|“The body relies on stem cells to differentiate into bone cells that can heal broken bone tissue,” Brunski says. “When doctors use a synthetic implant, they are looking to damage stem cells as little as possible. We are looking for types of implants that do no harm to these important stem cells, and which might actually trigger stem cells to differentiate into bone sooner, speeding the healing process.”
Previous studies have revealed that certain mechanical signals can actually activate bone stem cell differentiation and growth. Brunski is looking at how the mechanical loading of an implant may be controlled to guide stem cell differentiation. Along with a collaborative team of researchers at Rensselaer and at Stanford and the University of Montreal, he has developed specialized implants that were placed in mouse bones. Their studies have shown that varying the loading of the implant and the implant’s shape can significantly change the rate of stem cell growth around the implant.
“Implants that stimulate stem cells to heal bone are particularly important for the elderly,” Brunski says. “As a person gets older, stem cell production is reduced at places of healing, making the healing process painstakingly slow. If we can use implants that speed that process, we could greatly improve lives post-surgery.”
While many in the burgeoning world of biotechnology are working to develop medications that foster stem cells, Jonathan Dordick, the Howard P. Isermann ’42 Professor of Chemical and Biological Engineering, has developed a high-throughput screening platform that will help scientists develop drugs that both grow and kill stem cells in the body.
“New research is showing that some stem cells could be the precursor for cancer and the reason that cancer reappears after having been totally eradicated by chemotherapy,” Dordick says. “With this platform we may be able to rapidly screen new drug candidates that target and kill these cancer stem cells. Instead of going for the mature liver cell that spreads cancer, we can catch a liver stem cell before it can kick off cancer development.”
The device is a form of lab-on-a-chip that condenses many experiments onto one small device, increasing the speed and efficiency of modern scientific and medical research. The one developed by Dordick and his team allows them to prepare up to 1,000 stem cell samples that are as small as 20 nanoliters on one chemically modified slide making it possible to complete 1,000 experiments at the same time.
The device will enable drug researchers to quickly screen thousands of small molecules (the basic element of many modern drugs) for their effects on the differentiation of stem cells. Once a molecule is found that has the desired impact on the stem cells, it can be isolated and further investigated by the lab.
With the number of Institute researchers and students working on stem cell projects likely to increase in the coming years, more breakthroughs like Dordick’s are sure to follow. The variables remain the funding and public support for further study. In the meantime, Rensselaer researchers forge ahead to the future. “Our scientists are filling a vital niche in the global scientific effort to develop medical therapies and new technologies using stem cells,” Palazzo says.