Lectin blot analysis of IgA1 purified from mIgA-MIDD serum under reducing and non-reducing conditions.

IgA1 purified from mIgA-MIDD serum was pretreated in SDS buffer with or without 2-ME, separated by SDS-PAGE under non-reducing (lane 1) or reducing (lane 2) conditions, and then subjected to western blotting with an anti-IgA1 mAb (A), ConA (B), and WFA (C). Cross-reacting bands were detected using Konica immunostaining kit (Konica, Tokyo, Japan) for anti-IgA1 mAb and ConA and Western Lightning Chemiluminescence Plus (Perkin-Elmer, Boston, MA) for WFA. A Gal deficient IgA (lane 3), enzymatically deglycosylated with neuraminidase and galactosidase, was used as a positive control for WFA lectin. mIgA-MIDD, monoclonal immunoglobulin deposition disease associated with monoclonal IgA; 2-ME, 2-mercaptoethanol; ConA, jack bean lectin concanavalin A; WFA, Wisteria floribunda agglutinin.