PubMed Health⌕ Search

Biomedical subjects

Roger E De Filippo

Publications and source records attributed to Roger E De Filippo.

4 recordsLinked to original sources

Extracellular vesicle miR-93-5p cargo regulates glomerular endothelial cell damage in Alport syndrome.

Modulation of miRNA expression in glomerular cells is associated with renal disease. Here, we investigated the role of miR-93-5p in mitigating glomerular damage in Alport syndrome and whether the disease-modifying activity of extracellular vesicles from human amniotic fluid stem cells (hAFSC-EVs) is mediated by their miR-93-5p cargo. We identified downregulation of miR-93-5p specifically in glomerular endothelial cells in Alport syndrome along disease progression. Silencing of miR-93-5p in hAFSC-EVs changed the transcriptomic and proteomic profile, regulating EV disease-modifying activity. Compared with naive hAFSC-EVs, silenced hAFSC-EVs did not rescue glomerular endothelial function in vitro and did not restore kidney function in vivo. We established that hAFSC-EVs regulate VEGFR1 and VEGFR2 signaling by miR-93-5p cargo transfer, highlighting that miR-93-5p can restore glomerular endothelial cell biology. Spatial transcriptomics analysis of hAFSC-EV-injected kidneys showed that these EVs can reverse pathways altered during disease progression by stimulating proregenerative processes, specifically in the glomerulus, by regulating miR-93-5p targets. Alteration of glomerular endothelial cell transcriptomics and miR-93-5p targets was also confirmed in biopsies of patients with Alport syndrome using spatial molecular imaging. We demonstrated the critical role of miR-93-5p in glomerular endothelial cells and the capability of hAFSC-EVs to regulate miR-93-5p and its targets in Alport syndrome.

Humans↗

Engineering of vaginal tissue in vivo.

Congenital vaginal anomalies and cloacal malformations may require extensive surgical reconstruction. Surgical challenges are often encountered because of the limited amounts of native tissue available. We investigated the feasibility of using vaginal epithelial and smooth muscle cells for the engineering of vaginal tissues in vivo. Vaginal epithelial and smooth muscle cells of female rabbits were grown, expanded in culture, and characterized immunocytochemically. Vaginal epithelial and smooth muscle cells were seeded on polyglycolic acid (PGA) scaffolds at 10 x 10(6) and 20 x 10(6) cells/cm(3), respectively. The cell-seeded scaffolds were subcutaneously implanted into nude mice. The animals were killed 1, 4, and 6 weeks after implantation. Immunocytochemical and histochemical analyses were performed with pancytokeratins AE1/AE3 and with smooth muscle-specific alpha-actin antibodies to confirm the reconstituted tissue phenotype. Western blot analyses and electrical field stimulation studies were also performed to further characterize the tissue-engineered constructs. Vaginal epithelial cells were serially identified with anti-pancytokeratins AE1/AE3 at all culture stages. Smooth muscle cells in culture stained positively with alpha-smooth muscle actin antibodies. One week after implantation in vivo, the retrieved polymer scaffolds demonstrated multilayered tissue strips of both cell types, and penetrating native vasculature was also noted. Increased organization of the smooth muscle and epithelial tissue was evident by 4 weeks. There was no evidence of tissue formation in the controls. Immunocytochemical analyses using anti-pancytokeratins confirmed the presence of vaginal epithelial cells in each of the constructs. Anti-alpha-actin smooth muscle antibodies also confirmed the presence of multilayered smooth muscle fibers and tissue at each time point. Western blot analyses of the scaffolds confirmed the expression of cytokeratin and smooth muscle actin proteins when compared with controls. The contractile properties of the tissue-engineered vaginal constructs in response to electrical field stimulation were similar to those of normal vaginal tissue. Vaginal epithelial and smooth muscle cells can be easily cultured and expanded in vitro. Cell-seeded polymer scaffolds are able to form vascularized vaginal tissue in vivo that have phenotypic and functional properties similar to those of normal vaginal tissues. This is the first demonstration in tissue engineering wherein vaginal epithelial and smooth muscle cells are reconstituted in vivo into vaginal tissue. This technology may be pursued further experimentally in order to achieve the engineering of vaginal tissues for clinical applications.

Actins↗

Urethral replacement using cell seeded tubularized collagen matrices.

PURPOSE: Acellular collagen matrices derived from bladder submucosa have been used successfully as an off-the-shelf biomaterial for urethral replacement, experimentally and clinically in an onlay fashion. We investigated whether collagen matrices, either alone or with autologous cells, could be used for tubularized urethral replacement. MATERIALS AND METHODS: Acellular collagen matrices were processed and tubularized. Ten rabbits underwent an open bladder biopsy with subsequent cell expansion. Autologous bladder cells were grown and seeded onto the pre-configured tubular matrices. A 1 cm. long urethral segment was excised in 24 male rabbits. Urethroplasty was performed with the tubularized collagen matrices seeded with cells in 12 animals and without cells in 12. Serial urethrography was performed preoperatively and at 1, 2, 3 and 6 months postoperatively. Retrieved urethras were analyzed grossly, histologically, immunocytochemically and with Western blots. Contractility and the presence of neurotransmitter receptors were confirmed with organ bath studies. RESULTS: Serial urethrography confirmed the maintenance of a wide urethral caliber without any signs of strictures in animals implanted with the cell seeded matrices. The urethral segments replaced with the collagen scaffolds without cells demonstrated strictures and graft collapse at all time points. The implanted cell seeded matrices had a normal urethral architecture by 1 month, consisting of a transitional cell layer surrounded by muscle cell fiber bundles with increasing cellular organization with time. Epithelial and smooth muscle phenotypes were confirmed immunocytochemically and with Western blot analyses using pancytokeratins AE1/AE3 and smooth muscle specific alpha-actin antibodies. Formation of a transitional cell layer was confirmed in the matrices implanted without cells but only scant unorganized muscle fiber bundles were present, mostly at the anastomotic sites. Organ bath studies demonstrated the capacity for contractility along with cholinergic and adrenergic specific receptors in the tissue engineered scaffolds compared to controls. CONCLUSIONS: These results show that collagen matrices seeded with cells form normal urethral tissue can be used for tubularized replacement, whereas tubularized collagen matrices alone without cells lead to poor tissue formation and strictures. The collagen matrices seeded with cells may offer a useful alternative in the future for patients requiring a tubularized urethral segment replacement.

Animals↗