Which of the following effects can be attributed to IL-1?

Which of the following effects can be attributed to IL-1?

• A. Mediation of the innate immune response
• B. Differentiation of stem cells
• C. Halted growth of virally infected cells
• D. Stimulation of mast cells

Answer: (A)

IL-1 is a key proinflammatory cytokine that drives the innate immune response. It’s produced by activated macrophages and other cells and acts to ramp up inflammation: it triggers fever, stimulates the hepatic acute-phase response, and increases the expression of adhesion molecules on blood vessels to recruit neutrophils and other innate immune cells to the infection site. These actions are hallmark features of the nonspecific, early defense against pathogens. Differentiation of stem cells is more specifically driven by cytokines like GM-CSF, IL-3, or IL-6. Halting growth of virally infected cells is the role of interferons that establish an antiviral state, not IL-1. Stimulation of mast cells is not a primary action of IL-1; mast cell activation is more directly prompted by IgE cross-linking and other signals.

IL-1 is a key proinflammatory cytokine that drives the innate immune response. It’s produced by activated macrophages and other cells and acts to ramp up inflammation: it triggers fever, stimulates the hepatic acute-phase response, and increases the expression of adhesion molecules on blood vessels to recruit neutrophils and other innate immune cells to the infection site. These actions are hallmark features of the nonspecific, early defense against pathogens.

Differentiation of stem cells is more specifically driven by cytokines like GM-CSF, IL-3, or IL-6. Halting growth of virally infected cells is the role of interferons that establish an antiviral state, not IL-1. Stimulation of mast cells is not a primary action of IL-1; mast cell activation is more directly prompted by IgE cross-linking and other signals.