Molecular Classification
Receptor, Immunoglobulin superfamily
Other Names
CD16a, FCGR3A
Disease Roles
Autoimmune diseasesCancerInfection

Fc gamma receptor IIIa Overview

Fc gamma receptor IIIa (CD16a) is a low-affinity receptor for the Fc portion of IgG, primarily expressed on NK cells, macrophages, and some monocytes. It plays a central role in ADCC, phagocytosis, and cytokine production, making it a key target for therapeutic antibodies and implicated in autoimmune disease mechanisms. Surface expression is regulated by proteolytic shedding.

Mechanism of Action

Engagement with Fc region of IgG on antibody-coated cells, leading to NK cell activation and cytotoxicity or macrophage phagocytosis.

Biological Functions

Antibody-dependent cell-mediated cytotoxicity (ADCC)
Phagocytosis
Cytokine production
Immune response

Disease Associations

Autoimmune diseases
Cancer
Infection
Immune thrombocytopenia (ITP)

Safety Considerations

  • Potential for inflammatory reactions
  • Downregulation of surface expression after activation

Interacting Drugs

Therapeutic antibodies