[Catalytic antibody and its medical applications]

Catalytic antibodies will not only provide new insight into the general potential of natural enzymes, but may also afford novel catalysts to facilitate reactions not catalyzed by natural enzymes. One goal of studying catalytic antibodies is to generate tailor-made catalysts for applications in medicine. An example of a possible use with catalytic antibodies is related to the action of prodrugs. In the rational design of prodrugs, it is necessary to consider (a) what structural modifications of the parent molecule are necessary to reduce or eliminate the particular undesirable effects, and (b) what enzymes are available in vivo to regenerate the parent molecule from the prodrug. However, the design of structurally related analogues of a parent molecule is limited by the enzyme's specificity, the type of reaction catalyzed, and the enzyme distribution and level. Using catalytic antibody technology for the novel design of prodrugs allows for effective structural modifications of the molecule in question. It is also a valuable aid in overcoming the problem of drug delivery by using bi-functional chimeric antibody technology, through which site-specific antibodies are combined with antibodies catalyzing reactions that cannot be accomplished by natural enzymes in vivo. In this review, we describe the first example of prodrug activation via catalytic antibodies as well as future aspects of catalytic antibodies of medical interest.