Role of Natural Killer Cells in Chronic Toxoplasma gondii Infection

Natural Killer cells play in important role in the body's innate immune response to pathogens and tumors; however, they have also been shown to play a role in adaptive immunity by providing a memory response. In Toxoplasma gondii, infection is initially well controlled by the innate immune response, but is then allowed to reactivate about four weeks post infection. Parasite reactivation is most widely attributed to T-cell exhaustion during chronic infection. Due to the recent research showing that NK cells are important beyond the initial infection stage we hypothesized that NK cells also become exhausted and contribute to T. gondii reactivation. We demonstrate though, that NK cells do not become exhausted, but increase cytotoxic function and contribute to T. gondii reactivation.