Immunological behaviour of HGH from plasma of patients with familial dwarfism and high IR HGH in a radioimmunoassay system using the cross reaction between HGH and HCS

Using a 'hybrid' system, namely the reaction ¹²⁵I HGH and antiserum against HCS, the authors found no difference in the immunological behavior of the HGH from the plasma of familial dwarfism with high IR HGH as compared to the control groups. The similarity found in the dilution curves may point to the fact that there are probably no structural changes located in the common antigenic sites of the molecules of HGH and HCS. It does not exclude, however, the possibility that the HGH molecule of the patients with the syndrome of familial dwarfism and high plasma IR HGH is structurally different from normal HGH in other regions and that such differences may render the molecule biologically inactive. The lack of difference in immunological specificity may also be due to a defect in the receptor sites on the relevant cells.