Taxonomic composition and biodiversity of the gut microbiome from patients with irritable bowel syndrome, ulcerative colitis, and asthma.

To date, the association of an imbalance of the intestinal microbiota with various human diseases, including both diseases of the gastrointestinal tract and disorders of the immune system, has been shown. However, despite the huge amount of accumulated data, many key questions still remain unanswered. Given limited data on the composition of the gut microbiota in patients with ulcerative colitis (UC) and irritable bowel syndrome (IBS) from different parts of Siberia, as well as the lack of data on the gut microbiota of patients with bronchial asthma (BA), the aim of the study was to assess the biodiversity of the gut microbiota of patients with IBS, UC and BA in comparison with those of healthy volunteers (HV). In this study, a comparative assessment of the biodiversity and taxonomic structure of gut microbiome was conducted based on the sequencing of 16S rRNA genes obtained from fecal samples of patients with IBS, UC, BA and volunteers. Sequences of the Firmicutes and Bacteroidetes types dominated in all samples studied. The third most common in all samples were sequences of the Proteobacteria type, which contains pathogenic and opportunistic bacteria. Sequences of the Actinobacteria type were, on average, the fourth most common. The results showed the presence of dysbiosis in the samples from patients compared to the sample from HVs. The ratio of Firmicutes/Bacteroidetes was lower in the IBS and UC samples than in HV and higher the BA samples. In the samples from patients with intestinal diseases (IBS and UC), an increase in the proportion of sequences of the Bacteroidetes type and a decrease in the proportion of sequences of the Clostridia class, as well as the Ruminococcaceae, but not Erysipelotrichaceae family, were found. The IBS, UC, and BA samples had signif icantly more Proteobacteria sequences, including Methylobacterium, Sphingomonas, Parasutterella, Halomonas, Vibrio, as well as Escherichia spp. and Shigella spp. In the gut microbiota of adults with BA, a decrease in the proportion of Roseburia, Lachnospira, Veillonella sequences was detected, but the share of Faecalibacterium and Lactobacillus sequences was the same as in healthy individuals. A signif icant increase in the proportion of Halomonas and Vibrio sequences in the gut microbiota in patients with BA has been described for the f irst time.

Granulocyte colony-stimulating factor downregulates interferon-gamma receptor expression and stimulates interleukin-6 production in activated human macrophages.

We studied direct effects of human granulocyte colony-stimulating factor (G-CSF) on phenotypical properties of human macrophage cells in vitro. CD14+ monocyte/macrophages (Mc/Mphs) were isolated from blood of healthy donors by positive magnetic separation. G-CSF (0.01-1.0 ng/mL), when added to Mc/Mphs along with lipopolysaccharide (LPS, 1.0 µg/mL), was able to noticeably reduce proportions of CD119 (interferon-γ receptor 1)-positive cells, with no stable effects on CD16 (FcγRIII)+ and СD124 (IL-4 receptor subunit alpha)-positive cells. In addition, G-CSF markedly upregulated IL-6 production by LPS-activated Mph cells, without significantly affecting IL-1ß, IL-10 and tumor necrosis factor-α (TNF-α) secretion. Our data suggests that G-CSF could restrain Mph polarization to pro-inflammatory (M1) phenotype, thus potentially supporting pro-regenerative Mph activity with implications for immunotherapeutic interventions.

Xenogeneic cell-based vaccine therapy for colorectal cancer: Safety, association of clinical effects with vaccine-induced immune responses.

An accumulating body of evidence suggests that xenogeneic vaccines can be very effective in breaking the immune tolerance to human tumor-associated antigens (TAAs). We assessed adverse effects, as well as clinical and immune responses induced by a lyophilized xenogeneic polyantigenic vaccine (XPV) prepared from murine melanoma B16 and carcinoma LLC cells in 60 stage IV colorectal cancer patients. Neither grade III/IV toxicities, nor laboratory and clinical signs of systemic severe autoimmune disorders were documented in any XPV-treated patient. Clinical effects of various grades (complete response, partial response and disease stabilization) with duration of no shorter than 6 months was observed in 25 (41.67%) vaccinated patients. The average survival time of the XPV-treated patients was markedly longer than that of the clinically matched control patients (20 vs. 7 months). The overall 3-year survival rate in the XPV-treated and control group was 16.7% (10 patients) and 0%, respectively. Following a course of ten XPV vaccinations, peripheral blood mononuclear cell (PBMC) proliferation assays revealed increased T-cell immune responses to human Caco-2 colon adenocarcinoma-associated antigens. In addition, relative contents of CD25+ FoxP3+regulatory T-cells in patients with proven immunotherapy-mediated clinical effects (responders) were significantly decreased in the blood, which was paralleled by marked increases in serum levels of proinflammatory cytokines, such as interferon-alpha (IFN-α), IFN-É£, and interleukin-8 (IL-8). Serum levels of tumor necrosis factor-alpha (TNF-α), IL-1, IL-4, and IL-6 were not affected in both responder and non-responder patients. In conclusion, this study provides evidence for the safety, clinical feasibility and immunogenicity of xenogeneic composite cell vaccine administration in colorectal cancer patients. This is the first demonstration that clinical effects of such a vaccine are associated with vaccine-induced, proinflammatory immune responses.

Multiple-purpose immunotherapy for cancer.

Anti-cancer vaccination is a useful strategy to elicit antitumor immune responses, while overcoming immunosuppressive mechanisms. Whole tumor cells or lysates derived thereof hold more promise as cancer vaccines than individual tumor-associated antigens (TAAs), because vaccinal cells can elicit immune responses to multiple TAAs. Cancer cell-based vaccines can be autologous, allogeneic or xenogeneic. Clinical use of xenogeneic vaccines is advantageous in that they can be most effective in breaking the preexisting immune tolerance to TAAs. An attractive protocol would be to combine vaccinations with immunostimulating and/or immunosuppression-blocking modalities. It is reasonable to anticipate that combined immunotherapeutic strategies will allow for substantial improvements in clinical outcomes in the near future.

Clinically feasible approaches to potentiating cancer cell-based immunotherapies.

The immune system exerts both tumor-destructive and tumor-protective functions. Mature dendritic cells (DCs), classically activated macrophages (M1), granulocytes, B lymphocytes, aß and ɣδ T lymphocytes, natural killer T (NKT) cells, and natural killer (NK) cells may be implicated in antitumor immunoprotection. Conversely, tolerogenic DCs, alternatively activated macrophages (M2), myeloid-derived suppressor cells (MDSCs), and regulatory T (Tregs) and B cells (Bregs) are capable of suppressing antitumor immune responses. Anti-cancer vaccination is a useful strategy to elicit antitumor immune responses, while overcoming immunosuppressive mechanisms. Whole tumor cells or lysates derived thereof hold more promise as cancer vaccines than individual tumor-associated antigens (TAAs), because vaccinal cells can elicit immune responses to multiple TAAs. Cancer cell-based vaccines can be autologous, allogeneic or xenogeneic. Clinical use of xenogeneic vaccines is advantageous in that they can be most effective in breaking the preexisting immune tolerance to TAAs. To potentiate immunotherapy, vaccinations can be combined with other modalities that target different immune pathways. These modalities include 1) genetic or chemical modification of cell-based vaccines; 2) cross-priming TAAs to T cells by engaging dendritic cells; 3) T-cell adoptive therapy; 4) stimulation of cytotoxic inflammation by non-specific immunomodulators, toll-like receptor (TLR) agonists, cytokines, chemokines or hormones; 5) reduction of immunosuppression and/or stimulation of antitumor effector cells using antibodies, small molecules; and 6) various cytoreductive modalities. The authors envisage that combined immunotherapeutic strategies will allow for substantial improvements in clinical outcomes in the near future.

A balance between tissue-destructive and tissue-protective immunities: a role of toll-like receptors in regulation of adaptive immunity.

The immune system has been shown to be involved in not only the host defense against infectious pathogens but also in tissue repair processes continuously occurring in the body. Our review presents the hypothesis about the mechanism of TLR-mediated regulation of adaptive immune responses linked to the tissue destruction. In our opinion following injury to a tissue, the expression of tissue-specific determinant/MHC class II complexes on dendritic cells and macrophages are upregulated significantly due to the increased uptake of tissue debris. Consequently, T-cells become activated as a result of low affinity, but high avidity interactions between self-reactive CD4+T cells and antigen-presenting cells (APCs). The type of self antigen-induced immune responses depends on the multiple downstream signals generated by intracellular toll-like receptors (TLRs) 3, 7, 8, and 9, that discriminate "self" and "non-self" nucleic acids. Accumulating data suggest that ligation of intracellular TLRs by endogenous DNA/RNA released from necrotic cells may result in developing Th2-like responses, as well as in the alternative activation of macrophages (M2), that favor local tissue protection and compensatory cell growth. In contrast, ligation of intracellular TLRs by exogenous pathogen-derived DNA/RNA may promote Th1-driven responses, as well as classical activation of macrophages (M1), that contribute to local tissue destruction and suppress cell growth. We suggest here that the balance between the host- and pathogen-derived nucleic acids interacting with intracellular TLRs contributes to the balance between immune-mediated tissue-protective and tissue-destructive events occurring in the body.

Evaluation of the expression of isoforms of stem cell factor mRNA in fetal tissues and mononuclear cells at different stages of human development.

We studied the expression of isoforms of stem cells factor mRNA forming as a result of alternative splicing. Both isoforms of stem cell factor mRNA forming as a result of alternative splicing were found in different fetal tissues. Changes in the expression of alternative isoforms of stem cell factor in peripheral blood mononuclear cells were demonstrated from the prenatal and neonatal periods to adult organism.

Delayed results of transplantation of fetal neurogenic tissue in patients with consequences of spinal cord trauma.

We analyzed delayed effects of transplantation of nervous and hemopoietic fetal cells to patients with consequences of spinal trauma. A decrease in neurological deficit associated with pronounced improvement of functional independence was observed in 48.9% cases. The best results were observed in patients receiving cell transplantation within the first 2 years after trauma and in younger individuals. The pattern of morphological changes in the spinal cord at site of injury, severity of damage, and the method of transplantation had no appreciable effects on its delayed results.

Ontogenetic features of the expression of mRNA isoforms for leukemia-inhibitory factor in human fetal tissues and mononuclear cells.

The expression of leukemia-inhibitory factor mRNA in human fetal tissues and mononuclear cells was studied during ontogeny. The expression of mRNA isoforms for leukemia-inhibitory factor was tissue-specific at the stage of prenatal development. The transition from antenatal and neonatal development to the postnatal period was accompanied by a decrease in the expression of mRNA isoforms for leukemia-inhibitory factor in mononuclear cells.

Induction of antiidiotypic immune response with autologous T-cell vaccine in patients with multiple sclerosis.

Patients with different forms of multiple sclerosis were treated with a vaccine consisting of myelin-reactive T cells. It was found that after this treatment, lymphocytes from patients acquired the capacity to generate antiidiotypic proliferative response directed towards myelin-reactive T cells. The serum concentration of IFN-gamma decreased about 2-fold 1.5-2.0 years after the start of vaccine therapy, whereas the concentration of IL-4 increased 2-3 fold. Myelin-reactive proliferative activity of peripheral blood mononuclear cells also decreased. The results of the 2-year follow-up study revealed no side effect of T-cell vaccination in patients with cerebrospinal form of multiple sclerosis and demonstrated its possible clinical efficiency in the treatment of this disease at early stages.

Characterization of immunogenic properties of polyclonal T cell vaccine intended for the treatment of rheumatoid arthritis.

Two-staged technology for obtaining polyclonal T cell vaccine intended for the treatment of rheumatoid arthritis is described. Stage 1 includes antigen-dependent cultural selection of patient's T cells and stage 2 consists in their reproduction in the needed amounts by nonspecific mitogenic stimulation. T cell vaccination induces an effective specific anti-idiotypic immune response against T cells reactive to joint antigens. Vaccine therapy significantly reduces plasma level of IFN-gamma and increases IL-4 level. The results indicate immunological efficiency and safety of polyclonal T cell vaccine in patients with rheumatoid arthritis.

Immunological and clinical aspects of cell therapy in the treatment of aftereffects of craniocerebral injury.

Cell suspension consisting of cells from immature nervous and hemopoietic tissues was transplanted subarachnoidally to patients with craniocerebral injury aftereffects. In some patients cell therapy led to immune sensitization to donor antigens, detected by the leukocyte migration inhibition test. No signs of tissue-destructive autoimmune reactions were detected in patients receiving cell therapy. Follow-up of 56 patients showed that cell therapy was associated with significant improvement of the neurological status. No serious complications of this treatment modality were observed. Presumably, cell therapy is a safe method which can be used in the treatment of craniocerebral injury aftereffects.

Cell therapy of comatose states.

We demonstrated that liquor from adult humans can maintain proliferative activity of cells of immature nervous tissue in vitro. The paper presents the results of a retrospective clinical study of the efficiency of cell therapy in the treatment of II-III degree comatose patients with severe brain injury. Cell suspension consisting of cells derived from immature nervous and hemopoietic tissues was injected into the recipient subarachnoidal space through a cerebrospinal puncture. The mortality in the study group was 8% vs. 56% in the control group. The 1.5-year follow-up demonstrated significantly better quality of life in patients receiving cell therapy in comparison with patients of the control group. Cell therapy proved to be ineffective for patients in a comatose state caused by hypoxic encephalopathy. The study demonstrated the efficiency of cell therapy in patients with severe brain injury during the acute period of the disease.

Erythroid cells in suppressing leukemia cell growth.

This paper indicates that murine nucleated erythroid cells (EC) are able to reduce, in a dose-dependent manner, the proliferation of both L1210 lymphoma and P815 mastocytoma cells and that the leukemia cell growth inhibitory activity of unseparated bone marrow (BM) cells may be markedly augmented by their short-term culturing with erythropoietin (Epo). These results raise the intriguing possibility to utilize erythropoesis-stimulating, therapeutic strategies with the purpose of inhibiting leukemia cell growth in the body.

Cell therapy of cerebral palsy.

The paper presents the results of a controlled study of cell therapy in 30 patients with severe forms of cerebral palsy. A cell suspension from immature nervous and hemopoietic tissues was injected into the subarachnoidal space of a recipient through a spinal puncture. Immune sensitization to donor antigens (detected by suppression of lymphocyte migration) was noted in few patients. In none patients laboratory and clinical signs of tissue-destructive autoimmune reactions were observed. One year after treatment activity of the major psychomotor functions in treated patients considerably surpassed the normal. No delayed complications of cell therapy were noted. These findings suggest that cell therapy is an effective, safe, and immunologically justified method of therapy for patients with cerebral palsy.

A pendular mechanism for maintenance of the immune memory.

A possible mechanism for maintaining immune memory, based on idiotypic-anti-idiotypic interactions, is described. It is proposed that pendular dynamic swings in the levels of idiotypic antibodies (Ab1) and anti-idiotypic Ab2 may underlay immune memory. In the terms of the advanced concept, Ab dynamics in the maternal body might also play a significant role in education of the neonatal immune system.

A possible role of soluble receptors to cell growth factors in body aging.

It is assumed that production by differentiated cells of soluble receptors to cell growth factors may mediate a feedback mechanism controlling cell growth and differentiation in the body. Based on this assumption, it is hypothesized that with age a concentration of such soluble receptors in the body fluids gradually augments as a consequence of increasing a proportion of the differentiated cell pool. In the old body, when present in the cellular microenvironment at relatively high concentrations these receptors might markedly diminish ligand binding to the membrane-bound counterparts in a competitive manner and, thereby, significantly reduce cell regeneration activity. Under such conditions, the niches forming because of cell death could be being filled by connective fibers rather than newly generated cells.