CD4
Quick Summary
CD4 is a large glycoprotein found on the surface of helper T cells, a type of white blood cell crucial for immune function. These cells are also known as CD4+ T cells because of this surface protein. CD4 acts as a receptor for HIV, the virus that causes AIDS. HIV preferentially infects and depletes cells bearing CD4, leading to a progressive weakening of the immune system. Helper T cells, with the help of CD4, play a central role in activating other immune cells, such as B cells that produce antibodies and cytotoxic T cells that kill infected cells. The loss of helper T cells due to HIV infection is a hallmark of AIDS.123
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AIDSLife cycle of HIV…their surfaces a protein called CD4. Helper T cells play a central role in normal immune responses by producing factors that activate virtually all the other immune system cells. Those include B lymphocytes, which produce antibodies needed to fight infection; cytotoxic T lymphocytes, which kill cells infected with a virus;…
Read More…their surfaces a protein called CD4. Helper T cells play a central role in normal immune responses by producing factors that activate virtually all the other immune system cells. Those include B lymphocytes, which produce antibodies needed to fight infection; cytotoxic T lymphocytes, which kill cells infected with a virus;…
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immune systemFunction of the T-cell receptor…cells display a coreceptor called CD4, which binds to class II MHC molecules, and cytotoxic T cells have on their surfaces the coreceptor CD8, which recognizes class I MHC molecules. These accessory receptors add strength to the bond between the T cell and the target cell.
Read More…cells display a coreceptor called CD4, which binds to class II MHC molecules, and cytotoxic T cells have on their surfaces the coreceptor CD8, which recognizes class I MHC molecules. These accessory receptors add strength to the bond between the T cell and the target cell.
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