Serological distinciton of heavy chain variable regions (VH subgroups) of mouse immunoglobulins. I. Common VH determinants on the heavy chains of mouse myeloma proteins having different binding sites.

16 of more than 100 mouse myeloma proteins, including 3 proteins of the IgG2a class and 13 of the IgA class, were shown to have a similar heavy chain variable region (VH) antigen(s) (U10-173). The proteins bearing these antigenic determinants (U10-173+ proteins) represented at least five different ligand-binding specificities. These findings, taken togeter with available sequence data for VH regions of U10-173+ proteins, have led us to conclude that U10-173 defines a small number of related VH subgroups. The ability to detect VH subgroups in mice by serological means, as has been done in humans also, promises new and useful kinds of VH markers for immunologic study.