ANTIBODY-TARGETED PHOTOLYSIS

The technique of Antibody Targeted Photolysis (ATPL) is reviewed from an historical perspective with a summary of the literature since the f irst experiments were performed in 1983. Attention is given to both th e biological and photophysical properties of the various immunoconjuga tes that have been developed. References to critical discoveries and c ompeting technologies in the photodynamic literature are given. Topics include: synthesis of immunoconjugates, in vitro vs. in vivo toxicity , in vivo biodistribution, immunoconjugate delivery, photosensitizer s election based on photophysical properties, light delivery for specifi c applications, oxygen requirements, and other physicochemical phenome na. A mathematical model of the dynamics for cell killing based upon t he transport of phototoxins to the cell surface is developed. A genera lized set of coupled differential equations is given, which convenient ly summarizes the manifold requirements stressed earlier for successfu l cell killing. Solutions are then presented for an idealized set of c onditions appropriate for an isolated tumor cell. Suggestions for furt her improvements and follow-up experiments are made that could help in the evolution of ATPL into a useful clinical therapy and/or probe for cell biological studies.