He joined the faculty there in 1992 and has focused his research efforts on the host response to bacterial pathogens and modulation of T cell responses to prevent deleterious host tissue disorders. His work was among the first to show that bacterial polysaccharides can elicit cell-mediated immune responses and can be used to modulate deleterious host tissue responses such as surgical adhesion formation. He has recently begun a program to develop novel conjugate vaccines for the prevention of diseases caused by Francisella tularensis, a Class A agent of bioterrorism. Currently, he holds two R01 NIH grants and is a project leader for New England Center for Regional Excellence for Biodefense and Emerging Infectious Diseases funded by the NIAID/NIH.