While single exposure to 100 μg/mL GSPL for 24 h post-infection, reduced the intracellular parasite load to virtually zero (4.52±1.0 parasites/1000 adherent cells), 1 h pre-treatment with 20 ng anti IFN-γ significantly abrogated the GSPL mediated protection (4342.6±173.44 parasites/1000 adherent cells). The gene discussed is IFNG; the disease is infection.