A solution for spinal injury: A biomaterial that stabilises injured vertebra and stimulates new bone growth

In this project the PI Odd Höglund and postdoc Michael Pujari-Palmer will evaluate two new biomaterials that may be used to fuse vertebras. The collaboration combines Michael’s background in material science with Odd’s expertise in clinical science and access to animal tissues.

They first met at a networking event that was arranged by U-Share together with Uppsala University’s Junior Faculty and Future Faculty at SLU, with the aim to stimulate networking and increase collaboration.

“In our case this was a very effective meeting. Michael asked me if I could help providing tissues that he could use to test the biomaterials that he was studying. After the meeting we continued talking on the parking lot until it got very late and Michael told me about the materials in more detail,” Odd describes.

“Yes, one could say that we hit it off from the beginning,” Michael agrees.

Materials that improve healing of bone tissue and achieve fusion

The aim of their project is to develop and test new materials with properties that can improve healing both in animals and humans. The two materials that they are evaluating together are an osteostimulatory cement and a bone adhesive that can improve healing of bone tissue and achieve fusion based on the biological and regenerative properties of the material. The cement had already been implanted in animals to improve spinal fusions when Michael was recruited and he describes what he is doing now.

“For the cement, my role is to help develop the material that has been implanted. The first test results are coming now and the feedback that we get from the tests will be used to revise or improve the material. I also help out with other things that have to be done, like assisting at surgeries, preparing the materials and analysing the data.”

“These are experiments that take a long time but now we are at the stage where we are doing a lot of analyses,” Odd fills in. “Michael’s past experience will be very helpful for the tissue analyses, so it’s an excellent timing that he has started now.”

The second material is a novel bone tissue adhesive that is capable of fixating and improving the healing rate. The adhesive can also bond to cartilage tissue and this is tested on cadaver tissues in collaboration with an animal hospital in Gothenburg.

“We have initiated two orthopaedic studies with the adhesive and shortly Michael will have a lot of material to analyse,” Odd says.

The graph shows the force needed to separate surfaces of different materials that have been glued
using the adhesive. The bottom images show three types of tissues that are glued with the adhesive:
cartilage (b), tendon (c) and bone (d).
The figure is from the paper A novel class of injectable bioceramics that glue tissues and biomaterials.
Pujari-Palmer M, Guo H, Wenner D, Autefage H, Spicer, CD., Stevens, MM., Omar O, Thomsen P,
Edén M, Insle, G, Procter P, Engqvist H. Materials, 2018, 11(12), 2492.

Valuable access to animal tissues

Michael and Odd hope that their collaboration will be beneficial not only for them but that it could also inspire other groups at the universities. Michael explains how important the access to tissues and, later on, animals is for testing materials that are intended for eventual medical applications.

“Developing these materials is very costly in time and resources and the sooner you can test in a realistic model, for instance in fresh or living tissue, the sooner you can find out which of your efforts is worth the investment. Our analyses of the adhesive on cartilage, for instance, are ground-breaking studies that you can’t do if you don’t have access to the tissues. Even if we’re not testing live animals, just using the tissue that is available is a huge bonus. So, I think that when we form a stronger collaboration and knowledge transfer this can encourage other researchers at UU to contact Odd, or other SLU scientists, to form collaborations.”

Odd agrees: “Yes, it’s surprising that there previously has been so little use of the possibility to collaborate between the subjects we represent. Access to human tissues is for obvious reasons very limited but at SLU animal tissues are readily available, both from food producing animals and from privately owned pets that have been donated after they have been put down due to disease or old age. We also have access to facilities to study animals of all sizes. So, we should have so much more of these interactions.”

Increasing their network

The platform for preclinical PET-MRI at UU has new equipment for computed tomography (micro-CT) and a laboratory for preparing hard tissue structures for histology. Odd has contacted them about studying the bone that has been formed in the spinal fusion project.

“We still don’t know what the micro-structure looks like of the bone that has been formed to fuse the vertebras and we have discussed using the equipment at the platform. They are also interested in increasing the collaboration with SLU and I have introduced them to the pathology group and the bone research group at SLU,” he says.