To facilitate the investigation of the complex process that leads to h
ealing of a human skin wound we developed standardized and repeatable
in vitro models for both incisional and burn wounds. Wounds with a sta
ndardized area and depth were created in normal human skin biopsies wh
ich were then incubated in vitro. It was shown, by cultivation, that b
oth dermal and epidermal cells maintained their viability during a 14-
day in vitro incubation if exposed to at least 2% fetal calf serum. By
incubating in 10% serum, the skin samples were stimulated to complete
ly re-epithelialize the wounded area. Because a large number of standa
rdized wounds can be obtained from each donor, the re-epithelializatio
n process can be studied histologically and immunohistochemically at s
everal adjacent time points. The ability to keep the cells in the woun
d area viable without stimulating healing by incubating the wounds in
suboptimal serum concentrations implies a way of studying the stimulat
ory effects of different agents, such as growth factors, on the wound
healing process. There were some marked discrepancies in the healing p
rocess between the incisional and burn wounds which resemble the in vi
vo situation, indicating that the in vitro models could be used to mor
e closely study differences between healing in different types of woun
ds. Our findings suggest that in vitro tissue culture can be of great
value in attempting to better understand the complex process of wound
healing in human skin. (C) 1998 Wiley-Liss, Inc.