Tumor Necrosis Factor-α

Definition

Tumor necrosis factor-α (TNF-α) is a pro-inflammatory cytokine produced primarily by activated macrophages and other immune cells. It plays a central role in the inflammatory response and the regulation of immune cells, making it a key mediator of both inflammation and fever.

5 Must Know Facts For Your Next Test

1. TNF-α is a key mediator of the inflammatory response, triggering the release of other pro-inflammatory cytokines and promoting the recruitment and activation of immune cells.
2. Elevated levels of TNF-α are associated with various inflammatory and autoimmune diseases, such as rheumatoid arthritis, Crohn's disease, and psoriasis.
3. TNF-α plays a crucial role in the induction of fever by stimulating the production of prostaglandins in the hypothalamus, which reset the body's temperature setpoint.
4. In addition to its pro-inflammatory effects, TNF-α can also induce apoptosis (programmed cell death) in certain cell types, including tumor cells.
5. Therapeutic agents that target TNF-α, such as monoclonal antibodies, are used to treat various inflammatory and autoimmune conditions.

Review Questions

• Explain the role of tumor necrosis factor-α in the inflammatory response.
  • Tumor necrosis factor-α (TNF-α) is a key pro-inflammatory cytokine that plays a central role in the inflammatory response. Upon activation, TNF-α triggers the release of other inflammatory mediators, such as interleukins and chemokines, which promote the recruitment and activation of immune cells to the site of inflammation. TNF-α also enhances the expression of adhesion molecules on endothelial cells, facilitating the migration of immune cells into the affected tissue. Additionally, TNF-α can induce the production of prostaglandins, which contribute to the classic signs of inflammation, including redness, swelling, heat, and pain.
• Describe how tumor necrosis factor-α is involved in the regulation of fever.
  • Tumor necrosis factor-α (TNF-α) plays a crucial role in the induction of fever during the inflammatory response. When the body detects an infection or injury, TNF-α is released by activated immune cells, such as macrophages. This cytokine then acts on the hypothalamus, the part of the brain responsible for regulating body temperature. TNF-α stimulates the production of prostaglandins, which reset the body's temperature setpoint to a higher level, resulting in fever. The increased body temperature helps to create an unfavorable environment for pathogens and enhances the activity of the immune system, thereby aiding in the body's defense against infection or injury.
• Evaluate the potential therapeutic applications of targeting tumor necrosis factor-α in the treatment of inflammatory and autoimmune diseases.
  • Targeting tumor necrosis factor-α (TNF-α) has emerged as a promising therapeutic approach for the management of various inflammatory and autoimmune conditions. Due to the central role of TNF-α in the inflammatory cascade, blocking its activity can effectively reduce the severity of symptoms and disease progression in conditions such as rheumatoid arthritis, Crohn's disease, and psoriasis. Monoclonal antibodies and other biologics that inhibit TNF-α have demonstrated significant clinical benefits, helping to alleviate inflammation, reduce tissue damage, and improve the quality of life for patients. The success of these targeted therapies highlights the importance of understanding the complex mechanisms underlying inflammatory processes and the potential for developing more effective, personalized treatments by modulating key mediators like TNF-α.

Related terms

Cytokine: Small signaling proteins secreted by various cells, especially immune cells, that regulate immune responses and inflammatory processes.

Macrophage: A type of immune cell that engulfs and digests cellular debris, pathogens, and other harmful or foreign materials in the body.

Inflammation: The body's immune response to injury, infection, or irritation, characterized by redness, swelling, heat, and pain.