БиоПро Выбор потребителя 2018 #01

The effectiveness of mesenchymal stem cells in the fight against implant-associated bone infections has been proven

Bone infections associated with implants are usually difficult to treat and require long-course antibiotic therapy. In a new study, researchers at Kanazawa University have found that infections like these can be effectively treated with a combination of antibiotics and stem cells.

Often, with fractures, implants are required to stabilize and effectively heal the broken bone. However, they can cause serious bone infection and the development of diseases such as osteomyelitis, which can only be treated with long-term antibiotic treatment. This, in turn, bears the risk of developing antibiotic-resistant bacteria.

While the international community is conducting large-scale research to find new types of antibiotics that can fight resistant bacteria, there is another way: studying the antimicrobial properties of stem cells.

One of the most promising and widely used types is mesenchymal stem cells (MSCs), which can be obtained from bone marrow or adipose tissue. One of the proven positive properties of MSCs is their antimicrobial action.

Adipose-derived [mesenchymal] stem cells, or ADSCs, have the distinct advantage of being abundant in subcutaneous adipose tissues and can thus be easily harvested”, – says the corresponding author of the study published in Scientific Reports Tamon Kabata. “The goal of our study was to investigate the therapeutic effects of ADSCs in combination with the antibiotic ciprofloxacin in an animal model of implant-related bone infection.”

At the start of the study, the researchers focused on studying the effect of ciprofloxacin on ADSCs and found effective antibiotic loading of ADSCs in the first 24 hours. However, ciprofloxacin did not have any side effects on the function or viability of mesenchymal stem cells.

The researchers then tested the antimicrobial activity of mesenchymal stem cells containing antibiotics in vitro and found that they were effective in reducing the proliferation of Staphylococcus aureus, which is also the main microorganism that causes infections associated with bone implants.

However, the question remained – will this new approach be able to prevent the spread of the infection caused by the implant in a living organism? The researchers tested this in rats that received bone implants using screws coated with Staphylococcus aureus.

Osteomyelitis developed in the rats 7 days after the operation. The researchers divided the animals into four groups. The first group was injected with ADSCs containing ciprofloxacin, the second – only ADSCs, the third – only ciprofloxacin, and the fourth, control, received no treatment.

Using microcomputed tomography to visualize the affected bones, the researchers also found that mesenchymal stem cells containing ciprofloxacin reduced the likelihood of osteolysis or bone degradation, which is important not only for bone health but also for the stability of the implant.

“These are striking results that show how ADSCs can efficiently be loaded with antibiotics to exert a strong antimicrobial effect. Our findings suggest a potential novel therapy for implant-associated osteomyelitis, for which conventional treatment with only antibiotics is usually insufficient”, – says Kabata.