Figure 4

NG2-DsRed⁺pericyte accumulation, but no collagen production, in a mouse model of kidney fibrosis. (A) Immunohistochemistry of unobstructed kidney sections in a Nestin-GFP/NG2-DsRed mouse showing blood vessels labeled with the endothelial cell marker CD31; Nestin-GFP^–-/NG2-DsRed⁺ (type-1) and Nestin-GFP⁺/NG2-DsRed⁺ (type-2) pericytes are attached to it. All panels show the same area for different channels (CD31, NG2-DsRed, Nestin-GFP, Hoechst, and merged images). Region in yellow box shows type-1 and type-2 pericytes close to CD31⁺ blood vessels, magnified in (C). (B) Representative immunofluorescence staining of type I collagen (Col I) in the kidney 14 days after UUO in a Nestin-GFP/NG2-DsRed mouse. All panels show the same area for different channels (Col I, NG2-DsRed, Nestin-GFP, Hoechst, and merged images). Region in yellow box shows an area with high type-1 pericyte concentration, magnified in (D). (C) Type-1 and type-2 pericytes close to CD31⁺ blood vessels, magnified from (A). (D) High type-1 pericyte concentration, magnified from (B). Note that in this model of kidney fibrosis, NG2-DsRed⁺ cells do not express Col I. (E) Quantification of type-1 and type-2 pericytes before and 14 days after UUO (n = 3 mice; 10 kidney sections from each). (F) Percent of cells expressing Col I in the kidney 2 weeks after UUO. Note that NG2⁺ pericytes do not contribute to collagen type I production. Scale bars = 100 μm.