25.12 : 抗菌蛋白

Antimicrobial proteins, such as interferons, the complement system, iron-binding proteins, and antimicrobial peptides, enhance the immune response by killing pathogens or obstructing their reproductive capabilities.

Interferons are released by activated lymphocytes, macrophages, and virus-infected cells and diffuse to neighboring healthy cells.

They induce the synthesis of antiviral proteins inside target cells that inhibit viral replication.

The alpha, beta, and gamma are the three main types of interferons.

On the other hand, the complement system consists of over 20 different plasma proteins.

They are usually inactive in the plasma, but when activated, they enhance inflammatory immune reactions, promoting the lysis of bacterial cells or phagocytosis of virus-infected cells.

Iron-binding proteins, like transferrin or lactoferrin, create an environment with low levels of free iron, inhibiting the growth of certain bacteria.

Lastly, antimicrobial peptides, such as defensins produced by neutrophils, are small proteins with broad-spectrum antimicrobial activity. They can kill various pathogens by damaging their cell membranes or viral envelopes.