Classical complement activation pathway-mediated synapse elimination in the severely compressed spinal cord. (A) Representative magnified image of the Iba-1/C1q/PSD95 triple-positive area in the compressed spinal cord. Many C1q-positive puncta were colocalized with the postsynaptic protein PSD95 (several examples are circled). Scale bar: 10 μm. (B) Electron microscopic image of the compressed spinal cord, showing extensive contact between presynaptic/postsynaptic elements and activated microglia/macrophage processes. Scale bar: 0.2 μm. (arrowhead; synapse, pre; presynapse, post; postsynapse, M; microglia/macrophage).