Optimizing immunity against toxoplasmosis by using exosomes released from Toxoplasma gondii tachyzoites, bradyzoite cysts, and infected host immune cells 2614

Abstract Description Toxoplasma gondii is an apicomplexan parasite causing infection through contaminated food or water. Acute infection is characterized by fast replicating tachyzoites that differentiate into dormant bradyzoites. There are no viable vaccines for humans and therapeutic strategies can lead to damaging side effects. Developing an ideal vaccine remains a significant challenge due to the complexities of the T. gondii life cycle. Previous research shows partial immunity in mice from exosomes released by tachyzoites. Exosomes are extracellular vesicles (EVs) essential for cellular communication. Although previous studies have shown partial immunity, we aim to investigate if secretion from tachyzoites, bradyzoites, and T. gondii-infected immune cells could lead to long-lasting protection. To test this, we isolate EVs from both type II T. gondii life stages and infected immune cells, verifying them with vesicle surface marker CD63 and life stage-specific proteins (SAG-1, CST-1) via Western blot and microscopy. Nanoparticle tracking analysis will further confirm EV extraction by analyzing vesicle size. After extraction, uninfected immune cells are co-incubated with EVs to assess cytokine levels through ELISA. Additionally, C57BL/6 mice will be immunized intramuscularly with EVs before infection, with survival, antibody, and cytokine levels monitored post-infection. This study will expand knowledge of therapeutic potential for T. gondii-secreted exosomes in immunity against toxoplasmosis.? Topic Categories Microbial, Parasitic, and Fungal Immunology (MPF)