Advantages and disadvantages of treatment of experimental ARDS by M2-polarized RAW 264.7 macrophages.

Innate immunity reactions are core to any immunological process, including systemic inflammation and such extremes as acute respiratory distress syndrome (ARDS) and cytokine storm. Macrophages, the key cells of innate immunity, show high phenotypic plasticity: depending on microenvironmental cues, they can polarize into M1 (classically activated, pro-inflammatory) or M2 (alternatively activated, anti-inflammatory). The anti-inflammatory M2 macrophage polarization-based cell therapies constitute a novel prospective modality. Systemic administration of 'educated' macrophages is intended at their homing in lungs in order to mitigate the pro-inflammatory cytokine production and reduce the risks of 'cytokine storm' and related severe complications. Acute respiratory distress syndrome (ARDS) is the main mortality factor in pneumonia including SARS-CoV-associated cases. This study aimed to evaluate the influence of infusions of RAW 264.7 murine macrophage cell line polarized towards M2 phenotype on the development of LPS-induced ARDS in mouse model. The results indicate that the M2-polarized RAW 264.7 macrophage infusions in the studied model of ARDS promote relocation of lymphocytes from their depots in immune organs to the lungs. In addition, the treatment facilitates expression of M2-polarization markers Arg1, Vegfa and Tgfb and decreases of M1-polarization marker Cd38 in lung tissues, which can indicate the anti-inflammatory response activation. However, treatment of ARDS with M2-polarized macrophages didn't change the neutrophil numbers in the lungs. Moreover, the level of the Arg1 protein in lungs decreased throughtout the treatment with M2 macrophages, which is probably because of the pro-inflammatory microenvironment influence on the polarization of macrophages towards M1. Thus, the chemical polarization of macrophages is unstable and depends on the microenvironment. This adverse effect can be reduced through the use of primary autologous macrophages or some alternative methods of M2 polarization, notably siRNA-mediated.

Morphological and molecular-biological features of glioblastoma progression in tolerant and susceptible to hypoxia Wistar rats.

Hypoxia is a major pathogenetic factor in many cancers. Individual resistance to suboptimal oxygen availability is subject to broad variation and its possible role in tumorigenesis remains underexplored. This study aimed at specific characterization of glioblastoma progression in male tolerant and susceptible to hypoxia Wistar rats. Hypoxia resistance was assessed by gasping time measurement in an 11,500 m altitude-equivalent hypobaric decompression chamber. Based on the outcome, the animals were assigned to three groups termed 'tolerant to hypoxia' (n = 13), 'normal', and 'susceptible to hypoxia' (n = 24). The 'normal' group was excluded from subsequent experiments. One month later, the animals underwent inoculation with rat glioblastoma 101.8 followed by monitoring of survival, body weight dynamics and neurological symptoms. The animals were sacrificed on post-inoculation days 11 (subgroup 1) and 15 (subgroup 2). Relative vessels number, necrosis areas and Ki-67 index were assessed microscopically; tumor volumes were determined by 3D reconstruction from histological images; serum levels of HIF-1α, IL-1ß, and TNFα were determined by ELISA. None of the tolerant to hypoxia animals died of the disease during observation period, cf. 85% survival on day 11 and 55% survival on day 15 in the susceptible group. On day 11, proliferative activity of the tumors in the tolerant animals was higher compared with the susceptible group. On day 15, proliferative activity, necrosis area and volume of the tumors in the tolerant to hypoxia animals were higher compared with the susceptible group. ELISA revealed no dynamics in TNFα levels, elevated levels of IL-1ß in the susceptible animals on day 15 in comparison with day 11 and tolerant ones. Moreover, there were elevated levels of HIF-1α in the tolerant animals on day 15 in comparison with day 11. Thus, the proliferative activity of glioblastoma cells and the content of HIF-1α were higher in tolerant to hypoxia rats, but the mortality associated with the tumor process and IL-1ß level in them were lower than in susceptible animals. Specific features of glioblastoma 101.8 progression in tolerant and susceptible to hypoxia rats, including survival, tumor growth rates and IL-1ß level, can become the basis of new personalized approaches for cancer diseases treatment in accordance to individual hypoxia resistance.

Comparative Analysis of the Paracrine Action of Neuronal and Glial Progenitor Cells Derived from Induced Human Pluripotent Stem Cells.

We performed comparative analysis of paracrine activity of neuronal and glial progenitors derived from induced pluripotent stem cells under conditions of hypoxia modeled by addition of cobalt dichloride. Neuronal and glial progenitors produced neuroprotective and neurotrophic effects on SHSY-5Y neuroblastoma cells in co-culture during the post-hypoxic recovery and reduced the number of apoptotic and necrotic cells. Moreover, they produced a neurotrophic effect and promote the formation and growth of neurites in neuroblastoma cells. The paracrine effect of glial progenitors was more pronounced, which can be explained by more intensive expression and secretion of neurotrophic factors in these cells.

Effect of Endothelial Cells on Angiogenic Properties of Multipotent Stromal Cells from the Umbilical Cord during Angiogenesis Modeling in the Basement Membrane Matrix.

Short-term cell culturing on basement membrane matrix is a common and very convenient in vitro model of angiogenesis. We studied the possibility of interaction of multipotent stromal cells from the umbilical cord and Ea.hy926 endothelial cells on this model at the early and late periods of the experiment. Multipotent stromal cells alone and in combination with endothelial cells formed an unstable tubular network. Clusters formed after its disassembling later became the sprouting centers in co-culture of the two cell types, but not in pure culture of multipotent stromal cells. Multipotent stromal cells with CD31+ phenotype constitute the structural basis of newly formed stable 3D capillary-like network. Prolongation of the time of culturing and combination of the two in vitro models of angiogenesis (tubulogenesis and sprouting) allowed more complete assessment of the angiogenic potential of multipotent stromal cells.

Effect of multipotent stromal cells on the function of cell mitochondria in regenerating liver.

Intrasplenic allogeneic transplantation of multipotent stromal cells from the umbilical cord stimulates hepatocyte proliferation and promotes recovery of liver weight in rats after subtotal resection (80% organ weight). It can be hypothesized that this effect of multipotent stromal cells is due to more rapid recovery of the number of mitochondria and normalization of mitochondrial function of liver hepatocytes.