ANALYSIS OF CHARGE OF KAPPA AND LAMBDA CHAIN-CONTAINING SERUM IMMUNOGLOBULIN-A BY IMMUNOBLOTTING AND DENSITOMETRY

A novel method for studying the charge distribution of different subcl asses of serum immunoglobulin A (defined by the light chains) is descr ibed. Affinity-chromatography purified immunoglobulins were focused in polyacrylamide gel and were then transferred electrophoretically onto nitrocellulose membranes. The transferred immunoglobulins were detect ed by rabbit antiserum to human kappa (kappa) or lambda (lambda) chain , swine anti-rabbit IgG, rabbit anti-peroxidase antibodies and peroxid ase, together with a substrate solution comprising H2O2 and diaminoben zidine. Finally, the developed membranes were made transparent with Tr iton-x 114, scanned at 485 nm with a densitometer to obtain quantitati on of charge distribution.