Histological change of infiltrating inflammatory cells in sun-exposed and-unexposed skin / 中华皮肤科杂志

ABSTRACT

Objective To investigate the role of infiltrating inflammatory cells in photoaging process by comparing the type and number of these cells in sun-exposed and-unexposed skin.Methods The expression of CD3,CD45RO and CD68 were detected by immunohistochemieal staining in 46 paraffin-embeded skin samples from the extensor forearms(sun-exposed)and upper-inner arms(sun-unexposed) of 23 healthy female volunteers.The number of positive cells in sun-exposed and -unexposed sites was counted and statistically tested by paired samples t test,and Pearson correlation analysis was performed to assess the relationship between the number of positive cells and age of these volunteers.Results The number of cells positive for CD3,CD45RO and CD68 per square millimetre in sun-exposed skin was significantly higher than that in sun-unexposed skin(48.91±13.173 vs.40.61±11.571,46.83±12.915 vs.38.00±10.109,85.43±22.346 vs.73.48±16.208,respectively,P<0.01 or 0.05).The number of cells positive for CD3 and CD45RO increased significantly with age (r=0.557,0.555,respectively,both P<0.01) in the sun-exposed skin but not in sun-unexposed skin,and the number of CD68-positive cells was uncorrelated with age in either sunexposed or -unexposed skin.Conclusion T lymphocytes and macrophages may play a role in the process of photoaging.