Cytokines Flashcards
Memorize the various cytokines, their principal purpose, and source
Cytokines are produced in response to what?
Antigens and pathogen-associated molecular patterns (PAMPs)
What is the function of cytokines?
Chemical messengers for the innate and adaptive immune system
What are the common PAMPs?
LPS, peptidoglycan, monomersteichoic acids, unmethylated cytosine-guanine dinucleotide or CpG sequences in bacterial and viral genomes, and double-stranded viral RNA
What are the inflammatory cytokines?
IL-1, IL-6, IL-8, and TNF-α
What produces TNF-α?
activated macrophages in response to microbes, particularly LPS of Gram(-)
What is the purpose of TNF-α?
Mediator of acute inflammation by recruiting neutrophils and macrophages by stimulating endothelial cells to produce adhesion molecules and by producing chemokines which are chemotactic cytokines. It also acts on the hypothalamus to produce fever and promotes the production of acute phase proteins
What produces IL-1?
activated macrophages, endothelial cells, and some epithelial cells
What is the purpose of IL-1?
Similar function to TNF-α but also helps activate T cells
What produces IL-6?
macrophages, endothelial cells, and T cells
What is the purpose of IL-6?
acts on the liver to mediate acute phase reactions and effects B cells in their proliferation of antibody-producing cells
What produces IL-10?
activated macrophages, dendritic cells, and Th2 cells
What is the purpose of IL-10?
It is mainly an inhibitory cytokine. It inhibits production of IFN-γ by Th1 cells, inhibits cytokine production by activated macrophages, and the expression of class II MHC and co-stimulatory molecules on macrophages
What produces IL-12?
activated macrophages and dendritic cells
What is the purpose of IL-12?
it stimulates the production of IFN-γ and causes T cells to differentiate into Th1. It also enhances cytolytic functions of Tc and NK cells.
What produces Type I interferons (IFN-α and IFN-β) ?
many cells types
What is the purpose of Type I interferons (IFN-α and IFN-β) ?
They inhibit viral replication within the cells. They increase the expression of MHC I molecules that make them more receptive to killing by T cells. They also activated NK
What produces INF-γ?
primarily by Th1 cells but can also be produced by cytotoxic T cells and NK cells