Aptamers as Novel Binding Molecules on an Antimicrobial Peptide-Armored Composite Hydrogel Wound Dressing for Specific Removal and Efficient Eradication of Pseudomonas aeruginosa

Abstract

Here we present for the first time a potential wound dressing material implementing aptamers as binding entities to remove pathogenic cells from newly contaminated surfaces of wound matrix-mimicking collagen gels. The model pathogen in this study was the Gram-negative opportunistic bacterium Pseudomonas aeruginosa, which represents a considerable health threat in hospital environments as a cause of severe infections of burn or post-surgery wounds. A two-layered hydrogel composite material was constructed based on an established eight-membered focused anti-P. aeruginosa polyclonal aptamer library, which was chemically crosslinked to the material surface to form a trapping zone for efficient binding of the pathogen. A drug-loaded zone of the composite released the C14R antimicrobial peptide to deliver it directly to the bound pathogenic cells. We demonstrate that this material combining aptamer-mediated affinity and peptide-dependent pathogen eradication can quantitatively remove bacterial cells from the “wound” surface, and we show that the surface-trapped bacteria are completely killed. The drug delivery function of the composite thus represents an extra safeguarding property and thus probably one of the most important additional advances of a next-generation or smart wound dressing ensuring the complete removal and/or eradication of the pathogen of a freshly infected wound.

Natural and Synthetic Polymers for Biomedical and Environmental Applications

“…Alginate dressings, composed of seaweed-derived alginic acid, absorb excess exudate from the wound. This maintains a moist environment and helps prevent bacterial proliferation in overly damp conditions [ 61 ].…”

“…This is vital for ensuring adequate blood supply to the healing tissue. Polymers like pectin and chitosan, which can be used in wound dressings, create a protective barrier over the wound, allowing for oxygen and nutrient exchange (Figures 3 and 5) [61]. This can help prevent external contaminants from entering the wound.…”

Diagnosis and Therapeutic Strategies Based on Nucleic Acid Aptamers Selected against Pseudomonas aeruginosa: The Challenge of Cystic Fibrosis

“…Additionally, the authors developed a simulated postsurgical wound system based on 12-well plates covered with rat tail collagen in which the collagen matrix was "infected" with P. aeruginosa and subsequently treated with "smart wound dressing", demonstrating in vitro both the bacterial capture mediated by aptamers and the bactericidal effect of C14R on the bacteria located in the region covered by the "bandage". [113]…”

“…(2023) used the ABCs system to design a “smart wound dressing” composed of two regions, one that stored an antimicrobial peptide with antimicrobial activity against CR variants of P. aeruginosa (C14R) and the other with the eight best aptamers of the R16 polyclonal library [85] immobilized on its surface; based on the concept of “capture‐and‐kill”, the hydrogel was capable of releasing C14R onto P. aeruginosa immobilized on its surface. Additionally, the authors developed a simulated postsurgical wound system based on 12‐well plates covered with rat tail collagen in which the collagen matrix was “infected” with P. aeruginosa and subsequently treated with “smart wound dressing”, demonstrating in vitro both the bacterial capture mediated by aptamers and the bactericidal effect of C14R on the bacteria located in the region covered by the “bandage” [113] …”

Pore-forming peptide C14R exhibits potent antifungal activity against clinical isolates of Candida albicans and Candida auris

“…These small cationic and amphipathic molecules, typically consisting of less than 50 amino acids, form part of the primary line of defense against pathogens of many organism ( Matejuk et al., 2010 ). Among these, C14R, a designed analog derived from peptide BP100 isolated from bee venom, has previously demonstrated its antimicrobial activity against a wide range of resistant bacteria, including both Gram-positive and Gram-negative ( Badosa et al., 2013 ; Torcato et al., 2013 ; Bodenberger et al., 2018 ; Kraemer et al., 2023 ). Recently, this membrane-active peptide was intensively characterized for its great antibacterial activity towards pathogenic Pseudomonas aeruginosa with characteristic pore forming capability hence its amphipathic structure.…”