Bioinks development in order to explore different biomimetic strategies for cartilage regenerative medicine
Lead Research Organisation:
Newcastle University
Department Name: Sch of Engineering
Abstract
Aim and objectives
The main aim of my PhD work is to develop and evaluate scalable process for the production of in vitro healthy and pathological models representative of cartilage tissue as platforms for testing novel pharmaceutical treatments. The relative objectives (OBJ) are:
OBJ1: To review the literature on current methods for the production and maintenance of in vitro healthy and pathological cartilage models and their lack to be filled;
OBJ2: To establish protocols for manufacturing in vitro cartilage tissue;
OBJ3: To develop scalable bioprinted processes for the generation of cartilage models in vitro and to assess the quality of the tissues and use them for further drug screening.
Background
The use of in vitro models is promising in increasing our understanding mainly on physiology, biology, and progression of diseases in order to be used as drug screening systems.In the last decade creating in vitro 3D tissue models, developed to a level in which living constructs, can closely mimic the native tissue environment in a high-throughput platform. Drug discovery is an inefficient procedure with a high failure rate and an extreme financial expense. From the compatibility point of view, studies on animals do not always are trustable in terms of results in human trials, and the regulatory environment is becoming stricter as time progresses. From the moral perspective, attempts should be made to reduce the number of animal studies conducted according to the 3R's principles (Replacement, Reduction and Refinement) based on a more ethical use of animals in testing. Although several fabrication techniques have been used to develop these models, 3D bioprinting technologies are advantageous owing to their low cost and efficiency, high throughput, excellent reproducibility, and ability to create complex geometries as the cartilage tissue. Currently cartilage tissue engineering strategies are insufficient for reproducing tissue that is equivalent to healthy and pathological cartilage. At the moment there has been greater interest in studying the zonal differences found in cartilage matrix and cellular composition and bioprinting presents an appealing tool for constructing stratified scaffolds, especially in patient-specific size and shape of individual lesions with control over spatial resolution, shape, and mechanical properties. Thus, it could be interesting to reproduce and compare 3D models of osteoarthritic and healthy cartilage tissue in order to validate in vitro new alternative treatments (i.e. drug screening).
Methods
I am going to use natural-based polymers, such as chondroitin sulphate or chitosan blended with gellan gum or alginate for comparing different bioinks properties with the aim of finding the best solution in terms of printability, cells viability and tissue formation. The selected biofabrication technique is an extrusion-based 3D Bioprinter, ROKIT Invivo which allows users to create versatile 3D cell-laden structures, multi-layered with different materials and extensive designs. The printing system is made of a polymer extruder, a biodispenser with controlled temperature in the range of -4-80 C and an hot pneumatic dispenser (up to 350 C). Synthetic biopolymer as well as various hydrogel for scaffold generation can be used and for this reason Rokit is an optimized tool for many biomedical research with its modular system and sterile environmental, because provided with a H14 grade Hepa filter for external air filtration fundamental for cell culture.
The main aim of my PhD work is to develop and evaluate scalable process for the production of in vitro healthy and pathological models representative of cartilage tissue as platforms for testing novel pharmaceutical treatments. The relative objectives (OBJ) are:
OBJ1: To review the literature on current methods for the production and maintenance of in vitro healthy and pathological cartilage models and their lack to be filled;
OBJ2: To establish protocols for manufacturing in vitro cartilage tissue;
OBJ3: To develop scalable bioprinted processes for the generation of cartilage models in vitro and to assess the quality of the tissues and use them for further drug screening.
Background
The use of in vitro models is promising in increasing our understanding mainly on physiology, biology, and progression of diseases in order to be used as drug screening systems.In the last decade creating in vitro 3D tissue models, developed to a level in which living constructs, can closely mimic the native tissue environment in a high-throughput platform. Drug discovery is an inefficient procedure with a high failure rate and an extreme financial expense. From the compatibility point of view, studies on animals do not always are trustable in terms of results in human trials, and the regulatory environment is becoming stricter as time progresses. From the moral perspective, attempts should be made to reduce the number of animal studies conducted according to the 3R's principles (Replacement, Reduction and Refinement) based on a more ethical use of animals in testing. Although several fabrication techniques have been used to develop these models, 3D bioprinting technologies are advantageous owing to their low cost and efficiency, high throughput, excellent reproducibility, and ability to create complex geometries as the cartilage tissue. Currently cartilage tissue engineering strategies are insufficient for reproducing tissue that is equivalent to healthy and pathological cartilage. At the moment there has been greater interest in studying the zonal differences found in cartilage matrix and cellular composition and bioprinting presents an appealing tool for constructing stratified scaffolds, especially in patient-specific size and shape of individual lesions with control over spatial resolution, shape, and mechanical properties. Thus, it could be interesting to reproduce and compare 3D models of osteoarthritic and healthy cartilage tissue in order to validate in vitro new alternative treatments (i.e. drug screening).
Methods
I am going to use natural-based polymers, such as chondroitin sulphate or chitosan blended with gellan gum or alginate for comparing different bioinks properties with the aim of finding the best solution in terms of printability, cells viability and tissue formation. The selected biofabrication technique is an extrusion-based 3D Bioprinter, ROKIT Invivo which allows users to create versatile 3D cell-laden structures, multi-layered with different materials and extensive designs. The printing system is made of a polymer extruder, a biodispenser with controlled temperature in the range of -4-80 C and an hot pneumatic dispenser (up to 350 C). Synthetic biopolymer as well as various hydrogel for scaffold generation can be used and for this reason Rokit is an optimized tool for many biomedical research with its modular system and sterile environmental, because provided with a H14 grade Hepa filter for external air filtration fundamental for cell culture.