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Biology subjects

Ayollo, D.

Publications and source records attributed to Ayollo, D..

3 recordsLinked to original sources

Therapeutic potential of human mesenchymal stromal cell-derived mitochondria in a rat model of post-surgical digestive fistula: towards an energetic nano-biotherapy

BackgroundTissue regeneration heavily relies on cellular energy production, with mitochondria playing a crucial role. Dysfunctional mitochondria are implicated in various degenerative diseases, driving interest in targeting mitochondrial transplantation for tissue repair. Wound healing is highly compromised in gastrointestinal conditions resulting in fistula development, particularly after sleeve gastrectomy. Human mesenchymal stem/stromal cells (hMSCs) and their cell-free products such as mitochondria offer potential benefits due to their therapeutic properties on cellular energy production. Here we investigated the therapeutic advantage of hMSCs-derived mitochondria nano-biotherapy in a rat model of post-surgical fistula healing. MethodsViable and structurally intact mitochondria were isolated from hMSCs before exposure to human colonic epithelial cells (HCEC-1CT) culture or transplantation into a rat model of post-operative fistula. ResultsOur findings reveal significant dose-dependent improvement on cellular metabolic activity and ATP content of the recipient cells. Assessment of the external fistula orifice developed following post sleeve gastrectomy fistula, revealed a substantial healing in all transplanted rats compared to control group. ConclusionOur findings highlight the therapeutic potential of hMSCs-derived mitochondria in post-surgical fistula healing. This research contributes to advancing cell-free regenerative strategies for gastrointestinal conditions, offering new insights into mitochondrial-based therapies for enhancing wound healing and tissue repair.

systems biology↗

Self-organization of Long-lasting Human Endothelial Capillary Networks guided by DLP Bioprinting

Tissue engineering holds great promise for regenerative medicine, drug discovery and as an alternative to animal models. However, as soon as the dimensions of engineered tissue exceed the diffusion limit of oxygen and nutriments, a necrotic core forms leading to irreversible damage. To overcome this constraint, the establishment of a functional perfusion network is essential and is a major challenge to be met. In this work, we explore a promising Digital Light Processing (DLP) bioprinting approach to encapsulate endothelial progenitor cells (EPCs) in 3D photopolymerized hydrogel scaffolds to guide them towards vascular network formation. We observed that EPCs encapsulated in the appropriate photopolymerized hydrogel can proliferate and self-organize within a few days into branched tubular structures with predefined geometry, forming capillary-like vascular tubes or trees of various diameters (in the range of 10 to 100 m). Presenting a monolayer wall of endothelial cells strongly connected by tight junctions around a central lumen, these structures can be microinjected with fluorescent dye and are stable for several weeks in vitro. Interestingly, our technology has proven to be versatile in promoting the formation of vascular structures using a variety of vascular cell lines, including EPCs, human vascular endothelial cells (HUVECs) and human dermal lymphatic endothelial cells (HDLECs). We have also demonstrated that these vascular structures can be recovered and manipulated in an alginate patch without altering their shape or viability. This opens new opportunities for future applications, such as stacking these endothelial vascular structures with other cell sheets or multicellular constructs to yield bioengineered tissue with higher complexity and functionality.

bioengineering↗

Construction of functional biliary epithelial branched networks with predefined geometry using digital light stereolithography

Cholangiocytes, biliary epithelial cells, are known to spontaneously self-organize into spherical cysts with a central lumen. In this work, we explore a promising biocompatible stereolithographic approach to encapsulate cholangiocytes into geometrically-controlled 3D hydrogel structures to guide them towards the formation of branched tubular networks. We demonstrate that within the appropriate mix of hydrogels, normal rat cholangiocytes can proliferate, migrate and organize into branched tubular structures, form walls consisting of a cell monolayer, transport fluorescent dyes into the luminal space and show markers of epithelial maturation such as primary cilia. The resulting structures have dimensions typically found in the intralobular and intrahepatic bile ducts and are stable for weeks, without any requirement of bulk supporting material, thereby offering total access to the basal side of these biliary epithelial constructs.

bioengineering↗