VCU and VSU researchers are studying marijuana use and the immune system

Two scientists conducting medical research in a laboratory.
Larry Keen, Ph.D. and Antonio Abbate, M.D., Ph.D. in the lab. (Photo by Tom Kojcsich, University Marketing)

While working with HIV-positive patients at an infectious diseases clinic in Jacksonville, Florida, Larry Keen, Ph.D., met many people who used marijuana to treat pain. “They would roll a joint while on pain medication,” Keen said. “I was like, ‘You never worry about how the marijuana and pain meds are interacting?’ And they looked at me and were like, ‘Why?’”

The question seemed obvious to Keen, who was at the University of Florida on a postdoctoral fellowship funded by the National Institute on Drug Abuse. His research on immune function and neuropsychological performance among people in the African American community often converged toward a widely used but scarcely researched substance — marijuana.

“The study of marijuana use is still burgeoning, which is weird to me because it has been around for thousands of years,” he said.

After completing the fellowship, Keen joined Virginia State University in 2014 as an assistant professor of neuropsychology and psychoneuroimmunology, which is the study of the interaction between psychological processes and the body’s nervous and immune systems. He continued the marijuana research while leading the Psychoneuroimmunology of Risk and Disease Laboratory, where he noticed an association between marijuana use with leukocyte activity and cytokine production in the human body. Both parts of the immune system, leukocytes are white blood cells that help the body fight disease and cytokines are small proteins released by immune cells to help them communicate with one another. Keen found that both played a role in systemic inflammation, but the exact relationship between marijuana use and the immune system markers was not clear.

Energized by his small discoveries and eager to learn more, about two years into his tenure at VSU Keen started to apply for grant funding to explore further his area of research. However, much of the feedback he received took on a familiar tone.

“I got reviews back saying, ‘The guy is kind of cool, but he doesn’t have the resources at his university to carry the work out,’” he said. “They told me I needed collaborators, so I took that to heart and I started looking.”

Knowing that a major research university was just 30 miles north of the VSU campus, Keen started his search for collaborators on Virginia Commonwealth University’s website. “There was no one at VSU who was doing anything close to what I was doing with substance use, immune function and cognition,” he said. “I needed mentorship.”

Larry Keen, Ph.D. and Antonio Abbate, M.D., Ph.D.
Abbate and Keen hope their partnership — created by an NIH grant — paves the way for further collaboration between VCU and VSU. (Photo by Tom Kojcsich, University Marketing)

Browsing through VCU faculty profiles, Keen found cardiology professor Antonio Abbate, M.D., Ph.D. Among other things, Abbate researches inflammation. Keen emailed and to his surprise, Abbate responded, inviting Keen to a meeting at the VCU C. Kenneth and Dianne Wright Center for Clinical and Translational Research. The meeting focused on developing strategies for recruiting participants to a community-based substance-use disorder study. 

“That was something I could help with,” Keen said.

A mentoring relationship soon developed between Abbate and Keen. Abbate, an associate director of the Wright Center, takes a special interest in mentoring students and junior faculty members. In February, he was presented with the inaugural Thames-Kontos Mentoring Award from the VCU School of Medicine and in May, he was given the VCU Undergraduate Research Opportunities Program Faculty Mentor Award. In 2016, the School of Medicine honored him with the Distinguished Mentor Award.

“He took an interest in mentoring me and was like, ‘What do we need to do to get you where you want to go?” Keen said.

The pair continued to collaborate and in late 2018 Abbate suggested that Keen apply for a Research Supplement to Promote Diversity in Health-Related Research, which was awarded to the Wright Center by the National Institutes of Health’s National Center for Advancing Translational Sciences. The Wright Center is eligible for the supplement as a member of the Clinical and Translational Science Awards Program, a national consortium of more than 50 research institutions that are accelerating the transformation of laboratory discoveries into treatments for patients.

“We mapped it out, bounced a couple ideas around for maybe a week, and then we started writing and that was it,” Keen said.

Keen was awarded the research supplement in May, enabling him to devote 75 percent of his time to training and research activities for two years.

“I have been at VSU for five years now and I am building my own thing there, but the research supplement gives me an opportunity to expand my expertise,” he said.

The supplement supports a pilot study that Keen will lead investigating the complex interplay among marijuana use, brain activity and the immune system. “This is the first pilot study I will be able to do where I can look at a complete picture of how chronic marijuana use affects a variety of bodily systems, including leukocyte and cytokine activity,” he said.

Larry Keen, Ph.D. and Antonio Abbate, M.D., Ph.D.
Keen, left, will lead an investigation into the complex interplay among marijuana use, brain activity and the immune system. “This is the first pilot study I will be able to do where I can look at a complete picture of how chronic marijuana use affects a variety of bodily systems," he said. (Photo by Tom Kojcsich, University Marketing)

Keen will conduct research at the Wright Center’s Collaborative Advanced Research Imaging facility with a sample of 50 people who live in the Richmond metropolitan area, half of whom have marijuana use disorder. In addition to working with faculty members and students from the MCV and Monroe Park campuses, Keen will enlist VSU graduate and undergraduate students to help with the research.

“Being able to partner with VCU in this way gives my students exposure to lab work and MRI research,” he said, adding that he hopes the partnership paves the way for further collaboration between the two institutions.     

The supplement also provides Keen with opportunities to expand his expertise through coursework and career development activities. Over the next four semesters, Keen will enroll in VCU courses on topics including immunobiology, scientific integrity and responsible scientific conduct. He also will attend monthly Wright Center Clinical Research KL2 Scholar meetings.

He hopes the training program prepares him to be more of an independent investigator.

“This work is building me to the point where the NIH and other agencies will see me as an expert and will fund my research,” Keen said. “In order for me to be an independent investigator, I need to pay my dues. I need to publish, work on smaller developmental grants, and build a collaborative network that shows that I am supported. It is funny how having more of a team makes you more independent.”