Production and characterization of antibodies against irradiated human erythrocytes membrane proteins

Gamma irradiation affects people in several situations, with few if any sensitive biological assay of its action. Nucleic acids and proteins are affected by radiation, but only the former was used in most dosimetric techniques. The irradiation of proteins promotes structural modifications attributed to free radicals from water radiolysis. Theoretically, antibodies induced by irradiated proteins could recognize these radical-related new epitopes, allowing their use as a probe. Human erythrocyte membrane proteins (HEMP), few and well defined molecules, are certainly exposed to radiation, being the ideal target. With this rationale, we study the production of antibodies in mice immunized with 60 Co irradiated HEMPs. Menbranes from hypotonic lysis with differential centrifugation of A+ erythrocytes, were irradiated in a Gammacell 220 with 400, 800 and 1600 Gy, and used as immunogen for Balb/c mice, after SDS-PAGE. Irradiated HEMP induced antibodies recognize only irradiated human erthrocytes in an intact cell indirect immunofluorescence assay (ICIIFA). When used in Wester-blot against non-irradiated HEMPs, those sera recognize most proteins, suggesting a pool of abs directed both to native, as detected by Western Blot, or irradiated, as detected by ICIFA, HEMPs. Those data confirmed our assumptions, allowing the use of those abs in the search for a method of biological dosimetry. (author). 18 refs., 3 figs