THE RHESUS-D ANTIGEN - A DICYCLOHEXYLCARBODIIMIDE-BINDING PROTEOLIPID

Google Scholar
  • 1 January 1983
    • journal article
    • research article
    • Vol. 110  (2) , 127-134
Abstract
Previous studies on the human Rhesus D antigen revealed several similarities between the D antigen and proteolipids. Proteolipids are a family of low-MW, hydrophobic proteins that are soluble in chloroform/methanol. Many proteolipids bind dicyclohexylcarbodiimide (DCCD), an ATPase inhibitor. For determination of whether the D antigen was a proteolipid, the chloroform/methanol solubility and DCCD binding of the antigen were investigated. DCCD specifically inhibited the binding of anti-D IgG to Rh-positive red blood cells and to partially purified D antigen as determined by enzyme-linked immunoassays. The antigen was not only soluble in chloroform/methanol but was purified to apparent homogeneity by extraction with these solvents and subsequent discontinuous sucrose gradient centrifugation. The antigen''s chloroform/methanol solubility, DCCD binding, low MW and previously reported phospholipid dependence allow classification of the D antigen as a proteolipid. The discovery that the D antigen is a proteolipid provides further clues to the antigen''s cellular function.