Chapter 6 - Targeting biofilms in chronic respiratory infections using drug delivery systems

Abstract

Bacterial biofilm infections caused by Pseudomonas aeruginosa is one of the main reasons contributing to the morbidity and mortality in patients with lung infections such as cystic fibrosis and pneumonia. Owing to the tolerance of bacterial biofilm to virtually most antibiotics, the eradication of biofilm remains a challenging task. P. aeruginosa biofilms possess various resistance mechanisms such as activated efflux pump, antibiotic-inactivating enzymes, and the presence of heterogeneous cell populations with different metabolic requirements (i.e., fast growing or dormant). It is commonly accepted that once bacterial biofilm infection has been established, it is hard to achieve complete eradication of the biofilm. In many chronic lung infections, biofilms are recurrent and could only be controlled with continuous aggressive antibiotic therapies. Therefore developments of novel drug formulations are crucial to improve efficacy of P. aeruginosa biofilm in the lung. Various novel formulations have been discovered in the recent years, which include antimicrobial peptides, bacteriophages and nanoparticles, and antibiotics. This chapter highlights the efficacy of novel compounds as antiplanktonic agent, antibiofilm agent, and antiquorum sensing agent to treat P. aeruginosa biofilm in the lungs.