Mesangial cells–which historically have received less attention than their more “sexy” neighbor cell types of the glomerulus such as podocytes & endothelial cells–are actually quite interesting. They were originally seen as having purely a “matrix” function–that is, serving as the anchor points for the glomerular capillary walls. However the evolving view of the mesangial cell is that this cell type has other important functions, including:
-contraction: mesangial cells derive from smooth muscle cells and may play a role in regulating intraglomerular hemodynamics.
-phagocytosis: playing a role in the immune system of the kidney.
-synthesis & secretion of growth factors and cytokines.
-mesangial cells are also capable of producing excess amounts of matrix, which may be important in certain diseases (e.g., diabetic nephropathy, IgA Nephropathy).
A few other related histological terms:
Mesangial sclerosis refers to an increase in the amount of mesangial matrix, either with or without a concomitant increase in mesangial cellularity. There is an autosomal dominant form of this disease which may be caused by mutations in the Wilms tumor (WT1) gene.
Mesangiolysis, in contract, refers to a dissolution of the mesangial matrix and a degeneration of mesangial cells. Mesangiolysis is seen in a wide range of condition including thrombotic microangiopathies , malignant HTN, diabetic nephropathy, and others.