The Freeman laboratory studies picornaviruses with tropism for the central nervous system using human tissue models (organoids) of relevant sites derived from induced, pluripotent stem cells. Our current focus is on how enterovirus D68 (EV-D68) mediates acute flaccid myelitis (AFM), a polio-like illness, in children by using a novel human spinal cord organoid model.

EV-D68 was responsible for widespread biennial outbreaks of severe respiratory viral illness in children from 2014-2018 as well as AFM. Transmission was disrupted due to non-specific masking and distancing efforts to control SARS-CoV-2 in 2020; however, EV-D68 circulation rebounded in late summer 2022. The expected peak in cases of paralysis, however, was not realized.

Current investigations include:

1. How does EV-D68 mediate acute flaccid myelitis?

2. What factors allow for entry of EV-D68 into the CNS?

3. What virologic or host differences were responsible for the lack of acute flaccid myelitis in the 2022 season, despite significant viral circulation?

Dr. Freeman is a physician-scientist with training in virology, cell biology, and organoid biology and her lab modulates each of these factors to better understand host-pathogen interactions that contribute to CNS-tropic picornavirus infections.