Fig. 3

Spinal cord TDP-43 pathology in ChAT-tTA/TRE-TDP-43^M337V rats was detected by immunohistochemistry with anti-TDP-43 antibodies regardless of hippocampal injected tau construct. a Frequency of pathology-bearing motor neurons normalized against total number of motor neurons. The presence of spinal TDP-43 pathology approaches significance in the rats expressing tau^T175D when compared to GFP expressing rats (p < 0.1). MN = motor neuron, GFP = GFP only control, tau^WT = GFP-tagged tau^WT protein construct, tau^T175D = GFP-tagged tau^T175D protein construct). This was not significant by one-way ANOVA (p = 0.052). b Photomicrograph showing spinal cord dorsal horn TDP-43 cytosolic inclusion in a motor neuron. c Photomicrograph of a spinal motor neuron showing depleted nuclear TDP-43 with cytosolic TDP-43 and surrounding glial cells. d Photomicrograph of spinal motor neurons exhibiting punctate TDP-43 pathology. e Confocal imaging detecting cleaved caspase-3 (green) in a motor neuron co-expressing human TDP-43 (red) punctate pathology. This was observed in all ChAT-tTA/TRE-TDP-43^M337V rats where TDP-43^M337V displayed pathology regardless of hippocampal tau expression (n = 3 for all groups). Scale bar = 20 μm