Myelin was shown to be a locus for radioantibody absorption in vivo in normal rat brain and in areas adjacent to human brain tumors. The technic of zonal centrifugation in a sucrose-density gradient was used to isolate the myelin-antimyelin complexes and to provide fractions for absorbancy and radioactivity profiling of brain and brain tumor particulate matter. A density shift in myelin from 1.09 to 1.11 was noted when large amounts of radioantibody were adsorbed to it, and this circumstance was utilized to demonstrate the tightness of binding of antibody to myelin even in the presence of overwhelming amounts of brain tissue subsequently added to the antigen-antibody complex. The implications of these findings with regard to future immunochemical studies of brain tumors was discussed.
Supported by Contract AT-(40-1)-3195 with the Atomic Energy Commission.