Akram AR, Avlonitis N, Vendrell M, Chankeshwara S, McDonald N, Aslam T, Scholefield E, Walsh T, Haslett C, Bradley M, Dhaliwal K. T4 Optically detectable antimicrobial peptides enable the immediate detection of bacteria and fungi in the lung. Thorax 2015;70:A2–A3. doi:10.1136/thoraxjnl-2015-207770.4

Corrections have been made to the ‘Results’ section of this abstract. The changes are in bold.

Results

AMP-1 demonstrates bacterial binding affinity in a concentration dependent manner and labels a diverse panel of bacteria, including a panel consisting of >70% of ventilator-associated pneumonia causing organisms and the pathogenic fungi Aspergillus fumigatus. AMP-1 demonstrates significantly higher fluorescence over isomolar linear equivalents for E. coli, K. pneumoniae, P. aeruginosa, MSSA, A. baumannii and S. pneumoniae (all p<0.01), is selective for bacteria over mammalian cells and has improved chemical stability over the linear equivalent when incubated with bronchoaoveolar lavage from patients with acute respiratory distress syndrome. Furthermore, AMP-1 can label E. coli, K. pneumoniae, P. aeruginosa and MSSA in situ in an ex vivo ovine model when instilled endobronchially and imaged with FCFM (p<0.01 when compared to control segments). AMP-2 can selectively label gram-negative bacteria, but not gram-positive bacteria in vitro and remains selective for gram-negative bacteria over mammalian cells. In the ex-vivo model AMP-2 selectively labels the gram-negative bacterial segments (P. aeruginosa, K. pneumonia and E. coli) over the gram-positive MSSA, MRSA and S. pneumoniae or control pulmonary segments (all p<0.05).