Defining the Range of Cellular Components, Including Internal Antigens, That Can Serve as Targets of Graft Rejection

The mechanisms underlying rejection of grafted neural tissue are still being defined. Mechanisms relevant to genetically engineered cells are of current interest. To date, attention has focused on major histocompatibility complex (MHC) antigens as targets of graft rejection. Yet even when there is no MHC disparity, as when the patient's own cells are genetically altered, there is still a potential for graft rejection, directed against the novel antigens. We illustrate this in a rat model. METHODS The 9L gliosarcoma line was made to express E. coli-derived b-galactosidase (b-gal). The b-gal is constitutively expressed as a cell-filling internal protein, revealed histochemically /1/. In three experiments, syngeneic CDF hosts were immunized with b-gal before intracerebral im