Extraglomerular mesangial cells

Extraglomerular mesangial cells (or lacis cells) are light-staining cells in the kidney found outside the glomerulus, near the vascular pole and macula densa.

Lacis cells form the juxtaglomerular apparatus in combination with two other types of cells: the macula densa of the distal convoluted tubule and Juxtaglomerular cells of the afferent arteriole. This apparatus controls blood pressure through the Renin-Angiotensin-Aldosterone system. The specific function of Lacis cells is not well understood, although it has been associated with the secretion of erythropoietin.