The aim of the study was to assess the integral outcomes of implantation biocompatible scaffold as the carrier of neural stem cells in the reconstructive surgery of open traumatic brain injury (TBI) by parameters of neurological and cognitive status of the animals in the experiment.Materials and Methods. Adult male C57BL/6 mice were injured with open-skull weight-drop method. 3D hydrogel scaffold based on modified chitosan in complex with hyaluronic acid was transplanted into the lesion cavity 1 week after TBI. Using a variety of behavioral and cognitive tests (modified neurological severity scores (mNSS), open field test as well as novel object recognition and passive avoidance tests) the short-and long-term neurological and memory functions sequelae induced by TBI were assessed. Magnetic resonance imaging was used to visualize the injury site.Results. Significant functional recovery was observed on both the mNSS and open field tests in the scaffold transplantation group compared to the control TBI group. In addition, enhanced improvement of short and long-term memory functions was found 5 months post injury. Magnetic resonance imaging data revealed that the scaffold transplantation result in decreasing of the volume of injury area compared to control TBI group and preventing the disruption of the neural networks of the brain. NeuroscieNce researchConclusion. Taken together, our findings indicated that transplantation of 3D biodegradable scaffold into injury cavity contributed to the preservation of volume in the damaged region in the first months after TBI which in turn led to a better functional recovery in the remote period.

The aim of the study was to evaluate the possibilities of transplantation of autologous neural progenitor cells from C57BL/6 mouse nasal olfactory lamina propria in the hydrogel based on low-, medium-, and high-molecular weight hyaluronic acid during a reconstructive operation after an open traumatic brain injury (TBI) in experiment.Materials and Methods. A reconstructive therapy was performed on the model of an open traumatic brain injury using the autologous neural progenitor cells from C57BL/6 mouse nasal olfactory lamina propria in a hydrogel based on high, medium, and low molecular hyaluronic acid 7 days after injury. Short-term and long-term impairments of neurological functions and memory due to TBI were assessed using a series of behavioral and cognitive tests (modified neurological severity score (mNSS)), open field test, novel object recognition test and passive avoidance behavior). High-field magnetic resonance tomography was used for visualization of a lesion cavity.Results. Implantation of autologous neural progenitor cells in the hydrogel based on high-molecular weight hyaluronic acid in contrast to low-and medium-molecular weight had a protective effect reducing neurological deficit and restoring motor functions, short-term and long-term memory in the posttraumatic period. The effect of hydrogel molecular weight on the morphological characteristics of the injury cavity was less effective during the autologous neural progenitor cells transplantation after TBI.Conclusion. Transplantation of autologous neural progenitor cells from C57BL/6 mouse nasal olfactory lamina propria in the hydrogel based on high-molecular weight hyaluronic acid into the injury focus after open brain trauma promotes functional recovery of reflex and cognitive behavior of animals in the posttraumatic period.

3Институт фотонных технологий, Федеральный научно-исследовательский центр «Кристаллография и фотоника» РАН, Москва, Троицк В работе на модели тяжелой открытой черепно-мозговой травмы проведено сравнительное изучение влияния времени имплантации 3D биодеградируемого скаффолда на восстановление поведенческих, ког-нитивных и иммунологических функций мышей в посттравматическом периоде. В работе показано, что имплантирование скаффолда через 1 неделю после ЧМТ, в сравнении с трансплантацией на 5 сутки, ока-зывает более быстрое восстановление структуры поведения животных и функций памяти. Трансплантация скаффолда в очаг повреждения на 7 сутки, в отличие от имплантации на 5 день, не вызывала активации воспалительных процессов в крови животных, а также не приводила к развитию аутоиммунных реакций. Таким образом, наиболее оптимальным временем имплантирования 3D скаффолда для функционального восстановления животных после тяжелой ЧМТ являлся 7 день после нанесения травмы. A comparative study of the influence of the time point implantation of 3D biodegradable scaffold on the restoration of behavioral, cognitive and immunological functions of mice in the posttraumatic period was carried out on the model of severe open traumatic brain injury. It is shown that scaffold implantation one week after TBI, in comparison with transplantation on 5th day, provides a faster recovery of animal behavior and memory functions. Activation of inflammatory processes in the blood of animals as well as the development of autoimmune reactions was not observed when scaffold was implanted into the lesion cavity on 7 day, unlike transplantation after5 days. Thus, the most optimal time point for 3D scaffold implantation for functional recovery of animals after severe traumatic brain injury was been on 7 day after injury.