Expression of IFNG, TNFA, IL1B, NOS2, IL6, IL10, NOS2, SMAD6, and SMAD7 was measured at 4 and 8 (acute) or 12 and 16 (chronic) weeks post infection, using total RNA isolated from lung homogenates of rabbits with placebo- or Fe-supplementation (Figure 6E–H). The gene discussed is SMAD6; the disease is infection.