A new study has found that Toxoplasma gondii, a parasite found in cat feces and undercooked meat, can be used as a delivery system for proteins that target neurological disorders. This engineered version of the parasite successfully targeted protein dispersal, opening up possibilities for new treatments. While these methods are not entirely new and additional research is needed, experts believe this approach holds promise. T. gondii infects about one-third of the global population and can remain in a host’s brain throughout their life without causing serious health issues.
Researchers injected mice with genetically altered parasites to deliver proteins into cell nuclei. They identified three basic methods the parasite uses to secrete proteins and found that their engineered version could utilize two of these simultaneously. This delivery system successfully secreted MePC2, a protein associated with a neurological disorder called Rett syndrome, highlighting the potential to target other neurological disorders using the parasite. The study emphasized the difficulty of targeting neurons with existing methods and the potential of T. gondii as a research tool due to its ability to deliver intracellular proteins to neurons.
Jasmin Dao, MD, PhD, a pediatric neurologist, noted that T. gondii typically causes mild symptoms in humans but has robust methods of survival once inside a host. The parasite can manipulate host cell machinery to enhance its proliferation and reduce immune responses. Researchers saw an opportunity to utilize T. gondii’s ability to target certain proteins with known utility in neurons due to its efficient binding to the central nervous system. The parasite’s three organelles for protein secretion suggest a strong chance of successful targeting for neurological disorders.
The study’s results highlight the potential for using T. gondii to deliver therapeutic proteins to brain cells, offering a novel approach to treating neurological disorders caused by specific protein deficiencies. Dao explained that targeting brain cells is challenging due to the blood-brain barrier’s protective layer, which regulates the passage of drugs and other substances into the brain. Using the parasite to inject therapeutic proteins directly into brain cells could benefit conditions like Fragile X or Duchenne Muscular Dystrophy, where specific protein deficiencies are involved.
Neurologist Santosh Kesari, MD, PhD, stated that while similar techniques using microorganisms for medical purposes have been utilized for decades, the use of engineered T. gondii is still in the early stages of research. FDA-approved modified agents, such as herpes virus for melanoma and adenovirus for bladder cancer, have been used for treatment, but many others are still in clinical development. Kesari highlighted the need for further research to optimize the engineered parasite for specific applications and ensure safety before human clinical trials. Concerns include the potential for the parasite to cause side effects in humans and the need to engineer safety features to control its effects.
