SEROLOGIC CROSSREACTIONS AMONG PRIVATE IMMUNOGLOBULINS

We have generated and characterized 50 murine monoclonal antibodies (m Ab) specific for baboon IgG, We examined crossreactivity of these mAb to baboon IgM and immunoglobulin (Ig) of various other primates includ ing human, chimpanzee, rhesus monkey, cynomologous monkey, and African green monkey, Those mAB that crossreacted with human IgG were further examined using myeloma proteins for specificity to human Ig subclasse s, One mAB crossreacted with all four human IgG subclasses and with hu man IgM, We further analyzed this reactivity utilizing Bence Jones pro teins representative of various light (L) chain germline gene family p roducts, This mAB reacted with Bence Jones proteins indicating the rec ognition of a kappa (kappa) L chain specificity associated with the ka ppa I, kappa III, and kappa IV subgroups, but not with kappa II. Based on the differences between KII germ line gene encoded L chains and th e other kappa L chain subgroups, we ascribe this reactivity to six ami no acids that define a discontinuous epitope.