The concept behind organ-on-a-chip (OoC) technology is to replicate human organs’ physiological and functional properties by combining advancements in tissue engineering and microfabrication. Traditional in vitro cell culture models lack physiological complexity, while in vivo animal models raise ethical concerns, exhibit interspecies differences, and have limited translatability. OoCs are designed to mimic tissue-specific functions by regulating cell microenvironments, providing a platform to study organ-level physiology.
A crucial component in maintaining organ and tissue function is the blood vasculature, which consists of an intricate network of blood vessels throughout the body, essential for maintaining homeostasis by removing metabolic waste products and transporting oxygen and nutrients. Tissue-engineered grafts with wall thickness greater than the diffusion limit of gases and nutrients (150–200 μm) require a pre-formed vascular network. What is currently available on the market serves as a natural reservoir of growth factors, cytokines, and extracellular matrix (ECM) proteins but lacks essential pre-formed vasculature. Consequently, tissue-engineered grafts fail to integrate with the host and eventually undergo necrosis.
Achieving a matured structural organisation within tissue and modelling perfusable vessels is a challenging task. Researchers encounter difficulties in maintaining the viability of cells within the microfluidic vascular networks and achieving optimal fluid flow and perfusion rates. A common solution to mimic the microenvironment of the blood vessel network is to apply mechanical stimulation, which significantly influences neovascularisation and angiogenesis, or to release vascular endothelial growth factors (VEGFs) to trigger therapeutic angiogenesis processes.
She aims to combine both methods on a microfluidic chip to find a balance of biomechanical and biochemical cues to recreate the physiological microenvironment of neovascularisation in vitro. By applying flow control, she hopes to establish complex microenvironment concentrations at physiological levels by regulating chemical factors (e.g., molecular gradients of growth factors from platelet lysate) or mechanical factors (shear force from interstitial flow).