Developmental aspects of immunologically characterized proteins.

The spectrum of clinical tests for proteins characterized by their antigenic rather than by their enzymatic properties has been very limited, and still is today. This is mainly due to technical problems in the development of tests for such "antigens". The recently developed hybridoma technology has supplied us with the urgently needed new approach to overcome these problems. It is now possible to develop specific monoclonal antibodies against any determinant on antigens in any tissue, membrane or extract without the need to prepare antigens of high purity. Diagnostically valuable tissue marker molecules without known biological activity have become accessible, and can be detected and quantitated in tissues and body fluids with the new reagents. In most of the tests that will become available now or in the near future, polyclonal antisera will be substituted by monoclonal antibodies. Future developments, however, will exploit the advantages of the new technology to their full extent. In this paper, the advantages and disadvantages of monoclonal antibodies are evaluated and illustrated by the example of monoclonal antibodies to human kidney tissue antigens. Future developments comprising all fields of clinical diagnosis as well as applications in therapy are discussed.