CD4

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Related to CD8 count: CD4 cells

CD4

 
designation for an antigen found on helper T cells; see under antigen.

CD4

a type I transmembrane protein found on helper/inducer T cells, monocytes, macrophages, and dendritic cells that is involved in T-cell recognition of antigens; expressed in mycosis fungoides, Sézary syndrome, and T-cell lymphomas.

CD4

(sē′dē-fôr′)
n.
A glycoprotein predominantly found on the surface of helper T cells. In humans, it is a receptor for HIV, enabling the virus to gain entry into its host.

CD4

A transmembrane glycoprotein present on T helper/inducer cells, which participates in adherence of T cells to target cells, and is involved in thymic maturation and transmission of intracellular signals during T cell activation by the class II MHC; CD4 has inducer or helper activity for T cell, B cell, and macrophage interactions, and evokes T cell proliferation in response to soluble antigens or autologous non-T cells, providing appropriate signals for B cell proliferation and differentiation into Ig-secreting cells; CD4 is also a high-affinity receptor for HIV-1's gp120, binding 42–55 of the NH2 terminal domain amino acids, and has an Ig-like fold similar to the complementarity-determining region of the kappa light chain; CD4 also binds Igs independently of the Fc receptor, and is an accessory to the T-cell receptor

CD4

A type of protein molecule in human blood that is present on the surface of 65% of human T cells. CD4 is a receptor for the HIV virus. When the HIV virus infects cells with CD4 surface proteins, it depletes the number of T cells, B cells, natural killer cells, and monocytes in the patient's blood. Most of the damage to an AIDS patient's immune system is done by the virus' destruction of CD4+ lymphocytes. CD4 is sometimes called the T4 antigen.
Mentioned in: AIDS, AIDS Tests
References in periodicals archive ?
The number of CD8+ lymphocytes (CD8 count) rises dramatically shortly after HIV infection and remains elevated.
This was achieved by using median CD8 count values for deaths and survivors as the rep CD8 count values for deaths and survivors ad the respective lower and upper limits of iteration, and the identification of an iterated value that revealed the highest and near-equivalent univariate and multivarfiate significance.
The enrollment total T-cell count (P [less than] .001), the enrollment CD4 count (P = .016), and especially the enrollment CD8 count (P [less than] .001) were found to be significantly associated with a favorable length of survival.
An elevated CD8 count at enrollment, in contrast was found to be aq significant independent contributor to a favorable survival prognosis, thus associated with a lower risk of death.
A study of patients at earlier stages of HIV infection than those in our study found no relation between initial CD8 counts and progression to AIDS.[20] Still another study of initial CD8 counts and progression to AIDS found a weak increase in the risk of progression to AIDS associated with higher CD8 counts.[21] However, this second study was not confined to patients with initial CD4 counts [less than] 50 cells/[mm.sup.3], and it analyzed progession to AIDS over a 60-month period following the initial CD8 count.
The study identified a clinically useful CD8 count warning level of 415 cells/[mm.sup.3]; below that level the risk of death within 1 year is greater than 50%.
The median enrollmend CD8 counts for deaths and survivors of the 1-year postenrollment period were 275 and 484 cells/[mm.sup.3], respectively.
In particular, lower CD8 counts at enrollment were associated with higher risk of death within 1 year among patients with CD4 counts below 50 cells/[mm.sup.3].
The only case-control study, from the French Hospital Database on HIV, identified ties between both CD4 and CD8 counts and MI risk.
A pilot study on observations on CD4 and CD8 counts in healthy HIV seronegative individuals.
The changes in mean CD3, CD4 and CD8 counts in both the groups after treatment were not significant, after supplementation.