Table of Contents
Definition / general | Terminology | Pathophysiology | Clinical features | Uses by pathologists | Microscopic (histologic) images | Positive staining - normal | Positive staining - disease | Negative stainingCite this page: Pernick N. CD23. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cdmarkerscd23.html. Accessed January 20th, 2021.
Definition / general
- Key molecule for B cell activation and growth
- References: OMIM #151445
Terminology
- Also known as low affinity IgE receptor, Fc fragment of IgE receptor and FCER
Pathophysiology
- A type C lectin that can be secreted
- After physiologic germinal cell development, the follicular dendritic cell meshwork expands and follicular dendritic cells in the light zone of the germinal center become CD23 positive
- CD23 acts as a B cell growth and activation factor, promoting differentiation into plasma cells
- Shows variability in flow cytometry expression between specimens from same patient (Am J Clin Pathol 2002;117:615)
- CD21, CD23 and CD35 are dendritic cell markers
- Interactions with IgE:
- Membranous form regulates IgE synthesis through CD21 and IgE binding (J Exp Med 2005;202:751, Acta Crystallogr F Struct Biol Commun 2014;70:305)
- Soluble form also controls IgE synthesis and homeostasis in B cells (J Immunol 2012;188:3199)
- Membranous form mediates IgE related immune responses (Clin Rev Allergy Immunol 2005;29:61)
- IgE binding site of CD23 has extensive conformational plasticity (Mol Immunol 2013;56:693)
Clinical features
- High expression on B cells in peripheral blood is associated with bullous pemphigoid (J Dermatol Sci 2004;35:53)
- CD23 antibodies may decrease adherence of Plasmodium falciparum-infected erythrocytes (Cell Microbiol 2004;6:839)
- CD23 mediates antimycobacterial activity of human macrophages (Infect Immun 2009;77:5537)
- Polymorphisms are associated with atopy, increased risk of exacerbations in patients with asthma, and high serum IgE levels (Am J Respir Cell Mol Biol 2014;50:263)
- Mantle cell lymphoma:
- Usually CD23 negative
- May have CD23 present with dim intensity by flow cytometry (Am J Clin Pathol 2003;120:760, Am J Clin Pathol 2001;116:893); however, these cases have high cyclin D1 levels (Am J Clin Pathol 2002;117:237)
- CD23+ cases may have better prognosis (Am J Clin Pathol 2008;130:166)
- Rarely has CD23+ cells in peripheral blood (Am J Clin Pathol 2002;118:758)
- Chronic lymphocytic leukemia / CLL
- High soluble CD23 is associated with aggressive disease and poorer prognosis (Leuk Lymphoma 2002;43:549, Clin Lab Haematol 2006;28:30, Cytometry B Clin Cytom 2014;86:91)
Uses by pathologists
- CD21, CD23 and CD35 are dendritic cell markers
- Differentiate SLL/CLL (CD23+) vs. mantle cell lymphoma or MALT lymphoma (CD23-)
- B cell marker, particularly for SLL/CLL, mediastinal large B cell lymphoma (Mod Pathol 2012;25:1637) and lymphoplasmacytic lymphoma
- Distinguish nodal marginal zone lymphoma from follicular lymphoma by identifying a disrupted follicular dendritic cell pattern (Int J Surg Pathol 2005;13:73)
Microscopic (histologic) images
Positive staining - normal
- Activated mature B cells expressing IgM or IgD (particularly mantle cells), activated monocytes / macrophages, T cell subsets, platelets, eosinophils, Langerhans cells, follicular dendritic cells and intestinal epithelium (encodes IgE receptor, Gastroenterology 2005;129:928)
Positive staining - disease
- B-cell CLL/SLL (almost all cases; high levels, Leuk Res 2002;26:809, Hum Pathol 1999;30:648)
- Atypical cases of CLL/SLL may have higher levels (Am J Clin Pathol 2001;116:655)
- Follicular dendritic cell tumors (including inflammatory pseudotumor type, Am J Surg Pathol 2001;25:721)
- Mediastinal large B cell lymphoma (70%, Histopathology 2004;45:619)
- Lymphoplasmacytic lymphoma (61%, usually dim intensity by flow cytometry, Am J Clin Pathol 2005;124:414, Clin Lymphoma 2005;5:246)
- Hairy cell leukemia (17%, Am J Clin Pathol 2006;125:251)
- Diffuse large B cell lymphoma (16%)
Negative staining
- Basophils, resting B cells
- Other B cell lymphomas including Burkitt lymphoma, Burkitt-like lymphoma (Am J Surg Pathol 2005;29:1652), follicular lymphoma, mantle cell lymphoma and marginal zone lymphoma (Am J Surg Pathol 1999;23:59, Mod Pathol 1998;11:967)
- Most T cell lymphomas, inflammatory fibroid polyps of the gastrointestinal tract (although of dendritic cell origin, Am J Surg Pathol 2004;28:107), follicular dendritic cell tumor and interdigitating dendritic cell tumor