A team of bioengineers and biomedical scientists from the University of Sydney and the Children's Medical Research Institute (CMRI) at Westmead have used 3D photolithographic printing to create a complex environment for assembling tissue that mimics the architecture of an organ.
The teams were led by Professor Hala Zreiqat and Dr. Peter Newman at the University of Sydney's School of Biomedical Engineering and developmental biologist Professor Patrick Tam who leads the CMRI's Embryology Research Unit. Their paper was published in Advanced Science.
Using bioengineering and cell culture methods, the technique was used to instruct stem cells derived from blood cells or skin cells to become specialized cells that can assemble into an organ-like structure.
Similar to how the needle of a record player navigates the vinyl grooves to create music, cells use strategically positioned proteins and mechanical triggers to navigate through their intricate environment, replicating developmental processes. The team's latest research employed microscopic mechanical and chemical signals to recreate the cellular activities during development.
Professor Hala Zreiqat said, "Our new method serves as an instruction manual for cells, allowing them to create tissues that are better organized and more closely resemble their natural counterparts. This is an important step towards being able to 3D print working tissue and organs."
Cell-friendly Bioprinting at High Fidelity Enhances Its Medical Applicability October 16, 2023
Introduction:
(Eurekalert) Osaka, Japan – What if organ damage could be repaired by simply growing a new organ in the lab? Improving researchers’ ability to print live cells on demand into geometrically well-defined, soft complex 3D architectures is essential to such work, as well as for animal-free toxicological testing.
In a study recently published in ACS Biomaterials Science and Engineering, researchers from Osaka University have overcome prior limitations that have hindered cell growth and the geometrical fidelity of bioprinted architectures. This work might help bring 3D-printed cell constructs closer to mimicking biological tissue and organs.
Further extracts:
“In our approach, a 3D printer alternately dispenses the cell-containing ink and a printing support," explains Takashi Kotani, lead author of the study. “The interesting point is that the support also plays a role in facilitating the solidification of the ink. All that’s necessary for ink solidification is in the support, and after removing the support, the geometry of the soft printed cell structures remains intact.”
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“We largely retain mouse fibroblast cell geometry and growth, and the cells remain viable for at least two weeks,” says Shinji Sakai, senior author. “These cells also adhere to and proliferate on our constructs, which highlights our work’s potential in tissue engineering.”
This new technique is an important step forward to engineering human cell assemblies and tissues. Further work might involve further optimizing the ink and support, as well as incorporating blood vessels into the artificial tissue to improve its resemblance to physiological architectures. Regenerative medicine, pharmaceutical toxicology, and other fields will all benefit from this work and further improvements in the precise fidelity of bioprinting.
Application of artificial intelligence in 3D printing physical organ models Liang Ma, Shijie Yu, Xiaodong Xu, Sidney Moses Amadi, Jing Zhang and Zhifei Wang
Highlights
• Physical organ models are highly simulated and provide accurate simulation of human organs for medical training and surgical planning.
• 3D printing can create complex physical organ models and reduce production time.
• The use of artificial intelligence in 3D printing offers the potential to efficiently print high-quality physical organ models.
Abstract
Artificial intelligence (AI) and 3D printing will become technologies that profoundly impact humanity. 3D printing of patient-specific organ models is expected to replace animal carcasses, providing scenarios that simulate the surgical environment for preoperative training and educating patients to propose effective solutions. Due to the complexity of 3D printing manufacturing, it is still used on a small scale in clinical practice, and there are problems such as the low resolution of obtaining MRI/CT images, long consumption time, and insufficient realism. AI has been effectively used in 3D printing as a powerful problem-solving tool. This paper introduces 3D printed organ models, focusing on the idea of AI application in 3D printed manufacturing of organ models. Finally, the potential application of AI to 3D-printed organ models is discussed. Based on the synergy between AI and 3D printing that will benefit organ model manufacturing and facilitate clinical preoperative training in the medical field, the use of AI in 3D-printed organ model making is expected to become a reality.
Scientists 3D-print hair follicles in lab-grown skin
The technique represents an important step in engineering skin grafts, drug testing
By Samantha Murray
https://news.rpi.edu/content/2023/11/15 ... grown-skin
A team led by scientists at Rensselaer Polytechnic Institute has 3D-printed hair follicles in human skin tissue cultured in the lab. This marks the first time researchers have used the technology to generate hair follicles, which play an important role in skin healing and function.
The finding, published in the journal “Science Advances,” has potential applications in regenerative medicine and drug testing, though engineering skin grafts that grow hair are still several years away.
Engineers at Duke University and Harvard Medical School have developed a bio-compatible ink that solidifies into different 3D shapes and structures by absorbing ultrasound waves. Because it responds to sound waves rather than light, the ink can be used in deep tissues for biomedical purposes ranging from bone healing to heart valve repair.
This work appears on in the journal Science.
The uses of 3D-printing tools are ever increasing. Printers create prototypes of medical devices, design flexible, lightweight electronics, and even engineer tissues used in wound healing. However, many of these printing techniques involve building the object point-by-point in a slow and arduous process that often requires a robust printing platform.
To circumvent these issues over the past several years, researchers developed a photo-sensitive ink that responds directly to targeted beams of light and quickly hardens into a desired structure. While this printing technique can substantially improve the speed and quality of a print, researchers can only use transparent inks for the prints, and biomedical purposes are limited, as light can't reach beyond a few millimeters deep into the tissue.
New ultrasound tech could be used to 3D-print implants inside the body
By Ben Coxworth
December 08, 2023
In order to keep surgeries minimally invasive, it would be great if implants could be injected into the body in liquid form, then solidified once in place. Well, a new ultrasound-based 3D printing process may one day make that very thing possible.
The most common type of 3D printing involves building three-dimensional objects by depositing successive layers of viscous material that subsequently hardens. Another established method of 3D printing, known as volumetric printing, involves shining beams or patterns of light through the transparent top and sides of a container, inside of which is a photosensitive gelatinous resin.
Wherever that resin is exposed to the light, it polymerizes (solidifies) – the rest of the resin in the container remains a gel. By moving the light source around, so it reaches different parts of the resin, it's possible to gradually build up a very detailed three-dimensional object.
One of the limiting factors of volumetric printing is the fact that for the light to reach its target, the container and the resin have to be transparent. Because human skin and biological tissue are nearly opaque, light can only reach a few millimeters through them. This means that in its current form, the technique can't be used to build implants within the body.
Rochester undergraduates have developed a 3D-bioprinting system to replicate chemicals found in plants, including those endangered by climate change.
Imagine a world without plants. Although this extreme scenario has not become a reality, Earth is facing a concerning trend—the rapid depletion of potential plant-derived drugs. Globally, tens of thousands of flowering plant species play vital roles in medicinal applications, but many of the pharmaceuticals dominating the United States market heavily rely on imported raw plant materials that require very particular climate conditions for optimal growth.
Is it possible to grow tissue in the laboratory, for example to replace injured cartilage? At TU Wien (Vienna), an important step has now been taken toward creating replacement tissue in the lab—using a technique that differs significantly from other methods used around the world. The study is published in Acta Biomaterialia.
A special high-resolution 3D printing process is used to create tiny, porous spheres made of biocompatible and degradable plastic, which are then colonized with cells. These spheroids can then be arranged in any geometry, and the cells of the different units combine seamlessly to form a uniform, living tissue. Cartilage tissue, with which the concept has now been demonstrated at TU Wien, was previously considered particularly challenging in this respect.
You can mend a broken heart this Valentine's Day now that researchers have invented a new hydrogel that can be used to heal damaged heart tissue and improve cancer treatments.
University of Waterloo chemical engineering researcher Dr. Elisabeth Prince teamed up with researchers from the University of Toronto and Duke University to design the synthetic material made using cellulose nanocrystals, which are derived from wood pulp. The material is engineered to replicate the fibrous nanostructures and properties of human tissues, thereby recreating its unique biomechanical properties.
The research was recently published in the Proceedings of the National Academy of Sciences.
