Table of Contents
Definition / generalCite this page: Pernick N. Tumor necrosis factor. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stainstnf.html. Accessed January 18th, 2021.
Definition / general
- Also called cachectin
- Initiates similar responses as lymphotoxin alpha
- Secreted by macrophages and lipopolysaccharides or macrophage activating agents
- Binds to 55kDa receptor on many cells throughout body
- Mediators: TRADD, TRAP-1, 55.11
- Has many biologic activities; initiate signals for cell proliferation and apoptosis; required for normal development and function of immune system; suppresses expression of lipoprotein lipase and anabolic enzymes in fat
- In large boluses, modifies coagulation properties of endothelial cells, activates neutrophils, induces release of inflammatory cytokines (IL-1), causing cardiovascular collapse
- In small amounts, causes symptoms of inflammatory response of bone resorption, fever, anemia, wasting
- Both triggers apoptosis and activates NFKB which blocks apoptosis
- TNF and IL-1 react with hypothalamic receptors, leading to stimulation of prostaglandin and leukotriene mediated pathways that reset brains thermoregulatory center