Natural defense against disease

A complex and finely tuned system of regulation and function of intestinal antimicrobial peptides contributes to the maintenance and balance of commensal flora in the healthy gut. Disruption of this critical balance could lead to gastrointestinal infection and disease.
The skin's first line of defense against invasion by microbial agents is the stratum corneum, a nonviable, desiccated layer of the epidermis. This physical barrier is however susceptible to injuries that allows the entry of opportunistic microbial agents into the skin. The innate immune system can immediately respond to this intrusion by helping to prevent further invasion.

Decreased levels of defensins characterize diseases like asthma and chronic obstructive pulmonary disease (COPD) whereas increased levels of defensins have been observed in cystic fibrosis, diffuse panbroncheolitis, idiopathic pulmonary fibrosis, acute respiratory distress syndrome and lung transplants.
