A high pressure-induced process has been developed to recover antigens from immunoadsorbents, without denaturing either the antigen, or the antibodies bound onto supports. The addition of chemicals is not needed to recover the product. Two variants of a model antigen were considered: (i) the Escherichia coli beta-galactosidase and (ii) a chimerical E. coli beta-galactosidase. Two and three-dimensional immunoaffinity supports (membranes and beads) were used.