by Danielle Bradshaw from In The Cloud Copy

Bone grafts, although very helpful, can result in hard to treat infections and typically result in the patient needing to be put on a lengthy antibiotic regimen. A recent study conducted by researchers at Kanazawa University showed that bone infections that come from implants can be treated effectively with a treatment that combines antibiotics and stem cells infused with antibiotics.

What Are Bone Implants and What Are the Risks?

When a bone fractures, it often calls for the use of implants so that the break can stabilize and properly heal. The problem is that in trying to heal the fracture, the implants can cause infections in the bone. Osteomyelitis, an infection of the bone marrow that can spread into the bloodstream, is one such illness that can be caused by bone implants.

The major problem is that osteomyelitis and other kinds of bone infections can only be treated with the long-term use of antibiotics. If you use a particular kind of antibiotic long enough, it can end up enabling the creation of bacteria that are resistant to it.

Trying to Find Solutions

Steps are being taken to make antibiotics that can take on this antibiotic-resistant bacteria; one such method researchers have investigated was to study how stem cells react to antibiotics. Mesenchymal stem cells, which can be found inside of both bone marrow and adipose tissue (fat), are just one of these types of cells and it’s been proven that they (and other kinds of stem cells) have antimicrobial qualities.

Tamon Kabata, the researcher that wrote the study, says that adipose-derived stem cells, or ADSCs, are particularly easy to obtain because they can be found inside of adipose tissue that lies under the skin. He says that they conducted their study to find if ADSCs’ have any sort of curative effect when used in concert with ciprofloxacin on bone infections made by implants inside an animal model.

The Study

The first thing that the research team did was to take a look at how the ciprofloxacin antibiotic affected the ADSCs. They saw that in the first 24 hours, neither the cell’s functionality nor viability was negatively impacted by the antibiotic drug. Next, the team tested how much antimicrobial activity the antibiotic dosed stem cells displayed inside of a tube. What they observed was that the ADSCs reduced the growth of bacterium S. aureus, one of the major microbes that causes implant-related bone infections.

The team was left wondering if they could take this discovery further. They wanted to know if the new method they’d found could also lesson infections inside of still-living organisms. To find out, rats were given bone implants that had screws with S. aureus swabbed onto them. Seven days after the implantation, the rats contracted osteomyelitis and from there the research team gave the rats one of four treatments:

• ADSCs that contained ciprofloxacin
• Ciprofloxacin without ADSCs
• ADSCs without ciprofloxacin
• No treatment

Osteomyelitis’ tendency to cause inflammation and abscesses in soft tissues was taken into account and so the researchers used the reduction of these symptoms as proof that ADSCs that contained ciprofloxacin was the only viable treatment. The infected bones were viewed by the team and they saw that the ADSCs that had ciprofloxacin inside of them were the only treatment given to the rats that reduced the osteolysis infection or deterioration of the bone itself. This can result in healthier bones and better stabilization of the implant.

Kabata says that the study shows that ADSCs that are infused with antibiotics can have a powerful curative effect and that the research he and his team conducted demonstrates that a possible new form of therapy for osteomyelitis caused by bone implantation may have been found.