Looking at a possible difference in terms of peripheral T cell response, the splenocytes from the mouse strains, challenged ex-vivo with Pb ANKA lysate, produced variable amounts of IL-10, IFN-γ and TNF-α with different kinetics between the two genotypes ultimately ending with an immunosuppression at day 5 post-infection occurring in both mouse strains. The gene discussed is IFNG; the disease is infection.