A team of researchers at Washington State University, in Pullman, claims its producing exciting results in its work to develop bone implant materials for people suffering from bone-related problems, such as arthritis. It also is studying ways to use that technology to stop cancer from spreading.


Over the last two years, the team has received about $3.4 million in funding that includes a $750,000 grant this summer from the Los Angeles-based W.M. Keck Foundation, says Amit Bandyopadhyay, associate professor of mechanical and materials engineering and director of WSUs year-old Bioengineering Research Center. As a result of the Keck grant, WSU established the Biomedical Materials Research Laboratory, which is part of the Bioengineering Research Center.


Bandyopadhyay says he has been working with his wife, Susmita Bose, who also is a WSU professor, and Howard Hosick, a professor of molecular biosciences at WSU, on a number of projects since 1998. Those projects now are part of the newly-established research lab.


The focus of their investigations is on metal implants for load-bearing applications, such as hip replacements, and ceramic structures for non-load-bearing uses, such as vertebrae, he says. The major challenge with regard to metal implants is creating ones that are long-lasting, he says.


Back in the 1950s, when doctors began performing hip-replacement surgeries, the average lifetime of those implants was 10 years, Bandyopadhyay says. Patients could have one revision done on that implant, which could last an additional five to seven years, but couldnt have another total hip replacement. A half-century has gone by since those initial surgeries and that is still the case for people with hip replacements, he asserts.


If a patient gets a hip implant at age 80 and isnt active, then the short lifespan of the implant isnt really a factor, Bandyopadhyay says. But if a patient is 50 years old, physicians tell them to take pain killers for a few years instead of having their hips replaced right away, because the implant wont last very long.


He says the materials currently used for hip implants are denser than surrounding bone. That heaviness eventually weakens bones and endangers their bond with implants.


The team has been working on developing a lighter metal implant, made from porous titanium, that would be more flexible and would minimize damage done to the hip socket by the implant device, he says. They are hoping that such an implant will last much longer than current implants.


The team plans to use laser-engineered net shaping (LENS) technology to develop those porous metal implants, he says. During the LENS process, a laser creates a metal replica of a real bone using computed tomography and magnetic resonance imaging scans of that bone.


Its like an ink-jet printer for metal, he says. You could take a computer image of your coffee mug, print out an exact replica of that mug, and use it for your coffee.


Bandyopadhyay says money from the Keck grant is being used to buy the LENS machine so the researchers can prove their concept. The Virginia-based Office of Naval Research (ONR) has given them $2.25 million for that research over the past two years, because of its implications for national defense.


The ONR wants to know if the titanium materials used for implants in the human body can be adapted to help make aircraft and ships lighter and more fuel efficient, he says.


Creating absorbable materials


The other major project the team is working on involves bone-grafting materials that could be used for applications such as spinal reconstruction. The major challenge of that endeavor is to create materials that are absorbable, he says.


The team is developing materials they call ceramic scaffolds to help implants bond with human bone. Theyre creating those porous structures using nanoscale ceramic substances that would allow bone cells to grow into the implants and replace the scaffolds as the scaffolds dissolve into the body. He says the concept is similar to sutures that are placed in soft tissue to help it heal after surgery.


Were having a lot of exciting results in the research on ceramic scaffolds, Bandyopadhyay says.


The team has designed bones on a computer, has created plastic bone models, and has produced ceramic implants from those models. Currently, theyre focusing on tailoring those implants to have certain absorption characteristics, using a process Bandyopadhyay calls metal ion doping to replace calcium in those ceramics to make them more absorbable.


In the teams other sizable chunk of funding in the past two years, the U.S. Department of Defenses University Research Instrumentation Program gave the research center $400,000 to study those nanoporous materials. The Defense Department is interested in manufacturing those materials for military applications.


Hosick says his role as the biologist on the team is to study how bones react at the cellular level with those implants. He says cells produce certain proteins that make them sticky. If he can find out which proteins give cells that stickiness, he believes he can determine how those proteins help to fasten bone cells to ceramic surfaces.


That research has more implications for health care than bone implants and bone-grafting materials, Hosick says. The bone-implant technology being developed also has the potential to help manage cancer, he says. Hes working on a spinoff project that studies both bone cells and cancer cells.


When cancer cells metastasize, they break away from their primary site and travel through the bloodstream to attack other areas, such as bones. He says that if he can discover what makes cells stick to bones, then perhaps he can create a bone, using a ceramic implant, that will attract those cells during the metastatic process.


For instance, during surgery for breast cancer, if we can put up a ceramic blockade, then it would stop cancer from spreading, he says. The trick is to make sure cancer cells stick and other cells dont when trying to filter cancer out of the circulatory system.


Hosick says another approach would be to design a system similar to the one used during kidney dialysis. Blood could be drawn out of a patients body, run through a ceramic surface where the bad cells would be trapped, while the good cells would be infused back into the patients body.


Im proud of these ideas, because they could help manage breast and prostate cancer, among other cancers, he says.


The cancer cell project is still in its conceptual stages and hasnt received any dedicated funding, but Hosick says he has submitted a proposal for a $250,000 grant to the U.S. Department of Health and Human Services National Institutes of Health (NIH).


The WSU team currently is focusing on the cancer cell and implant projects, but may pursue other projects in the future, he says. That all depends on where their current studies take them, he says.


Theres an old saying that if you know where youre going with the research then its not really research, Hosick says. Were keeping our momentum up and always thinking of new approaches.


Hosick has been a professor at WSU since 1973, and Bandyopadhyay came to WSU in 1997. Bose also is a professor of mechanical and materials engineering.