Toxoplasma gondii evokes a strong innate and adaptive immune response in the host.

Innate immunity to the parasite is comprised of many components like DC, neutrophils, macrophages, inflammatory monocytes, and NK cells.

CD4 T cells (Toxoplasmic encephalitis) play an important helper role in the maintenance of long-term CD8 T cell immunity.

CD8 T cells (Toxoplasmic encephalitis) control chronic infection by IFNg and cytotoxic activity.

In an encephalitis model of infection, CD8 T cells undergo exhaustion due to increased expression of inhibitory receptors.

Toxoplasma gondii is an obligate intracellular parasite that can cause severe complications in the newborn and immunocompromised individuals. The parasite evokes a strong innate immune response in the infected hosts which is followed by a robust adaptive immunity. In the last few years, importance of innate immune mechanisms dependent on the role of MyD-88 independent pathways, inflammatory monocytes and innate lymphocyte have been identified. However, notwithstanding the strong immune response to the parasite, the chronic infection persists in the host. The inability to prevent chronic infection can be attributed to aberration in the memory CD8 T cell response caused by an increased expression of inhibitory receptors that leads to their dysfunctionality.

© 2022 Published by Elsevier Ltd.