Research Scholarships 2019: Project 3

3D Bioprinting of Epithelial Tissue Models for Biomedicfal research (and Pre-clinical Trials)

PI: Dr Emmanuel Reynaud

As of today, "95% of drugs fail clinical trials because drug testing is performed on ineffective models"     – Forbes. There is a crucial need to improve the costly, inefficient and non-predictive nature of model systems. New technologies such as additive printing AKA 3D printing offers the possibility to create at will any shape and model you wish in a matter of hours and this has led to a disruptive manufacturing process for very complex parts in many fields including the aeronautic industry. Now, 3D bioprinting is a new player in biomedical research for organ transplant and tissue models. One of the essential tissues that account for a large amount of our body is the epithelium from your skin to your intestine, essential for our life as a protective barrier but also filtering food and nutrients but under attacks. This project aims at creating using a revolutionary 3D fluid bioprinter models for several type of epithelium to improve research and drug screening.

For the last century the majority of cell biology research was conducted using Two-Dimensional (2D) monolayers grown on hard and non-biologically functional surfaces. By growing cells in a Three-Dimensional (3D) configuration and providing additional biochemical cues and physical substrate factors it is possible to simulate the native cellular microenvironment (Pampaloni et al., 2007). This result in a behaviour which is more predictive of the in vivo state and produces more meaningful data. Unfortunately, there are many barriers in the way before the potential of 3D cell culture can be fully realised. 1) There are inconsistencies between the different 3D cell culture systems, and they lack adequate characterisation and references. 2) Few established protocols exist, and most are overly technical, labour intensive, expensive and require too many components. 3) All techniques need higher sample throughput, better scalability and improved adaptability. 4) Due to their large size and complexity imaging 3D cultures is problematic. By solving these problems, we can move towards addressing the most significant. I propose to use the newly developed Naiad, 3D bioprinter in liquid phase (Patent WO201_081040A1) to fabricate 3D replicas of epithelial tissue scaffolds which can be modified to further tailor the scaffold to investigate how epithelial structures are formed and the relationship between the biological element and the engineering constructs properties such as tensegrity. 3D printing was originally developed in 1984 by Chuck Hull and is an additive process of making a three-dimensional solid object from a digital model. This technique allows for the ability to create almost any shape or geometric feature. Among other uses, 3D printing has found promise in the biomedical field to generate tissue scaffolds out of biodegradable polymers as well as potentially tissues by printing cells and matrix into a defined area. The introduction of 3D bioprinting is expected to revolutionize the field of tissue engineering and regenerative medicine. The 3D bioprinter can dispense materials while moving in X, Y, and Z directions, which enables the engineering of complex scaffolds from the bottom up. A variety of polymers can be used for the printed scaffold, provided the polymer is bio-compatible, bio-degradable and non-toxic. Prior to printing as a bio-ink, the polymer can be modified to contain growth factors (Kuo and Wang, 2013) or to enhance cell attachment using peptide sequences (Lozano et al., 2015). Bio-printing scaffolds therefore provides a means by which cell survival and functionality can be enhanced prior to transplantation. This project aims to produce epithelial microtissues using different 3D bio-printed scaffolds. Further aims for use of such organoids would include cell colonization and tissue establishment as well as disruption; quantitative measurements of tissue and cell characteristics to create 3D reference cell map in volume using light sheet microscopy; time lapse of tissue dynamics using structural markers (GFP tagged actin, tubulin and intermediate filaments) as well as functional markers (e.g. secreted proteins). Finally, using mathematical modelling those organoids will be used to refine existing epithelial models.

This project is the follow up and collaboration with several 4th year projects and PhDs which have taken place in the Reynaud laboratory for the last three years.

Candidates should hold a BSc Hons degree in Biomedical Engineering, Cell Biology, Physiology., Pharmacology or related subject area.

 

Enquiries and applications (to include cover letter and CV) to Dr Emmanuel Reynaud.  Email: Emmanuel.reynaud@ucd.ie

Closing date:  Friday 31st May, 2019.