As well, proinflammatory agents such as interleukin-6 (IL-6), C-reactive protein, and tumor necrosis factor-alpha (TNF-α) can enhance resistance to infectious disease but also susceptibility in old age to a chronic low-grade inflammation, or “inflammaging,” that constitutes a highly significant factor for both morbidity and mortality [5, 6]. The gene discussed is TNF; the disease is infectious disease.