Tessier joined the Rensselaer faculty in 2007 following an American Cancer Society postdoctoral fellowship at the Massachusetts Institute of Technology's Whitehead Institute for Biomedical Research. He received his bachelor's degree in chemical engineering from the University of Maine and went on to earn his doctoral degree in chemical engineering from the University of Delaware. His research aims to understand the misfolding of proteins into toxic protein particles in Alzheimer's disease and related disorders with the long-term goal of preventing, reversing, or redirecting this deleterious misfolding behavior.