Platelet-Derived Growth Factor Promotes Glomerular Mesangial Cells Differentiation of Human Bone Marrow Hematopoietic Stem Cells - An In Vitro Study

Glomerular filtration function and homeostasis are largely due to the cross-talk between podocytes, endothelial cells, and mesangial cells (MCs). Any disturbance in this association causes glomerular diseases (GD). Cell-based therapies are the best option in the treatment of GD. It is contemplated that hematopoietic stem cells (HSCs) are best suited to regenerate these cells; earlier, we have shown the differentiation of HSCs into podocytes. In this study, MCs formation was initiated with retinoic acid (RA), BMP-7, and Activin A, resulting in comma-shaped intermediate mesoderm (IM) cells prominently expressing Osr1. Followed by inducing with EGF, FGF, and BMP-7, which resulted in elongated metanephric mesenchyme (MM) cells conspicuously expressing Pax2, Wt1, Foxd1, and Eya1. Finally, MM cells were induced with platelet-derived growth factor to form polygonal-shaped MCs expressing α-smooth muscle actin, desmin, CD44, and PDGFRβ. The growing MCs showed positivity to periodic acid Schiff's, and ANAE staining with a prominent expression of the Itga8 elucidating phagocytic property of MCs. These MCs showed conspicuous expression of CD133, notch-2, and telomerase, determining the quiescence nature with a 31.2% proliferation rate revealed through Ki-67 staining. The functionality of MCs was assessed by growing MCs in 5.5 and 25 mM glucose concentrations, and noticeable expression of angiotensinogen, angiotensin-I and II, angiotensin-converting enzyme, collagen-4, fibronectin, and TGFβ1 was observed in 25 mM concentration, while lowered expression of these genes was observed in 5.5 mM concentration explaining the role of MCs in regulating the filtration pressure. All these findings demonstrate that HSCs can rejuvenate the insulted glomerulus.