Transgenic and gene-targeted mice as models for chronic obstructive pulmonary disease

Animal models play an important role in the understanding of the pathogenesis of chronic obstructive pulmonary disease (COPD). The applicability of findings to human COPD depends upon several factors, including the disease model, and similarities in mouse structure and function between species. There are many examples in the literature of transgenic mice that have contributed to the understanding of COPD. Several studies demonstrate the complexity of inflammatory networks and how unexpected findings in animal models have led to the search for new potential mediators in human disease. Gene-targeting studies into alpha(1)-antitrypsin (alpha(1)-AT) and emphysema in mice have demonstrated that the genetic locus for alpha(1)-AT in mice is very complex and that the loss of one gene is lethal in embryo lung development. This underlines the differences between mice and humans that limit the ability to translate between systems in some instances. Gene targeting has also highlighted complex roles for transforming growth factor-beta in COPD and has been used to determine important molecules and pathways in COPD. Both transgenic and gene-targeted models suffer limitations and their applicability to human chronic obstructive pulmonary disease may be dependant on several factors, some of which are still being learnt. The more that is known about similarities and differences, the better the knowledge will be that is gained to develop for chronic obstructive pulmonary disease.