Modification of the immunogenicity and antigenicity of rat hepatoma cells. I. Cell-surface stabilization with glutaraldehyde.
gamma-Irradiated rat hepatoma cells are immunogenic in syngeneic WAB/Not rats, so that immunized animals are protected against tumour-cell challenge and circulating tumour-specific antibody is produced. Treatment of the immunizing cells with glutaraldehyde at concentrations of 0.001% or greater for 30 min rendered these cells non-protective in tumour-rejection tests and no longer able to induce significant formation of specific antibody. However, tumour-specific antigens were shown to be expressed upon treated cells; they specifically bound tumour-specific antibody from syngeneic immune sera assessed in indirect membrane-immunofluorescence tests. Also, these cells specifically absorbed antibody from immune or tumour-bearer sera, as demonstrated in the indirect membrane-immunofluorescence test or a complement-dependent 51Cr-release test. Alloantigen expression was not influenced by glutaraldehyde treatment, although glutaraldehyde-treated hepatoma cells failed to induce alloantibody formation in KX/Not rats. Polyacrylamide-gel electrophoresis of treated cells, surface-labelled with 125I, indicated that extensive cross-linking of the surface protein occurred as a result of glutaraldehyde treatment. The present findings establish that although the expression of a tumour-specific antigen is necessary for the induction of immuno-protection against tumour-cell challenge, this alone is not a sufficient condition for eliciting tumour immunity.
D000818:Animals; D000917:Antibody Formation; D000951:Antigens, Neoplasm; D002462:Cell Membrane / Q000187:drug effects*; D002860:Chromium Radioisotopes; D003298:Coombs Test; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D005720:Gamma Rays; D005976:Glutaral / Q000276:immunology; D007140:Immunoglobulin Fab Fragments; D007457:Iodine Radioisotopes; D007518:Isoantibodies / Q000276:immunology; D008114:Liver Neoplasms, Experimental / Q000276:immunology*; D008297:Male; D011830:Radiation Effects; D051381:Rats
D000951:Antigens, Neoplasm; D002860:Chromium Radioisotopes; D007140:Immunoglobulin Fab Fragments; D007457:Iodine Radioisotopes; D007518:Isoantibodies; D005976:Glutaral