3D bioprinting technique controls cell orientation

3D bioprinting technique controls cell orientation
Biofabrication of multicompartmental hydrogel fibers for formation of multiscale biomimetic constructs. Credit: Mohamadmahdi Samandari, Fatemeh Alipanah, Keivan Majidzadeh-A, Mario M. Alvarez, Grissel Trujillo-de Santiago, and Ali Tamayol

3D bioprinting can create engineered scaffolds that mimic natural tissue. Controlling the cellular organization within those engineered scaffolds for regenerative applications is a complex and challenging process.

Cell tissues tend to be highly ordered in terms of spatial distribution and alignment, so bioengineered cellular scaffolds for engineering applications must closely resemble this orientation to be able to perform like natural tissue.

In Applied Physics Reviews, from AIP Publishing, an international research team describes its approach for directing cell orientation within deposited hydrogel fibers via a method called multicompartmental .

The team uses static mixing to fabricate striated hydrogel fibers formed from packed microfilaments of different hydrogels. In this structure, some compartments provide a favorable environment for , while others act as morphological cues directing cell alignment. The millimeter-scale printed fiber with the microscale topology can rapidly organize the toward faster maturation of the engineered tissue.

"This strategy works on two principles," said Ali Tamayol, coauthor and an associate professor in biological engineering at UConn Health. "The formation of topographies is based on the design of fluid within nozzles and controlled mixing of two separate precursors. After crosslinking, the interfaces of the two materials serve as 3D surfaces to provide topographical cues to cells encapsulated within the cell permissive compartment."

Extrusion-based bioprinting is the most widely used bioprinting method. In extrusion-based bioprinting, the printed fibers are typically several hundreds of micrometers in size with randomly oriented cells, so a technique providing topographical cues to the cells within these fibers to direct their organization is highly desirable.

Conventional extrusion bioprinting also suffers from high shear stress applied to the cells during the extrusion of fine filaments. But the fine scale features of the proposed technique are passive and do not compromise other parameters of the printing process.

To direct cellular organization, according to the team, extrusion-based 3D-bioprinted scaffolds should be made from very fine filaments.

"It makes the process challenging and limits its biocompatibility and the number of materials that can be used, but with this strategy larger filaments can still direct cellular organization," said Tamayol.

This bioprinting technique "enables production of tissue structures' morphological features—with a resolution up to sizes comparable to the cells' dimension—to control cellular behavior and form biomimetic structures," Tamayol said. "And it shows great potential for engineering fibrillar tissues such as skeletal muscles, tendons, and ligaments."

Explore further

New bioprinting technique allows for complex microtissues

More information: Mohamadmahdi Samandari et al, Controlling cellular organization in bioprinting through designed 3D microcompartmentalization, Applied Physics Reviews (2021). DOI: 10.1063/5.0040732
Journal information: Applied Physics Reviews

Citation: 3D bioprinting technique controls cell orientation (2021, May 5) retrieved 14 June 2021 from https://phys.org/news/2021-05-3d-bioprinting-technique-cell.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments