publication

Allevi Author - Valentine's Day Edition: GWU Bioprints Heart Tissue

cardiac muscle myocytes fibroblasts george washington university allevi 3d bioprinters and bionk

George Washington University joins the #AlleviAuthor club with their new paper titled, “Use of GelMA for 3D printing of cardiac myocytes and fibroblasts” and published in Journal of 3D Printing in Medicine.

First let’s review some basics about your heart! Heart tissue is composed of two main cell types; cardiac fibroblasts (CFB) & cardiomyocytes (CMC).

 
cardiac+myocytes+and+fibroblasts+allevi+GWU.jpg
 

Cardiomyocytes are the contracting cells which allow the heart to pump. Each cardiomyocyte needs to contract in coordination with its neighboring cells to efficiently pump blood from the heart, and if this coordination breaks down then the heart may not pump at all.

Fibroblast cells give support to the muscle tissue. They are unable to provide forceful contractions like cardiomyocytes, but instead are largely responsible for creating and maintaining the extracellular matrix which forms the mortar in which cardiomyocyte bricks are embedded. Fibroblasts also play a crucial role in responding to injury by creating collagen while gently contracting to pull the edges of the injured area together.

In previous academic studies, tests of pure populations of cardiomyoctes have failed to stay viable making it difficult to study the heart in a lab setting. In their recent paper, the team at George Washington University set out to determine how 3D bioprinting affects these two types of cells and if there is a way to create viable 3D tissue in the lab by bioprinting both CMCs and CFBs in tandem.

The team studied the effects of temperature, pressure, bioink composition, and UV exposure to determine the best conditions for 3D bioprinting heart muscle.

Through LIVE/DEAD assays, bioluminescence imaging and morphological assessment, they determined that cell survival within a 3D bioprinted CMC-laden GelMA construct was MORE sensitive to extruder pressure and bioink composition than the fibroblast-laden constructs. Also they determined that BOTH cell types were adversely impacted by the UV curing step. And finally they determined that using a mixture of cardiomyocytess and cardiac fibroblasts increased viability of the tissue- showing that CMCs <3 CFBs.

Cheers to the team at GWU! Their research creates an important foundation for future studies of 3D bioprinted heart tissue.

Read their paper here.

Allevi Author: Tohoku University Images Cell Activity in Hyrdrogels

tohoku university allevi bioprinter bioprinted hydrogel imaging

One of the most rewarding “AHA” moments of bioprinting is seeing your cells proliferate within a 3D tissue. As 3D bioprinting becomes more widely adopted within the fields of tissue engineering and personalized medicine, it is important that researchers have the ability to monitor cell activity within in a 3D structure AFTER the print is finished.

Our most recent Allevi Authors have tackled the method of electrochemically monitoring a tissue in their new paper out in the Analytical Sciences Journal titled, “Electrochemical Imaging of Cell Activity in Hydrogels Embedded in Grid-Shaped Polycaprolactone Scaffolds Using a Large-scale Integration (LSI)-based Amperometric Device”.

In their paper, researchers from Tohoku University in Japan use their Allevi 2 bioprinter to print PCL scaffolds as a support material for photocured hydrogels. They then used an amperometric device to electrochemically monitor the living cells. Through their study, they were able to determine that electrochemical imaging is a great way to monitor cell differentiation and will be useful for evaluating the viability of thicker bioprinted tissues.

Congratulations to the Tohoku University researchers on their findings!

Allevi Author: UPenn bioprints custom nasal defects

Allevi 2 bioprinter bioprints nasal bone nose cartilage

We're proud to bring you yet another #AlleviAuthor - this one from down the street at University of Pennsylvania.  Dr. Chamith Rajapakse's Lab at UPenn focuses on the development and application of image guided 3D bioprinting for personalized clinical applications.

In his most recent publication, Dr. Rajapakse bioprinted a scaffold that precisely matched a patient’s nasal septal defect, in both size and shape using the Allevi 2 bioprinter. This serves as the first step in a major goal to create patient-specific tissue engineered grafts for NSP repair and beyond.

Here at Allevi, we envision a future of truly personalized medicine. The research by Dr. Rajapakse and his lab brings this future that much closer within the bone, cartilage and muscle tissue types.  One can being to imagine the future of being able to reconstruct cleft palates, nasal septal perforations, broken bones, torn ligaments, vertebrae and so much more.

Read on for the abstract and check out the full publication here.

Abstract: Nasal septal perforations (NSPs) are relatively common. They can be problematic for both patients and head and neck reconstructive surgeons who attempt to repair them. Often, this repair is made using an interpositional graft sandwiched between bilateral mucoperichondrial advancement flaps. The ideal graft is nasal septal cartilage. However, many patients with NSP lack sufficient septal cartilage to harvest. Harvesting other sources of autologous cartilage grafts, such as auricular cartilage, adds morbidity to the surgical case and results in a graft that lacks the ideal qualities required to repair the nasal septum. Tissue engineering has allowed for new reconstructive protocols to be developed. Currently, the authors are unaware of any new literature that looks to improve repair of NSP using custom tissue-engineered cartilage grafts. The first step of this process involves developing a protocol to print the graft from a patient's pre-operative CT.

In this study, CT scans were converted into STereoLithography (STL) file format. The subsequent STL files were transformed into 3D printable G-Code using the Slic3r software. This allowed us to customize the parameters of our print and we were able to choose a layer thickness of 0.1mm.  A desktop 3D bioprinter (Allevi 2) was then used to construct the scaffold.

This method resulted in the production of a PCL scaffold that precisely matched the patient’s nasal septal defect, in both size and shape. This serves as the first step in our goal to create patient-specific tissue engineered nasal septal cartilage grafts for NSP repair.

Allevi Author: Allevi and Dr. Anthony Atala

Allevi Author publication

With a 12% success rate for drugs entering clinical trials, there is no doubt that drug companies need more accurate prediction platforms to help them save billions in bringing a drug to market. 3D cellular models, such as spheroids, organoids and organ-on-chips, offer a promising solution to this issue. But how can these models be built at the complexity and scale needed for pharma? Bioprinting’s ability for increased complexity and automation is the clear answer.

Read our co-authored paper with Dr. Anthony Atala, Director of the Wake Forest Institute for Regenerative Medicine (WFIRM) and featured on TED, describing the potential of bioprinting to improve drug testing. 

“Bioprinted organoids can potentially provide significant benefits to drug companies and patients alike,” said Atala. “More accurate and faster testing brings new drugs to market sooner, and the possibility of engineering tumors in the lab from a patient’s own cells mean patients can get the best therapy right away – without time spent taking therapies that won’t work for them.” 

Allevi Author: Nathan from Drexel Univ First-authors this study of hydrogels

nathan tessema ersumo drexel University spiller lab allevi

Onto a very special #AlleviAuthor - our user Nathan Tessema Ersumo was an undergrad from Dr. Kara Spiller's Lab at Drexel University when he FIRST authored this beauty.

Nathan used the Allevi BetaBot to study the mechanical properties of different hydrogels for applications within tissue engineering.  There are still many unknowns about the mechanical properties of biomaterials before and after printing. Nathan's paper studies the the differences in the Young's moduli between bioprinted and molded constructs. 

We're especially proud of this work because it highlights a core aspect of our mission here at Allevi; accessibility. We design our platforms to be accessible and affordable to everyone in the lab. That versatility and ease of use makes it possible to make novel discoveries like this one and to #buildwithlife (even during the undergrad years). 

You can download and read the publication here.