Immune System Remains an Unending Source of Fascination for Dr. Cheryl Rockwell

By Chuck Carlson

Dr. Cheryl Rockwell is enthralled by the body’s immune system. She explains her fascination with the complex system in a wonderfully down-to-earth way.

“It’s a really complicated system, and it interacts with every other organ system in the body,” she said. “I consider it to be a dramatic system because it has so many different players. It’s like a little military with lots of different personalities. You have the T-cells (which protect the body from infection), who are like the field generals. And you have the First Responders which are the neutrophils (the white blood cells which are the body’s first line of defense). Then the macrophages (white blood cells that stimulate other immune system cells and kill microorganisms) come in right after the neutrophils, and they make a lot of decisions on the field on their own, some of which are good and some of which are misinformed.”

Then she pauses and smiles.

“I find all these little different cell personalities fascinating.”

That, in a nutshell, is the immune system. And while Dr. Rockwell offered a layman’s explanation of how it works, her years of research as a food toxicologist in the MSU Pharmacology & Toxicology Department have shown how mysterious, complicated, and misunderstood it remains.

“Immunology is really interesting because it’s a younger science,” she said. “We’re further behind studying the immune system compared to others and that’s because we didn’t know what it was.”

Though the immune system was first studied as early as the 1790s, major advances regarding how it works and what it does really started happening in the 1960s when we learned the importance of lymphocytes and how they protect the body. Technological advances allow for more complete testing in vitro (in test tubes and petri dishes, for example) as opposed to in vivo, (testing on live animals). Since then, discovery and research has expanded exponentially.

Dr. Rockwell’s interest was sparked as a biology major at the University of Michigan, and when she began her search for a school to earn her Ph.D., she took the advice of a pharmacologist when he asked what she was interested in.

“I described to him how I wanted to work for a drug company, and I was really interested in more applied aspects of how those could be used therapeutically,” she said, “And he said, ‘You really don’t sound like a chemistry student, you sound like a pharmacology student.’ I realized he was right.”

Dr. Rockwell, a native of Grosse Ile, Mich., went on to earn her Ph.D. in Pharmacology & Toxicology from MSU in 2005, did postdoctoral work at the University of Missouri-Kansas City and the University of Kansas Medical Center. She has been on the faculty in Pharmacology and Toxicology at MSU since 2011, she is also a member of the MSU Institute of Integrative Toxicology. Her research has focused on xenobiotics, or substances foreign to the human body, such as food additives.

She said xenobiotic sensors likely play a crucial role in preventing exaggerated immune responses, thus protecting against autoimmunity and inflammation. Understanding these mechanisms can help develop new treatments for immune-related conditions.

As well, Dr. Rockwell studies the impact of exposome, or the total of environmental exposures a person experiences throughout their life, and how those exposures impact their health and biology.

She said while the body has evolved to co-exist with chemicals, food allergies brought on by chemicals remain a puzzle. “We really don’t have great tests for determining all these different possibilities,” she said. “The gold standard now for diagnosing food allergy is to bring your child into the doctor’s office, and they challenge them with the allergen to see if they have a response. We’d like to have better diagnostics.”

And that’s one of the challenges she enjoys. She recalled when she worked previously in a lab measuring environmental contaminants in air, water, and soil samples. The results, she found, were rarely a surprise.

Now, as she works with the immune system that continues to fascinate and test her, the answers are never simple.

“I need to find things not to work sometimes,” she said. “Because that brings the new questions, and that’s what makes it interesting. It’s the unpredictability of it.”