REAL-TIME CONFOCAL LASER-SCANNING MICROSCOPY - POTENTIAL APPLICATIONSIN SPACE-MEDICINE AND CELL BIOLOGY

Photodynamic therapy (PDT) in which tissues may be rendered fatally li ght-sensitive represents a relatively novel treatment for cancer and o ther disorders such as cardiovascular disease. It offers significant a pplication to disease control in an isolated environment such as space flight. In studying PDT in the laboratory, low energy lasers such as HeNe lasers are used to activate the photosensitized cellular target. A major problem associated with these studies is that events occurring during actual exposure of. the target cells to the system cannot be e xamined in real time. In this study HeLa cells were photosensitized an d photodynamic activation was accomplished using the scanning microbea m om a confocal laser scanning microscope. This form of activation all owed for simultaneous photoactivation and observation and facilitated the recording of events at a microscopic level during photoactivation. Effects of photodynamic activation on the target cells were monitored using the fluorophores rhodamine 123 and ethidium homodimer-1. Potent ial applications of these forms of analyses to space medicine and cell biology are discussed. (C) 1998 Elsevier Science Ltd. All rights rese rved.