The isolation of antibodies specific for 5-methyl-cytidine-bovine serum albumin.

By coupling 5-Methyl-cytidine to bovine serum albumin, a conjugate containing 18 mol of 5-Methyl-cytidine per mol of BSA was prepared. Antibodies to this conjugate were produced by immunization of rabbits. Specificity of the antibody was assessed by gel diffusion in agar containing excessive amounts of the carrier BSA. A slight cross-reactivity with cytidine was eliminated by adsorption on the cross-reacting antigen. The isolation of 7S immunoglobulin from the total globulin fraction was accomplished by chromatography on DEAE Sephadex-A-50, and a method for the rapid quantitation of the antibodies showed that 12.7% of the IgG protein are monospecific against 5-Methyl-cytidine bovine serum albumin.