence. Any kind of depressed systemic antimeasles reaction can lead to induction of a local immune response in the inner ear. MV proteins were resolved by conventional polyacrylamide gel electrophoresis in the presence of a denaturing detergent. In subsequent Western blot, healthy blood donors demonstrated a stronger reaction against most proteins than age- and sex-matched otosclerotic patients. Different serum dilutions were tested for neutralizing activity against constant MV concentration. Nearly complete viral neutralization was achieved with samples containing inactivated complement and in immunoglobulin-G-containing fractions, and activity in sera from patients with confirmed otosclerosis was significantly weaker than in healthy individuals. Our observations are consistent with viral participation in otosclerotic pathogenesis, but it is difficult to say if the diminished antimeasles humoral response is a consequence of or the cause for a local measles infection.