Macrophage cells are the frontline soldiers of the immune system, appearing on the scene early on to protect the body from foreign invaders. These cells answer the immune system’s critical question for the rest of its troops: friend or foe?
As critical responders, macrophages may perceive useful biotechnology as a threat. If not created with the proper materials or mechanical forces, these devices can trigger an immune response that can cause inflammation, scar tissue, or device failure.
But what is the right material or the right mechanical strength? In a meta-analysis co-led by Dr. Abigail Clevenger, a graduate student in biomedical engineering at Texas A&M University, the researchers emphasize that context matters.
“No single force does the same thing to macrophages everywhere in the body,” said Dr. Shreya Raghavan, co-author and assistant professor of biomedical engineering. “For example, your lung inflates and deflates, so the macrophage in the lung is already accustomed to those forces and has some adaptations to those mechanics. But what a macrophage in the lung adapts to is different than what a macrophage adapts to in the lung. a macrophage in the uterus or intestine adapts.”
Clevenger, now a postdoctoral fellow, co-led the paper with Dr. Aakanksha Jha, a postdoctoral fellow at the University of Maryland. Jha’s advisor, Dr. Erika Moore, was also lead author of the study. The article, published in Trends in Biotechnology, highlights the need to understand macrophage cell behavior to potentially open doors to new or improved biotechnology and targeted immunotherapy treatments.
“When designing immunotherapy for colorectal cancer, for example, you can’t just design a solution in a dish where there are no mechanisms,” Raghavan said. “The mechanics change the way macrophages behave. Their design solutions must take into account that these are mechanosensitive cells. The consequence of not doing so means that the same macrophages that can help the devices work in the body also “They may perceive harmful tumors as friends and allow them to spread.”
According to Raghavan, the review critically summarizes the advances in research findings on interactions between biotechnologies and macrophages over the past four years.
“We felt there was a critical mass in scientific advancement and we were excited to bring it together,” he said. “Even five years ago, this was a significant knowledge gap, but with integrated tools between biomedical and tissue engineering and molecular and computational biology, there is a lot more data. It’s beautiful.”
In a more personal application, Raghavan uses a continuous glucose monitor that he turns off every two weeks due to the immune system’s response to foreign materials, eventually making the readings unreliable. He hopes that the knowledge gained through the review article can help his lab better determine steps to adjust medical devices, such as continuous glucose monitors, to improve immune response.
“It’s not a one-size-fits-all solution; you have to take everything in context, but that’s the power and beauty of engineering,” Raghavan said. “You can break it down and study the fundamentals, and then rebuild it in complexity.”