CD4

noun, often attributive
\ ˌsē-(ˌ)dē-ˈfȯr How to pronounce CD4 (audio) \

Definition of CD4

: a large glycoprotein that is found associated with a T cell receptor especially on the surface of helper T cells and that binds to a major histocompatibility complex molecule on the surface of an antigen-presenting cell to facilitate antigen recognition and T cell activation often used before another nounthe CD4 geneCD4 T cells [=T cells bearing CD4 on their surface]

Note: CD4 is a receptor for HIV, and cells of the immune system bearing CD4 on their surface are preferentially infected with the virus and become progressively depleted.

— compare CD8

First Known Use of CD4

1984, in the meaning defined above

History and Etymology for CD4

cluster of differentiation

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Dictionary Entries near CD4

cd

Cd

CD

CD4

CD8

CDC

CDD

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Cite this Entry

“CD4.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/CD4. Accessed 22 Oct. 2020.

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More Definitions for CD4

CD4

noun
\ -ˈfōr, -ˈfȯr How to pronounce CD4 (audio) \

Medical Definition of CD4

: a large glycoprotein that is found associated with a T cell receptor especially on the surface of helper T cells and that binds to a major histocompatibility complex molecule on the surface of an antigen-presenting cell to facilitate antigen recognition and T cell activation often used before another nounthe CD4 geneCD4 T cells [=T cells bearing CD4 on their surface]

Note: CD4 is a receptor for HIV and cells of the immune system bearing CD4 on their surface are preferentially infected with the virus and become progressively depleted.

— compare cd8

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