Irradiation of cells attached or suspended by rubber policeman or by trypsin influences the extent of DNA strand breaks induced by ionizing radiation.
Chilled B16CL4 mouse melanoma cells in phosphate-buffered saline were exposed to ionizing radiation before or after harvesting by gently scraping with a rubber policeman. Cells irradiated when attached had fewer DNA strand breaks than cells that were irradiated in suspension. Dose-response studies indicate that the rate of induction of DNA strand breaks by ionizing radiation is 1.5-fold greater in suspended cells. Irradiation after release of the cells by trypsinization also results in more breaks than irradiation when attached, but this method of harvest is not as damaging as release by rubber policeman. Strand breaks in unirradiated cells are unaffected by the method of cell harvest. These studies suggest that, in radiation studies, care should be exercised to avoid the introduction of artifacts resulting from the methods used to harvest and irradiate cells.
Hill
H Z
HZ
Department of Radiology, New Jersey Medical School, Newark 07103-2714.
Hill
G J
GJ
D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects*; D002460:Cell Line; D003584:Cytological Techniques; D004249:DNA Damage; D004273:DNA, Neoplasm / Q000528:radiation effects*; D066298:In Vitro Techniques; D008546:Melanoma, Experimental / Q000473:pathology; D051379:Mice; D014357:Trypsin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000528:radiation effects
D004273:DNA, Neoplasm; D014357:Trypsin