PBMC

A Peripheral Blood Mononuclear Cell (PBMC) is a blood cell having a round nucleus, such as a lymphocyte or a monocyte. These blood cells are a critical component in the immune system to fight infection and adapt to intruders.These cells are often extracted from whole blood using ficoll, a hydrophilic polysaccharide that separates layers of blood, with monocytes and lymphocytes forming a buffy coat under a layer of plasma. This buffy coat contains the PBMCs.PBMCs are widely used in research and clinical uses every day.  HIV research uses them because PBMCs include CD4+ cells, the cells HIV infects.
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