Coexistence of a circulating IgG-albumin complex and a gamma heavy chain in the same patient

A patient with an IgG-albumin complex and a gamma heavy chain in his serum was studied by crossed immunoelectrophoresis. The IgG-albumin complex was not dissociated after incubation with 2-mercaptoethanol but it was after incubation with sodium dodecyl sulfate. Evidence was obtained that the IgG and albumin were held together by noncovalent bonds, possibly due to an antigen-antibody reaction.