The Macrophage Activator GcMAF-RF Enhances the Antitumor Effect of Karanahan Technology through Induction of M2-M1 Macrophage Reprogramming

Macrophages are the immune cells of high-immunological plasticity, which can exert both pro- and anti-inflammatory activity, as well as repolarize their phenotype to the opposite or neutral one. In this regard, M2 macrophages of the tumor-associated stroma (TAS) are a promising therapeutic target in treating malignant neoplasms. Using FACS assay, we have estimated the CD11b+/Ly-6G+/Ly-6C+ fraction of macrophages from the peritoneum and TAS in intact healthy mice and those with developed Lewis carcinoma, both untreated and treated according to Karanahan technology in combination with group-specific macrophage activator (GcMAF-RF). As well, the pattern of pro- and anti-inflammatory cytokines mRNA expression in different groups of experimental and tumor-bearing animals was assessed. It was found that: (i) exposure of intact mice to GcMAF-RF results in the increased number of CD11b+/Ly-6C+ peritoneal macrophages and, at the same time, the expression pattern of cytokines in peritoneal macrophages switches from that characteristic of the mixed M1/M2 phenotype to that characteristic of the neutral M0 one; (ii) combination of Karanahan technology and GcMAF-RF treatment results in M0/M1 repolarization of TAS macrophages; (iii) in tumor-bearing mice, the response of peritoneal macrophages to such a treatment is associated with the induction of anti-inflammatory reaction, which is opposite to that in TAS macrophages.

Intranasal immunotherapy with M2 macrophage soluble factors in post-COVID hyposmia: A pilot study

Olfactory dysfunction is an early marker of COVID-19 infection. However, individuals may develop chronic olfactory impairment for more than six months in 1-10 % of cases. The study's objective is to evaluate the efficacy and safety of intranasal immunotherapy using bioactive substances produced by M2 macrophages for the treatment of people with long-term post-COVID-19 hyposmia. Seven individuals with long-term persistent hyposmia (7 to 24 months), associated with PCR-confirmed coronavirus infection were evaluated for olfactory function at baseline, one, and six to twelve months after therapy. The intranasal inhalation of M2 macrophage conditioned medum (one time per day for 28-30 days) was well tolerated. Furthermore, olfactometry demonstrated that the patients restored their capacity to perceive (Kruskal-Wallis H test 14.123, p = 0.0009) and recognize odours (H = 11.674, p = 0.0029). In addition, the subjective evaluation of smell significantly improved (H = 11.935, p = 0.0026). At the 6- to 12-month follow-up, the majority of patients (5/7) reported extremely high levels of satisfaction with the outcomes, and the remaining two patients also felt generally positive about the therapy's success. Overall, our study showed that the use of intranasal inhalations as a method of delivering bioactive factors and the conditioned medium of M2 macrophages as a therapeutic agent are both safe, well tolerated and, according to preliminary data, clinically effective in the treatment of patients with long-term post-COVID-19 hyposmia.

The Molecular Aspects of Functional Activity of Macrophage-Activating Factor GcMAF

Group-specific component macrophage-activating factor (GcMAF) is the vitamin D3-binding protein (DBP) deglycosylated at Thr420. The protein is believed to exhibit a wide range of therapeutic properties associated with the activation of macrophagal immunity. An original method for GcMAF production, DBP conversion to GcMAF, and the analysis of the activating potency of GcMAF was developed in this study. Data unveiling the molecular causes of macrophage activation were obtained. GcMAF was found to interact with three CLEC10A derivatives having molecular weights of 29 kDa, 63 kDa, and 65 kDa. GcMAF interacts with high-molecular-weight derivatives via Ca2+-dependent receptor engagement. Binding to the 65 kDa or 63 kDa derivative determines the pro- and anti-inflammatory direction of cytokine mRNA expression: 65 kDa-pro-inflammatory (TNF-α, IL-1β) and 63 kDa-anti-inflammatory (TGF-β, IL-10). No Ca2+ ions are required for the interaction with the canonical 29 kDa CLEC10A. Both forms, DBP protein and GcMAF, bind to the 29 kDa CLEC10A. This interaction is characterized by the stochastic mRNA synthesis of the analyzed cytokines. Ex vivo experiments have demonstrated that when there is an excess of GcMAF ligand, CLEC10A forms aggregate, and the mRNA synthesis of analyzed cytokines is inhibited. A schematic diagram of the presumable mechanism of interaction between the CLEC10A derivatives and GcMAF is provided. The principles and elements of standardizing the GcMAF preparation are elaborated.

Angiogenin as a Possible Mediator of Macrophage-Mediated Regulation of Fibroblast Functions

We studied angiogenin production by human macrophages and evaluated the role of this factor in the macrophage-mediated regulation of fibroblasts. All macrophage subtypes, and especially the efferocytosis-polarized macrophages, M2(LS), actively produced angiogenin. Exogenous recombinant angiogenin dose-dependently enhanced the proliferation and differentiation of dermal fibroblasts. The addition of the angiogenin inhibitor to fibroblasts cultures suppressed the stimulating effect of exogenous angiogenin or M2(LS) conditioned media. These findings indicate the involvement of angiogenin in the macrophage-mediated paracrine regulation of skin fibroblasts.

Impact of Double-Stranded RNA Internalization on Hematopoietic Progenitors and Krebs-2 Cells and Mechanism

It is well-established that double-stranded RNA (dsRNA) exhibits noticeable radioprotective and radiotherapeutic effects. The experiments conducted in this study directly demonstrated that dsRNA was delivered into the cell in its native form and that it induced hematopoietic progenitor proliferation. The 68 bp synthetic dsRNA labeled with 6-carboxyfluorescein (FAM) was internalized into mouse hematopoietic progenitors, c-Kit+ (a marker of long-term hematopoietic stem cells) cells and CD34+ (a marker of short-term hematopoietic stem cells and multipotent progenitors) cells. Treating bone marrow cells with dsRNA stimulated the growth of colonies, mainly cells of the granulocyte-macrophage lineage. A total of 0.8% of Krebs-2 cells internalized FAM-dsRNA and were simultaneously CD34+ cells. dsRNA in its native state was delivered into the cell, where it was present without any signs of processing. dsRNA binding to a cell was independent of cell charge. dsRNA internalization was related to the receptor-mediated process that requires energy from ATP. Synthetic dsRNA did not degrade in the bloodstream for at least 2 h. Hematopoietic precursors that had captured dsRNA reinfused into the bloodstream and populated the bone marrow and spleen. This study, for the first time, directly proved that synthetic dsRNA is internalized into a eukaryotic cell via a natural mechanism.

Comparative Efficacy of the Stromal-Vascular Fraction Cells of Lipoaspirate and Hyaluronic Acid in the Treatment of Gonarthrosis: Results of an Interim Analysis

The use of cell technologies, in particular the stromal-vascular fraction of adipose tissue, is a new direction in the treatment of osteoarthritis of the weight-bearing joints. Stromal-vascular fraction cells have anti-inflammatory and immunomodulatory effects and are able to differentiate into connective tissue cells, including cartilage, tendons, and ligaments. Our clinical study showed the safety and good tolerability of intra-articular administration of autologous stromal-vascular fraction cells in 16 patients with severe manifestations of osteoarthritis. Single administration of stromal-vascular fraction cells led to more pronounced and stable (up to 12 months) clinical improvement in the main symptoms of the disease, including pain and functional activity of the affected joints, in comparison with intra-articular injection of hyaluronic acid (10 patients of the comparison group).

The new general biological property of stem-like tumor cells Part I. Peculiarities of the process of the double-stranded DNA fragments internalization into stem-like tumor cells

Stem-like tumor cells of ascites carcinoma Krebs-2 and Epstein-Barr virus–induced B-lymphoma were shown to possess the innate capability of binding and internalizing the TAMRA-labeled double-stranded DNA (dsDNA) probe. The process of binding and internalizing is rather complicated and composed of the following successive stages: 1) initiating electrostatic interaction and contact of a negatively charged dsDNA molecule with a positively charged molecule(s) on the surface of a stem-like tumor cell; 2) binding of the dsDNA probe to a tumor stem cell surface protein(s) via the formation of a strong chemical/molecular bond; and 3) the very internalization of dsDNA into the cell. Binding of DNA to cell surface proteins is determined by the presence of heparin/polyanion-binding sites within the protein structure, which can be competitively blocked by heparin and/or dextran sulfate, wherein heparin blocks only the binding, while dextran sulfate abrogates both binding and internalization. The abrogation of internalization by dextran sulfate implies the role of scavenger receptors in this process. Cells were shown to uptake DNA in amounts constituting ∼0.008% of the haploid genome. Inhibitors of caveolae-dependent internalization abrogate the DNA uptake in Krebs-2 cells, and inhibitors of the clathrin/caveolar mechanism block the internalization in B-lymphoma cells. In the present report, it is shown for the first time that in contrast to the majority of committed tumor cells, stem-like tumor cells of Krebs-2 and B-lymphoma carry a general positive charge on their surface.

Karanahan: A Potential New Treatment Option for Human Breast Cancer and Its Validation in a Clinical Setting

Introduction:

Karanahan, a cancer treatment technology aimed at eradicating tumor-initiating stem cells, has already proven effective in 7 tumor models. Karanahan comprises the following procedures: (1) collecting surgical specimens, (2) determining the duration of the DNA repair process in tumor cells exposed to a cross-linking cytostatic agent, and (3) determining the time point, when cells, including tumor-initiating stem cells, are synchronized in the certain phase of the cell cycle after triple exposure to the cytostatic, becoming vulnerable for the terminal treatment, which is supposed to completely eliminate the rest of survived tumor-initiating stem cells. Determining these basic tumor properties allows to design the schedule for the administration of a cross-linking cytostatic and a complex composite DNA preparation. Being conducted in accordance with the schedule designed, Karanahan results in the large-scale apoptosis of tumor cells with elimination of tumor-initiating stem cells.

Methods:

Breast tumor specimens were obtained from patients, and basic tumor properties essential for conducting Karanahan therapy were determined.

Results:

We report the first use of Karanahan in patients diagnosed with breast cancer. Technical details of handling surgical specimens for determining the essential Karanahan parameters (tumor volume, cell number, cell proliferation status, etc) have been worked out. The terminally ill patient, who was undergoing palliative treatment and whose tumor specimen matched the required criteria, received a complete course of Karanahan.

Conclusions:

The results of the treatment conducted indicate that Karanahan technology has a therapeutic potency and can be used as a breast cancer treatment option.

Theoretical premises of a "three in one" therapeutic approach to treat immunogenic and nonimmunogenic cancers: a narrative review

Objective

We describe experimental and theoretical premises of a powerful cancer therapy based on the combination of three approaches. These include (I) in situ vaccination (intratumoral injections of CpG oligonucleotides and anti-OX40 antibody); (II) chronometric or metronomic low-dose cyclophosphamide (CMLD CP)-based chemotherapy; (III) cancer stem cell-eradicating therapy referred to as Karanahan (from the Sanskrit kāraṇa [“source”] + han [“to kill”]).

Background

In murine models, the first two approaches are particularly potent in targeting immunogenic tumors for destruction. In situ vaccination activates a fully fledged anticancer immune response via an intricate network of ligand–receptor–cytokine interactions. CMLD CP-based chemotherapy primarily targets the suppressive tumor microenvironment and activates tumor-infiltrating effectors. In contrast, Karanahan technology, being aimed at replicative machinery of tumor cells (both stem-like and committed), does not depend on tumor immunogenicity. With this technology, mice engrafted with ascites and/or solid tumors can be successfully cured. There is a significant degree of mechanistic and therapeutic overlap between these three approaches. For instance, the similarities shared between in situ vaccination and Karanahan technology include the therapeutic procedure, the cell target [antigen-presenting cells (APC) and dendritic cells (DC)], and the use of DNA-based preparations (CpG and DNAmix). Features shared between CMLD CP-based chemotherapy and Karanahan technology are the timing and the dose of the cytostatic drug administration, which lead to tumor regression.

Methods

The following keywords were used to search PubMed for the latest research reporting successful eradication of transplantable cancers in animal models that relied on approaches distinct from those used in the Karanahan technology: eradication of malignancy, cure cancer, complete tumor regression, permanently eradicating advanced mouse tumor, metronomic chemotherapy, in situ vaccination, immunotherapy, and others.

Conclusion

We hypothesize, therefore, that very potent anticancer activity can be achieved once these three therapeutic modalities are combined into a single approach. This multimodal approach is theoretically curative for any type of cancer that depends on the presence of tumor-inducing cancer stem cells, provided that the active therapeutic components are efficiently delivered into the tumor and the specific biological features of a given patient’s tumor are properly addressed. We expect this multimodal approach to be primarily applicable to late-stage or terminal cancer patients who have exhausted all treatment options as well as patients with inoperable tumors.

Effect of M2 Macrophage-Derived Soluble Factors on Behavioral Patterns and Cytokine Production in Various Brain Structures in Depression-Like Mice

We studied the effect of soluble factors derived from human macrophages polarized to M2 phenotype under conditions of serum deprivation (M2-SF) on behavioral pattern and cytokine production in various brain structures in mice with modeled stress-induced depression. Intranasal administration of M2-SF for 7 days led to stimulation of locomotor and exploratory activities and a decrease in emotional reactivity in the open-field test as well as reduction in depression-like behavior in Porsolt forced swimming test and a decrease in anxiety and anhedonia. Correction of depression-like behavior was accompanied by down-regulation of proinflammatory cytokines (IL-1β, IL-6, TNFα, and IFNγ) in pathogenetically important brain structures (striatum, hippocampus, and frontal cortex). These data indicate that the antidepressant potential of M2 type macrophages can be mediated by the anti-inflammatory effects of M2-SF.

Antitumor efficacy of multi-target <i>in situ</i> vaccinations with CpG oligodeoxynucleotides, anti-OX40, anti-PD1 antibodies, and aptamers

To overcome immune tolerance to cancer, the immune system needs to be exposed to a multi-target action intervention. Here, we investigated the activating effect of CpG oligodeoxynucleotides (ODNs), mesyl phosphoramidate CpG ODNs, anti-OX40 antibodies, and OX40 RNA aptamers on major populations of immunocompetent cells ex vivo. Comparative analysis of the antitumor effects of in situ vaccination with CpG ODNs and anti-OX40 antibodies, as well as several other combinations, such as mesyl phosphoramidate CpG ODNs and OX40 RNA aptamers, was conducted. Antibodies against programmed death 1 (PD1) checkpoint inhibitors or their corresponding PD1 DNA aptamers were also added to vaccination regimens for analytical purposes. Four scenarios were considered: a weakly immunogenic Krebs-2 carcinoma grafted in CBA mice; a moderately immunogenic Lewis carcinoma grafted in C57Black/6 mice; and an immunogenic A20 B cell lymphoma or an Ehrlich carcinoma grafted in BALB/c mice. Adding anti-PD1 antibodies (CpG+αOX40+αPD1) to in situ vaccinations boosts the antitumor effect. When to be used instead of antibodies, aptamers also possess antitumor activity, although this effect was less pronounced. The strongest effect across all the tumors was observed in highly immunogenic A20 B cell lymphoma and Ehrlich carcinoma.

Efficacy of the new therapeutic approach in curing malignant neoplasms on the model of human glioblastoma

OBJECTIVE

Glioma is a highly invasive tumor, frequently disposed in essential areas of the brain, which makes its surgical excision extremely difficult; meanwhile adjuvant therapy remains quite ineffective.

METHODS

In the current report, a new therapeutic approach in curing malignant neoplasms has been performed on the U87 human glioblastoma model. This approach, termed "Karanahan", is aimed at the eradication of cancer stem cells (CSCs), which were recently shown to be capable of internalizing fragments of extracellular double-stranded DNA. After being internalized, these fragments interfere in the process of repairing interstrand cross-links caused by exposure to appropriate cytostatics, and such an interference results either in elimination of CSCs or in the loss of their tumorigenic potency. Implementation of the approach requires a scheduled administration of cytostatic and complex composite double-stranded DNA preparation.

RESULTS

U87 cells treated in vitro in accordance with the Karanahan approach completely lost their tumorigenicity and produced no grafts upon intracerebral transplantation into immunodeficient mice. In SCID mice with developed subcutaneous grafts, the treatment resulted in reliable slowing down of tumor growth rate (P < 0.05). In the experiment with intracerebral transplantation of U87 cells followed by surgical excision of the developed graft and subsequent therapeutic treatment, the Karanahan approach was shown to reliably slow down the tumor growth rate and increase the median survival of the mice twofold relative to the control.

CONCLUSIONS

The effectiveness of the Karanahan approach has been demonstrated both in vitro and in vivo in treating developed subcutaneous grafts as well as orthotopic grafts after surgical excision of the tumor.

Experimental Comparison of the In Vivo Efficacy of Two Novel Anticancer Therapies

BACKGROUND/AIM

We compared the therapeutic efficacy of two recently developed experimental anticancer technologies: 1) in situ vaccination based on local immunotherapy with CpG oligonucleotides and anti-OX40 antibodies to activate antitumor immune response and 2) "Karanahan" technology [from the Sanskrit kāraṇa ('source') + han ('to kill')] based on the combined injection of cyclophosphamide and double-stranded DNA to eradicate cancer stem cells.

MATERIALS AND METHODS

The anticancer approaches were compared on three types of mouse malignant tumors with different grades of immunogenicity: weakly immunogenic carcinoma Krebs-2, moderately immunogenic Lewis carcinoma, and highly immunogenic A20 В-cellular lymphoma.

RESULTS

Our results indicated that in situ vaccination was the most effective against the highly immunogenic tumor А20. In addition, "Karanahan" demonstrated high efficiency in all types of tumors, regardless of their immunogenicity or size.

CONCLUSION

"Karanahan" therapy showed higher efficacy relative to in situ vaccination with CpG oligonucleotides and anti-OX40 antibodies.

Epitope mapping of novel monoclonal antibodies to human angiotensin I-converting enzyme

Angiotensin I-converting enzyme (ACE, CD143) plays a crucial role in blood pressure regulation, vascular remodeling, and immunity. A wide spectrum of mAbs to different epitopes on the N and C domains of human ACE have been generated and used to study different aspects of ACE biology, including establishing a novel approach-conformational fingerprinting. Here we characterized a novel set of 14 mAbs, developed against human seminal fluid ACE. The epitopes for these novel mAbs were defined using recombinant ACE constructs with truncated N and C domains, species cross-reactivity, ACE mutagenesis, and competition with the previously mapped anti-ACE mAbs. Nine mAbs recognized regions on the N domain, and 5 mAbs-on the C domain of ACE. The epitopes for most of these novel mAbs partially overlap with epitopes mapped onto ACE by the previously generated mAbs, whereas mAb 8H1 recognized yet unmapped region on the C domain where three ACE mutations associated with Alzheimer's disease are localized and is a marker for ACE mutation T877M. mAb 2H4 could be considered as a specific marker for ACE in dendritic cells. This novel set of mAbs can identify even subtle changes in human ACE conformation caused by tissue-specific glycosylation of ACE or mutations, and can detect human somatic and testicular ACE in biological fluids and tissues. Furthermore, the high reactivity of these novel mAbs provides an opportunity to study changes in the pattern of ACE expression or glycosylation in different tissues, cells, and diseases, such as sarcoidosis and Alzheimer's disease.

Effects of Recombinant Angiogenin on Collagen Fiber Formation and Angiogenesis in the Dermis of Wistar Rats

Purpose

The purpose of this study was to assess the capability of recombinant angiogenin isolated from Pichia pastoris yeasts to stimulate regenerative processes in the dermis of experimental animals.

Patients and Methods

Wistar rats were administered with recombinant angiogenin intracutaneously. Morphological examination of the skin and the assessment of the proliferative activity of the epidermal cells were carried out. Additionally, cytokine production by human whole blood cells exposed to angiogenin was analyzed ex vivo.

Results

Administration of angiogenin stimulates collagen fiber formation and angiogenesis. This stimulation is tightly associated with an increase in the number of fibroblasts, an increased numerical density of dermal blood vessels and an increased density of collagen fibers; also, it activates the proliferation of basal cells. Angiogenin induces the production of MCP, IL-8, IL-6, IL-1β, TNF-α, IL-10, TGF-β, and VEGF by blood cells.

Conclusion

The results obtained indicate a broad spectrum of actions of recombinant angiogenin during regenerative processes in the basal layer of the dermis.

Phosphate-modif ied CpG oligonucleotides induce in vitro maturation of human myeloid dendritic cells

Myeloid dendritic cells (DCs) play an important role in the immune response; therefore, the search for compounds that can effectively activate DCs is a needful goal. This study was aimed to investigate the effect of synthetic CpG oligodeoxynucleotides (CpG-ODN) on the maturation and allostimulatory activity of myeloid DCs in comparison with other PAMP and DAMP molecules. For the research, we synthesized known CpG-ODN class C (SD-101 and D-SL03) containing thiophosphate internucleotide groups, and their original phosphate-modified analogues (SD-101M and D- SL03M) with mesylphosphoramide internucleotide groups (M = μ-modification). The effects of CpG-ODN and other activators were evaluated on DCs generated from blood monocytes in the presence of GM-CSF and IFN-α (IFN-DC) or IL-4 (IL4-DC). Evaluation of the intracellular TLR-9 expression showed that both types of DCs (IFN-DC and IL4-DC) contained on average 52 and 80 % of TLR-9-positive cells, respectively. The CpG-ODNs studied enhanced the allostimulatory activity of IFN-DCs, and the effect of μ-modified CpG-ODNs was higher than that of CpG-ODNs with thiophosphate groups. The stimulating effect of CpG-ODN at a dose of 1.0 μg/ml was comparable (for D-SL03, D-SL03M, SD-101) with or exceeded (for SD-101M) the effect of LPS at a dose of 10 μg/ml. At the same time, IFN-DCs were characterized by greater sensitivity to the action of CpG-ODNs than IL4-DCs. The enhancement of DC allostimulatory activity in the presence of CpG-ODNs was associated with the induction of final DC maturation, which was confirmed by a significant decrease in the number of CD14+DC, an increase in mature CD83+DC and a trend towards an increase in CD86+DC. Interestingly, the characteristic ability of LPS to enhance the expression of the co-stimulatory molecule OX40L on DCs was revealed only for the μ-analogue SD-101M. In addition, CpG-ODNs (SD-101 and SD-101M) had a stimulatory effect on IFN-γ production comparable to the action of LPS. The data obtained indicate a stimulating effect of CpG-ODN on the maturation and allostimulatory activity of human myeloid DCs, which is more pronounced for μ-modified analogs.

Quantitative and functional characteristics of circulating and bone marrow PD-1- and TIM-3-positive T cells in treated multiple myeloma patients

The aim of the present work was to evaluate counts and functional properties of PD-1⁺ and TIM-3⁺ T cells in peripheral blood (PB) and bone marrow (BM) of multiple myeloma (MM) patients following the induction therapy. Sixty patients were enrolled in the study, CD4⁺ and CD8⁺ T cells expressing PD-1 and TIM-3, intracellular production of IFNγ and intracellular expression of Granzyme B were assessed. Relative counts of the majority of circulating PD-1⁺, TIM-3⁺ and PD-1⁺TIM-3⁺ T cells were higher in MM patients with disease progression compared with individuals in remission. Frequencies of almost all evaluated PD-1⁺ and TIM-3⁺ T cell subsets were higher in BM samples compared with PB; circulating CD4⁺PD-1⁺, CD8⁺PD-1⁺, CD8⁺TIM-3⁺, CD8⁺PD-1⁺TIM-3⁺ T cells positively correlated with the same BM subsets. Circulating CD4⁺ T cells, expressing PD-1 and TIM-3 (including co-expressing subset), as well as CD8⁺PD-1⁺TIM-3⁺ T cells, and BM CD8⁺PD-1⁺ T cells correlated with serum B2-M levels. Sufficient frequencies of GrB⁺ and IFNγ⁺ subsets in PD-1-expressing T cells indicated their retained functional properties. TIM-3-expressing T cells and double positive PD-1⁺TIM-3⁺ populations showed diminished cytotoxic and cytokine-producing ability and therefore might be attributed to the exhausted compartment. To identify T cell exhaustion, it is necessary to evaluate T cells co-expressing PD-1, TIM-3 and other inhibitory signal molecules and to study their functional properties. Sustained functionality of PD-1-positive T cells may explain low efficacy and frequent immune-mediated adverse events during anti-PD-1 therapy in MM.

Approbation of the Cancer Treatment Approach Based on the Eradication of TAMRA+ Cancer Stem Cells in a Model of Murine Cyclophosphamide Resistant Lymphosarcoma

BACKGROUND/AIM

We previously have described the "3+1" tumors cure approach consisting of individual time schedule of cyclophosphamide and dsDNA preparation administrations. The aim of the study was to adapt the "3+1" approach based on eradication of cancer stem cells to the model of murine ascitic cyclophosphamide-resistant lymphosarcoma (RLS).

MATERIALS AND METHODS

Adaptation of the "3+1" approach includes the identification of the timing to disrupt the tumorigenic potential of a certain tumor.

RESULTS

The proposed therapeutic scheme allowed complete reduction of primary RLS ascites in experimental animals. However, reduction of primary ascites due to the complementary action of cyclophosphamide and dsDNA was inevitably followed by the development of a secondary one, most likely arising from a solid carcinomatous formation in the peritoneal wall.

CONCLUSION

The "3+1" approach resulted in the elimination of cancer stem cells, and, as a consequence, in the complete reduction of RLS ascites.

Autologous and Pooled Tumor Lysates in Combined Immunotherapy of Patients with Glioblastoma

Although major progress has been made in the standard treatment for glioblastomas, encompassing the maximal surgical resection, chemotherapy and radiation therapy, it is possible to increase survival rates significantly only in a few patients. Therefore, it is necessary to explore new therapeutic modalities, one of which is immunotherapy.

The aim of the study was to evaluate the efficacy of the combined use of autologous and pooled tumor lysates in comprehensive treatment of patients with glioblastoma.

Increased circulating CD3+ T cells are associated with early relapse following autologous hematopoietic stem cell transplantation in patients with classical Hodgkin lymphoma

Non-malignant host immune cells are the main substrate in classical Hodgkin lymphoma (HL) microenvironment. Reconstitution of lymphocyte populations following the high-dose chemotherapy (HDC) with autologous hematopoietic stem cell transplantation (auto-HSCT) can support tumor growth in HL patients. We investigated recovery dynamics of circulating CD3⁺, CD4⁺, CD8⁺, CD16⁺/CD56⁺, CD19⁺, CD4⁺FOXP3⁺ lymphocytes following auto-HSCT in 79 HL patients and assessed relationship between these populations and the development of early relapse. Studied populations were not statistically significant between patients with high or standard/intermediate risk of relapse. CD3⁺ T cells at the time of engraftment were increased in patients with the early relapse of HL compared to non-relapsed patients (P_U = 0.0028). Area under the curve was 0.76 (р = .0037). In logistic regression models, CD3⁺ T cell count was associated with early relapse/progression as a trend. These findings elucidate several interactions between early systemic T cell recovery and tumor progression following HDC with auto-HSCT.

Allostimulatory activity as a criterion of the functional phenotype of human macrophages

The functional phenotype of macrophages (Mφ) is determined by both differentiation factors and polarization stimuli. In mouse Mφ could be easily divided into the distinct Mφ subtypes. However, the identification of human M1 and M2 cells is much more difficult due to the lack of M1- or M2-specific markers. We assumed that the Mφ capacity to induce T cell proliferation in mixed leukocyte culture, or allostimulatory activity, may be a marker of Mφ functional phenotype. We compared the allostimulatory activity of Mφ differentiated with GM-CSF or M-CSF and polarized into M1, M2a, M2c subtypes using appropriate stimuli. GM-CSF-differentiated M1 Mφ showed pronounced allostimulatory activity whereas the polarization into M2a and M2c of GM-CSF-differentiated Mφ was associated with decreased allostimulatory activity. M-CSF-differentiated M1 Mφ demonstrated the moderate increasing of allostimulatory activity but its level has never reached that of GM-CSF-activated M1. The level of allostimulatory activity of M2a and M2c M-CSF-induced Mφ was comparable to that of GM-CSF-induced M2a and M2c Mφ. Thus, low allostimulatory activity is a common property of human M2a and M2c macrophages regardless of the differentiating factor and a polarizing stimulus and can be used to distinguish between M1 and M2 phenotypes.

Identification of the xenograft and its ascendant sphere-forming cell line as belonging to EBV-induced lymphoma, and characterization of the status of sphere-forming cells

Background

We have characterized the human cell line arised from the Epstein–Barr virus (EBV) positive multiple myeloma aspirate subjected to the long-term cultivation. This cell line has acquired the ability to form free-floating spheres and to produce a xenograft upon transplantation into NOD/SCID mice.

Methods

Cells from both in vitro culture and developed xenografts were investigated with a number of analytical approaches, including pathomorphological analysis, FISH analysis, and analysis of the surface antigens and of the VDJ locus rearrangement.

Results

The obtained results, as well as the confirmed presence of EBV, testify that both biological systems are derived from B-cells, which, in turn, is a progeny of the EBV-transformed B-cellular clone that supplanted the primordial multiple myeloma cells. Next we assessed whether cells that (i) were constantly present in vitro in the investigated cell line, (ii) were among the sphere-forming cells, and (iii) were capable of internalizing a fluorescent TAMRA-labeled DNA probe (TAMRA+ cells) belonged to one of the three types of undifferentiated bone marrow cells of a multiple myeloma patient: CD34+ hematopoietic stem cells, CD90+ mesenchymal stem cells, and clonotypic multiple myeloma cell.

Conclusion

TAMRA+ cells were shown to constitute the fourth independent subpopulation of undifferentiated bone marrow cells of the multiple myeloma patient. We have demonstrated the formation of ectopic contacts between TAMRA+ cells and cells of other types in culture, in particular with CD90+ mesenchymal stem cells, followed by the transfer of some TAMRA+ cell material into the contacted cell.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0842-x) contains supplementary material, which is available to authorized users.

Novel Cancer Stem Marker and Its Applicability for Grading Primary Human Gliomas

Poorly differentiated cell populations including tumor-initiating stem cells have been demonstrated to display a unique ability to natively internalize fragmented double-stranded DNA. Using this feature as a marker, we show that 0.1% to 6% of human glioblastoma cells from the bioptates can effectively internalize a fluorescently labeled DNA probe. Of these, using samples from 3 patients, 66% to 100% cells are also positive for CD133, a well-established surface marker of tumor-initiating glioma stem cells. Using the samples from primary malignant brain lesions (33 patients), we demonstrate that tumor grading significantly correlates ( R = .71) with the percentage of DNA-internalizing cells. No such correlation is observed for relapse samples (18 patients).

Cancer Stem Cells: Emergent Nature of Tumor Emergency

A functional analysis of 167 genes overexpressed in Krebs-2 tumor initiating cells was performed. In the first part of the study, the genes were analyzed for their belonging to one or more of the three groups, which represent the three major phenotypic manifestation of malignancy of cancer cells, namely (1) proliferative self-sufficiency, (2) invasive growth and metastasis, and (3) multiple drug resistance. 96 genes out of 167 were identified as possible contributors to at least one of these fundamental properties. It was also found that substantial part of these genes are also known as genes responsible for formation and/or maintenance of the stemness of normal pluri-/multipotent stem cells. These results suggest that the malignancy is simply the ability to maintain the stem cell specific genes expression profile, and, as a consequence, the stemness itself regardless of the controlling effect of stem niches. In the second part of the study, three stress factors combined into the single concept of "generalized cellular stress," which are assumed to activate the expression of these genes, were defined. In addition, possible mechanisms for such activation were identified. The data obtained suggest the existence of a mechanism for the de novo formation of a pluripotent/stem phenotype in the subpopulation of "committed" tumor cells.

Efficacy of a new cancer treatment strategy based on eradication of tumor-initiating stem cells in a mouse model of Krebs-2 solid adenocarcinoma

Krebs-2 solid carcinoma was cured using a new “3+1” strategy for eradication of Krebs-2 tumor-initiating stem cells. This strategy was based on synchronization of these cells in a treatment-sensitive phase of the cell cycle. The synchronization mechanism, subsequent destruction of Krebs-2 tumor-initiating stem cells, and cure of mice from a solid graft were found to depend on the temporal profile of the interstrand cross-link repair cycle. Also, the temporal profile of the Krebs-2 interstrand repair cycle was found to have a pronounced seasonal cyclicity at the place of experiments (Novosibirsk, Russia). As a result, the therapeutic effect that is based on application of the described strategy, originally developed for the “winter repair cycle” (November−April), is completely eliminated in the summer period (June−September). We conclude that оne of the possible and the likeliest reasons for our failure to observe the therapeutic effects was the seasonal cyclicity in the duration of the interstrand repair cycle, the parameter that is central to our strategy.

Increased circulating CD4+FOXP3+ T cells associate with early relapse following autologous hematopoietic stem cell transplantation in multiple myeloma patients

We investigated dynamics of CD4⁺FOXP3⁺ T cell recovery following the high-dose chemotherapy (HDC) with autologous hematopoietic stem cell transplantation (auto-HSCT) in multiple myeloma (MM) patients. Circulating CD4⁺FOXP3⁺ T cells of 79 MM patients were evaluated using flow cytometry before HDC with auto-HSCT, at the day of engraftment, and following 6 and 12 months. Percentage of CD4⁺FOXP3⁺ T cells restored rapidly following auto-HSCT, became higher than pre-transplant level at the day of engraftment and then subsequently decreased for a year. CD4⁺FOXP3⁺ T cells at the time of engraftment were increased in patients with the relapse or progression of MM during 12 months following auto-HSCT (n=10) compared to non-relapsed patients (n=50): 6.7% (5.3-8.9%) vs 4.9% (2.8-6.6%); P_U = 0.026. Area under the curve was 0.72 (95% CI: 0.570-0.878; р=0.026). Circulating CD4⁺FOXP3⁺ T cell count was not associated with the percentage of myeloma plasma cells in a bone marrow but depended on its amount in autografts.

Conclusions

Relative count of CD4⁺FOXP3⁺ T cells restored rapidly following auto-HSCT (at the day of engraftment), became higher than pre-transplant level and then subsequently decreased for a year. Their excess at the time of engraftment is associated with early relapse.

Clinical Cell Therapy Guidelines for Neurorestoration (IANR/CANR 2017)

Cell therapy has been shown to be a key clinical therapeutic option for central nervous system diseases or damage. Standardization of clinical cell therapy procedures is an important task for professional associations devoted to cell therapy. The Chinese Branch of the International Association of Neurorestoratology (IANR) completed the first set of guidelines governing the clinical application of neurorestoration in 2011. The IANR and the Chinese Association of Neurorestoratology (CANR) collaborated to propose the current version "Clinical Cell Therapy Guidelines for Neurorestoration (IANR/CANR 2017)". The IANR council board members and CANR committee members approved this proposal on September 1, 2016, and recommend it to clinical practitioners of cellular therapy. These guidelines include items of cell type nomenclature, cell quality control, minimal suggested cell doses, patient-informed consent, indications for undergoing cell therapy, contraindications for undergoing cell therapy, documentation of procedure and therapy, safety evaluation, efficacy evaluation, policy of repeated treatments, do not charge patients for unproven therapies, basic principles of cell therapy, and publishing responsibility.

A strategy to eradicate well-developed Krebs-2 ascites in mice

We describe the strategy, which allows curing experimental mice engrafted with Krebs-2 ascites. The strategy is based on the facts that i) Krebs-2 tumor-initiating stem cells (TISCs) are naturally capable of internalizing fragments of extracellular double-stranded DNA (dsDNA); ii) upon delivery into TISCs, these dsDNA fragments interfere with the on-going DNA repair process so that TISCs either die or lose their tumorigenic potential. The following 3-step regimen of therapeutic procedures leading to eradication of Krebs-2 ascites is considered. Firstly, three timed injections of cyclophosphamide (CP) exactly matching the interstrand cross-link (ICL) repair phases that lead to synchronization of ascites cells in late S/G2/M. Secondly, additional treatment of ascites 18 hours post each CP injection (at NER/HR transition timepoint) with a composite dsDNA-based preparation interfering with the NER and HR repair pathways, so that tumorigenic properties of ascites cells are compromised. Thirdly, final treatment of mice with a combination of CP and dsDNA injections as ascites cells undergo apoptotic destruction, and the surviving TAMRA+ TISCs arrested in late S/G2/M phases massively enter into G1/S, when they regain sensitivity to CP+dsDNA treatment. Thus, this regimen assures that no viable cells, particularly Krebs-2 TISCs, remain.

CD4+ memory T cells retain surface expression of CD31 independently of thymic function in patients with lymphoproliferative disorders following autologous hematopoietic stem-cell transplantation

High-dose chemotherapy with autologous hematopoietic stem-cell transplantation (AHSCT) causes severe and long-lasting immunodeficiency in patients with lymphoproliferative disorders. The thymus begins to restore the T-cell repertoire approximately from the sixth month post-transplant. We assessed the dynamics of post-transplant recovery of CD4⁺CD45RA⁺CD31⁺ T cells, "recent thymic emigrants" (RTEs), and a poorly described subtype of CD4⁺CD45RA^-CD31⁺ T cells in 90 patients with lymphoproliferative disorders following high-dose chemotherapy with AHSCT. Relative and absolute counts of CD4⁺CD31⁺ naïve and memory T cells were evaluated before AHSCT, at the day of engraftment, and 6- and 12-month post-transplant. The pre-transplant count of CD4⁺CD45RA⁺CD31⁺ T cells was lower than in healthy controls, and did not reach donors' values during the 12-month period. The pre-transplant number of CD4⁺CD45RA^-CD31⁺ T cells was higher than in healthy controls and was restored rapidly following AHSCT. Post-transplant mediastinal radiotherapy reduced counts of RTEs and elongated recovery period. Non-thymic tissue irradiation did not reduce this subset. The obtained data indicate that homeostatic proliferation may decrease the significance of CD31 expression on CD4⁺CD45RA⁺ T cells as a marker of RTEs, and suggest that evaluation of RTEs recovery by flow cytometry requires an accurate gating strategy to exclude CD31⁺ memory T cells.

Gene expression profiling of tumor-initiating stem cells from mouse Krebs-2 carcinoma using a novel marker of poorly differentiated cells

Using the ability of poorly differentiated cells to natively internalize fragments of extracellular double-stranded DNA as a marker, we isolated a tumorigenic subpopulation present in Krebs-2 ascites that demonstrated the features of tumor-inducing cancer stem cells. Having combined TAMRA-labeled DNA probe and the power of RNA-seq technology, we identified a set of 168 genes specifically expressed in TAMRA-positive cells (tumor-initiating stem cells), these genes remaining silent in TAMRA-negative cancer cells. TAMRA+ cells displayed gene expression signatures characteristic of both stem cells and cancer cells. The observed expression differences between TAMRA+ and TAMRA- cells were validated by Real Time PCR. The results obtained corroborated the biological data that TAMRA+ murine Krebs-2 tumor cells are tumor-initiating stem cells. The approach developed can be applied to profile any poorly differentiated cell types that are capable of immanent internalization of double-stranded DNA.

Intraocular cytokines in retinal vein occlusion and its relation to the efficiency of anti-vascular endothelial growth factor therapy

Purpose:

To analyze the change in the concentration of intraocular cytokines (ICs) in patients with retinal vein occlusion (RVO) before and after intravitreal ranibizumab therapy (IVR), and to find the correlations of IC with clinical activity of RVO and efficiency of treatment.

Materials and Methods:

Forty-four patients aged 46–79 years old (mean age: 60.7 ± 7.5 years old) with RVO and macular edema (18 patients – with central RVO, 26 – with branch RVO) treated with IVR were included into the study. The concentrations of 27 cytokines were simultaneously measured in aqueous humor by flow fluorometry using Bio-Plex Pro Human Cytokine Panel, 27-Plex (Bio-Rad Laboratories, USA) at baseline and after the first IVR. Control group consisted of 20 age-matched patients.

Results:

The levels of 11 cytokines (vascular endothelial growth factor [VEGF], receptor antagonist interleukin-1, interleukin-6 [IL-6], IL-8, IL-9, IL-10, IL-12r70, IL-13, IL-15, monocyte chemotactic protein-1 [MCP-1], regulated on activation, normal T expressed and secreted) were significantly (P < 0.05) different compared to control and significantly (P < 0.05) changed after IVR both in central and branch RVO. The patients were divided into two groups: the first -“effective” and the second - “partially effective” therapy. The second group characterized by the higher concentrations of VEGF, IL-8, IL-10, IL-17, and MCP-1 at baseline compared to the first group.

Conclusion:

The patients with RVO were characterized by the increased levels of VEGF and other pro- and anti-inflammatory cytokines and chemokines. Aqueous concentration of cytokines were different in patients with central and branch RVO and significantly changed after IVR. Insufficient response to IVR was associated with activation of immune-inflammatory processes.

[Role of immunological factors in the development of myopic choroidal neovascularization]

AIM

To study the concentration of cytokines in the aqueous humor of the anterior chamber in patients with myopic choroidal neovascularization (mCNV) and to compare the results to their ophthalmic status.

MATERIAL AND METHODS

A total of 19 patients (19 eyes) with mCNV treated with intravitreal ranibizumab were included in the study. The control group consisted of 15 patients (15 eyes) with myopia who had cataract surgery. Age, sex, and refractive error distribution were similar to that in the study group. All patients underwent a detailed ophthalmic examination as well as immunological study of the aqueous humor for cytokines concentrations using flow fluorometry (Bio-Plex Pro Human Cytokine Panel, 27-Plex, Bio-Rad Laboratories, USA).

RESULTS

Significant differences in concentrations of 10 cytokines were found between the mCNV and study groups. Vascular endothelial growth factor (VEGF) level was twice as low in patients with mCNV as that in the controls (191.15±142.3 pg/ml and 320.06±170.05 pg/ml, respectively) (p<0.05). The other 9 cytokines were higher in mCNV, namely, platelet-derived growth factor (PDGF-BB), inflammatory and anti-inflammatory cytokines (IL-2, IL-15, IL-17А and IL-5, IL-13, respectively), tumor necrosis factor (TNFα), and chemokines (IL-8, RANTES). The degree of myopia as well as morphological and functional changes in the macular zone were shown to be in close correlation with cytokines involved in inflammation and VEGF. VEGF level appeared to be negatively related to axial eye length, refractive error, and three cytokines: IL-13, INF-γ, and RANTES. At the same time, numerous (6, 8 and more) close correlations were established between inflammatory and anti-inflammatory cytokines, chemokines, and growth factors.

CONCLUSION

Patients with mCNV have been found to have higher than usual levels of inflammatory and anti-inflammatory cytokines, chemokines, and growth factors as well as a significantly decreased VEGF concentration. Immunological status of these patients differs from that in other ocular neovascular diseases suggesting possible involvement of alternative pathogenetic mechanisms.

Five-year disease-free survival among stage II-IV breast cancer patients receiving FAC and AC chemotherapy in phase II clinical trials of Panagen

BACKGROUND

We report on the results of a phase II clinical trial of Panagen (tablet form of fragmented human DNA preparation) in breast cancer patients (placebo group n = 23, Panagen n = 57). Panagen was administered as an adjuvant leukoprotective agent in FAC and AC chemotherapy regimens. Pre-clinical studies clearly indicate that Panagen acts by activating dendritic cells and induces the development of adaptive anticancer immune response.

METHODS

We analyzed 5-year disease-free survival of patients recruited into the trial.

RESULTS

Five-year disease-free survival in the placebo group was 40 % (n = 15), compared with the Panagen arm - 53 % (n = 51). Among stage III patients, disease-free survival was 25 and 52 % for placebo (n = 8) and Panagen (n = 25) groups, respectively. Disease-free survival of patients with IIIB + C stage was as follows: placebo (n = 6)-17 % vs Panagen (n = 18)-50 %.

CONCLUSIONS

Disease-free survival rate (17 %) of patients with IIIB + C stage breast cancer receiving standard of care therapy is within the global range. Patients who additionally received Panagen demonstrate a significantly improved disease-free survival rate of 50 %. This confirms anticancer activity of Panagen.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02115984 from 04/07/2014.

Nonadherent Spheres With Multiple Myeloma Surface Markers Contain Cells that Contribute to Sphere Formation and Are Capable of Internalizing Extracellular Double-Stranded DNA

BACKGROUND

The most prominent features of cancer stem cells are asymmetric cell division, tumorigenicity, and clonogenicity. Recently one more feature of poorly differentiated cell types of various origin, including cancer stem cells, has been described. Namely, these cells can internalize extracellular DNA natively, without additional transfection procedures.

PATIENTS AND METHODS

Using our approach to trace internalization of a TAMRA (carboxy tetramethyl-rhodamine [fluorescent dye])-DNA labeled probe by poorly differentiated cell types, we isolated and characterized the cells from free-floating spheres derived from the bone marrow clonogenic aspirate of a multiple myeloma patient.

RESULTS

Nonadherent spheres display a B-cell phenotype (CD73/CD20⁺/CD45⁺/CD19^dim). Further, free-floating spheres contain 1% to 3% cells with a clonogenic potential, and these cells display a marker of poorly differentiated cell types (TAMRA⁺). Upon association with a group of ∼ 10 free-floating TAMRA^- cells, this peculiar cell type forms a sphere-forming cluster that initiates secondary aggregation of cells into a spheric structure. TAMRA⁺ and TAMRA^- cells secrete distinct sets of cytokines indicative of the paracrine regulation. Grafting experiments of intact whole spheres versus cell suspensions prepared from dispersed spheres indicate that successful engraftment only occurs in the former case.

CONCLUSION

Nonadherent 3-D cell colonies (spheres) encompass B cells with CD73/CD20⁺/CD45⁺/CD19^dim phenotype, as well as double-stranded DNA-internalizing cells. The latter cell type appears to function as a sphere-forming center. Different cells in the spheres communicate with each other by secreting specific sets of cytokines. For successful engraftment and tumor growth in mice, intact spheres containing ∼ 10⁶ cells must be used.

The Phenotypic and Functional Features of Human M2 Macrophages Generated Under Low Serum Conditions

The phenotypic and functional features of human M2 macrophages, in particular, their immunosuppressive activity, can considerably vary depending on M2 polarizing stimulus. This study was aimed at the investigation of cytokine production and pro-apoptogenic/inhibitory molecule expression in macrophages generated with GM-CSF using either standard conditions (M1) or deficiency of serum/growth factors (M2-LS cells). In contrast to M1, M2-LS cells were characterized by an enhanced content of CD206(+), B7-H1(+), FasL(+) and TRAIL(+) cells along with a decreased production of IFN-γ, IL-5, IL-6, IL-13, TNF-α, IL-17 and MCP-1. In addition, M2-LS exhibited a lower T cell stimulatory activity in MLC that was associated with the higher numbers of apoptotic and the lower numbers of proliferating T cells. B7-H1 plays a key role in M2-LS-mediated cytotoxic effects as the neutralization of B7-H1 reduces the apoptosis-inducing activity of M2-LS, while the blocking of CD206 and TRAIL reduces the cytostatic activity of M2 macrophages.

Efficiency of Cell Therapy in Liver Cirrhosis

We studied safety and clinical efficacy of transplantation of autologous bone marrow cell in complex therapy of 158 patients with chronic hepatitis and cirrhosis of the liver. The efficiency of cell therapy was assessed in 12 months after single injection of the cells. The positive response (alleviation of liver cirrhosis or stabilization of the pathological process) was observed in 70% cases. The efficacy of therapy correlated with the severity and etiology of the disease and was maximum in patients with Child-Pugh class A (in 82.5% cases) and class B liver cirrhosis (in 79% cases); in patients with class C liver cirrhosis, the positive response was achieved in 42.5% cases. In 39 patients, ultrasonic examination performed in 3 years after transplantation revealed no focal lesions or ectopic ossification foci.

Safety and Therapeutic Potential of M2 Macrophages in Stroke Treatment

Our objective was to evaluate the safety and clinical efficacy of autologous M2 macrophage transplantation in nonacute stroke patients. We also evaluated whether the intrathecal administration of macrophages influences the production of cytokines by peripheral blood cells and whether the levels of cytokines correlate with stroke severity and responsiveness to cell therapy. In this study, 13 patients (12 males and 1 female with a median age of 63 years) diagnosed with ischemic (n = 10) or hemorrhagic (n = 3) stroke were subjected to cell transplantation therapy (study group). On average, 21.9 × 10(6) autologous M2 macrophages were injected intrathecally. Thirteen matched case-control stroke patients who did not receive cell therapy comprised the control group. We did not observe any serious adverse events (i.e., intrahospital mortality, neurological worsening, and seizures) related to the cell injection. One patient in the study group and two patients in the control group died during the 6-month follow-up period due to recurrent stroke. In the study group, the NIHSS score decreased from 11 to 6 (p = 0.007) in 6 months after the therapy, whereas the patients in the control group showed a less pronounced neurological improvement (the NIHSS score decreased from 11 to 8, p = 0.07). The obvious positive response (the improvement of the NIHSS score ≥3) in the study group was observed in 75% versus 18% in the control group (pFET = 0.03). M2 cell introduction did not significantly affect the production of various cytokines. Nevertheless, pretreated levels of IL-8, IL-10, and IL-4 correlated with stroke severity. Moreover, responder patients had lower spontaneous production of IL-10, FGF-β, PDGF, VEGF, and higher stimulation indexes of IL-1β, TNF-α, IFN-γ, and IL-6 than nonresponders. These findings suggest that the intrathecal administration of autologous M2 cells in stroke patients is safe and leads to a better neurological recovery, which could be mediated through the immunomodulatory activity of M2 macrophages.

Mesenchymal stromal cells improve early lymphocyte recovery and T cell reconstitution after autologous hematopoietic stem cell transplantation in patients with malignant lymphomas

Mesenchymal stromal cells (MSCs) possess a multi-lineage potential and immunoregulatory activities and provide a great potential in cell-based technologies. However, MSC suppressive activity raises concerns regarding the possible adverse effect of MSCs on the immune recovery. The influence of autologous MSC co-transplantation on recovery of T cell subsets in patients receiving autologous hematopoietic stem cell transplantation (AHSCT) for malignant lymphomas and multiple myeloma were characterized. Co-transplantation of MSCs improved lymphocyte recovery most effectively in patients with low input of hematopoietic stem cells or low absolute lymphocyte count in apheresis product. MSC co-transplantation improved early recovery of both memory and naive T cells with more prominent effect on naive CD4(+) T cells. Patients with MSC co-transplantation showed more effective reconstitution of recent thymic emigrants. These data indicate the positive impact of MSCs on immune reconstitution and note MSC co-transplantation is feasible to optimize the outcomes of AHSCT in malignant lymphoma patients.

Comparative analysis of pathologic processes developing in mice housed in SPF vs non-SPF conditions and treated with cyclophosphamide and dsDNA preparation

In our earlier studies, we observed that when mice are treated with cyclophosphamide and fragmented exogenous dsDNA (18-30 h post cytostatic treatment), they develop a very characteristic set of symptoms and 80-90% of such animals succumb within 6-25 days. This was called "delayed death" phenomenon, and the gap between cyclophosphamide and DNA injections required for such phenotype to develop was termed "death window". We established that mice succumbed to multi-organ failure, which was caused by systemic inflammation and sepsis. These processes unfolded along with accidental involution of lymphoid organs, which resulted from the failure of CD34(+) hematopoietic stem cells to differentiate into lymphoid lineage progenitors. Here we compare SPF and non-SPF animals, and demonstrate that the major cause of systemic inflammation and sepsis observed upon such treatments is activation of an opportunistic infection. Mice of the same strain (CBA) housed under SPF conditions do not develop the characteristic symptoms, nor do they become moribund. Yet, regardless of the breeding conditions, upon synergistic action of cyclophosphamide and dsDNA, CD34(+) hematopoietic stem cells consistently fail to give rise to lymphoid lineage progenitors. We demonstrate that this differentiation defect is reversible and that population of lymphoid progenitors is restored by day 29 after cyclophosphamide injection.

[Intraocular cytokines imbalance in retinal vein occlusion and its impact on the efficacy of anti-angiogenic therapy]

AIM

To study the concentrations of intraocular cytokines in patients with retinal vein occlusion (RVO) before and after intravitreal ranibizumab injection and to compare the results with clinical activity of the disease and treatment efficacy.

MATERIAL AND METHODS

A comprehensive ophthalmological examination of 44 patients with RVO and macular edema was performed. Intraocular fluid was first collected before the intravitreal injection. Cytokines concentrations were measured using Bio-Plex Pro Human Cytokine 27-plex Panel (Bio-Rad Laboratories, USA) for flow cytometry. The test was repeated 1 month after the injection.

RESULTS

A total of 11 cytokines were reliably detected. After ranibizumab injections certain angiogenic (VEGF) and proinflammatory (IL-6, IL-8, IL-13, IL-15, MCP-1) factors appeared to be significantly suppressed. Clinical efficacy of the therapy correlated with the degree of cytokines suppression, which in turn depended on the severity of ocular involvement at baseline.

CONCLUSIONS

Retinal vein occlusion pathogenesis involves a cascade of immune and inflammatory processes, including activation of not only VEGF but also quite a few inflammatory and chemotactic factors, whose activity depends on the extent of ischemic damage in the retina.

Identification of cancer stem cells and a strategy for their elimination

It has been established previously that up to 40% of mouse CD34⁺ hematopoietic stem cells are capable of internalizing exogenous dsDNA fragments both in vivo and ex vivo. Importantly, when mice are treated with a combination of cyclophosphamide and dsDNA, the repair of interstrand crosslinks in hematopoietic progenitors is attenuated, and their pluripotency is altered. Here we show for the first time that among various actively proliferating mammalian cell populations there are subpopulations capable of internalizing dsDNA fragments. In the context of cancer, such dsDNA-internalizing cell subpopulations display cancer stem cell-like phenotype. Furthermore, using Krebs-2 ascites cells as a model, we found that upon combined treatment with cyclophosphamide and dsDNA, engrafted material loses its tumor-initiating properties which we attribute to the elimination of tumor-initiating stem cell subpopulation or loss of its tumorigenic potential.

Combination of cyclophosphamide and double-stranded DNA demonstrates synergistic toxicity against established xenografts

BACKGROUND

Extracellular double-stranded DNA participates in various processes in an organism. Here we report the suppressive effects of fragmented human double-stranded DNA along or in combination with cyclophosphamide on solid and ascites grafts of mouse Krebs-2 tumor cells and DNA preparation on human breast adenocarcinoma cell line MCF-7.

METHODS

Apoptosis and necrosis were assayed by electrophoretic analysis (DNA nucleosomal fragmentation) and by measurements of LDH levels in ascitic fluid, respectively. DNA internalization into MCF-7 was analyzed by flow cytometry and fluorescence microscopy.

RESULTS

Direct cytotoxic activity of double-stranded DNA (along or in combination with cyclophosphamide) on a solid transplant was demonstrated. This resulted in delayed solid tumor proliferation and partial tumor lysis due to necrosis of the tumor and adjacent tissues. In the case of ascites form of tumor, extensive apoptosis and secondary necrosis were observed. Similarly, MCF-7 cells showed induction of massive apoptosis (up to 45%) as a result of treatments with double-stranded DNA preparation.

CONCLUSIONS

Double-stranded DNA (along or in combination with cyclophosphamide) induces massive apoptosis of Krebs-2 ascite cells and MCF-7 cell line (DNA only). In treated mice it reduces the integrity of gut wall cells and contributes to the development of systemic inflammatory reaction.

Results of multicenter double-blind placebo-controlled phase II clinical trial of Panagen preparation to evaluate its leukostimulatory activity and formation of the adaptive immune response in patients with stage II-IV breast cancer

Background

We performed a multicenter, double-blind, placebo-controlled, phase II clinical trial of human dsDNA-based preparation Panagen in a tablet form. In total, 80 female patients with stage II-IV breast cancer were recruited.

Methods

Patients received three consecutive FAC (5-fluorouracil, doxorubicin and cyclophosphamide) or AC (doxorubicin and cyclophosphamide) adjuvant chemotherapies (3 weeks per course) and 6 tablets of 5 mg Panagen or placebo daily (one tablet every 2–3 hours, 30 mg/day) for 18 days during each chemotherapy course. Statistical analysis was performed using Statistica 6.0 software, and non-parametric analyses, namely Wilcoxon-Mann–Whitney and paired Wilcoxon tests. To describe the results, the following parameters were used: number of observations (n), median, interquartile range, and minimum-maximum range.

Results

Panagen displayed pronounced leukostimulatory and leukoprotective effects when combined with chemotherapy. In an ancillary protocol, anticancer effects of a tablet form of Panagen were analyzed. We show that Panagen helps maintain the pre-therapeutic activity level of innate antitumor immunity and induces formation of a peripheral pool of cytotoxic CD8+ perforin + T-cells. Our 3-year follow-up analysis demonstrates that 24% of patients who received Panagen relapsed or died after the therapy, as compared to 45% in the placebo cohort.

Conclusions

The data collected in this trial set Panagen as a multi-faceted “all-in-one” medicine that is capable of simultaneously sustaining hematopoiesis, sparing the innate immune cells from adverse effects of three consecutive rounds of chemotherapy and boosting individual adaptive immunity. Its unique feature is that it is delivered via gastrointestinal tract and acts through the lymphoid system of intestinal mucosa. Taken together, maintenance of the initial levels of innate immunity, development of adaptive cytotoxic immune response and significantly reduced incidence of relapses 3 years after the therapy argue for the anticancer activity of Panagen.

Trial registration

ClinicalTrials.gov NCT02115984 from 04/07/2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1142-z) contains supplementary material, which is available to authorized users.

Elevated levels of dehydroepiandrosterone as a potential mechanism of dendritic cell impairment during pregnancy

BACKGROUND

This study aimed to test the hypothesis that immune dysfunction and the increased risk of spontaneous abortion in pregnant women with hyperandrogenia (HA) are caused by the reduced tolerogenic potential of dendritic cells (DCs) that results from elevated levels of dehydroepiandrosterone sulfate (DHEAS).

METHODS

The phenotypic and functional properties of monocyte-derived DCs generated from blood monocytes from non-pregnant women, women with a normal pregnancy, or pregnant women with HA, as well as the in vitro effects of DHEAS on DCs in healthy pregnant women were investigated.

RESULTS

In a normal pregnancy, DCs were shown to be immature and are characterized by a reduced number of CD83(+) and CD25(+) DCs, the ability to stimulate type 2 T cell responses and to induce T cell apoptosis. By contrast, DCs from pregnant women with HA had a mature phenotype, were able to stimulate both type 1 (IFN-γ) and type 2 (IL-4) T cell responses, and were characterized by lower B7-H1 expression and cytotoxic activity against CD8(+) T cells. The addition of DHEAS to cultures of DCs from healthy pregnant women induced the maturation of DCs and increased their ability to activate type 1 T cell responses.

CONCLUSION

Our data demonstrated the reduction in the tolerogenic potential of DCs from pregnant women with HA, and revealed new mechanisms involved in the hormonal regulation of DCs mediated by DHEAS.

Interferon alpha induces generation of semi-mature dendritic cells with high pro-inflammatory and cytotoxic potential

Dendritic cell-based vaccines are considered as a new and promising immunotherapeutic approach for cancer treatment. However, the choice of optimal protocol of dendritic cell generation in vitro represents the major challenge. Here, we compared phenotype and functional characteristics of human monocyte-derived dendritic cells (DCs) generated in the presence of IL-4/GM-CSF (IL4-DCs) and IFNα/GM-CSF (IFN-DCs). We showed that IFN-DCs displayed semi-mature phenotype and expressed higher level of CD123, TNF-related apoptosis-inducing ligand (TRAIL) and B7-H1 molecules in comparison with IL4-DCs. LPS-stimulated IFN-DCs were characterized by greater production of Th1/pro-inflammatory (IFN-γ, IL-2, IL-1β, TNF-α, IL-17), Тh2/anti-inflammatory cytokines (IL-10, IL-5), hematopoietic growth factors (G-CSF) and chemokines (MCP-1). These data indicated more pronounced ability of IFN-DCs to induce cellular immune response as well as humoral immune response compared to IL4-DCs. LPS-stimulated IFN-DCs possessed higher direct cytotoxic activity against TRAIL-sensitive tumor cell line Jurkat and similar cytotoxicity against TRAIL-resistant tumor HEp-2 cells. Besides, IFN-DCs and IL4-DCs equally induced apoptosis of activated CD4(+) and CD8(+) T cells. These results suggest that IFN-DCs can be used as potent cell-based curative therapies for individuals with cancer.

Clinical Experience with Autologous M2 Macrophages in Children with Severe Cerebral Palsy

Stem cell-based therapy is considered to be a new approach for the treatment of cerebral palsy (CP). Given the potent anti-inflammatory activity and high regenerative potential of M2 macrophages, these cells may be an alternative source for cell transplantation. To evaluate the safety and efficacy of autologous M2 macrophages, we conducted a pilot clinical trial in 21 children with severe CP. The primary outcome measure was safety, which included assessment of mortality of any cause, immediate adverse reactions, and serious adverse effects and comorbidities during 5-year follow-up. The secondary outcome measure was functional improvement in Gross Motor Function Measure (66-item GMFM) test, Peabody Developmental Motor Scale-Fine Motor (PDMS-FM) test, Ashworth scale, MRC scale, and an easy-to-understand questionnaire for evaluation of cognitive functions in our modification. Intradural injection of M2 cells (in mean dose of 0.8 × 106/kg) into the lumbar spinal area did not induce any serious adverse events. No cases of mortality, psychomotor worsening, exacerbation of seizures, and long-term comorbidities, including tumors, were observed during a 5-year follow-up. After 3 months, GMFM score increased from 13.7 ± 7.8 to 58.6 ± 14.6, PDMS-FM score improved from 0.76 ± 0.42 to 5.05 ± 0.97, and the Ashworth score decreased from 3.8 ± 0.21 to 3.3 ± 0.24. Along with gross and fine motor function enhancement, an improvement of cognitive activity (from 1.62 ± 0.41 to 4.05 ± 0.64, according to questionnaire assessment) and reduction of seizure syndrome were registered as well. The neurological improvements did not diminish during the 5-year follow-up period. The data obtained suggest that cell therapy based on M2 macrophages is safe, does not induce early adverse effects and long-term comorbidities, and is accompanied with a significant improvement of motor and cognitive activities in severe CP patients. This manuscript is published as part of the International Association of Neurorestoratology (IANR) special issue of Cell Transplantation.