chapter 3 immunology - Cytokines, Chemokines & Their Properties

What are cytokines?

Proteins that mediate immune functions by binding cell-surface receptors.

What does cytokine signaling commonly change?

The target cell's transcriptional program.

What is autocrine signaling?

A cytokine acts on the cell that secreted it.

What is paracrine signaling?

A cytokine acts on nearby cells.

What is endocrine signaling?

A cytokine travels through blood to act on distant cells.

Which cytokine signaling modes are most common?

Autocrine and paracrine.

What are chemokines?

Cytokines that direct leukocyte migration.

What is the main function of chemokines?

Direct leukocyte migration.

What is pleiotropy?

One cytokine causes different effects in different target cells.

What is redundancy?

Different cytokines cause similar effects.

What is synergy?

Two cytokines together produce a greater-than-additive effect.

What is antagonism?

One cytokine inhibits another cytokine's effect.

What is a cytokine cascade?

One cytokine causes production of additional cytokines.

One cytokine with different effects = ?

Pleiotropy.

Different cytokines with the same effect = ?

Redundancy.

Two cytokines producing an enhanced effect = ?

Synergy.

One cytokine blocking another = ?

Antagonism.

One cytokine causing production of more cytokines = ?

Cascade.

What type of receptors are chemokine receptors?

G-protein-coupled receptors (GPCRs).

How many times do chemokine receptors cross the membrane?

Seven.

Why is localized cytokine secretion useful?

It concentrates the signal near the intended target cell.