Chronic Toxoplasma gondii infection curtails the cytotoxic potential of acute T cell responses to West Nile virus in the brain
Year: 2024
Type: preprint
Abstract: ABSTRACT Toxoplasma gondii (T. gondii) , a common brain-tropic parasite, chronically infects the central nervous system (CNS) of up to a third of the world’s population. Constant immune surveillance interrupts cyst reactivation within the CNS and dramatically alters the immune landscape of the brain. West Nile virus (WNV) is a mosquito-borne infection with a clinical spectrum ranging from asymptomatic to mild flu-like symptoms to severe neuroinvasive disease. In a cohort of WNV infected people, we discovered a positive correlation between WNV disease severity and T. gondii seropositivity. In a mouse model pairing chronic T. gondii with acute WNV infection, we found an increased susceptibility of mice to WNV, with reduced granzyme B expression in WNV-specific T cells and increased regulatory T cell (Treg) numbers in the brain, but not the periphery. This demonstrates that the T. gondii -infected tissue microenvironment impairs immune defense against other brain infections by blunting local T cell responses.
Institutions: University of Arizona, BIO5 Institute
Language: English
Subfield: Parasitology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W4391150751