Restriction of human immune antibodies to heavy-chain variable subgroups.

Human immune antibodies such as anti-Rh and anti-Kell antibodies were tested in hemagglutination and hemagglutination inhibition experiments for VH subgroup composition. A striking VH subgroup restriction was found in several of these groups of antibodies. In the majority of cases there was a restriction to one particular VH subgroup for a single antibody specificity in a given individual. In some cases there was also an overall restriction to one particular subgroup for antibodies with the same antibody specificity. This was particularly pronounced for anti-D antibodies, which was primarily restricted to VHII, and for the anti-Kell, which was particularly related to VHIII. Subgroup-specific antigens for all the main VH subgroups were blocked on combination of the antibody molecule with antigen. No relation was found between VH restriction and restriction to IgG subclass, or genetic markers or chi and lambda light-chain type.