Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa are major causes of hospital-acquired infections and sepsis. Due to increasing antibiotic resistance, new treatments are needed. Mesenchymal stem cells (MSCs) have antimicrobial effects, which can be enhanced by preconditioning with antibiotics. This study investigated using antibiotics to strengthen MSCs against MRSA and P. aeruginosa. MSCs were preconditioned with linezolid, vancomycin, meropenem, or cephalosporin. Optimal antibiotic concentrations were determined by assessing MSC survival. Antimicrobial effects were measured by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and antimicrobial peptide (AMP) gene expression. Optimal antibiotic concentrations for preconditioning MSCs without reducing viability were 1 μg/mL for linezolid, meropenem, and cephalosporin and 2 μg/mL for vancomycin. In MIC assays, MSCs preconditioned with linezolid, vancomycin, meropenem, or cephalosporin inhibited MRSA or P. aeruginosa growth at lower concentrations than non-preconditioned MSCs (p ≤ 0.001). In MBC assays, preconditioned MSCs showed enhanced bacterial clearance compared to non-preconditioned MSCs, especially when linezolid and vancomycin were used against MRSA (p ≤ 0.05). Preconditioned MSCs showed increased expression of genes encoding the antimicrobial peptide genes hepcidin and LL-37 compared to non-preconditioned MSCs. The highest hepcidin expression was seen with linezolid and vancomycin preconditioning (p ≤ 0.001). The highest LL-37 expression was with linezolid preconditioning (p ≤ 0.001). MSCs' preconditioning with linezolid, vancomycin, meropenem, or cephalosporin at optimal concentrations enhances their antimicrobial effects against MRSA and P. aeruginosa without compromising viability. This suggests preconditioned MSCs could be an effective adjuvant treatment for antibiotic-resistant infections. The mechanism may involve upregulation of AMP genes.
- MeSH
- antibakteriální látky farmakologie terapeutické užití MeSH
- antimikrobiální peptidy MeSH
- cefalosporiny farmakologie MeSH
- hepcidiny farmakologie terapeutické užití MeSH
- lidé MeSH
- linezolid farmakologie terapeutické užití MeSH
- meropenem farmakologie terapeutické užití MeSH
- methicilin rezistentní Staphylococcus aureus * MeSH
- mezenchymální kmenové buňky * MeSH
- mikrobiální testy citlivosti MeSH
- Pseudomonas aeruginosa genetika MeSH
- stafylokokové infekce * mikrobiologie MeSH
- vankomycin MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Chronic infections caused by Pseudomonas aeruginosa (P. aeruginosa) isolates are mainly related to resistance to antimicrobials and the production of certain virulence factors. The purpose of this study was twofold: to investigate the prevalence of virulence genes and to study the relationship between biofilm formation/alginate production/antibiotic resistance and the presence of genes associated with biofilm, alginate, flagella and exotoxin A in clinical isolates of P. aeruginosa. Microtiter plate biofilm assay and Carbazole method were used to examine the biofilm formation and alginate production ability of the isolates, respectively. The genes, ppyR, pslA, pelA (biofilm formation), algD, algU, algL (alginate production), fliC (flagella) and exoA (exotoxin A) were detected by PCR. Biofilm formation as well as alginate production ability was found in 47.1% of the clinical isolates. Based on PCR data, the frequency distribution of the genes in the clinical isolates was as follows: ppyR (99%), pslA (83.7%), pelA (45.2%), algU (90.4%), algL (73.1%), algD (87.5%), exoA (84.6%) and fliC (70.2%). Biofilm formation ability of the isolates was significantly correlated with the presence of the genes, pelA and fliC (statistically significant). In addition, 58.65% of the isolates were resistant to three or more different classes of antibiotics.
- MeSH
- algináty * MeSH
- bakteriální léková rezistence * MeSH
- bakteriální proteiny MeSH
- biofilmy MeSH
- elektroforéza metody využití MeSH
- faktory virulence * MeSH
- infekce spojené se zdravotní péčí MeSH
- lidé MeSH
- mnohočetná léková rezistence MeSH
- polymerázová řetězová reakce MeSH
- Pseudomonas aeruginosa * izolace a purifikace účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- vysokoškolské kvalifikační práce MeSH