Growth and adherence of xeroderma pigmentosum keratinocytes in vitro

Xeroderma pigmentosum (XP) is a rare autosomal recessive disease in which cells are unable to repair ultraviolet light-induced DNA defects. Keratinocytes were obtained from the right medial leg of a 16-year-old girl with XP. Two donor sites were harvested: One was an obviously damaged area; the second was an area that had been harvested five years previously and now grossly appeared normal. The cells were plated on untreated plastic tissue culture dishes. All XP keratinocytes grew much faster and spread more rapidly than non-XP controls. There was a 1.5 to 2.5 times increase in the growth rate of XP cells from the obviously damaged area over XP cells from the normal-appearing area. The XP keratinocytes also showed an in vitro expressed alteration in adhesion compared with control keratinocytes, which appears to be independent of the cell growth rate.