Controlled microvasculature for organ-on-a-chip applications produced by high-definition laser patterning

Area of Science:

• Biotechnology and Biomedical Engineering
• Tissue Engineering
• Microfluidics

Background:

• Organs-on-Chips (OoCs) are advanced 3D models for replicating human organ functions *in vitro*.
• Developing complex microvasculature within OoCs is crucial for accurate drug development but remains a challenge.
• Traditional 2D cultures and animal models have limitations in predicting human responses.

Purpose of the Study:

• To demonstrate femtosecond laser patterning for creating microvascular channels in a collagen matrix within microfluidic chips.
• To assess the physiological relevance and barrier function of the engineered microvasculature.
• To investigate the response of the microvascular system to inflammatory stimuli.

Main Methods:

• Utilized femtosecond laser patterning to fabricate hollow microvascular-like channels within a collagen-based hydrogel matrix.
• Optimized hydrogel preparation for structural stability and successful endothelialization.
• Assessed endothelial marker expression (ZO-1, VE-cadherin) and barrier function, and evaluated responses to TNF-α.

Main Results:

• Successfully created stable, endothelialized microvascular channels using femtosecond laser patterning.
• Demonstrated physiological relevance through expression of key endothelial markers and successful barrier function.
• Observed concentration-dependent increases in vascular permeability and ICAM-1 expression upon TNF-α exposure.

Conclusions:

• Femtosecond laser patterning offers a controllable method for vascularizing OoC platforms.
• The engineered microvasculature accurately mimics physiological and inflammatory vascular responses.
• This technique enhances the potential of OoCs for drug development and disease modeling.