Expression of platelet-derived endothelial cell growth factor and its potential role in up-regulation of angiogenesis in scarred kidneys secondary to urinary tract diseases.
The mechanism of neovascularization secondary to renal interstitial fibrosis is not well understood. Platelet-derived endothelial cell growth factor (PD-ECGF) is known to promote angiogenesis. We examined the expression of PD-ECGF immunohistochemically in 9 normal kidneys and 26 scarred kidneys secondary to urinary tract diseases. To estimate up-regulation of angiogenesis, microvessels were counted by immunostaining endothelial cells for CD34. Immunostaining of PD-ECGF was observed in most Bowman's capsules, occasional tubules, and some interstitial mononuclear cells in normal kidneys. A remarkable increase of immunostained PD-ECGF was found in the tubules and interstitial mononuclear infiltrates in the scarred kidneys. The predominant cell type in the infiltrate was T cells (CD3(+)). The microvessel count and mean numbers of PD-ECGF(+) tubular and interstitial mononuclear cells increased with increasing interstitial fibrosis. A significant correlation was noted between microvessel count and the number of PD-ECGF(+) tubular cells (P = 0.0002) or PD-ECGF(+) interstitial mononuclear cells (P < 0.0001). Immunostaining of endogrin, a marker of endothelial proliferation, increased in the microvessels located in the fibrotic interstitial spaces. These results suggest that angiogenesis may play a critical role in the progression of tubulointerstitial injuries and that up-regulation of PD-ECGF may contribute to neovascularization.
Konda
R
R
Department of Urology, Tohoku University School of Medicine, Sendai, Japan. r-konda@uro.med.tohoku.ac.jp
Sato
H
H
Sakai
K
K
Sato
M
M
Orikasa
S
S
Kimura
N
N
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007668:Kidney / Q000098:blood supply* / Q000378:metabolism* / Q000473:pathology; D008297:Male; D009389:Neovascularization, Pathologic; D013939:Thymidine Phosphorylase / Q000096:biosynthesis*; D015854:Up-Regulation; D014570:Urologic Diseases / Q000150:complications / Q000378:metabolism* / Q000473:pathology
D013939:Thymidine Phosphorylase