This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Febrile response in CNS is mediated by? 
Select and explain. 
A. Bacterial toxin, B. IL-1, C. IL-6, D. All
D: All
Answer: D: All 
Explanation: Ans. is 'a' i.e., Bacterial toxin; 'b' i.e., IL-1; 'c' i.e., IL-6 Pyrogenes Pyrogenes are substances that cause fever. Pyrogens may be exogenous or endogenous Exogenous --> Bacterial toxins Endogenous --> IL-1, TNF-a, IL-6, Interferons, Ciliory's neurotropic factor These pyrogenes increase the level of PGE2 in the hypothalamus that elevates the thermoregulatory set point and causes fever.