Disruption of antigen-antibody complexes often requires drastic conditions. High-pressure application to such complexes would lead to the rupture of antigen-antibody interactions as suggested by Olson et al. The results presented here attempted to determine the usuability of high pressure as an alternative antigen-antibody separation ration process using a beta-galactosidase-anti-beta-galactosidases complex as a model. For this purpose, pressure- changes concerning the biologic functions of two beta-galactosinases and polyclonal-related antibodies were studied in the 0-500 MPa pressure range for temperatures varying from 4 to 35 degrees C. After pressure release, catalytic activity of the beta-galactosidases was measured. In addition, enzyme-linked immunosorbent assay (ELISA) was used to examine antibody recognition after these proteins had been pressure-treated. Recognition of antigens by the pressurized antibodies was also investigated by ELISA. This work allowed us to show the possible design of a high-pressure separation process with a beta-galactosidase-anti-beta-galactosidase tandem (or fusion proteins possessing Escherichia coli beta-galactosidase as a tag). For pressures below 250 MPa within the temperature range investigated, no irreversible drastic loss of activity or dramatic alterations in antigen-antibody recognition was observed. Moreover; interesting pressure and temperature effects leading to changes in antigenic reactivity were observed and are discussed.