Репозиторий Университета

© 2021, The Author(s). Background: CARs are simulated receptors containing an extracellular single-chain variable fragment (scFv), a transmembrane domain, as well as an intracellular region of immunoreceptor tyrosine-based activation motifs (ITAMs) in association with a co-stimulatory signal. Main body: Chimeric antigen receptor (CAR) T cells are genetically engineered T cells to express a receptor for the recognition of the particular surface marker that has given rise to advances in the treatment of blood disorders. The CAR T cells obtain supra-physiological properties and conduct as “living drugs” presenting both immediate and steady effects after expression in T cells surface. But, their efficacy in solid tumor treatment has not yet been supported. The pivotal challenges in the field of solid tumor CAR T cell therapy can be summarized in three major parts: recognition, trafficking, and surviving in the tumor. On the other hand, the immunosuppressive tumor microenvironment (TME) interferes with T cell activity in terms of differentiation and exhaustion, and as a result of the combined use of CARs and checkpoint blockade, as well as the suppression of other inhibitor factors in the microenvironment, very promising results were obtained from the reduction of T cell exhaustion. Conclusion: Nowadays, identifying and defeating the mechanisms associated with CAR T cell dysfunction is crucial to establish CAR T cells that can proliferate and lyse tumor cells severely. In this review, we discuss the CAR signaling and efficacy T in solid tumors and evaluate the most significant barriers in this process and describe the most novel therapeutic methods aiming to the acquirement of the promising therapeutic outcome in non-hematologic malignancies.

© 2021, The Author(s). Background: CARs are simulated receptors containing an extracellular single-chain variable fragment (scFv), a transmembrane domain, as well as an intracellular region of immunoreceptor tyrosine-based activation motifs (ITAMs) in association with a co-stimulatory signal. Main body: Chimeric antigen receptor (CAR) T cells are genetically engineered T cells to express a receptor for the recognition of the particular surface marker that has given rise to advances in the treatment of blood disorders. The CAR T cells obtain supra-physiological properties and conduct as “living drugs” presenting both immediate and steady effects after expression in T cells surface. But, their efficacy in solid tumor treatment has not yet been supported. The pivotal challenges in the field of solid tumor CAR T cell therapy can be summarized in three major parts: recognition, trafficking, and surviving in the tumor. On the other hand, the immunosuppressive tumor microenvironment (TME) interferes with T cell activity in terms of differentiation and exhaustion, and as a result of the combined use of CARs and checkpoint blockade, as well as the suppression of other inhibitor factors in the microenvironment, very promising results were obtained from the reduction of T cell exhaustion. Conclusion: Nowadays, identifying and defeating the mechanisms associated with CAR T cell dysfunction is crucial to establish CAR T cells that can proliferate and lyse tumor cells severely. In this review, we discuss the CAR signaling and efficacy T in solid tumors and evaluate the most significant barriers in this process and describe the most novel therapeutic methods aiming to the acquirement of the promising therapeutic outcome in non-hematologic malignancies.

Despite many recent advances on cancer novel therapies, researchers have yet a long way to cure cancer. They have to deal with tough challenges before they can reach success. Nonetheless, it seems that recently developed immunotherapy-based therapy approaches such as adoptive cell transfer (ACT) have emerged as a promising therapeutic strategy against various kinds of tumors even the cancers in the blood (liquid cancers). The hematological (liquid) cancers are hard to be targeted by usual cancer therapies, for they do not form localized solid tumors. Until recently, two types of ACTs have been developed and introduced; tumor-infiltrating lymphocytes (TILs) and chimeric antigen receptor (CAR)-T cells which the latter is the subject of our discussion. It is interesting about engineered CAR-T cells that they are genetically endowed with unique cancer-specific characteristics, so they can use the potency of the host immune system to fight against either solid or liquid cancers. Multiple myeloma (MM) or simply referred to as myeloma is a type of hematological malignancy that affects the plasma cells. The cancerous plasma cells produce immunoglobulins (antibodies) uncontrollably which consequently damage the tissues and organs and break the immune system function. Although the last few years have seen significant progressions in the treatment of MM, still a complete remission remains unconvincing. MM is a medically challenging and stubborn disease with a disappointingly low rate of survival rate. When comparing the three most occurring blood cancers (i.e., lymphoma, leukemia, and myeloma), myeloma has the lowest 5-year survival rate (around 40%). A low survival rate indicates a high mortality rate with difficulty in treatment. Therefore, novel CAR-T cell-based therapies or combination therapies along with CAT-T cells may bring new hope for multiple myeloma patients. CAR-T cell therapy has a high potential to improve the remission success rate in patients with MM. To date, many preclinical and clinical trial studies have been conducted to investigate the ability and capacity of CAR T cells in targeting the antigens on myeloma cells. Despite the problems and obstacles, CAR-T cell experiments in MM patients revealed a robust therapeutic potential. However, several factors might be considered during CAR-T cell therapy for better response and reduced side effects. Also, incorporating the CAT-T cell method into a combinational treatment schedule may be a promising approach. In this paper, with a greater emphasis on CAR-T cell application in the treatment of MM, we will discuss and introduce CAR-T cell’s history and functions, their limitations, and the solutions to defeat the limitations and different types of modifications on CAR-T cells.

In recent decades, a new method of cellular immunotherapy was introduced based on engineering and empowering the immune effector cells. In this type of immunotherapy, the immune effector cells are equipped with chimeric antigen receptor (CAR) to specifically target cancer cells. In much of the trials and experiments, CAR-modified T cell immunotherapy has achieved very promising therapeutic results in the treatment of some types of cancers and infectious diseases. However, there are also some considerable drawbacks in the clinical application of CAR-T cells although much effort is in progress to rectify the issues. In some conditions, CAR-T cells initiate over-activated and strong immune responses, therefore, causing unexpected side-effects such as systemic cytokine toxicity (i.e., cytokine release syndrome), neurotoxicity, on-target, off-tumor toxicity, and graft-versus-host disease (GvHD). To overcome these limitations in CAR-T cell immunotherapy, NK cells as an alternative source of immune effector cells have been utilized for CAR-engineering. Natural killer cells are key players of the innate immune system that can destroy virus-infected cells, tumor cells, or other aberrant cells with their efficient recognizing capability. Compared to T cells, CAR-transduced NK cells (CAR-NK) have several advantages, such as safety in clinical use, non-MHC-restricted recognition of tumor cells, and renewable and easy cell sources for their preparation. In this review, we will discuss the recent preclinical and clinical studies, different sources of NK cells, transduction methods, possible limitations and challenges, and clinical considerations.

Acute myeloid leukemia (AML) is a serious, life-threatening, and hardly curable hematological malignancy that affects the myeloid cell progenies and challenges patients of all ages but mostly occurs in adults. Although several therapies are available including chemotherapy, allogeneic hematopoietic stem cell transplantation (alloHSCT), and receptor-antagonist drugs, the 5-year survival of patients is quietly disappointing, less than 30%. alloHSCT is the major curative approach for AML with promising results but the treatment has severe adverse effects such as graft-versus-host disease (GVHD). Therefore, as an alternative, more efficient and less harmful immunotherapy-based approaches such as the adoptive transferring T cell therapy are in development for the treatment of AML. As such, chimeric antigen receptor (CAR) T cells are engineered T cells which have been developed in recent years as a breakthrough in cancer therapy. Interestingly, CAR T cells are effective against both solid tumors and hematological cancers such as AML. Gradually, CAR T cell therapy found its way into cancer therapy and was widely used for the treatment of hematologic malignancies with successful results particularly with somewhat better results in hematological cancer in comparison to solid tumors. The AML is generally fatal, therapy-resistant, and sometimes refractory disease with a disappointing low survival rate and weak prognosis. The 5-year survival rate for AML is only about 30%. However, the survival rate seems to be age-dependent. Novel CAR T cell therapy is a light at the end of the tunnel. The CD19 is an important target antigen in AML and lymphoma and the CAR T cells are engineered to target the CD19. In addition, a lot of research goes on the discovery of novel target antigens with therapeutic efficacy and utilizable for generating CAR T cells against various types of cancers. In recent years, many pieces of research on screening and identification of novel AML antigen targets with the goal of generation of effective anti-cancer CAR T cells have led to new therapies with strong cytotoxicity against cancerous cells and impressive clinical outcomes. Also, more recently, an improved version of CAR T cells which were called modified or smartly reprogrammed CAR T cells has been designed with less unwelcome effects, less toxicity against normal cells, more safety, more specificity, longer persistence, and proliferation capability. The purpose of this review is to discuss and explain the most recent advances in CAR T cell-based therapies targeting AML antigens and review the results of preclinical and clinical trials. Moreover, we will criticize the clinical challenges, side effects, and the different strategies for CAR T cell therapy.

© 2018 Elsevier B.V. Development of efficient biodegradable, environmentally responsive, biocompatible and non-toxic delivery system is needed for efficient gene delivery. As well known, properties of the vehicle are determined by the structure of carrier components. The aim of the current study was to estimate in vitro transfection efficacy of aliphatic di-, tri- and tetrapeptide-based cationic lipoplexes loaded with siRNA in function of a number of cationic groups using 2D (monolayer culture) and 3D (multicellular tumor spheroids) in vitro models. Physicochemical properties and cytotoxicity of the liposomes were found to be dependent upon a number of amino acid derivatives in an amphiphilic polar head. Uptake of liposomes loaded with nucleic acid (lipoplexes) and their localization in HEK293T cells was studied by confocal microscopy. The liposomes based on lipotripeptides had the highest transfection efficiency which was 20-fold higher than those fabricated from lipotetrapeptides.

© 2018 Bulletin of Siberian Medicine. All rights reserved. The aim of the investigation was to determine the characteristics of the immune response regulation for pulmonary tuberculosis (TB) and to analyze the role of regulatory T cells in the immunopathogenesis of TB with eosinophilia in the blood, depending on the clinical form of the disease and sensitivity of Micobacterium tuberculosis to anti-TB drugs. Materials and methods. 157 patients who were initially diagnosed with infiltrative and disseminated TB were examined. The material of the study was venous blood and culture of mononuclear leukocytes isolated from venous blood. The content of interleukin (IL) 4, IL-10 and transforming factor beta (TGFβ) in culture suspensions of mononuclear leukocytes in vitro and IL-5 in the blood was determined by enzyme-linked immunosorbent assay (ELISA) test. The expression of surface molecules CD4, CD20, CD25 and intracellular transcription factor Foxp3 by lymphocytes of the blood was evaluated by flow cytometry. The obtained results were analyzed by statistical methods. Results. It is shown that excessive generation of regulatory T cells in patients with TB is associated with eosinophilia of the blood and imbalance of immune response regulation mechanisms. In TB with eosinophilia, an increase in the number of Foxp3-positive regulatory T cells in the blood is combined with in vitro hypersecretion of anti-inflammatory cytokines TGFβ, IL-10, IL-4 and an increase in the content of CD20+ B lymphocytes and IL-5 in the blood. These changes are most pronounced in the disseminated form of TB in combination with drug resistance. Conclusion. Characteristics of immunoregulation at TB with blood eosinophilia are associated with activation of immunosuppression mechanisms and polarization of immune response towards Th2-dependent pathway.

© 2018 Ima-Press Publishing House. All right reserved. Objective: to analyze the levels of CD3+, CD3+CD4+, CD3+CD8+, and CD3-CD56+ T lymphocytes, FoxP3+ regulatory T cells (Treg), and CD19+ B lymphocytes in patients with early and advanced rheumatoid arthritis (RA). Subjects and methods. The investigation enrolled 45 patients previously untreated with methotrexate (MTX-naive) who had early RA and 15 patients who had advanced RA. Immunofluorescence staining and multicolor flow cytome-try assays were used to estimate the percentage and absolute (abs) counts of CD3+, CD3+CD4+, CD3+CD8+, CD3-CD16+CD56+, CD19+, Treg (FoxP3+CD25+; surface CD152+; intracellular CD152+; FoxP3+CD127; CD25+CD127-; FoxP3+ICOS+; FoxP3+CD154+; and FoxP3+CD274+. Results and discussion. The patients with early RA were found to have a lower percentage of FoxP3+CD25+ cells and lower percentages and abs counts of FoxP3+ ICOS+ cells, FoxP3+CD154+ cells, and FoxP3+ CD274+ T cells than healthy donors (p0.05 in all cases). The patients with advanced RA were also recorded to have a lower percentage of FoxP3+CD25+ cells and lower percentages and abs contents of FoxP3+ ICOS+ cells, FoxP3+CD154+ cells, and FoxP3+ CD274+ T cells (p0.05 in all cases). The patients with advanced RA compared to those with early RA had a higher content of CD4+ lymphocytes (50.7 [44.4; 53.1] and 45.0 [38.0; 49.2]) and lower percentages of CD25+CD127- T lymphocytes (5.0 [4.0; 5.7] and 6.5 [5.1; 7.9] respectively; p0.05 in all cases). Conclusion. Patients with RA (with the early or advanced stage of the disease) show a decrease in both the counts and functional activity of Treg. The patients with advanced RA compared with those with early RA showed an increase in CD4+ lymphocyte counts and a decrease in CD25+CD127- cell levels, which suggests that there are more pronounced impairments in Treg homeostasis in advanced RA.