My interest in research began while an undergraduate and was enhanced at NYU medical school. Following internship, I entered the biochemistry Ph.D. program at MIT. In 1966, I joined the NIH and embarked on the study of poxviruses, which enabled me to combine my interests in science and medicine. In the 1970s I discovered the cap structure present at the ends of most viral and cellular mRNAs and characterized the viral and cellular biosynthetic enzymes. My laboratory purified the enzymes for vaccinia virus gene expression and DNA replication, discovered the hairpin structure linking the two strands of the poxvirus genome, determined the organization of the genes and regulatory sequences and discovered the first viral immune evasion gene. My most widely known contribution is the genetic engineering of poxviruses as expression vectors in the early 1980s and the demonstration of their potential use as vaccines to prevent infectious diseases and treat cancer. This work stimulated the development of other viruses as vaccine vectors. During my long career at NIH and affiliation with the University of Maryland, I have enjoyed mentoring numerous graduate students and postdoctoral fellows. Currently I am an NIH Distinguished Investigator and Chief of the Genetic Engineering Section.

Research Interests

I continue to study the biology of poxviruses with particular interest in virus-host interactions, virus entry and virion assembly. In addition my laboratory is using poxvirus vectors to study immunity to SARS-CoV-2 in transgenic mouse models.

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Primary Section

Section 44: Microbial Biology