CD16

Optimal result: 3 – 22 %

CD16-positive T cells have been found in patients with chronic viral infections or after organ transplantation as well as in patients with severe COVID-19. CD16 expression enables antibody-mediated degranulation and thus allows T cell receptor-independent cytotoxicity.

CD16, also known as FcγRIII, refers to a cluster of differentiation molecule found on the surface of various immune cells, including natural killer cells, neutrophils, monocytes, macrophages, and certain T cells. CD16 has been identified as two different receptors: FcγRIIIa (CD16a) and FcγRIIIb (CD16b). These receptors participate in signal transduction and are involved in antibody-dependent cellular cytotoxicity (ADCC), which is a process where immune cells target and destroy cells coated with specific antibodies.

CD16, also known as FcγRIII, refers to a cluster of differentiation molecule found on the surface of various immune cells, including natural killer cells, neutrophils, monocytes, macrophages, and certain T cells. CD16 has been identified as two different receptors: FcγRIIIa (CD16a) and FcγRIIIb (CD16b). These receptors participate in signal transduction and are involved in antibody-dependent cellular cytotoxicity (ADCC), which is a process where immune cells target and destroy cells coated with specific antibodies.

The FcγRIIIa receptor (CD16a) is expressed on mast cells, macrophages, and natural killer cells as a transmembrane receptor. On the other hand, the FcγRIIIb receptor (CD16b) is only expressed on neutrophils. FcγRIIIb is the only Fc receptor anchored to the cell membrane by a glycosyl-phosphatidylinositol (GPI) linker and plays a significant role in triggering calcium mobilization and neutrophil degranulation. Together, FcγRIIIa and FcγRIIIb can activate degranulation, phagocytosis, and oxidative burst, allowing neutrophils to eliminate opsonized pathogens.

CD16 binds to the Fc portion of IgG antibodies, which activates antibody-dependent cell-mediated cytotoxicity (ADCC) in human NK cells. CD16 is required for ADCC processes carried out by human monocytes.

References:

https://www.sciencedirect.com/topics/neuroscience/cd16

CD16
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