PHA selection electrophoresis--a screening method for monomeric IgM

Pentameric IgM is precipitable by PHA whereas monomeric IgM is not. During electrophoresis in PHA-containing agar gel pentameric IgM is selected by precipitation from concomitant monomeric IgM which may be visualized separately as a precipitation line with specific antibody. This antibody-like use of the lectin in PHA selection electrophoresis provides a quick and simple method of screening macroglobulinemic sera and other biological fluids for the presence of naturally occurring monomeric IgM subunits.