Home   Chapter Home   Jobs   Conferences   Fellowships   Books


CD Markers


Reviewers: Nat Pernick, M.D. (see Reviewers page)
Revised: 22 January 2011, last major update January 2011
Copyright: (c) 2002-2011, PathologyOutlines.com, Inc.


● Antigen which helps downregulate the immune system


● Also called membrane cofactor protein (MCP), Trophoblast leukocyte common antigen


● Has multiple isoforms, but unlike CD45, they donít appear to have clinical significance
● Cofactor for proteolytic cleavage of C3b and C4b by factor I (J Immunol 2002;168:6298), which prevents inappropriate complement activation, especially via alternative pathway, by limiting formation and function of C3 convertases
● Induces regulatory T cells (Nature 2003;421:388), which suppress immune function by secreting IL-10, and may prevent autoimmunity; various pathogens (see below) appear to exploit this property by binding to CD46 to induce an immunosuppressive phenotype

Clinical features

● Receptor for adenovirus (various serotypes, J Virol 2005;79:7503), HHV-6 (Cell 1999;99:817, J Biol Chem 2003;278:25964), measles virus (Cell 1993;75:295), Neisseria gonorrhoeae (J Cell Biol 2002;156:951), Streptococcus pyogenes (Infect Immun 2008;76:3951)
● Expression is often increased on tumor cells
● Homozygosity for specific alleles is a high risk factor for some types of recurrent pregnancy loss (Hum Reprod 2006;21:818)
● Mutations predispose to familial hemolytic uremic syndrome atypical type 2 (Proc Natl Acad Sci USA 2003;100:12966)


● No significant clinical use by pathologists

Positive staining - normal

● All cells except erythrocytes and some bone marrow cells

Negative staining

● Red blood cells

Additional references

MIM 120920, Springer Semin Immunopathol 2005;27:345

End of CD Markers > CD46

This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.

All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).