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Xu H, Zhang Y, Ma J, Miao H, Chen S, Gao S, Rong H, Deng L, Zhang J, Dong A, Li S. Preparation and characterization of a polyurethane-based sponge wound dressing with a superhydrophobic layer and an antimicrobial adherent hydrogel layer. Acta Biomater 2024; 181:235-248. [PMID: 38692469 DOI: 10.1016/j.actbio.2024.04.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 04/21/2024] [Accepted: 04/25/2024] [Indexed: 05/03/2024]
Abstract
Bacterial infection poses a significant impediment in wound healing, necessitating the development of dressings with intrinsic antimicrobial properties. In this study, a multilayered wound dressing (STPU@MTAI2/AM1) was reported, comprising a surface-superhydrophobic treated polyurethane (STPU) sponge scaffold coupled with an antimicrobial hydrogel. A superhydrophobic protective outer layer was established on the hydrophilic PU sponge through the application of fluorinated zinc oxide nanoparticles (F-ZnO NPs), thereby resistance to environmental contamination and bacterial invasion. The adhesive and antimicrobial inner layer was an attached hydrogel (MTAI2/AM1) synthesized through the copolymerization of N-[2-(methacryloyloxy)ethyl]-N, N, N-trimethylammonium iodide and acrylamide, exhibits potent adherence to dermal surfaces and broad-spectrum antimicrobial actions against resilient bacterial strains and biofilm formation. STPU@MTAI2/AM1 maintained breathability and flexibility, ensuring comfort and conformity to the wound site. Biocompatibility of the multilayered dressing was demonstrated through hemocompatibility and cytocompatibility studies. The multilayered wound dressing has demonstrated the ability to promote wound healing when addressing MRSA-infected wounds. The hydrogel layer demonstrates no secondary damage when peeled off compared to commercial polyurethane sponge dressing. The STPU@MTAI2/AM1-treated wounds were nearly completely healed by day 14, with an average wound area of 12.2 ± 4.3 %, significantly lower than other groups. Furthermore, the expression of CD31 was significantly higher in the STPU@MTAI2/AM1 group compared to other groups, promoting angiogenesis in the wound and thereby contributing to wound healing. Therefore, the prepared multilayered wound dressing presents a promising therapeutic candidate for the management of infected wounds. STATEMENT OF SIGNIFICANCE: Healing of chronic wounds requires avoidance of biofouling and bacterial infection. However developing a wound dressing which is both anti-biofouling and antimicrobial is a challenge. A multilayered wound dressing with multifunction was developed. Its outer layer was designed to be superhydrophobic and thus anti-biofouling, and its inner layer was broad-spectrum antimicrobial and could inhibit biofilm formation. The multilayered wound dressing with adhesive property could easily be removed from the wound surface preventing the cause of secondary damage. The multilayered wound dressing has demonstrated good abilities to promote MRSA-infected wound healing and presents a viable treatment for MRSA-infected wound.
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Affiliation(s)
- Hang Xu
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China
| | - Yufeng Zhang
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China
| | - Jinzhu Ma
- NMPA Key Laboratory for Quality Evaluation of Non-active Implant Devices, Tianjin, 300384, China
| | - Hui Miao
- NMPA Key Laboratory for Quality Evaluation of Non-active Implant Devices, Tianjin, 300384, China
| | - Shangliang Chen
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China
| | - Shangdong Gao
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300350, China
| | - Hui Rong
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China
| | - Liandong Deng
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China
| | - Jianhua Zhang
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China; Tianjin Key Laboratory of Membrane Science and Desalination Technology, Tianjin University, Tianjin 300350, China
| | - Anjie Dong
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China.
| | - Shuangyang Li
- Department of Polymer Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China; Frontiers Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China.
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Wiegand C, Fink S, Mogrovejo DC, Ruhlandt M, Wiencke V, Eberlein T, Brill FHH, Tittelbach J. A standardized wound infection model for antimicrobial testing of wound dressings in vitro. Int Wound J 2024; 21:e14811. [PMID: 38477866 DOI: 10.1111/iwj.14811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 02/07/2024] [Accepted: 02/09/2024] [Indexed: 03/14/2024] Open
Abstract
To investigate the effectiveness of antimicrobial agents against wound infections, experiments using either 2D cultures with planktonic microorganisms or animal infection models are frequently carried out. However, the transferability of the results to human skin is limited by the lack of complexity of the 2D models or by the poor translation of the results from animal models. Hence, there is a need for wound infection models capable of assessing antimicrobial agents. In this study, an easily standardized wound infection model was established. This model consists of a mechanically wounded human skin model on a collagen matrix infected with various clinically relevant bacteria. Infection of the model led to recognition of the pathogens and induction of an inflammatory response. The untreated infection spread over time, causing significant tissue damage. By applying an antimicrobial-releasing wound dressing, the bacterial load could be reduced and the success of the treatment could be further measured by a decrease in the inflammatory reaction. In conclusion, this wound infection model can be used to evaluate new antimicrobial therapeutics as well as to study host-pathogen interactions.
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Affiliation(s)
- Cornelia Wiegand
- Department of Dermatology, Jena University Hospital, Jena, Germany
| | - Sarah Fink
- Department of Dermatology, Jena University Hospital, Jena, Germany
| | - Diana C Mogrovejo
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, Hamburg, Germany
| | - Marina Ruhlandt
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, Hamburg, Germany
| | - Vanessa Wiencke
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, Hamburg, Germany
| | | | - Florian H H Brill
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, Hamburg, Germany
| | - Jörg Tittelbach
- Department of Dermatology, Jena University Hospital, Jena, Germany
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Dittmer M, Brill FHH, Kampe A, Geffken M, Rembe JD, Moll R, Alio I, Streit WR, Debus ES, Smeets R, Stuermer EK. Quantitative Insights and Visualization of Antimicrobial Tolerance in Mixed-Species Biofilms. Biomedicines 2023; 11:2640. [PMID: 37893014 PMCID: PMC10604264 DOI: 10.3390/biomedicines11102640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/20/2023] [Accepted: 09/21/2023] [Indexed: 10/29/2023] Open
Abstract
Biofilms are a major problem in hard-to-heal wounds. Moreover, they are composed of different species and are often tolerant to antimicrobial agents. At the same time, interspecific synergy and/or competition occurs when some bacterial species clash. For this reason, the tolerance of two dual-species wound biofilm models of Pseudomonas aeruginosa and Staphylococcus aureus or Enterococcus faecium against antimicrobials and antimicrobial dressings were analyzed quantitatively and by confocal laser scanning microscopy (CLSM). The results were compared to findings with planktonic bacteria. Octenidine-dihydrochloride/phenoxyethanol and polyhexamethylene biguanide (PHMB) irrigation solutions showed a significant, albeit delayed reduction in biofilm bacteria, while the PHMB dressing was not able to induce this effect. However, the cadexomer-iodine dressing caused a sustained reduction in and killed almost all bacteria down to 102 cfu/mL within 6 days compared to the control (1010 cfu/mL). By means of CLSM in untreated human biofilm models, it became evident that P. aeruginosa dominates over E. faecium and S. aureus. Additionally, P. aeruginosa appeared as a vast layer at the bottom of the samples, while S. aureus formed grape-like clusters. In the second model, the distribution was even clearer. Only a few E. faecium were visible, in contrast to the vast layer of P. aeruginosa. It seems that the different species avoid each other and seek their respective niches. These mixed-species biofilm models showed that efficacy and tolerance to antimicrobial substances are nearly species-independent. Their frequent application appears to be important. The bacterial wound biofilm remains a challenge in treatment and requires new, combined therapy options.
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Affiliation(s)
- Mandy Dittmer
- Department of Vascular Medicine, Translational Research, University Heart Center, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Florian H H Brill
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, 22339 Hamburg, Germany
| | - Andreas Kampe
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, 22339 Hamburg, Germany
| | - Maria Geffken
- Institute for Transfusion Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Julian-Dario Rembe
- Department of Vascular and Endovascular Surgery, Heinrich-Heine-University of Düsseldorf, 40225 Düsseldorf, Germany
| | - Raphael Moll
- Department of Microbiology and Biotechnology, University Hamburg, 20148 Hamburg, Germany
| | - Ifey Alio
- Department of Microbiology and Biotechnology, University Hamburg, 20148 Hamburg, Germany
| | - Wolfgang R Streit
- Department of Microbiology and Biotechnology, University Hamburg, 20148 Hamburg, Germany
| | - Eike Sebastian Debus
- Department of Vascular Medicine, Translational Research, University Heart Center, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Ralf Smeets
- Department of Oral and Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Ewa Klara Stuermer
- Department of Vascular Medicine, Translational Research, University Heart Center, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
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Song L, Yang H, Meng X, Su R, Cheng S, Wang H, Bai X, Guo D, Lü X, Xia X, Shi C. Inhibitory Effects of Trans-Cinnamaldehyde Against Pseudomonas aeruginosa Biofilm Formation. Foodborne Pathog Dis 2023; 20:47-58. [PMID: 36779942 DOI: 10.1089/fpd.2022.0073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Pseudomonas aeruginosa biofilm formation has been considered to be an important determinant of its pathogenicity in most infections. The antibiofilm activity of trans-cinnamaldehyde (TC) against P. aeruginosa was investigated in this study. Results demonstrated that the minimum inhibitory concentration (MIC) of TC against P. aeruginosa was 0.8 mg/mL, and subinhibitory concentrations (SICs) was 0.2 mg/mL and below. Crystal violet staining showed that TC at 0.05-0.2 mg/mL reduced biofilm biomass in 48 h in a concentration-dependent mode. The formation area of TC-treated biofilms was significantly declined (p < 0.01) on the glass slides observed by light microscopy. Field-emission scanning electron microscopy further demonstrated that TC destroyed the biofilm morphology and structure. Confocal laser scanning microscopic observed the dispersion of biofilms and the reduction of exopolysaccharides after TC treatment stained with concanavalin A (Con-A)-fluorescein isothiocyanate conjugate and Hoechst 33258. Meanwhile, TC caused a significant decrease (p < 0.01) in the component of polysaccharides, proteins, and DNA in extracellular polymeric substance. The swimming and swarming motility and quorum sensing of P. aeruginosa was also found to be significantly inhibited (p < 0.01) by TC at SICs. Furthermore, SICs of TC repressed the several genes transcription associated with biofilm formation as determined by real-time quantitative polymerase chain reaction. Overall, our findings suggest that TC could be applied as natural and safe antibiofilm agent to inhibit the biofilm formation of P. aeruginosa.
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Affiliation(s)
- Luyi Song
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Hui Yang
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xinru Meng
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Ruiying Su
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Shuai Cheng
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Haoran Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xiangyang Bai
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Du Guo
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xin Lü
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xiaodong Xia
- School of Food Science and Technology, National Engineering Research Center of Seafood, Dalian Polytechnic University, Dalian, China
| | - Chao Shi
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
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Biofilms in Chronic Wound Infections: Innovative Antimicrobial Approaches Using the In Vitro Lubbock Chronic Wound Biofilm Model. Int J Mol Sci 2023; 24:ijms24021004. [PMID: 36674518 PMCID: PMC9862456 DOI: 10.3390/ijms24021004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/23/2022] [Accepted: 12/27/2022] [Indexed: 01/06/2023] Open
Abstract
Chronic wounds have harmful effects on both patients and healthcare systems. Wound chronicity is attributed to an impaired healing process due to several host and local factors that affect healing pathways. The resulting ulcers contain a wide variety of microorganisms that are mostly resistant to antimicrobials and possess the ability to form mono/poly-microbial biofilms. The search for new, effective and safe compounds to handle chronic wounds has come a long way throughout the history of medicine, which has included several studies and trials of conventional treatments. Treatments focus on fighting the microbial colonization that develops in the wound by multidrug resistant pathogens. The development of molecular medicine, especially in antibacterial agents, needs an in vitro model similar to the in vivo chronic wound environment to evaluate the efficacy of antimicrobial agents. The Lubbock chronic wound biofilm (LCWB) model is an in vitro model developed to mimic the pathogen colonization and the biofilm formation of a real chronic wound, and it is suitable to screen the antibacterial activity of innovative compounds. In this review, we focused on the characteristics of chronic wound biofilms and the contribution of the LCWB model both to the study of wound poly-microbial biofilms and as a model for novel treatment strategies.
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Development of an implantable three-dimensional model of a functional pathogenic multispecies biofilm to study infected wounds. Sci Rep 2022; 12:21846. [PMID: 36528648 PMCID: PMC9759537 DOI: 10.1038/s41598-022-25569-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Accepted: 12/01/2022] [Indexed: 12/23/2022] Open
Abstract
Chronic wounds cannot heal due to impairment of regeneration, mainly caused by the persistent infection of multispecies biofilms. Still, the effects of biofilm wound infection and its interaction with the host are not fully described. We aimed to study functional biofilms in physiological conditions in vitro, and their potential effects in health and regeneration in vivo. Therefore, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis were seeded in collagen-based scaffolds for dermal regeneration. After 24 h, scaffolds had bacterial loads depending on the initial inoculum, containing viable biofilms with antibiotic tolerance. Afterwards, scaffolds were implanted onto full skin wounds in mice, together with daily supervision and antibiotic treatment. Although all mice survived their health was affected, displaying fever and weight loss. After ten days, histomorphology of scaffolds showed high heterogeneity in samples and within groups. Wounds were strongly, mildly, or not infected according to colony forming units, and P. aeruginosa had higher identification frequency. Biofilm infection induced leucocyte infiltration and elevated interferon-γ and interleukin-10 in scaffolds, increase of size and weight of spleen and high systemic pro-calcitonin concentrations. This functional and implantable 3D biofilm model allows to study host response during infection, providing a useful tool for infected wounds therapy development.
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Besser M, Schaeler L, Plattfaut I, Brill FHH, Kampe A, Geffken M, Smeets R, Debus ES, Stuermer EK. Pulsed low-intensity laser treatment stimulates wound healing without enhancing biofilm development in vitro. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2022; 233:112504. [PMID: 35777177 DOI: 10.1016/j.jphotobiol.2022.112504] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 03/14/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
OBJECTIVES Treating infected or chronic wounds burdened with biofilms still is a major challenge in medical care. Healing-stimulating factors lose their efficacy due to bacterial degradation, and antimicrobial substances negatively affect dermal cells. Therefore, alternative treatment approaches like the pulsed low intensity laser therapy (LILT) require consideration. METHODS The effect of pulsed LILT (904 nm, in three frequencies) on relevant human cells of the wound healing process (fibroblasts (BJ), keratinocytes (HaCaT), endothelial cells (HMEC), monocytes (THP-1)) were investigated in in-vitro and ex-vivo wound models with respect to viability, proliferation and migration. Antimicrobial efficacy of the most efficient frequency in cell biological analyses of LILT (3200 Hz) was determined in a human biofilm model (lhBIOM). Quantification of bacterial load was evaluated by suspension method and qualitative visualization was performed by scanning electron microscopy (SEM). RESULTS Pulsed LILT at 904 nm at 3200 Hz ± 50% showed the most positive effects on metabolic activity and proliferation of human wound cells in vitro (after 72 h - BJ: BPT 0.97 ± 0.05 vs. 0.75 ± 0.04 (p = 0.0283); HaCaT: BPT 0.79 ± 0.04 vs. 0.59 ± 0.02 (p = 0.0106); HMEC: 0.74 ± 0.02 vs. 0.52 ± 0.04 (p = 0.009); THP-1: 0.58 ± 0.01 vs. 0.64 ± 0.01 (p > 0.05) and ex vivo. Interestingly, re-epithelialization was stimulated in a frequency-independent manner. The inhibition of metabolic activity after TNF-α application was abolished after laser treatment. No impact of LILT on monocytes was detected. Likewise, the tested LILT regimens showed no growth rate reducing effects on three bacterial strains (after 72 h - PA: -1.03%; SA: -0.02%; EF: -1,89%) and one fungal (-2.06%) biofilm producing species compared to the respective untreated control. Accordingly, no significant morphological changes of the biofilms were observed after LILT treatment in the SEM. CONCLUSIONS Frequent application of LILT (904 nm, 3200 Hz) seems to be beneficial for the metabolism of human dermal cells during wound healing. Considering this, the lack of disturbance of the behavior of the immune cells and no growth-inducing effect on bacteria and fungi in the biofilm can be assigned as rather positive. Based on this combined mode of action, LILT may be an option for hard to heal wounds infected with persistent biofilms.
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Affiliation(s)
- Manuela Besser
- Clinic for General, Visceral and Transplant Surgery, University Hospital Muenster, Germany
| | - Lukas Schaeler
- Institute of Virology and Microbiology, Faculty of Health, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Germany
| | - Isabell Plattfaut
- Institute of Virology and Microbiology, Faculty of Health, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Germany
| | - Florian H H Brill
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, Hamburg, Germany
| | - Andreas Kampe
- Dr. Brill + Partner GmbH, Institute for Hygiene and Microbiology, Hamburg, Germany
| | - Maria Geffken
- Institute for Transfusion Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ralf Smeets
- Department of Oral and Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf, Germany
| | - E Sebastian Debus
- Dpt. of Vascular Medicine, University Heart Center, University Medical Center Hamburg-Eppendorf (UKE), Germany
| | - Ewa K Stuermer
- Dpt. of Vascular Medicine, University Heart Center, University Medical Center Hamburg-Eppendorf (UKE), Germany.
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Antimicrobial Peptide L18R Displays a Modulating Action against Inter-Kingdom Biofilms in the Lubbock Chronic Wound Biofilm Model. Microorganisms 2021; 9:microorganisms9081779. [PMID: 34442858 PMCID: PMC8399358 DOI: 10.3390/microorganisms9081779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 01/22/2023] Open
Abstract
Chronic wound infections represent an important health problem due to the reduced response to antimicrobial treatment of the pathogens organized in structured biofilms. This study investigated the effects of the previously described antifungal peptide L18R against three representative wound pathogens: Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. The antimicrobial activity of L18R was evaluated (i) against single planktonic microbial populations; (ii) on single, dual, and triadic species of biofilms in both the early stage and mature stage; and (iii) in the polymicrobial Lubbock chronic wound biofilm (LCWB) model, mimicking spatial microbial colonization. This study used the evaluation of CFUs, biofilm biomass detection, and confocal and scanning electron microscopy analysis. L18R showed a significant antimicrobial activity against planktonic microorganisms and was able to differentially reduce the biomass of monomicrobial biofilms. No reduction of biomass was observed against the polymicrobial biofilm. In mature LCWB, L18R caused a moderate reduction in total CFU number, with a variable effect on the different microorganisms. Microscopy images confirmed a predominant presence of P.aeruginosa and a lower percentage of C. albicans cells. These findings suggest a modulating action of L18R and recommend further studies on its potential role in chronic wound management in association with conventional antibiotics or alternative treatments.
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