CD Markers
CD16/CD16a
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: CD16a[title]
Related topics: CD16b
CD16/CD16a
Author: Nat Pernick, M.D.
Topic Completed: 1 December 2013
Minor changes: 2 October 2020
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: CD16a[title]
Related topics: CD16b
Table of Contents
Definition / general | Pathophysiology | Uses by pathologists | Positive staining - normal | Positive staining - disease | Negative stainingCite this page: Pernick N. CD16/CD16a. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cdmarkerscd16.html. Accessed January 15th, 2021.
Definition / general
- CD16 has been identified as IgG, Fc receptors FcγRIIIa (CD16a) and FcγRIIIb (CD16b), which participate in signal transduction
- Also known as Fc gamma receptor III A, FCGR3A, low affinity immunoglobulin gamma Fc region receptor III-A
- CD14+ CD16+ monocytes have increased capacity to produce proinflammatory cytokines such as TNF-alpha, and are elevated in various inflammatory diseases, including coronary artery disease (Thromb Haemost 2004;92:419)
- CD16a polymorphisms influence: (a) the severity but not the incidence of IgA nephropathy in Japanese patients (Nephrol Dial Transplant 2005;20:2439); (b) pathogenesis of coronary artery disease (Atherosclerosis 2005;180:277); (c) clinical response to rituximab (DNA Cell Biol 2012;31:1671, Br J Haematol 2011;154:223), and infliximab for Crohn disease (Immunogenetics 2013;65:265)
- Can detect with real time PCR (Cancer Genet 2013;206:130)
- Loss of CD16a in children is associated with recurrent viral infections
- References: OMIM #146740
Pathophysiology
- Gene is similar to that for CD16b
- Binds various IgG molecules, including rheumatoid factor
- Mediates antibody dependent cytotoxicity of foreign cells, phagocytosis and other antibody-dependent responses, but if target cell has class I MHC, the NK cell's killer cell inhibitory receptor (KIR) inhibits cytolysis
- Mediates platelet satellitism (Am J Clin Pathol 1995;103:740)
- Affinity to ligand is regulated by glycosylation (Immunology 2003;110:335)
Uses by pathologists
- NK cell and macrophage marker
- Used to subtype leukemia / lymphomas
- Note: preincubation with CD16 / CD32 antibodies is commonly used to prevent nonspecific binding
Positive staining - normal
- NK cells, granulocytes, monocytes / macrophages, T cells (reactive), immature thymocytes and placental trophoblast
Positive staining - disease
- NK proliferative disorders, hepatosplenic alpha-beta and gamma-delta T cell lymphomas (variable), T cell large granular lymphocyte leukemia (variable)
- CD16 expression, normally absent from eosinophils, is upregulated with allergic conditions (J Allergy Clin Immunol 2002;109:46) or when stimulated in vitro with platelet activating factor or IFNgamma (Int Arch Allergy Immunol 2004;134:165)
Negative staining
- Basophils; NK / T cell lymphoma nasal type
