Which of the following Interleukin is raised in a fever?

i.e., TNF-α “IL-1 and TNF-α are the two most important pyrogens” — Physiology basics. Pyrogens Pyrogens are substances that cause fever. Pyrogens may be exogenous or endogenous a) Exogenous → Bacterial toxins b) Endogenous → IL-1, TNF-a, IL-6, Interferons, Ciliary neurotrophic factor These pyrogens increase the level of PGE2 in the hypothalamus that elevates the thermoregulatory set point and causes fever.