Fig. 1
From: Purkinje cell injury, structural plasticity and fusion in patients with Friedreich’s ataxia
Neuronal injury in FRDA. Tissue sections derived from FRDA cases showing pathological lesions. a Characteristic FRDA lesions. (i) H&E staining of the dorsal root ganglion showing shrunken neurones with severe eosinophilia of the perikaryon (black arrows), neuronal lipofuscin accumulation (black triangle) and a nest of reactive satellite cells known as a nodule of Nageotte indicating ganglion neuronal cell degeneration (red arrow). (ii) A section from the upper cord stained with Luxol fast blue and Cresyl violet showing marked dorsal column loss, more marked in the gracile (black arrow) than the cuneate fasiculi (black triangle). There is also significant degeneration of the posterior spinocerebellar tracts (red arrow). (iii) Luxol fast blue and Cresyl violet staining of the spinal cord showing loss of neurons from Clarke’s Column (black hatched area). (iv) Grumose degeneration; disorganisation and proliferation of the Calbindin-D28K positive synaptic terminals situated around the large neurons of the cerebellar dentate nucleus. b Signs of Purkinje cell injury. (i) Cerebellar sections immuno-labelled with Calbindin-D28K and counterstained with haematoxylin (blue) showing the location of the Purkinje cell layer situated within the grey matter on the border of the molecular and granular cell layers. (ii) Bielschowsky silver staining of the cerebellar cortex showing occasional loss of Purkinje cells leading to the presence of ‘empty baskets’ (white hatched areas). H&E staining showing the Purkinje cell layer with (iii) occasional shrunken Purkinje neurones with mild eosinophilia of the perikaryon (black triangle), and (iv) Purkinje cells with loss of Nissl substance and shrunken basophilic homogenous nuclei (black arrow). c (i) A cerebellar folium showing frequent Calbindin-D28K positive hypertrophic axons situated throughout the grey matter (black arrows). (ii) Cerebellar cortex showing Calbindin-D28K positive axonal torpedoes (black arrows). The hatched area in (ii) represents the higher magnified image (iii)