Theodora Hatziioannou

Theodora Hatziioannou is a Greek-American virologist. She known for her work discovering restriction factors that counteract HIV-AIDS and other primate lentiviruses, thus restricting them to specific species, and making it hard to study HIV-1 in animals. Her findings allowed her to develop the first HIV-1-based virus which is capable of recapitulating AIDS-like symptoms in a non-hominid (in this case pigtail macaques). She is a Research Associate Professor in the Laboratory of Retrovirology at The Rockefeller University in New York. She is a co-author of a textbook on virology, Principles of Virology.

Early life and education

Theodora Hatziioannou was born and raised in Rhodes, Greece. She studied biochemistry at the University of Bristol in Britain and then got a Master's degree in biotechnology from Imperial College London. She worked as a research technician with Robin Weiss at the Institute of Cancer Research, where she says she fell in love with research and determined she wanted to go on to earn a PhD. She therefore moved to Lyon-France, where she earned a PhD from the University Claude Bernard in 1999. Her PhD research, carried out under François-Loïc Cosset, involved looking at adapting retroviruses to use as tools for gene therapy, seeking to expand their tropism and target them to specific cells by manipulating the retroviral envelope. In 2009, she demonstrated that swapping out just the Vif gene allowed HIV-1 to infect pigtail macaque monkeys, whose TRIM5 they (and others) had found didn't bind to the HIV-1 capsid. This modified virus still contained 96% of the HIV-1 genome, making it a major advance over SIV models, however it did not cause illness in the monkeys . In order to develop a model recapitulating human AIDS, they temporarily depleted the immune systems of pigtail macaques and then serially passaged the virus through these monkeys, allowing it to adapt to better grow in pigtail macaques. After multiple passages (using virus grown in one monkey to infect another), the virus gained strength to the point that the monkeys showed classical signs of AIDS including depleted CD4+ T-cells (the type of immune cell lost in AIDS). This was the first time scientists had been able to cause AIDS in primates, and provides a more relevant animal model for research than any previously available. These pseudoviruses could be worked with at a lower biosafety level than SARS-CoV-2, making it easier for researchers to study and measure neutralizing antibodies.

Personal life

Hatziioannou is married to the virologist Paul Bieniasz, with whom she frequently collaborates. The couple have two children.

Key publications