Stains & CD markers

Last author update: 1 May 2013
Last staff update: 23 October 2023

Copyright: 2002-2024,, Inc.

PubMed Search: CD31 [title]

Lauren N. Stuart, M.D., M.B.A.
Page views in 2023: 17,290
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Cite this page: Stuart L. CD31. website. Accessed June 16th, 2024.
Definition / general
  • Cell adhesion molecule required for leukocyte transendothelial migration under most inflammatory conditions
  • Most sensitive and specific endothelial marker in paraffin sections
  • Also known as platelet endothelial cell adhesion molecule (PECAM1, OMIM 173445), PECA1, GPIIA, endoCAM, CD31 / EndoCAM (Entrez Gene: platelet / endothelial cell adhesion molecule)
  • Member of immunoglobulin superfamily
  • Ligands are CD38 and vitronectin receptor (αvβ3 integrin, CD51 / CD61) (Cancer 2003;97:1914, J Cell Biol 1995;130:451)
  • Cell adhesion molecule that is found on the surface of platelets, monocytes, neutrophils and some types of T cells
  • Major constituent of endothelial intercellular junction
  • Plays a key role in leukocyte trafficking across endothelium / transendothelial migration (Blood 2003;101:2816) and integrin activation
  • Also important for angiogenesis and removal of aged neutrophils from body
  • May mediate signal-transduction pathway regulating capacitation in spermatozoa (J Cell Sci 2005;118:4865)
  • May act as a minor histocompatibility antigen in HLA identical stem cell transplantation (Bone Marrow Transplant 2005;36:151)
Clinical features
  • CD31+ T cells (angiogenic T cells) have vasculoprotective and neovasculogenic qualities; undergo numerical and functional impairments with advancing age (J Appl Physiol 2010;109:1756)
  • CD31+ Annexin V+ circulating microparticles are risk factor for cardiovascular disease (Eur Heart J 2011;32:2034)
  • Membranous (not cytoplasmic) immunostain; endothelium is a positive internal control
  • Potential pitfall: don't confuse CD31+ macrophages (granular, membranous expression) with a vascular tumor (Am J Surg Pathol 2001;25:1167)
Uses by pathologists
Microscopic (histologic) images

Cases #107, 187, 77
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Retiform hemangioendothelioma

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Kidney, glomus tumor

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Normal structure:
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Glomeruli (fig A)

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Alveoli (fig A)

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Spleen (fig A)

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Liver (fig A)

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Lymph nodes (fig A)

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Skin (fig A)

Benign vascular tumors / processes:
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Skin - diffuse dermal angiomatosis

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Skin - epithelioid hemangioma

Malignant vascular tumors:
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Kaposi sarcoma

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Lymphovascular invasion:
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Colorectal carcinoma

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Uterus, endometrial carcinoma
stage I

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Uterine leiomyosarcoma

Positive staining - normal
Positive staining - disease
Negative staining
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