Jefferson Researchers First To Create Genetically Engineered Mouse To Study ...( switch resulting in up to a 30-fol...)

Drs. Uitto and Bernstein were able to detect this increase in elastin as early as 24 to 48 hours after irradiating the mice. "Our transgenic mouse is a huge advance because of the rapidity and sensitivity with which we are able to measure results," said Dr. Bernstein. "Other mouse models have taken at least six months to a year to show effects of photodamage caused by irradiation."

The researchers were also able to apply sunscreens and related compounds to the skin of the mice and found a correlative relationship between the sun protection factor (SPF) and the degree to which elastin promoter activity was reduced. "The higher the SPF we applied to the skin of the mice, the lower the percentage of elastin promoter activity, or photodamage, that we measured,? explained Dr. Uitto. ?We saw the highest reduction in photodamage when we applied compounds that protected against UVB and UVA rays."

"The transgenic model adds a molecular component to the evaluation of sunscreen efficacy," added Dr. Gasparro. "Prior to this look at molecular assay, efficacy was based solely on physiological responses. Molecular assays are important because they can provide information about the possible fate of a cell."

The transgenic mice do not have any physical differences that would visually distinguish them from other mice, and they can be bred since they pass along the human elastin promoter linked to the CAT gene to their young. Cell cultures can also be made from tissue biopsies of their skin, which has allowed the researchers to examine the molecular changes caused by photodamage.

"This model has given us a clearer picture of what happens to skin when exposed to different forms of ultraviolet light," said Dr. Bernstein. "Our research has p
'"/>

Contact: Maria Cerceo or Phyllis Fisher
Maria.Cerceo@mail.tju.edu
215-955-6300
Thomas Jefferson University
17-Feb-1998