CD Markers

Reviewer: Nat Pernick, M.D. (see Authors page)

Revised: 29 December 2015, last major update February 2002

Copyright: (c) 2002-2015,, Inc.

PubMed Search: CD81[title]
Cite this page: CD81. website. Accessed October 20th, 2018.
Definition / general
  • Also called Target of an Anti-Proliferative Antibody (TAPA1)
  • Receptor for Hepatitis C Virus E2 protein in B cells (J Virol 2006;80:8695)
  • Also required for Plasmodium falciparum infectivity (Nat Med 2003;9:93)
  • Upregulation on HIV1+ B cells may ultimately cause lymphoproliferative disorders (Clin Exp Immunol 2007;147:53)
  • On B cells, is complexed with CD21, CD19 and Leu13; facilitates complement recognition
  • Member of tetraspanin family; has close associations with major histocompatibility complex class I/II proteins
  • Appears to promote muscle cell fusion and support myotube maintenance
  • References: OMIM #186845
Uses by pathologists
  • No significant clinical use by pathologists
Positive staining - normal
  • Lymphocytes, endothelial cells and epithelial cells
Positive staining - tumors
Negative staining
  • Erythrocytes, platelets and neutrophils