Immunomodulatory and Anti-inflammatory Activity in Vitro and in Vivo of a Novel Antimicrobial Candidate.

The synthetic antimicrobial peptide SET-M33 has strong activity against bacterial infections caused by Gram-negative bacteria. It is currently in preclinical development as a new drug to treat lung infections caused by Gram-negative bacteria. Here we report its strong anti-inflammatory activity in terms of reduced expression of a number of cytokines, enzymes, and signal transduction factors involved in inflammation triggered by LPS from Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli Sixteen cytokines and other major agents involved in inflammation were analyzed in macrophages and bronchial cells after stimulation with LPS and incubation with SET-M33.

In vitro and in vivo efficacy, toxicity, bio-distribution and resistance selection of a novel antibacterial drug candidate.

A synthetic antimicrobial peptide was identified as a possible candidate for the development of a new antibacterial drug. The peptide, SET-M33L, showed a MIC90 below 1.5 μM and 3 μM for Pseudomonas aeruginosa and Klebsiella pneumoniae, respectively.

The development of antimicrobial peptides as new antibacterial drugs.

The increasing frequency of multidrug-resistant bacteria and a recent slowing in the development of new antimicrobial agents place mankind in a state of emergency with regard to the threat of new bacterial infections. Antibacterial peptides (AMPs) are considered an important class of molecules to develop against bacteria. AMPs have been known for many years but very few have yet been extensively used in clinical practice, mainly because of their general toxicity and manufacturing cost.