Skin-Derived Precursor Cells as an In Vitro Modelling Tool for the Study of Type 1 Neurofibromatosis

Figure 1

Cellular organization of a normal nerve shaft and a neurofibroma. (a) Nerve shafts are made up of axons and associated Schwann cells. Endoneurium is connective tissue composed by collagen, fibroblasts, mast cells, capillaries and extracellular matrix. Collagen fibers are tighter and more compact near the perineurium. The perineurium is composed by flattened fibroblasts, collagen and elastic fibres. (b) In a neurofibroma, the cells are the same as in a normal nerve shaft, but increased in number. There are more Schwann cells and they can be dissociated from axons. Two kinds of Schwann cells can be detected: NF1^+/− and NF1^−/−. Fibroblasts and mast cells are also increased in number but they are all heterozygous (NF1^+/−). The collagen deposits are also increased and perineurium is usually disrupted.