We have designed a novel two-component matrix (SPRPix) for the encapsulation of directly reprogrammed human neural precursor cells (drNPC). The matrix is comprised of 1) a solid anisotropic complex scaffold prepared by electrospinning a mixture of recombinant analogues of the spider dragline silk proteins – spidroin 1 (rS1/9) and spidroin 2 (rS2/12) - and polycaprolactone (PCL) (rSS-PCL), and 2) a “liquid matrix” based on platelet-rich plasma (PRP). The combination of PRP and spidroin promoted drNPC proliferation with the formation of neural tissue organoids and dramatically activated neurogenesis. Differentiation of drNPCs generated large numbers of βIII-tubulin and MAP2 positive neurons as well as some GFAP-positive astrocytes, which likely had a neuronal supporting function. Interestingly the SPRPix microfibrils appeared to provide strong guidance cues as the differentiating neurons oriented their processes parallel to them. Implantation of the SPRPix matrix containing human drNPC into the brain and spinal cord of two healthy Rhesus macaque monkeys showed good biocompatibility: no astroglial and microglial reaction was present around the implanted construct. Importantly, the human drNPCs survived for the 3 month study period and differentiated into MAP2 positive neurons. Tissue engineered constructs based on SPRPix exhibits important attributes that warrant further examination in spinal cord injury treatment.

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CEA as an initial management strategy could reduce the risk of death and major cerebrovascular events when added to MMT.

Over many decades, constructing genetically and phenotypically stable lines of neural stem cells (NSC) for clinical purposes with the aim of restoring irreversibly lost functions of nervous tissue has been one of the major goals for multiple research groups. The unique ability of stem cells to maintain their own pluripotent state even in the adult body has made them into the choice object of study. With the development of the technology for induced pluripotent stem cells (iPSCs) and direct transdifferentiation of somatic cells into the desired cell type, the initial research approaches based on the use of allogeneic NSCs from embryonic or fetal nervous tissue are gradually becoming a thing of the past. This review deals with basic molecular mechanisms for maintaining the pluripotent state of embryonic/induced stem and reprogrammed somatic cells, as well as with currently existing reprogramming strategies. The focus is on performing direct reprogramming while bypassing the stage of iPSCs which is known for genetic instability and an increased risk of tumorigenesis. A detailed description of various protocols for obtaining reprogrammed neural cells used in the therapy of the nervous system pathology is also provided.

Introduction. The lack of effective aetiotropic therapy of COVID-19 prompted researchers around the world searching for various methods of SARS-CoV-2 elimination, including convalescent plasma. The aim of this work was to study the safety and efficacy of severe COVID-19 treatment with convalescence plasma containing specific antibodies to the receptor binding domain (RBD) of SARS-CoV-2 S protein in a titer of at least 1: 1000. Methods. A single-center, randomized, prospective, clinical study performed at the FRCC FMBA of Russia with the participation of 85 patients who were stratified in two groups. The first group contains 20 critically ill patients who are on mechanical ventilation; Results. The use of plasma of convalescents in patients with severe COVID-19 with mechanical ventilation does not affect the disease outcome in these patients. Mortality rate in this group was 60%, which corresponds to the average mortality of patients on mechanical ventilation in our hospital. In the second group clinical improvement was detected in 75% and 51%, for convalescent and normal plasma respectively. Of the 46 people who received convalescent plasma, three patients (6.5%) were transferred to mechanical ventilation, two of whom died. In the group receiving non-immune plasma, the need for mechanical ventilation also arose in three patients (15%), of which two died. The hospital mortality in the group of convalescent plasma was 4.3%, which is significantly lower than the average COVID-19 hospital mortality in our Center (6.73%) and more than two times lower than the hospital mortality in the control group (n = 150), matched by age and by the disease severity. Conclusions. Thus, we demonstrated relative safety of convalescent plasma transfusion and the effectiveness of such therapy for COVID-19 at least in terms of the survival of patients with severe respiratory failure without mechanical ventilation. In the absence of bioengineered neutralizing antibodies and effective aetiotropic therapy, the use of hyperimmune convalescent plasma is the simplest and most effective method of specific etiopathogenetic therapy using forms of COVID-19.

Ischemic heart disease (IHD) has been recognized as the main cause of mortality in the modern world. Application of cell therapy technologies for the IHD treatment has been actively studied from the beginning of 2000s. The review is dedicated to the use of mesenchymal stem cells (MSC) in the therapy of IHD. The strategies of the MSC modification in vitro for improvement of their regenerative potential are extensively discussed, including preconditioning to enhance the cell survival, boosting their paracrine effect, manipulating their cardiomyogenic differentiation. The optimization of the MSC delivery and opportunities related to the use of biomaterials as cell carriers are also discussed. The results of the most important clinical studies on the MSC-based IHD therapy are presented, including those completed and published in the literature and the ongoing clinical trials registered at clinicaltrials.gov by June, 2018.

The interaction of neural progenitor cells (NPCs) with the extracellular matrix (ECM) plays an important role in neural tissue regeneration. Understanding which motifs of the ECM proteins are crucial for normal NPC adhesion, proliferation, and differentiation is important in order to create more adequate tissue engineered models of neural tissue and to efficiently study the central nervous system regeneration mechanisms. We have shown earlier that anisotropic matrices prepared from a mixture of recombinant dragline silk proteins, such as spidroin 1 and spidroin 2, by electrospinning are biocompatible with NPCs and provide good proliferation and oriented growth of neurites. This study objective was to find the effects of spidroin-based electrospun materials, modified with peptide motifs of the extracellular matrix proteins (RGD, IKVAV, and VAEIDGIEL) on adhesion, proliferation, and differentiation of directly reprogrammed neural precursor cells (drNPCs). The structural and biomechanical studies have shown that spidroin-based electrospun mats (SBEM), modified with ECM peptides, are characterized by a uniaxial orientation and elastic moduli in the swollen state, comparable to those of the dura mater. It has been found for the first time that drNPCs on SBEM mostly preserve their stemness in the growth medium and even in the differentiation medium with brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor, while addition of the mentioned ECM-peptide motifs may shift the balance toward neuroglial differentiation. We have demonstrated that the RGD motif promotes formation of a lower number of neurons with longer neurites, while the IKVAV motif is characterized by formation of a greater number of NF200-positive neurons with shorter neurites. At the same time, all the studied matrices preserve up to 30% of neuroglial progenitor cells, phenotypically similar to radial glia derived from the subventricular zone. We believe that, by using this approach and modifying spidroin by various ECM-motifs or other substances, one may create an in vitro model for the neuroglial stem cell niche with the potential control of their differentiation.

The surgical management of colorectal metastasis is becoming a widespread practice in oncology. Synchronous resection of metastasis together with invaded major vessels (aorta) is still considered an extremely aggressive procedure. We demonstrate that en bloc resection of invaded aorta and paraaortic lymph node metastasis can be safely performed. The literature from experiences with similar techniques is also discussed.