Evaluation of human mononuclear umbilical cord blood cells systemic administration efficiency in the acute period of experimental severe spinal cord injury

Aim. To evaluate the efficiency of systemic (intravenous) application of cryopreserved human umbilical cord blood mononuclear cells (HUCBCs) in animal models of acute contusion spinal cord injury for the restoration of hind limb motor function and formation of posttraumatic cysts using clinically significant examination methods.Materials and methods. Adult female Sprague–Dowley rats were used for the study. Severe acute contusion spinal cord injury model was performed using standard “weight‑drop” method. All samples of cryopreserved HUCBCs concentrate were prestored prior to infusion for 3 to 4 years at –196 °C. Hind limbs motor function was evaluated using open‑field technique and standard BBB testing system. Magnetic resonance scanning was performed using high‑field magnetic resonance CleanScan 7.0 T tomography (Bruker BioSpin, Germany).Results. Intravenous infusions of HUCBCs were performed on Day 1 following acute severe spinal cord injury. Motor function assessment demonstrated significant (p <0.05) improvement of hind limbs motor function (up to 40–50 %) comparing to self‑healing outcomes. Moreover, by the Days 4 and 5 after severe spinal cord injury, the volume of posttraumatic cystic cavity decreases significantly (up to 40 %) (p <0.05).Conclusion. The obtained results demonstrated that cryopreserved HUCBCs can be used as an effective source for cell therapy of acute contusion spinal cord injury.