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Aim. To study antitumor cytotoxic effect of CAR-T NKG2D and CAR-T anti-CD19 in vitro and in vivo in order to compare antitumor activity of chimeric antigen receptors (CAR) with different structural and functional properties. Materials & Methods. CAR constructions were produced by molecular cloning. CAR-T cell populations were obtained by transduction of healthy donor T-lymphocytes with recombinant lentiviral particles coding CAR NKG2D or CD19 target antigen CAR sequences. CAR-T cell proportion was assessed by FusionRed fluorescence and EGFR membrane receptor imaging. Specific in vitro cytotoxic activity of CAR-T effector cells was analyzed by Real-Time Cytotoxicity Assay (RTCA) during co-cultivation with HeLa_CD19 target cell line using xCELLigence. Interferon-Y (IFN-y) synthesis in vitro and in vivo along with the degree of cytotoxic effect were analyzed by immunoassay of culture medium of co-cultivated effector cells and target cells as well as isolated auto-plasma from the peripheral blood of mice. To assess the in vivo functional activity, CAR-T cell populations were infused into immunodeficient NSG-SGM3 mice (10 000 000 cells/mouse) 12 days after HeLa_CD19 cell injection and confirmation of engraftment and tumor growth. Upon euthanasia, tumors were removed and fixed in paraffin to prepare histological sections. CAR-T cell tumor infiltration was assessed by CD3 antigen immunohistochemical staining. Results. The highest ligand (molecules MICA, ULBP1/2/3/4/5/6) expression levels were detected in HeLa cell line. The obtained NKG2D CAR-T cells showed a considerable cytotoxic activity against HeLa_CD19 target line (cell index [CI] = 1.27), which was, however, twice as low as that of CAR-T anti-CD19 (CI = 0.60) (p = 0.0038). IFN-y level during co-cultivation of CAR-T anti-CD19 with HeLa_CD19 at the ratio of Е/Т = 1:1 was 64,852 pcg/mL, which was 3.5 times higher than IFN-y level during co-cultivation of CAR-T NKG2D with HeLa_CD19 (18,635 pcg/mL) (p = 0.0360). The degree of tumor infiltration by CAR-T anti-CD19 cells was higher than that by CAR-T NKG2D. The absence of NKG2D proliferating CAR-T cells in mice peripheral blood confirms their low persistence. IFN-y concentration in mice auto-plasma was 11.89 pcg/mL after CAR-T anti-CD19 infusion and 0.57 pcg/mL after CAR-T NKG2D infusion (p = 0.0079). The mean weight of tumor xenografts in experimental groups 10 days after CAR-T anti-CD19 injection was 0.72 g (p = 0.0142), after Т-lymphocyte and NKG2D CAR-T cell infusions it was 2.12 g and 1.2 g, respectively. Conclusion. CAR-T anti-CD19 cells are characterized by more pronounced cytotoxic effect under both in vitro and in vivo experimental conditions compared with CAR-T NKG2D cells. The degree of CAR-T anti-CD19 proliferation and their infiltration in mice xenograft models is considerably higher than the levels reached with NKG2D CAR-T cell injections. A single CAR-T NKG2D injection results only in short-term tumor reduction.

Background. Up to the present the survival rates of acute myeloid leukemia (AML) patients have remained low. A successful AML management presupposes generating personalized models of the disease. The most promising research activity in this field is creation of AML patient-derived xenograft models using the advanced strain of immunodeficient humanized NSG-SGM3 mice. Aim. To generate AML patient-derived xenograft models using immunodeficient NSG-SGM3 mice. Materials & Methods. The creation of PDX models was based on bone marrow aspirates taken from 4 patients with newly diagnosed AML who were treated at the V.A. Almazov National Medical Research Center. Patient-derived tumor cells were transplanted to NSG-SGM3 mice. Test experiment consisted in injecting AML cells OCI-АМL2 and HL60 in NSG-SGM3 mice. The efficacy of tumor engraftment was evaluated in terms of physical condition of animals and laboratory tests (blood count, blood smear, PCR, and flow cytofluorometry). Results. The engraftment of applied tumor cells derived from AML patients was achieved in half (2 out of 4) of the transplanted tumor samples. In mice with successful transplantation leukocytosis was reported. Blast cells were identified in peripheral blood on Day 30 after transplantation. The mice with injected AML cells OCI-АМL2 and HL60 showed a more aggressive course of disease. Among tested approaches to evaluate tumor engraftment in mouse recipients, the PCR method was marked by highest sensitivity. Conclusion. The use of immunodeficient humanized NSG-SGM3 mice enables successful generation of AML patient-derived xenograft models.

NK-cells as innate immunity elements manifest key reactions of antitumor immune response. NKG2D is an activating transmembrane receptor of NK-cells which is responsible for cytotoxicity initiation in response to the binding of specific ligands of genetically modified cells. Selective expression of NKG2D ligands provides a unique perspective on the therapy of wide variety of tumors. Acute myeloid leukemias (AML) are malignant hematological tumors with a high relapse risk. Due to the complexity of AML treatment strategy it is necessary to develop new approaches to tumor elimination using novel genetic constructs. Currently available CAR T-cell drugs with NKG2D receptor are successfully subjected to clinical studies in AML patients and prove their high therapeutic potential.

Aim. To identify mutations in IDH1/IDH2, DNMT3A, and ASXL1 genes responsible for genome epigenetic regulation and their co-occurrence with FLT3, NPM1, and RUNX1 mutations in newly diagnosed adult acute myeloid leukemias (AML). Materials & Methods. The study included 56 patients with newly diagnosed AML treated at the VA Almazov National Medical Research Center. Among them there were 34 men and и 22 women aged 18-76 years (median 46 years). Mutation status of IDH1, IDH2, DNMT3A, and ASXL1 genes of epigenetic regulation was assessed by Sanger sequencing method. Molecular genetic analysis of FLT3, NPM1, and RUNX1-RUNX1T1 genes was performed using commercial kits. Results. Mutations in epigenetic regulation genes were detected in 14 (25 %) out of 56 patients. Mutation prevalence was not associated with risk groups (p = 0.072). IDH1/2 mutations were identified in 15.6 % of patients and were significantly oftener observed concurrent with NPM1 mutations (62.5 %; p = 0.01) compared to patients with wild-type IDH1/2. In most patients IDH1/2 mutations were associated with normal karyotype (p = 0.002). The DNMT3A (R882) mutation was identified in 4 (7.1 %) out of 56 patients within the analyzed group. In 6 patients (11.1 %) ASXL1 mutations were detected co-occurring with RUNX1-RUNX1T1 and FLT3-ITD mutations. Conclusion. Mutations in epigenetic regulation genes are often identified in AML patients and can be concurrent with abnormalities in NPM1, FLT3 и RUNX1 genes.

Myeloid sarcoma, also known as chloroma or granulocytic sarcoma, is a rare disease characterized by the proliferation of immature myeloid cells in extramedullary lesions. Chloroma is more commonly observed in patients with acute myeloid leukemias, other myeloproliferative neoplasms, or myelodysplastic syndrome. However, it can also manifest itself as solitary tumor. Sarcoma can develop in different organs and tissues, but most frequently it appears in lymph nodes, soft tissues, and bones. Myeloid sarcoma with primary gynecological lesion is very rarely mentioned. In literature cases of cervical lesions are described. The present article summarizes the literature data concerning different aspects of myeloid sarcoma diagnosis and treatment. The issue under discussion is the role of chemotherapy, radiotherapy, surgery, and bone marrow transplantation in the treatment of this malignant tumor. It appears that whatever the primary tumor localization, the best treatment options are chemotherapy and allogeneic bone marrow transplantation (allo-BMT). A promising trend is the use of novel targeted drugs improving outcomes of treatment. The article provides a case report of a female patient with cervical myeloid sarcoma and concomitant bone marrow involvement, as well as the description of clinical course, diagnosis, and treatment. The patient received chemotherapy with subsequent allo-BMT. The pre-transplant therapy enabled allo-BMT with the deepest response possible. The patient achieved PET-and MRD-negative complete remission of cervical myeloid sarcoma and bone marrow.

Background. FLT3 gene is an important prognostic molecular marker in acute myeloid leukemia (AML). However, the detection of FLT3 mutations presents a challenge. Aim. To compare techniques used for the detection of FLT3 mutations, and to develop a test-system based on polymerase chain reaction (PCR) for quick and reliable determination of FLT3 mutation status. Materials & Methods. Bone marrow samples obtained from AML patients were subjected to examination. To detect FLT3-ITD и FLT3-TKD mutations PCR was performed with subsequent agarose gel electrophoresis visualization. The results were verified by Sanger sequencing. The data obtained using our test-system were compared with widely applied commercial kit ‘FLT3 Mutation Assay for Gel Detection’ by Invivoscribe. Results. To determine the FLT3 mutation status a PCR test was developed. This technique was validated on 22 bone marrow samples obtained from AML patients. FLT3-ITD mutation was detected in 4 patients, 3 patients showed FLT3-TKD mutation. In 1 patient both mutations were identified. These results fully corresponded to the molecular genetic analysis of FLT3, performed by ‘FLT3 Mutation Assay for Gel Detection’. The chosen technique was validated using Sanger sequencing data analysis. Conclusion. The article offers the review of all existing FLT3 mutation screening techniques and describes the experience of developing the PCR test for FLT3-ITD and FLT3-TKD mutation detection. The chosen technique is affordable and easy to use compared with the others. The present study with its applied nature can provide guidance for both doctors and researchers.

Background. Cytokines are considered as important factors that enhance the efficacy of CAR-T cell therapy. Besides, they are key elements of the pathogenesis of cytokine release syndrome and neurotoxicity in applying the CAR-T technology. However, cytokine effects in the context of CAR-T therapy have not yet been properly studied. Aim. To quantitatively assess cytokine secretion using multiplex assay with co-incubation of anti-CD19 CAR-T lymphocytes with epithelial HeLa and A431 cell lines expressing CD19 on their surface. Materials & Methods. T-lymphocytes were transduced with the lentiviral vector containing anti-CD19-CAR gene. CAR expression was tested based on GFP reporter using flow cytometry. To confirm a specific CAR-T cell activation response to tumor antigen, the levels of interleukin-2, interferon-γ, and tumor necrosis factor-α were measured by means of immunoassay. Cytotoxic activity of CAR-T lymphocytes obtained was examined with their direct co-culturing with target cells. The levels of cytokines isolated prior to and after incubation of targets with CAR-T cells were compared using multiplex assay. Results. The level of some proinflammatory cytokines (interleukin-6, interleukin-1β, interferon-γ) (P < 0.01) increased. The difference in the levels of anti-inflammatory cytokines (interleukin-4, interleukin-10) was inconsiderable, and in the HeLa cell line experiment it was insignificant (p > 0.05). The concentration of granulocyte-macrophage colony-stimulating factor (GM-CSF) was many times higher after incubation with CAR-T lymphocytes (p < 0.01). Conclusion. The trial revealed multiple enhancement of GM-CSF, one of the key elements of the pathogenesis of cy tokine release syndrome and CAR-T-associated neurotoxicity. The results of further studies of GM-CSF can contribute to improving the efficacy of CAR-T therapy with considerably lower toxicity.

Aim. To compare different methods of lentivirus concentration in order to select the best way of providing high-level transduction for generating laboratory CAR-T cells. Materials & Methods. Concentration of lentiviral supernatant was carried out by 4 methods: ultrafiltration, ultracentrifugation, polyethylene glycol (PEG), water-soluble non-ionic polymer, precipitation method, and ion-exchange chromatography. Functional viral titer was determined by mCherry reporter protein expression in the transduced HeLa cell line as well as by rapid immunochromatographic (IC) tests. Physical titer was determined by ELISA. Transduction efficiency of healthy donor’s T-lymphocytes was assessed by flow cytometry with respect to signal intensity of reporter protein FusionRed. Functional activity of generated anti-CD19 CAR-T was evaluated by microscopy after co-cultivation with CD19-HeLa cell line as well as subsequent cytokine testing. Results. Lentivirus purification and concentration by ultrafiltration provided the greatest number of transduced cells, i.e. 84.7 %. Methods of ultracentrifugation, PEG precipitation, and ion-exchange chromatography yielded 56.08 %, 74.22 %, and 21.05 % of T-cell transduction, respectively. Results of rapid IC tests were comparable (г = 0.91) with cell line titer data. The mean T-cell transduction efficiency was 59.55 % ± 2.94 %, and its maximum reached 76.26 %. Conclusion. The focus was laid on optimization of CAR-T cell production during the generation of lentiviral vectors and their purification. Ultrafiltration was selected as the best method of lentiviral supernatant concentration to efficiently transduce T-lymphocytes and to generate functional CAR-T cell population.

Background. The most promising variant of adoptive immunotherapy of the B-line oncohematological diseases includes the use of cells with the chimeric antigen receptor (CAR T-cells), that showed extraordinary results in clinical studies. Aim. To manufacture CAR T-cells for the clinical use and to study their cytotoxicity in vitro. Methods. Human T-lymphocytes were transduced by the lentiviral vector containing anti-CD19-CAR, RIAD, and GFP genes. The T-cell transduction efficacy was assessed on the basis of GFP protein signal by flow cytometry. Propidium iodide was used to analyse the cell viability. Cytotoxic activity of the manufactured CAR T-cells was studied in the presence of the target cells being directly co-cultivated. Analysis of the number and viability of CAR T-cells and cytokine expression was performed by flow cytometry. Results. The viability of the transduced T-cells and GFP expression reached 91.87 % and 50.87 % respectively. When cultured in the presence of IL-2 and recombinant CD19 (the target antigen), the amount of CAR-T after 120 h of the process was 1.4 times larger compared with the period of 48 h. In the cytotoxic test of co-cultivation CART with the K562-CD19+ cells the percentage of CAR-T increased to 57 % and 84.5 % after 48 h and 120 h of exposure respectively. When cultured with the K562 cells (test line not expressing CD19) the number of CAR T-cells decreased to 36.2 % within 48 h while the number of K562 cells increased to 58.3 %. The viability of target cells in the experimental and control groups was 3.5 % and 36.74 % respectively. Comparison of IL-6 level in the control and experimental groups revealed that the differences are insignificant, as opposed to the level of other cytokines (IFN-y, IL-2, TNF) which proved to be different in both groups. Conclusion. The present work resulted in the production of anti-CD19 CAR T-cells with adequate viability. The in vitro model demonstrated their cytotoxicity. Manufacturing of CAR T-cells for clinical use is the first step of the development of adoptive immunotherapy in the Russian Federation.

Report reviews the application of modern phenomenological and holistic models as well as innovative horizontal drilling technologies and interpretation 3D seismic to improve oil recovery of tight oil carbonate reservoirs. The new scientific model and an integrated approach in the development of unconventional carbonate reservoirs with low porosity. The systems was first implemented during the drilling of two horizontal wells in USA with the close cooperation of Russian, American and Australian experts. The concept of the model is aimed to identify high permeability fracture zones before drilling of the wells, their optimal crossing by the open horizontal hole and preservation in the process of drilling the primary of permeability of fractures, created by the nature itself, which can be considered as an alternative to multistage fracturing and other technologies which are commonly use in the development of hydrocarbons in tight oil and gas reservoirs. Received in the process of joint work results have been planning to be used not only to drill new wells to tight carbonate reservoirs and shales in South Texas, but also in similar fields in tight reservoirs in Western and Eastern Siberia, Timan-Pechora and Volga-Urals oil and gas basins in Russia as well as abroad.

The effectiveness of gas recirculation and simplicity of its implementation in carbonate reservoirs can determine that increasing in production rate can be carried out at the stage of drafting development and operation of oil fields. In this work, a new model was developed to consider the effect of gas recycling on production indicators depending on the amount of gas injection by Eclipse (Schlumberger) software. This developed model has been used for considering the reservoir pressure, gas oil ratio, recovery factor and water cut of the carbonate reservoir during its long period of production. The observations showed that model has optimum time period at high amount of recycling into the synthetic carbonate reservoir. Recovery factor of the reservoir was increased twenty times more than the case without injection after the defined production time. The optimum reservoir pressure is determined by this simulation method with minimum water cut. Also, in case of gas recycling, the reservoir pressure is maintained constantly over the production time that it leads to increase the efficiency for production and keep it in a desirable level during the time that In fact it’s one of the noticeable points for keeping and preserving the reservoir during its production time

Quantum-mechanical calculations are carried out for the non-linear current in the bulk of simple metals. The energy bands and matrix elements for optical transitions are calculated using a two-band model which is known to give accurate results for the description of the linear dielectric response of these systems. The frequency dependence of the isotropic and anisotropic components of the non-linear polarizability tensor shows characteristic resonances due to various interband transitions in the optical region. In the adiabatic limit, excellent agreement is obtained with results derived within the Boltzmann equation approach. The emitted harmonic radiation is calculated to illustrate the influence of the non-linear volume current on the variation of the intensity with polar and azimuthal angles of incidence. Using recent experimental data for optical second-harmonic generation from Al(111) and the calculated bulk polarizability, predictions are made concerning the magnitude and relative phase of the surface anisotropy.

The surface of originally smooth silver electrodes is studied by means of reflected second harmonic (SH) generation and scanning tunneling microscopy after electrochemical etching of N monoatomic surface layers ( N ∼ 0minus;10). At N ∼ 1 a generation of surface enhanced, diffuse, and depolarized SH is observed, and a distinct superatomic (of the scale ∼ 10 A) granular roughness is detected on the electrode surface. The fluctuation electromagnetic mechanism is proposed to explain the surface enhancement of diffuse and depolarized SH component: the effect is interpreted as resulting from exciton of local plasmons in irregular surface structures formed in the process of etching.

We present results of the first calculation of the surface anisotropic contribution to second harmonic generation for a realistic metal surface. Although the anisotropic second-order response has its origin at the surface, the main contribution to the surface anisotropic parameter ξ has a remarkably large penetration depth. Moreover, the long-range oscillations of the anisotropic nonlinear surface current deep inside aluminum are found. The surface anisotropic secondorder polarizability ξ is in a good qualitative agreement with recent experimental data on clean Al(111) at ħω=1.17 eV. A resonant enhancement of the SHG anisotropy is predicted for ω and 2ω close to 1.5 eV—the energy gap in bulk aluminum along the [100] directions. A significant decrease of the surface anisotropic response in comparison with the isotropic one is found for ω≥1.5 eV.

Hydrocarbon exploration in carbonate and shale deposits seems to be less efficient than exploration of terrigenous reservoirs in the Timan-Pechora Basin. This disparity is due to a number of factors, chief of which are complexity of geological structure in areas of carbonate and shale reservoirs and complexity and unpredictability of porosity and permeability. Therefore, considerable heterogeneity of carbonate and shale reservoirs reduces efficiency of prospecting, exploration and engineering of oil deposits in carbonate reservoirs. The study of carbonate and shale reservoirs, which formed in different periods in the Timan-Pechora Basin, has highlighted importance of tectonic fractures in the evolution of complex reservoirs. These fractures are formed during local tectonic folding. The pervasive faults and fractures generated during these folding episodes in carbonate and shale rocks promote active filtration and leaching by surface and subsurface waters, containing corrosive components (CO2, H2S, etc.). Highly permeable fracture zones, which are called sweet spots, affect the processes of hydrocarbon migration and oil-gas accumulation. Exploitation experience at Usinsk, Kharyaga, Upper Vozey and other oil fields has shown, that sweet spots influence processes of oil pool formation. It is necessary to take into consideration such sweet spots when the optimal system of reservoir engineering is chosen. An integrated exploration method has been developed for finding and delineation of sweet spots. This method includes analisys of seismic and gravity exploration data, aero-space photo-interpretation, well logging data, results of core and drilling data interpretation. The use of integrated exploration is proven to be effective in finding sweet spots in carbonate and shale reservoirs. It has also enabled greater understanding of the complexities, geometry, and tectonic relationships of sweet spots formation.

In this study, the description of Enhance Oil Recovery effectivity (EOR) of surfactant denominated reagent A, at the secondary waterflooding process for heavy oil recovery from fractured-porous carbonate core samples were investigated experimentally. For this experiment have been selected two cores, 14,75 cm long and 3 cm diameter were stacked in a long 3D confining core holder. In the first step, cores have been saturated by brine. In the second step, cores have been saturated of heavy oil through the water-saturated core sample for two-phase saturation. In the third step, we provided the injecting of water through the core sample for measuring oil recovery factor (by cold water 20ºC) simulating the primary recovery at these conditions. In the fourth step, was injected of 2 pore volumes of Reagent A through the core sample for measuring oil recovery factor (by reagent A) and simulating the slug. In the fifth step and final, was injected water through the core sample for measuring full oil recovery factor (by cold water) after slug of Reagent A. In the course of experiments, oil and water productions, pressure and temperatures of system were monitored and regulated carefully.