Porcine fallopian tube stem cells exosomes and hyperbranced polymerdots with laser treatment therapy for nude mice wound healing

Summary: Abstract Body: Eepithelial-to-mesenchymal transition(EMT), where epithelial cells acquire mesenchymal characteristics, is crucial in wound healing. Porcine Fallopian Tube Stem Cell(PFTSC)-derived exosomes and nanomaterial polymer dots(PDs) are known to promote EMT. Meanwhile, picosecond 755 nm laser-induced optical breakdown(LIOB), initially used in cosmetic treatments, has shown promise in wound repair and photodamage recovery. Fifteen mice were assigned to five groups: (1)control, (2)exosomes, (3)exosomes + PDs, (4)laser + exosomes, and (5)laser + exosomes + PDs (combination group). Wounds were created on the mice's backs and analyzed using Image-J. Biomarkers such as ERK1/2, VEGF, EGF, CD31, collagen1/3, and pro-collagen 1/3 were assessed via ELISA, immunostaining, and Masson trichrome staining. Exosomes enhanced ERK1/2 and EGF levels, with PDs further increasing EGF expression (1.6% vs. 0.5% in controls, p<0.01). Laser treatment delayed ERK expression and slowed early proliferative phase wound healing. However, the combination group exhibited superior angiogenesis (VEGF: 18% vs. 4%, p<0.0001; CD31: 17% vs. 5%, p<0.05), improved skin barrier restoration (filaggrin: 11% vs. 6%, p<0.05), and faster wound closure (wound size: 13% vs. 33%, p<0.0001). The combination also demonstrated higher collagen quality (pro-collagen 3 and collagen 1) and dense, organized scar tissue (MT staining: 39% vs. 19%, p<0.0001). Vimentin and E-cadherin co-expression was observed during the proliferative phase in the combination group. We suggest that the combination of exosomes, PDs, and laser therapy effectively induces partial EMT, accelerates wound re-epithelialization, enhances angiogenesis, and improves scar quality. While laser therapy promotes collagen deposition and angiogenesis, it may impede early proliferative phase healing. This combination strategy offers a promising therapeutic approach for wound repair and regeneration. Chang Cheng Chang^{1, 2}, Tzong-Yuan Juang³, Yen Jen Wang⁴, Yi-Hsuan Tu² 1. China Medical University Hospital, Taichung, Taichung City, Taiwan. 2. China Medical University College of Medicine, Taichung City, Taichung City, Taiwan. 3. China Medical University, Taichung, Taichung City, Taiwan. 4. Mackay Memorial Hospital, Taipei City, Taipei City, Taiwan. Stem Cell Biology, Tissue Regeneration and Wound Healing