Fig. 8.

Diffuse cutaneous systemic sclerosis (dcSSc) skin, transmission electron microscopy. (A) Early dcSSc. A telocyte with a small perinuclear cytoplasm and slender telopodes is embedded in a matrix composed of closely packed collagen bundles. Swollen mitochondria and vacuoles (arrows) are present in the cytoplasm. (B) Advanced dcSSc. Telocytes and telopodes embedded in the fibrotic extracellular matrix show features of degenerating cells. The cytoplasm is dark and contains swollen mitochondria (arrows), vacuoles and lipofuscinic bodies. Many cell debris are evident. (C) Early dcSSc. A telocyte displaying a normal morphology embraces with telopodes a large and abnormal elastin fibre. (D) Early dcSSc. Normal telocytes surround the thickened basal lamina (asterisk) of a blood vessel displaying a patent lumen. (E) Early dcSSc. Telocytes with a normal morphology are evident around nerve bundles. Abundant collagen fibres separate telopodes from the nerve bundle. A fibroblast is in the close vicinity of a telocyte and is surrounded by telopodes. (F) Advanced dcSSc. Telocytes are not identifiable around an occluded microvessel. Only a few cell debris are observed. The vessel basal lamina is markedly thickened (asterisk). TC: telocyte; Tp: telopode; Coll: collagen; Ela: elastin; E: endothelial cell; P: pericyte; N: nerve; F: fibroblast. Scale bars are indicated in each panel.