Electrophoretic variation of serum alpha1-antitrypsin treated with neuraminidase

Purified or crude sera of several different phenotypes of alpha1-antitrypsin were treated with neuraminidase. The mobility of the alpha1-antitrypsin zone was delayed on starch gel electrophoresis following incubation. Treated, M-type alpha1-antitrypsin migrated in a manner similar to the untreated S type. Treated S migrated in a similar way to the untreated Z, and treated Z did so more slowly or cathodally. After exhaustive treatment, alpha1-acidglycoprotein bands appeared near the usual M or F positions. Treated samples still possessed the antigenic activity of alpha1-antitrypsin. The concentration and trypsin-inhibitory capacity were not changed by treatment. Several evaluations and considerations are discussed concerning the metabolism of some types of alpha1-antitrypsin.