Montaner studies the mechanisms of disease in HIV-1 infection and cancer, exploring new strategies to boost the natural function of the immune system in order to combat viral-associated disease or cancer progression.

Montaner obtained his D.V.M., Veterinary Medicine from Kansas State University in 1989 and his D.Phil. in Experimental Pathology from University of Oxford, Oxford, U.K., in 1995. He joined The Wistar Institute in 1995 as an assistant professor and was promoted to professor in 2007.