Biology subjects

Kado Abdalkader, R.

Publications and source records attributed to Kado Abdalkader, R..

3 recordsLinked to original sources

bioRxiv2025

3D-printed microfluidic chip for modeling retinal organoid-endothelial co-culture

Pathological angiogenesis, such as that observed in wet age-related macular degeneration (AMD), is challenging to reproduce in vitro. While previous organ-on-chip approaches have incorporated retinal pigment epithelium (RPE) and endothelial barriers, models integrating human retinal organoids with vascular networks remain limited. Here, we report the development of a fully 3D-printed microfluidic device for co-culture of human induced pluripotent stem cell (hiPSC)-derived retinal organoids containing RPE regions with endothelial cells. The device, fabricated from flexible thermoplastic polyurethane (TPU) on a transparent polyvinyl chloride (PVC) substrate, enables direct organoid-endothelial interaction within a fibrin-Matrigel matrix without physical barriers. In this system, endothelial cells formed choroid-like networks that integrated with retinal organoids. Vascular network density and invasion into RPE regions were enhanced by VEGF stimulation, recapitulating features of wet AMD. Furthermore, fluorescent liposomes distributed along endothelial structures and accumulated at the organoid interface, supporting the application of this model for nanoparticle delivery studies. This 3D-printed retinal organoid-on-chip provides a simple, reproducible, and physiologically relevant platform that complements existing retinal models for investigating angiogenesis and evaluating therapeutic strategies.

bioengineering↗

bioRxiv2025

A 3D-printed pump-free multi-organ-on-a-chip platform for modeling the intestine-liver-muscle axis

The intestine-liver-muscle axis plays an essential role in drugs and nutrients absorption, metabolism, and energy balance. Yet in vitro models capable of recapitulating this inter-organ communication remain limited. Here, we present a pump-free, 3D-printed multi-organ-on-a-chip device that enables dynamic co-culture of Caco-2 intestinal epithelial cells, HepG2 hepatocytes, and primary human skeletal myoblasts (HSkM) under gravity-driven oscillatory flow. The device consists of five interconnected chambers designed to accommodate Transwell cell culture inserts for intestine and muscle compartments and hydrogel-embedded hepatocyte spheroids in the central hepatic compartment. The device was fabricated by low-cost fused deposition modeling (FDM) using acrylonitrile butadiene styrene (ABS) polymers. Under dynamic rocking, oscillatory perfusion promoted inter-organ communication without the need for external pumps or complex tubing. Functional assessments revealed that dynamic co-culture significantly enhanced the functions of skeletal muscle, as indicated by increased myosin heavy chain expression and elevated lactate production, while HepG2 spheroids exhibited improved hepatic function with higher albumin expression compared with monoculture. Additionally, Caco-2 cells maintained stable tight junctions and transepithelial electrical resistance, demonstrating preserved intestinal barrier integrity under dynamic flow. These results establish the device as a versatile, accessible 3D-printed platform for modeling the intestine-liver-muscle axis and investigating metabolic cross-talk in drug discovery and disease modeling.

bioengineering↗

bioRxiv2024

Development and characterization of bioinks for 3D bioprinting of in vitro skeletal muscle constructs

The use of 3D bioprinting to construct in vitro skeletal muscle models presents a promising approach; however, selecting an optimal bioink remains a common challenge. This study focuses on the development and characterization of bioinks for extrusion-based 3D bioprinting, specifically targeting the creation of accurate skeletal muscle models. By exploring various compositions of alginate, gelatin, fibrinogen, and nanofiber cellulose, we evaluate these formulations based on printability and their support for the growth and differentiation of C2C12 myoblast cells. While alginate provided a strong, stable matrix for printing scaffolds embedded with C2C12 cells, it did not effectively promote cell growth and differentiation. The addition of fibrinogen to alginate enhanced cell growth and differentiation but was limited mainly to the scaffold surfaces, even with the inclusion of gelatin as a sacrificial ink. Notably, replacing alginate with nanofiber cellulose (NFC) alongside fibrinogen significantly improved cell growth and differentiation, leading to the formation of mature myotubes. Cell distribution was observed both inside and on the surfaces of the scaffolds, indicating effective spatial cell distribution. Furthermore, the scaffolds were tailored to form skeletal muscle bundles anchored between PDMS pillars for contractility testing. Upon exposure to electrical stimulation, the cells displayed measurable displacement, demonstrating contractile function. These findings offer valuable insights into optimizing bioink formulations that promote myoblast growth and differentiation into skeletal muscle in vitro, with potential applications in future neuromuscular disease modeling.

bioengineering↗