Polyethylene Glycol-Chitosan Fusogen Enables Walking Recovery in Pigs After Complete Spinal Cord Transection

Researchers at the Sklifosovsky Institute transected the spinal cords of five anaesthetized pigs under cooling, then stabilized the stumps and administered a polyethylene glycol-chitosan fusogen to three animals via direct injection and repeated intravenous doses. All received daily electrostimulation and anti-inflammatory drugs. Treated pigs showed sensory responses by day two, standing attempts by day seven, and functional walking with axonal bridges across the gap by study end, accompanied by reduced degeneration on histology. The fusogen is hypothesized to reseal axonal membranes and promote limited end-to-end fusion, preserving some conduction in a manner distinct from guided regeneration strategies. Context from prior rodent fusogen work and Canavero-linked head-transplant claims highlights persistent concerns over axon sparing versus true reconnection, as random regrowth rarely restores targeted motor circuits. Larger blinded replications with electrophysiological verification of conduction across the lesion and quantitative axon tracing are required before human translation can be assessed. Regulatory inclusion of spinal cord tissue on Russia's transplant list this year may accelerate first-in-human testing, yet methodological transparency remains essential given the small sample and absence of independent replication.