Kappes' research focuses on chromatin biology, epigenetics and tumor biology. He is especially interested in how the unique chromatin-associated oncogene DEK, a long-standing interest in the laboratory, participates in and regulates these processes. His teaching interests at Duke Kunshan include molecular biology, cell biology, epigenetics and biochemistry.

He has authored over 30 papers relating to DEK biology, some of which appeared in leading academic journals including PNAS, Genes & Development and Nature Communications. Besides his passion for research and teaching, he has been very active in academic administration and the promotion of learning and teaching. He acted as the chair of the Departmental Teaching & Learning Committee and was the inaugural associate dean for learning and teaching in the School of Science at Xi'an Jiaotong-Liverpool University (XJTLU).

Kappes has a "Diplom" (combined BSc and MRes) in molecular biology from the University of Konstanz, Germany, where he also completed his Ph.D. studies and first postdoctoral experience under the guidance of Rolf Knippers. He then joined the laboratory of David Markovitz at the University of Michigan Medical Center in Ann Arbor, U.S., for his second postdoctoral phase. In 2011, he returned to Germany to establish his independent laboratory at the RWTH Aachen University at the Institute of Biochemistry and Molecular Biology. Before joining Duke Kunshan, he was an associate professor at XJTLU.