Use of Human Neurons Derived via Cellular Reprogramming Methods to Study Host-Parasite Interactions of Toxoplasma...

Toxoplasma gondii is an intracellular protozoan parasite, with approximately one-third of the worlds' population chronically infected. In chronically infected individuals, the parasite resides in tissue cysts in neurons in the brain. The chronic infection in immunocompetant individuals has traditionally been considered to be asymptomatic, but increasing evidence indicates that chronic infection is associated with diverse neurological disorders such as schizophrenia, cryptogenic epilepsy, and Parkinson's Disease. The mechanisms by which the parasite exerts affects on behavior and other neuronal functions are not understood. Human neurons derived from cellular reprogramming methods offer the opportunity to develop better human neuronal models to study T. gondii in neurons. Results from two studies using human neurons derived via cellular reprogramming methods indicate these human neuronal models provide better in vitro models to study the effects of T. gondii on neurons and neurological functions. In this review, an overview of the current neural reprogramming methods will be given, followed by a summary of the studies using human induced pluripotent stem cell (hiPSC)-derived neurons and induced neurons (iNs) to study T. gondii in neurons. The potential of these neural reprogramming methods for further study of the host-parasite interactions of T. gondii in neurons will be discussed.