Reliability of the Survival Dose Estimated from in Vitro Cytotoxicity Testing in Photodynamic Therapy

ABSTRACT

Assessment of a new photosensitizer in a photodynamic therapy implies in vitro cytotoxicity testing whose outcome is influenced by a host of factors which characterize underlying photochemistry, photophysics and photobiology. To determine the reliability of the outcome we evaluate reliability of a survival dose estimated from a single light dose-response curve in a neutral red uptake cytotoxicity testing by means of validation measurements. Each light dose-response curve is build from the relative viability data obtained using a 96-wells micro-plate. The validation measurements performed with two human (8 MG BA andMCF-7) and two animal (LSCC-SF-Mc29 and LSR-SF-SR) tumor cell lines treated with two phthalocyanines (ZnS₃Pc and ZnS₃Pc) prove that a reliable test output can be derived from a single micro-plate.

Keywords:

• Photodynamic therapy
• phthalocyanines
• tumor cell lines
• neutral red uptake cytotoxicity test
• survival light dose