Hematology Lessons Best Lab: Buffy Coat/Layer (Peripheral Blood Mononuclear Cell

Peripheral Blood Mononuclear Cell (PBMC)

A peripheral blood mononucleated cell (PBMC) is any WBC having a single round nucleus. Typically lymphocytes, monocytes and macrophages are grouped under this classification. These WBCs are a critical component in the immune system to tackle against infection and adapt to pathogenic intruders. The lymphocyte population consists of T cells (CD4 and CD8 positive ~75%), B cells and NK cells (~25% combined).

These cells can be extracted from whole blood using ficoll, a hydrophilic polysaccharide that separates layers of blood, which will separate the blood into a top layer of plasma, followed by a layer of PBMCs and a bottom fraction of polymorphonuclear cells (such as neutrophils, basophils and eosinophils) and erythrocytes. The polymorphonuclear cells can be further isolated by lysing the red blood cells. 

Buffy Layer/Coat