\ ˌsē-(ˌ)dē-ˈfȯr 
\
\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.
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More Definitions for CD4
CD4
noun\ -ˈfōr, -ˈfȯr \
\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 cd8Comments on CD4
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The first known use of CD4 was in 1984
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