Work

In vitro and in vivo photosensitizing capabilities of 5-ALA versus Photofrin� in vascular endothelial cells

Year: 1999

Type: article

Abstract: BACKGROUND AND OBJECTIVE: The objective of the present study was to evaluate the feasibility of photodynamic therapy (PDT) for complicated hemangiomas. The photosensitizing activities of 5-aminolevulinic acid (5-ALA) and Photofrin were evaluated in vitro with human dermal microvascular endothelial cells (MEC) and in vivo with the chicken cox comb. STUDY DESIGN/MATERIALS AND METHODS: The in vitro absorption and photosensitizing activities of 5-ALA and Photofrin were examined in a MEC culture system. The percentages of MEC killed by different drug concentrations at a wavelength of 630 nm were measured by either live/dead or lactate dehydrogenase-released assays. Similarly, the in vivo biological activities of 5-ALA and Photofrin exposed to different total light dosages at 630 nm were studied by determining the amount of necrosis produced in chicken combs. RESULTS: MEC incubated with 5-ALA at a concentration of 35 microg/ml and exposed to laser light at 630 nm at a power density of 100 mW/cm2 showed a 50% cell kill. MEC incubated with Photofrin at a concentration of 3.5 microg/ml and exposed to laser light at 630 nm at a power density of 100 mW/cm2 showed a 50% cell kill. Chicken combs that received 200 mg/kg of 5-ALA exposed to laser light at 630 nm at a power density of 100 mW/cm2 had an injury depth of 362.5+/-27.6 microm at histologic examination. Combs exposed to a power density of 100 or 120 mW/cm2 showed injury depths of 732.5+/-29.1 and 792.5+/-36.0 microm, respectively. Chicken combs that received 2.5 mg/kg of Photofrin exposed to laser light at 630 nm at a power density of 80 mW/cm2 had an injury depth of 535.6+/-22.3 microm at histologic examination. Combs exposed to a power density of 100 or 120 mW/cm2 showed injury depths of 795.8+/-32.5 and 805.2+/-49.1 microm, respectively. CONCLUSION: Both 5-ALA and Photofrin have the capability to destroy MEC in vitro and vasculature in vivo. However, Photofrin achieved a higher degree of cell kill and tissue destruction at lower drug concentrations and at lower power densities.

Source: Lasers in Surgery and Medicine

DOI: 10.1002/(sici)1096-9101(1999)24:3<178::aid-lsm2>3.0.co;2-w

Authors: Cheng-Jen Chang, Chung-Ho Sun, Lih-Huei L. Liaw, Michael W. Berns, J. Stuart Nelson

Institutions: Chang Gung Memorial Hospital, University of California, Irvine, Beckman Laser Institute and Medical Clinic

Language: English

Topic: Photodynamic Therapy Research Studies

Subfield: Pulmonary and Respiratory Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: bronze