The antigenic epitopes of human grown hormone as mapped by monoclonal antibodies

The antigenic epitopes of human GH (hGH) have been investigated using monoclonal antibodies (Mabs) to hGH. A panel of 12 Mabs was incorporated into two-site binding assays in order to investigate the antigenic surface of hGH. Nine reaction patterns were observed. The Mabs were further characterized in terms of their cross-reactivity with human placental lactogen, human PRL, with recombinant hGH molecules (MetLeu8hGH, Met14hGH), and with fragments derived from enzymatic or chemical digestion of hGH. These studies provided information on the antigenic sites that are shared with human placental lactogen and on the N-terminal and C-terminal regions of the hGH molecule. Based upon these findings, we tentatively suggest the epitope model for hGH comprising at least 10 antigenic sites (epitopes) which may be grouped into five antigenic regions.