Dr. Anjan Debnath, Ph.D., M.A.S.

My research interests can be categorized into two broad areas: (1) Development of new antimicrobials for parasitic diseases. Amebiasis, giardiasis Primary Amebic Meningoencephalitis (PAM) and Acanthamoeba keratitis, caused by the protozoan pathogens Entamoeba histolytica, Giardia lamblia, Naegleria fowleri (brain-eating ameba) and Acanthamoeba castellanii continue to be the major causes of morbidity and mortality. Colitis and diarrhea are the most common manifestations of amebiasis and giardiasis and PAM contributes to extensive inflammation and hemorrhage of the brain. Acanthamoeba keratitis is a painful eye infection that can lead to blindness and occurs in healthy individuals wearing contact lenses.

My research on drug discovery uses a two-pronged approach, combining a strategy of repurposing compounds that are already in clinical development along with development of compounds with novel scaffolds and improved activity against the parasites. This approach encompasses both robotic-driven technology and close interaction with multiple academic groups, pharmaceutical company partners and non-profit organizations. This aligns well with the mission of the Center for Discovery and Innovation in Parasitic Diseases (CDIPD), which is to discover and develop drugs for neglected parasitic diseases.

(2) Studies on molecular mechanism of pathogenesis. E. histolytica, N. fowleri and Acanthamoeba are remarkable organisms with phagocytic and proteolytic capabilities, invading colonic mucosa, human brain and eyes. We are using these model systems to identify or validate key virulence factors contributing to colonic, brain, and eye infections. In addition, we are using designed small molecule inhibitors to probe the function of important proteins, such as cysteine protease, heat shock protein 90, thioredoxin reductase, steroidogenic enzymes in Entamoeba, Naegleria and Acanthamoeba biology. These studies are providing important new clues about how a pathogen orchestrates responses to the host environment and the knowledge generated in these studies has the potential for generating new types of therapeutics for the treatment of amebiasis, PAM and Acanthamoeba keratitis.