Hanging by a thread : Spin based fabrication of amelogenin for cultivation of osteoblasts

Abstract

Amelogenin is a protein which has been found to have many interesting properties. Its biological function is a key part in organizing the crystals of the enamel and it has been found to have a clinical use for periodontal regeneration. Its self-assembling properties also makes amelogenin a suitable material for the fabrication of biomaterials. The aim of this project is to investigate the possibility of using spinning based fabrication in order to make a filament out of amelogenin and to see if this filament is suitable for osteoblast cultivation.

Four amelogenin constructs were investigated in this work, rH146, rH174, AMGsol and AMGcell. The assembly process of all of the constructs were followed in order to see if they would produce fibrillars structures and only rH146 did, while the other constructs formed irregular clusters. However all construct as well as co-assemblies of AMGsol and AMGcell with rH146 were tested as spinning dopes for the filament fabrication. It was found that the most suitable constructs were made from rH146 that had been assembled for 24 hours. Most other spinning dopes failed to produce a filament.

Filaments made from rh146 were then put in 24 well plates and used to cultivate osteoblasts. These results were inconclusive. There were some indications that the cells could grow on the filaments, or at least the exposed parts, however due to the thickness and granularity of the filaments it was impossible to know for sure if the cells had attached.

Popular Abstract

In my degree project I have tried to make a string from teeth and then grow bone cells on it. Or not teeth exactly, there is a protein which helps build up and organize the enamel called Amelogenin. This protein has many interesting properties, for example it has been found to be a useful medicine when repairing bone and it can organize itself into larger structures.

Many different versions of this protein were tested. The first step was seeing if they would build themself into the larger structures mentioned above. Only one type of amelogenin was able to do this; a shorter version called rH146. This version quickly formed small needle like structures which over time formed into something looking more like wool or a bunch of fibers. After around 2 days the protein solution had become too vicious to handle properly and hence it was decided that the strings would be made from proteins that had been assembling themself for 48 hours or less. Making the strings was a success and it was discovered that the best strings were made from rH146 which had been assembled for 24 hours. At this point it was time for the next step, growing the skeleton cells on the strings. This led to problems however due to the fact that the strings were very thick and the cells were very small and see-through. The cells could grow around the strings but it was very difficult to see if they grew on top of them. However in places where the strings had broken or were thinner it seemed like you could see cells growing. So there needs to be more research and better ways to detect cells growing on the string.

Making a string from amelogenin is the next step on the road to making more complex materials and structures. If successful this could eventually lead to the ability to 3D print bone, making a scaffolding for cells to hold on to and improve the already successful medical treatments based on amelogenin. This project did not manage to definitively show that skeleton cells were able to grow on the strings, however the fact that it was possible to make a string which cells might have attach to is a good starting point for future research.

• author: Zedendahl Persson, Valdemar
• supervisor: Johan Svensson Bonde
• organization: Pure and Applied Biochemistry; Computational Chemistry
• course: KBKM05 20231
• year: 2024
• type: H2 - Master's Degree (Two Years)
• subject: Technology and Engineering
• keywords: Amelogenin, Biomaterial, molecular biotechnology
• language: English
• id: 9149701
• date added to LUP: 2024-03-14 08:50:34
• date last changed: 2024-03-14 08:50:34