TNF and infection: Inflammation, a defense reaction to alert the immune system and protect the host from infection with various pathogens such as bacteria, viruses, and fungi, is generally beneficial to the host due to its ability to repair injured tissues and maintain homeostasis, which are regulated by numerous inflammatory mediators and cytokines including nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor (TNF-α) [1].