Human Umbilical Cord Mesenchymal Stromal Cell-Derived Extracellular Vesicles Induce Fetal Wound Healing Features Revealed by Single-Cell RNA Sequencing.

The potential of human umbilical cord mesenchymal stromal cell-derived extracellular vesicles (hucMSC-EVs) in wound healing is promising, yet a comprehensive understanding of how fibroblasts and keratinocytes respond to this treatment remains limited. This study utilizes single-cell RNA sequencing (scRNA-seq) to investigate the impact of hucMSC-EVs on the cutaneous wound microenvironment in mice. Through rigorous single-cell analyses, we unveil the emergence of hucMSC-EV-induced hematopoietic fibroblasts and MMP13+ fibroblasts. Notably, MMP13+ fibroblasts exhibit fetal-like expressions of MMP13, MMP9, and HAS1, accompanied by heightened migrasome activity. Activation of MMP13+ fibroblasts is orchestrated by a distinctive PIEZO1-calcium-HIF1α-VEGF-MMP13 pathway, validated through murine models and dermal fibroblast assays. Organotypic culture assays further affirm that these activated fibroblasts induce keratinocyte migration via MMP13-LRP1 interactions. This study significantly contributes to our understanding of fibroblast heterogeneities as well as intercellular interactions in wound healing and identifies hucMSC-EV-induced hematopoietic fibroblasts as potential targets for reprogramming. The therapeutic targets presented by these fibroblasts offer exciting prospects for advancing wound healing strategies.

Modified technique for robot-assisted laparoscopic infantile ureteral reimplantation for obstructive megaureter.

PURPOSE: To describe a novel modification of technique to improve efficacy of robot-assisted laparoscopic extravesical ureteral reimplantation (RALUR-EV) in infants. MATERIALS AND METHODS: Between April 2017 and July 2019, sixteen infants with primary obstructive megaureter (POM) (Age range: 4-12 months) underwent robot-assisted ureteral reimplantation were reviewed in this series. In addition to the conventional Lich-Gregoir technique, the detrusor tunnel has been extended to the mobilized anterior bladder wall to guarantee sufficient tunnel length/ureter diameter ratio and avoid ureteral angulation. All patients underwent repeated ultrasound, diuretic renal dynamic imaging and voiding cystourethrography (VCUG) perioperatively and the outcomes were documented. RESULTS: All operations were completed with robotic assisted approach without conversion. Bilateral and unilateral reimplantation were respectively performed in two and fourteen patients. The mean operative time was 115.0 ± 19.5 min and the mean blood loss was 10.0 ± 1.8 ml. There were no high-grade complications (III-IV on Clavien-Dindo classification) except for one patient. The distal ureteric diameter was reduced from pre operative 1.7 ± 0.5 to 0.6 ± 0.5 cm 6 months post operatively (p < 0.05). One child (6.3%) required the second reimplantation for stenosis. The overall operative success rate was 94.4% (17 of 18 ureters) with a mean follow-up of 15.9 ± 7.4 months with no flux detected. CONCLUSION: Our preliminary experience suggests that our modified robot-assisted laparoscopic extravesical ureteral reimplantation is feasible in infants with good results.