SERUM IGA IMMUNE-RESPONSE TO INDIVIDUAL ROTAVIRUS POLYPEPTIDES IN YOUNG-CHILDREN WITH ROTAVIRUS INFECTION

A human IgA-radioimmunoprecipitation assay (IgA-RIPA) utilizing the ga lactose-binding lectin jacalin from the jack-fruit Artrocarpus integri folia was developed. Among the human immunoglobulins, jacalin binds sp ecifically to immunoglobulin A. The IgA-RIPA was used to characterize the serum IgA response to individual rotavirus polypeptides in nine pa ired sera from children (8-34 months of age) with an acute rotavirus i nfection. In acute sera the IgA response was mainly directed against t he inner capsid proteins VP2 and VP6, with VP2 surprisingly being the most immunogenic protein while in the convalescent sera, the IgA respo nse was directed not only against structural but also against non-stru ctural proteins.