Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395

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  • Article
    Three-Dimensional Culture Enhances the Antimicrobial Activity of Mesenchymal Stem Cells against Shiga Toxin-Producing Escherichia Coli O157:H7 in Vitro
    (Oxford Univ Press, 2026) Fidan, Özkan; Türkyılmaz, Süheyla; Bicer, Mesude; Öztürk, Esengül; Sener, Fatma
    Aims This study examines the in vitro antibacterial activity of palatal adipose tissue-derived mesenchymal stem cells (PAT-MSCs) and the expression of antimicrobial peptide LL-37, with a particular focus on the effect of three-dimensional (3D) nanofibrillar cellulose-based hydrogel against Shiga toxin-producing Escherichia coli (STEC) harboring stx1 and/or stx2 genes isolated from mastitis milk in Turkey.Methods and results The antibacterial activity of conventionally cultured PAT-MSCs and 3D-cultured PAT-MSCs (PAT-MSCs-3D) was evaluated against STEC isolates and Escherichia coli ATCC 35150 using quantitative colony-forming unit (CFU) assay. The expression levels of antimicrobial peptide (AMP)-encoding genes were evaluated by quantitative real-time PCR, and AMP production was further validated by immunocytochemical staining. The results indicated that PAT-MSCs-3D exhibited significantly enhanced antibacterial efficacy, resulting in marked bacterial inhibition of all tested STEC strains, with bacterial reductions reaching up to 6-7 log under specific experimental conditions. Molecular and immunocytochemical analyses demonstrated increased expression of the antimicrobial peptide LL-37 in PAT-MSCs-3D compared to 2D cultures.Conclusions Our results show that culturing PAT-MSCs in 3D conditions leads to a significant enhancement in their antimicrobial properties, which could be linked to the upregulation of LL-37.
  • Article
    Cellulose-Based Hydrogel Matrix Enhances Antimicrobial and Biofilm-Inhibitory Responses of Palatal Mesenchymal Stem Cells
    (Springer Heidelberg, 2026) Fidan, Özkan; Bicer, Mesude; Öztürk, Esengül; Sener, Fatma
    Mesenchymal stem cells (MSCs) have emerged as promising alternatives to fight drug-resistant bacterial infections. This study investigates the antibacterial activity of palatal adipose tissue-derived MSCs (PMSCs), particularly when cultured within a 3D nanofibrillar cellulose hydrogel, against four clinically relevant pathogens: Pseudomonas aeruginosa K6, Staphylococcus aureus ATCC 25,923, Bacillus cereus K9 and Escherichia coli O157:H7. This study showed that both PMSCs alone and PMSCs in 3D cellulose-based hydrogel effectively inhibited the growth of bacterial burden. Notably, PMSCs cultured in the 3D system demonstrated an excellent effect, reducing bacterial burden by up to 14 log in E. coli and 12 log in P. aeruginosa K6 at a 120 & micro;L inoculum after 2 h of incubation. RT-PCR and immunocytochemical analyses found out a remarkable upregulation of the Cathelicidin (LL-37) in PMSCs 3D cultures compared to PMSCs. Furthermore, 3D cellulose-based hydrogel exhibited a significant biofilm-inhibitory effect, reaching a 57.65% reduction. The results demonstrated the importance of 3D cellulose-based hydrogel for treating antibiotic-resistant infections. PMSC therapy based on 3D hydrogel may therefore be offered as more effective antimicrobial agent to overcome drug-resistant bacterial infections.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 5
    Can Mesenchymal Stem/Stromal Cells and Their Secretomes Combat Bacterial Persisters
    (Springer, 2023-08-12) Bicer, Mesude; Fidan, Ozkan
    The increasing number of life-threatening infections caused by persister bacteria is associated with various issues, including antimicrobial resistance and biofilm formation. Infections due to persister cells are often difficult to suppress without the use of last-resort antibiotics. Throughout the world, bacterial persistence and resistance create an unmet clinical demand for the exploration of newly introduced therapeutic approaches. Mesenchymal stem / stromal cells (MSCs) have an antimicrobial activity to protect against bacterial infections, including those caused by bacterial persisters. MSCs have substantial potential to secrete antimicrobial peptides (AMPs), including cathelicidin, beta-defensins, lipocalin-2, hepcidin, indoleamine 2,3-dioxygenase (IDO), cysteine proteases, and inducible nitric oxide synthases (iNOS). MSCs possess the potential to contribute to innate immunity by regulating the immune response. Recently, MSCs and their secreted components have been reported to improve antimicrobial activity. Bactericidal activity by MSCs and their secretomes has been shown to be mediated in part by the secretion of AMPs. Even though they were discovered more than 80 years ago, therapeutic options for persisters are restricted, and there is an urgent need for alternative treatment regimens. Hence, this review intends to critically assess the current literature on the effects of MSCs and their secretomes on persister bacteria. MSCs and their secretome-based therapies could be preferred as an up-and-coming approach to reinforce the antimicrobial efficiency in persister infections.