Preconditioned cells may help heal major bone fractures
While the body can fix small bonebreaks withrelative ease, more significant injuries such as large bone defectsor fractures are a little more tricky, often requiring some extrahelp to mend. Now, scientists from KU Leuven in Germany are improvingthe effectiveness of treatments to deal with those more serioussituations, preconditioning cells before implantation, allowing themto better deal with the often inhospitable environments at woundsites.
One way to help larger bone wounds toheal is to implant bone cells at the site of the break, that can helpfacilitate and speed up the process. Unfortunately there's one bigproblem with such a treatment – the cells encounter an inhospitable environment when implanted, with damage to thesurrounding cells causing an insufficiency of oxygen and nutrients.
It takes significant time for new bloodvessels to reach the implanted cells, and with the lack of keyresources, the new bone cells begin to produce harmful oxygenradicals, further complicating the situation. These difficultconditions cause as many as 70 percent of implanted cells to diewithin just days.
Addressing that exact problem, a teamof researchers at KU Leuven decided to try and equip the bone cellswith the means to better cope with the inhospitable environment. Todo so, they switched off an oxygen sensor known as PHD2, which inturn caused a dual defense mechanism to activate.
In this "survivalmode" state, the cells start stockpiling glycogen for use asemergency fuel, while using an amino acid called glutamine toincrease levels of antioxidants. According to the researchers, thechange can be made either through genetic engineering, or byadministering therapeutic molecules.
The method was successfully tested inlaboratory mice, allowing the cells to weather the harsh conditionsat the wound site by supporting themselves, generating energy unaidedand protecting themselves against increased levels of oxygenradicals.
"Reprogramming bone cells obtainedfrom patients might increase survival rate from 30 percent to 60percent, which will ultimately lead to better bone regeneration,"said study member Professor Carmeliet. "In future research, we willexamine whether this technique also works in even larger bone defectsand by using human cells."
The findings of the work are publishedonline in the journal Cell Metabolism.
Source: KU Leuven