Recent data from our team and others drew new attention on a discrete population of mesenchymal cells that wraps around vessels, variously called mural cells
, perivascular cells or pericytes, as a major source for profibrotic stromal cells generating scar tissue.
As in normal blood vessels, tumor vessels consist of endothelial cells, mural cells (pericytes and smooth muscle cells), and basement membrane (Baluk et al.
Tumor vessels are leaky, immature, or morphologically abnormal because of the absent or incomplete basement membrane and mural cells (pericytes and smooth muscle cells).
Arrow indicates mural cells (magnification: 320x; bar = 50 [micro]M).
One typical marker of mural cells is platelet derived growth factor receptor Beta (PDGFR-Beta).
Because the FDCs could not possibly have developed from the host animals, this experiment positively demonstrates that mural cells can give rise to FDCs.
The recognition that FDCs derive from pluripotent mural cells helps understanding autoimmune and pathogen-driven chronic inflammatory conditions, the generation of FDC-derived tumors, and certain aspects of the pathogenesis of acquired immunodeficiency syndrome (AIDS) and of prion infections.