Transmission electron microscopy at age 4 weeks (A,B,E) and 5 months (C,D) in transgenic pigs.

<p><b>A</b>) In 4-week-old transgenic pigs, mesangial widening is associated with fiber deposition in the mesangial matrices. Magnification: 2,000×. <b>B</b>) Fibers accumulated at mesangial areas, forming early lesion. Magnification: 500×. <b>C</b>) At 5 months, established glomerular nodules showed that mesangial areas and capillary lumens are filled with bright fibers (arrows). Vacuolations of proximal tubules were also seen (arrowheads). Magnification: 300×. <b>D</b>) Subendothelial widening with loss of endothelial fenestration and mesangial interposition are shown. Note that collagen is also found in the subendothelial spaces (arrows). Magnification: 1,500×. <b>E</b>) The nodules consist of fibril collagens with cross striation, indicating interstitial-type forms of collagen fibrils. Magnification: 10,000×. <b>F</b>) Thickness of glomerular basement membranes in transgenic pigs was no different from those in wild-type pigs at 4 weeks and 5 months old. Transgenic pigs; n = 1, wild-type pigs; n = 3. Tg = transgenic pigs; WT = wild-type pigs; GBM = glomerular basement membrane.