Fellowship Director (Digestive Diseases)
Dr. Assis received his M.D. from Jefferson Medical College followed by internship and residency at Thomas Jefferson University Hospital in Philadelphia, where he was also Chief Resident. He completed training in gastroenterology and hepatology fellowship under the T32 research track at Yale followed by transplant hepatology fellowship also at Yale.
His clinical and research interests are focused in autoimmune and cholestatic liver diseases. Specifically, he treats patients with autoimmune hepatitis, primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) at his liver clinic. He performs translational and basic research on autoimmune hepatitis, PSC, and PBC using human biospecimens in addition to work with animal models. He is investigating the link between the pro-inflammatory cytokine macrophage migration inhibitory factor (MIF) and autoimmune hepatitis, and the effect of psychological stress on autoimmune hepatitis. He is also studying human bile-derived organoids, and their interaction with T-cells, to elucidate the pathophysiology of PSC and identify novel therapeutic approaches. He is active in the American Association for the Study of Liver Disease (AASLD), as current co-chair of the writing group on Guidance for PSC, and former member of of the writing group on Guidelines for autoimmune hepatitis.
In addition to this work, Dr. Assis is an active member of the Adult Cystic Fibrosis Program at Yale. In this role, he evaluates and treats patients with Cystic Fibrosis who have GI or liver complications of their disease. He consults on patients from outside Yale's Cystic Fibrosis program who have these complications. He also performs clinical research on Cystic Fibrosis liver involvement and is active in the Cystic Fibrosis Foundation.