The molecular organization of the protein HC-IgA complex (HC-IgA).

Complexes of protein HC and monoclonal IgAl or IgA2 or polyclonal IgA were isolated from human blood plasma.Dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting showed that all complexes contain three types of chains: two light immunoglobulin chains, one regular IgA a-chain, and one chain with Mr = 90,000 carrying both a-chain and protein HC epitopes.