This section focuses on the application of differential display in gaining insight into cDNAs upregulated in association with a disease state by using direct in vivo samples. Although the majority of differential display studies have focused on in vitro models, a growing number of laboratories have used the technique on in vivo models of tissues with success (1 –3 ). With in vitro systems concerns might be raised about potential artifacts related to models using tissue culture conditions, transformed cells, single-cell populations, and exogenous stimulants that may not mimic pathophysiologic conditions. The advantage of using diseased tissues directly is that the pathophysiologic conditions including the multiple interacting cells are preserved directly in the regulatory environment in which the disease arises.
