Cytokines and Immune Response Quiz

Which cytokine is critical for T-cell growth and proliferation?

• IL-6

• IL-10

• IL-2

• IFN-γ

Answer explanation

IL-2 is a cytokine produced by activated T-helper cells that promotes T-cell growth, proliferation, and differentiation. It plays a central role in the adaptive immune response by amplifying T-cell activation.

What is the primary function of IL-6 in the immune response?

• Suppresses macrophage activity

• Stimulates acute-phase protein production

• Promotes B-cell apoptosis

• Recruits neutrophils to infection sites

Answer explanation

IL-6 is a pro-inflammatory cytokine that triggers the liver to produce acute-phase proteins (e.g., CRP). It also supports the immune response during infection or injury.

IL-10 is an anti-inflammatory cytokine.

• True

• False

Answer explanation

IL-10 suppresses inflammatory responses by inhibiting cytokine production from macrophages and dendritic cells. It helps regulate immune responses to prevent excessive inflammation.

Which cytokine is responsible for recruiting neutrophils to infection sites?

• IL-1

• IL-17

• IL-8

• IL-4

Answer explanation

IL-8 is a chemokine that acts as a chemoattractant, guiding neutrophils to the site of infection or tissue damage for phagocytosis and pathogen elimination.

Which cytokine is most associated with chronic inflammation?

• IL-4

• IL-17

• TNF-α

• IL-6

Answer explanation

IL-17 is produced by Th17 cells and is heavily involved in chronic inflammation by recruiting neutrophils and enhancing pro-inflammatory cytokine production.

What is pleiotropy in cytokine action?

• A cytokine with no effect

• A cytokine with multiple effects on different cells

• Cytokines neutralizing each other

• A cytokine exclusive to innate immunity

Answer explanation

Pleiotropy refers to a single cytokine influencing various cell types and processes. For example, IL-4 affects B cells (antibody production) and T cells (Th2 differentiation).

Cytokines are only produced by T cells.

• True

• False

Answer explanation

Cytokines are produced by various cells, including T cells, macrophages, dendritic cells, B cells, and others, depending on the immune response stage.

Which cytokine is key for macrophage activation in innate immunity?

• IL-12

• IFN-γ

• IL-10

• IL-6

Answer explanation

IFN-γ, secreted by Th1 cells and NK cells, activates macrophages to enhance their ability to kill pathogens and present antigens.

What is the role of IL-4 in the immune response?

• Promotes Th1 differentiation

• Enhances NK cell activity

• Suppresses macrophage activation

• Promotes Th2 differentiation

Answer explanation

IL-4 drives naive T-helper cells to differentiate into Th2 cells, which are critical for activating B cells and humoral immunity.

IL-1 is responsible for initiating the acute inflammatory response and inducing fever.

• True

• False

Answer explanation

IL-1 is a pro-inflammatory cytokine that triggers fever by acting on the hypothalamus and promotes the expression of adhesion molecules for immune cell migration.