Endothelial Cells in Blood Smear
A slide was submitted to the laboratory for checking the presence of cells morphologically similar to hairy cells. Microscopy revealed that the observed elements were endothelial cells.
Endothelial cells line the inner surface of the heart chambers, blood vessels (arteries, veins, and capillaries), and lymphatic vessels, forming the endothelium.
In adults, the endothelium can reach a mass of one kilogram and an area of seven square meters. It consists of a single layer of flattened cells and belongs to the simple squamous epithelium.
The endothelium functions as a semi-permeable membrane, regulating molecule transport.
The main function of endothelial cells is to regulate blood flow and arterial pressure through the secretion of vasodilators, such as nitric oxide.
During blood collection for a complete blood count and smear preparation, endothelial cells can detach from the vein wall when the needle used for venipuncture is inserted or withdrawn.
🔬 Source: from the archive of Brazilian hematology specialist Marcio Melo
