Effect of hypothermia on the merocyanine 540-mediated purging of hematopoietic cells. J Hematother 1997 Feb;6(1):31-9
Date
02/01/1997Pubmed ID
9112216DOI
10.1089/scd.1.1997.6.31Scopus ID
2-s2.0-0030953547 (requires institutional sign-in at Scopus site) 10 CitationsAbstract
Merocyanine 540 (MC540)-mediated photodynamic therapy (PDT) inactivates experimental leukemia, lymphoma, and neuroblastoma cells by a singlet oxygen-mediated mechanism but is relatively well tolerated by normal pluripotent hematopoietic stem cells and granulocyte/macrophage progenitors (CFU-GM). MC540 is currently undergoing phase I clinical testing for the extracorporeal purging of autologous bone marrow and peripheral blood stem cells. We report here that performing MC540-mediated PDT at 4.7 degrees C (hypothermia) instead of at ambient temperature enhanced the photoinactivation of L1210 cells and CFU-GM but left the photoinactivation of K562 cells unchanged. Hypothermia reduced dye binding in K562 but not in L1210 cells, whereas the photogeneration of lipid hydroperoxides (LOOH) was affected in neither cell line. Post-PDT incubation at 4 degrees C delayed the decay of LOOH and enhanced the photoinactivation of CFU-GM as well as L1210 and K562 cells. Taken together, these results suggest that hypothermia interfered with the repair of potentially lethal photodynamic damage. They stress the importance of temperature control during and immediately after the photochemical purging of autologous bone marrow and peripheral blood stem cells.
Author List
Yamazaki T, Sieber FAuthor
Fritz Sieber PhD Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBone Marrow Cells
Bone Marrow Purging
Bone Marrow Transplantation
Cell Survival
Cold Temperature
Dose-Response Relationship, Radiation
Female
Fluorescent Dyes
Hematopoietic Stem Cell Transplantation
Humans
Kinetics
Leukemia
Leukemia L1210
Lipid Peroxidation
Lipid Peroxides
Mice
Mice, Inbred DBA
Pyrimidinones
Radiation-Sensitizing Agents
Tumor Cells, Cultured