Publication Date


Advisor(s) - Committee Chair

Thomas P. Coohill, Scott Ford, David Hartman

Degree Program

Department of Biology

Degree Type

Master of Science


The effect of cell geometry on the radiosensitivity to ultraviolet (UV) light has been studied in the CV-1 host cell-capacity system. In this system the macromolecular damage incurred by monolayers of cells cultures as the result of exposure to UV radiation is monitored by testing the ability of irradiated cells to support the replication of Herpes simplex virus. The target molecule has been shown to be DNA and is centrally located

Mammalian cells have an absolute requirement for Mg++ and Ca++ in order to remain attached to artificial substrata. To test the effect of cell geometry on UV radiation sensitivity. Monolayer cultires were exposed to a Mg++ and Ca++ free UV transparent buffer solution. Cultures containing from 0% to 100% spherical cells were irradiated

Cultures containing 40% or more spherical cells were less sensitive to UV exposures by as much as a factor of five. The decrease in sensitivity was proportional to the percentage of spherical cells in cultures from 0% to 40%.

An experiment was conducted in which the UV dose to the surface of spherical cells was modified by 24%, 27%, and 44%. The results of this experiment showed that 27% less energy ultimately reached an DNA target in a spherical cell than in an umbonate cell. It was concluded that protoplasmic shielding of the centrally located target molecule was probably responsible for the decreased UV radiation sensitivity of spherical cells


Biology | Cell and Developmental Biology | Cell Biology | Life Sciences