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Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system (CNS) mediated by autoreactive lymphocytes. The role of autoreactive lymphocytes in the CNS demyelination is well described, whereas very little is known about their role in remyelination during MS remission. In this study, we identified a new subpopulation of myelin-specific CD49d+CD154+ lymphocytes presented in the peripheral blood of MS patients during remission, that proliferated in vitro in response to myelin peptides. These lymphocytes possessed the unique ability to migrate towards maturing oligodendrocyte precursor cells (OPCs) and synthetize proinflammatory chemokines/cytokines. The co-culture of maturing OPCs with myelin-specific CD49d+CD154+ lymphocytes was characterized by the increase in proinflammatory chemokine/cytokine secretion that was not only a result of their cumulative effect of what OPCs and CD49d+CD154+ lymphocytes produced alone. Moreover, maturing OPCs exposed to exogenous myelin peptides managed to induce CD40-CD154-dependent CD49d+CD154+ lymphocyte proliferation. We confirmed, in vivo, the presence of CD49d+CD154+ cells close to maturating OPCs and remyelinating plaque during disease remission in the MS mouse model (C57Bl/6 mice immunized with MOG35-55) by immunohistochemistry. Three weeks after an acute phase of experimental autoimmune encephalomyelitis, CD49d+/CD154+ cells were found to be co-localized with O4+ cells (oligodendrocyte progenitors) in the areas of remyelination identified by myelin basic protein (MBP) labelling. These data suggested that myelin-specific CD49d+CD154+ lymphocytes present in the brain can interfere with remyelination mediated by oligodendrocytes probably as a result of establishing proinflammatory environment. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) associate with Argonaute (Ago), GW182, and FXR1 proteins to form RNA-induced silencing complexes (RISCs). RISCs represent a critical checkpoint in the regulation and bioavailability of miRNAs. Recent studies have revealed dysregulation of miRNAs in multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE); however, the function of RISCs in EAE and MS is largely unknown. Here, we examined the expression of Ago, GW182, and FXR1 in CNS tissue, oligodendrocytes (OLs), brain-infiltrating T lymphocytes, and CD3+splenocytes (SCs) of EAE mic, and found that global RISC protein levels were significantly dysregulated. Specifically, Ago2 and FXR1 levels were decreased in OLs and brain-infiltrating T cells in EAE mice. Accordingly, assembly of Ago2/GW182/FXR1 complexes in EAE brain tissues was disrupted, as confirmed by immunoprecipitation experiments. In parallel with alterations in RISC complex content in OLs, we found downregulation of miRNAs essential for differentiation and survival of OLs and myelin synthesis. In brain-infiltrating T lymphocytes, aberrant RISC formation contributed to miRNA-dependent proinflammatory helper T-cell polarization. In CD3+ SCs, we found increased expression of both Ago2 and FXR1 in EAE compared with nonimmunized mice. Therefore, our results demonstrate a gradient in expression of miRNA between primary activated T cells in the periphery and polarized CNS-infiltrating T cells. These results suggest that, in polarized autoreactive effector T cells, miRNA synthesis is inhibited in response to dysregulated RISC assembly, allowing these cells to maintain a highly specific proinflammatory program. Therefore, our findings may provide a mechanism that leads to miRNA dysregulation in EAE/MS. [ABSTRACT FROM AUTHOR]

One of the most important challenges in contemporary oncology is to find objective biomarkers of tumor aggressiveness, which help to identify more invasive phenotypes of the carcinoma. The purpose of this study was to investigate the relationships between the early and the late activation markers expression on T CD4+ and CD8+ cells subpopulations and certain clinicopathological characteristics of the neoplastic infiltration in order to determine their role as biomarkers for tumor behavior in squamous cell laryngeal carcinoma. Analysis of the early (CD69+, CD71+) and the late activation antigens (CD25+high, CD26+, HLA/DR+) expression on T CD4+ and CD8+lymphocytes by cytofluorymetry in 55 patients treated for squamous cell laryngeal carcinoma was performed. Clinicomorphological analysis on the basis of TNM criteria and tumor front grading, which included tumor-related features and adjacent stroma-related characteristics of the peripheral edge of infiltration was carried out. The relationships between the activation markers expression and parameters of tumor aggressiveness were investigated. Our work revealed statistically significant differences in the expression of the studied activation markers on T cells with regard to certain clinicomorphological fetaures. The expressions of CD69+ and CD71+ antigens on T CD3+CD4+ and CD3+CD8+ cells as well as CD4+HLA/DR+ markers were higher for pT3 and pT4 tumors, in comparison with pT2 carcinomas. Moreover, tumors with the smallest number of TFG points were characterized by significantly lower values of the average expression of CD3+CD69+ and CD3+CD71+ as well as CD4+HLA/DR+ markers on T lymphocytes. In addition, more aggressive and deeply infiltrating laryngeal carcinomas were most often characterized by significantly higher values of the average expression of CD69+ and CD71+ antigens on CD8+ as well as HLA/DR+ markers on CD4+. Our study confirmed the implication of the early and the late activation antigens expression on CD4+ and CD8+ T lymphocytes in clinicomorphological parameters of the tumor, especially TFG total score and depth of invasion, and their importance as indicators of the invasive phenotype of laryngeal carcinoma. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 4, pp. 593-603) [ABSTRACT FROM AUTHOR]

The role of interactions between tumor cells and autologous immunocompetent cells, the impact on the modulation of the activity of T CD4+ and CD8+ lymphocytes, as well as the influence on the regulation and determination of antitumor cellular immune response in patients with head and neck squamous cell carcinomas (HNSCC) is not completely clear. The aim of this study was to analyze early and late activation antigens expression on T cells subpopulations modified under the influence of the presence of cancer cells to investigate the regulatory mechanisms of the local cellular immune response in carcinoma of the larynx. Cytofluorymetric analysis of the early (CD69+, CD71+) and late activation markers (CD25+high, CD26+, HLA/DR+) expression on T CD3+CD4+ and CD3+CD8+ cells subpopulations in mixed cellular cultures of freshly isolated tumor cells (MLTMC) and non-cancerous normal epithelial cells (MLNCC) with immunocompetent cells was performed in 55 cases of squamous cell laryngeal carcinoma. The whole peripheral blood concentrations of IL-10 and IFN-γ in 21 h and 72 h of experiments were also measured by ELISA. The relationships between the activation markers expression depending on the type of cells used in co-cultures, as well as the level of secreted cytokines, were investigated. Our work has revealed a statistically significant dependence of cytofluorymetricresults on the presence of TMC or NCC in mixed cellular cultures. Increased expression of CD69+, CD71+ and CD25+ high, CD26+, HLA/DR+ antigens on T CD3+CD4+ and CD3+CD8+ cells was higher in MLTMC cultures, in comparison with MLNCC. We demonstrated negative significant relationships of IFN-γ and IL-10 secretion with regard to CD4+CD69+, CD8+CD69+, CD4+CD71+, CD8+CD71+ antigens expression in 21 h of experiments without mitogenic stimulation. Furthermore, this study revealed negative significant relationships of IFN-γ secretion with regard to CD4+HLA/DR+ and CD8+HLA/DR+ as well as between IL-10 concentration and CD4+HLA/DR+ in trials without PHA stimulation. Our findings have confirmed a key role for tumor cells in determining the function of T cells involved in the immunological processes and impact of neoplastic cells on modulating the activity of T CD4+ and CD8+ lymphocytes in laryngeal carcinoma. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 4, pp. 579-592) [ABSTRACT FROM AUTHOR]

Abstract: Recurrent aphthous ulcerations (RAU) are a chronic inflammatory disease with evidence of inappropriate immune response. Previous studies have suggested cell-mediated activation of immune response towards common micro-organisms of oral cavity in RAU. In this investigation, we explored cytokine production by peripheral blood mononuclear cells (PBMC) and T regulatory cell population in blood of active and remission RAU patients as crucial factors for maintenance of peripheral tolerance. Ten patients with minor RAU and 12 healthy individuals were selected for the study. Cytokine levels were analysed in supernatants using Cytometric Bead Array Kit for flow cytometry and ELISA. We have demonstrated increased production of Type 1 cytokines IL-2, IFN-γ and TNF-α as well as IL-5, IL-6 and IL-8 by peripheral blood mononuclear cells in RAU. In contrast, IL-10 and TGF-β anti-inflammatory cytokine production was decreased in RAU patients compared to healthy individuals. Moreover, we have found that CD4+CD25+high T regulatory cell proportion was decreased in RAU and represented 3.58±0.654% of CD4+ T cells in active RAU, 4.66±0.561% of CD4+ T cells in remission RAU, whereas in healthy controls CD4+CD25+high T cells represented 7.30±1.238% of CD4+ T cells (p <0.001). Thus, the obtained results indicate that disproportion in cytokine production may be contributing factor in the pathogenesis of RAU. Alteration in the number of CD4+CD25+high T regulatory cells in RAU may additionally influence the development of the disease. We propose that imbalance in pro- and anti-inflammatory cytokine network may lead to the breakdown of peripheral tolerance in RAU and the excessive immune response towards harmless micro-organisms colonized oral mucosa or self-antigens. [Copyright &y& Elsevier]

Background: Rheumatoid arthritis (RA) is an autoimmune disease with progressive activity. The RA remission was observed in women during pregnancy, but the mechanism responsible for remission is hypothetical only and concerns mechanisms of immune regulation such as lymphocyte subpopulations and interleukin production. Aims: The lymphocyte subpopulations and interleukin production in vitro in a group of healthy nonpregnant women, healthy pregnant women and pregnant women suffering from RA may help towards a better understanding of regulation of the immune processes. Methods: The investigations were performed in trimester III - 2 days after delivery and 6 weeks after delivery. Peripheral blood lymphocytes were isolated on Gradisol gradient and analysed immediately or after having been cultured for 72 hours in RPMI medium supplemented with 10% FCS. The cultures were terminated after 72 h, supernatants stored at -72°C for interleukin evaluation. The concentrations of IFN-γ, IL-2, IL-6, IL-12, TNF-α and its soluble receptors R-I, R-II were estimated in non-stimulated and PHA (Sigma, 5μg/ml) stimulated culture supernatants using ELISA Endogen kits according to the manufacturer's instructions. Results: The general pattern of T cell subpopulation distribution was similar in all analysed groups. Decreased IFN-γ, IL-12 and increased IL-6 production by lymphocytes after PHA stimulation was found in trimester III in pregnant women with RA as compared to healthy pregnant woman. Conclusion: The obtained results suggest that in pregnant women with RA the TH1 cell response predominates, contrary to healthy pregnant women with TH2 type functional response. These phenomena were not observed after delivery. [ABSTRACT FROM AUTHOR]

Abstract: This study tested the hypothesis that CD4+CD25+CD127low regulatory T (Treg) cells might induce immunosuppressive properties in apoptotic neutrophils. Treg cells are recognized as a major subset of immune cells possessing potent suppressive properties directed at T effector cells. However, Treg cells have recently been found to inhibit neutrophil function and promote their apoptosis. One of the mechanisms of action of Treg cells is the induction of other suppressor cell populations according to an infectious tolerance model. We showed that LPS-activated Treg cells promote generation of IL-10 and TGF-β1, inhibit IL-6 production by PMNs and induce the expression of heme oxygenase-1 (HO-1) and the suppressor of cytokine signaling 3 molecule (SOCS3). However, CD3/CD28-activated Treg cells were seen to promote TGF-β1 production, as well as IDO and HO-1 expression by PMNs. These findings suggest that Treg cells might play an important role in the direct control of innate immune responses through the induction of neutrophils with immunosuppressive properties that generate IL-10, TGF-β1, IDO and HO-1. [Copyright &y& Elsevier]

Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system (CNS) mediated by autoreactive lymphocytes. The role of autoreactive lymphocytes in the CNS demyelination is well described, whereas very little is known about their role in remyelination during MS remission. In this study, we identified a new subpopulation of myelin-specific CD49d + CD154 + lymphocytes presented in the peripheral blood of MS patients during remission, that proliferated in vitro in response to myelin peptides. These lymphocytes possessed the unique ability to migrate towards maturing oligodendrocyte precursor cells (OPCs) and synthetize proinflammatory chemokines/cytokines. The co-culture of maturing OPCs with myelin-specific CD49d + CD154 + lymphocytes was characterized by the increase in proinflammatory chemokine/cytokine secretion that was not only a result of their cumulative effect of what OPCs and CD49d + CD154 + lymphocytes produced alone. Moreover, maturing OPCs exposed to exogenous myelin peptides managed to induce CD40-CD154-dependent CD49d + CD154 + lymphocyte proliferation. We confirmed, in vivo, the presence of CD49d + CD154 + cells close to maturating OPCs and remyelinating plaque during disease remission in the MS mouse model (C57Bl/6 mice immunized with MOG 3 5 - 55 ) by immunohistochemistry. Three weeks after an acute phase of experimental autoimmune encephalomyelitis, CD49d + /CD154 + cells were found to be co-localized with O4 + cells (oligodendrocyte progenitors) in the areas of remyelination identified by myelin basic protein (MBP) labelling. These data suggested that myelin-specific CD49d + CD154 + lymphocytes present in the brain can interfere with remyelination mediated by oligodendrocytes probably as a result of establishing proinflammatory environment., Competing Interests: The authors declare no conflict of interest.

The critical aspect in multiple sclerosis (MS) progression involves insufficient regeneration of CNS resulting from deficient myelin synthesis by newly generated oligodendrocytes (OLs). Although many studies have focused on the role of autoreactive lymphocytes in the inflammatory-induced axonal loss, the problem of insufficient remyelination and disease progression is still unsolved. To determine the effect of myelin-specific lymphocytes on OL function in MS patients and in a mouse model of MS, we cultured myelin induced MS CD49d + CD154 + circulating lymphocytes as well as Experimental Autoimmune Encephalomyelitis (EAE) mouse brain-derived T and memory B cells with maturing oligodendrocyte precursor cells (OPCs). We found that myelin-specific CD49d + CD154 + lymphocytes affected OPC maturation toward formation of immune reactive OLs. Newly generated OLs were characterized by imbalanced myelin basic protein (MBP) and proteolipid protein (PLP) production as well as proinflammatory chemokine/cytokine synthesis. The analysis of cellular pathways responsible for OL reprogramming revealed that CD49d + CD154 + lymphocytes affected miRNA synthesis by dysregulation of polymerase II activity. miR-665 and ELL3 turned out to be the main targets of MS myelin-specific lymphocytes. Neutralization of high intracellular miR-665 concentration restored miRNA and MBP/PLP synthesis. Together, these data point to new targets for therapeutic intervention promoting CNS remyelination.

Fish oils contain several active compounds that modify cell activity and influence various functions of the human body. Shark liver oils are rich in 1-O-alkylglycerols which have strong ability to stimulate human immune system. In this review we discuss findings of the recent studies that showed antitumor properties of 1-O-alkylglycerols derived from fish oils and its effect in adjunctive treatment of several types of cancer.

One of the most important challenges in contemporary oncology is to find objective biomarkers of tumor aggressiveness, which help to identify more invasive phenotypes of the carcinoma. The purpose of this study was to investigate the relationships between the early and the late activation markers expression on T CD4(+) and CD8(+) cells subpopulations and certain clinicopathological characteristics of the neoplastic infiltration in order to determine their role as biomarkers for tumor behavior in squamous cell laryngeal carcinoma. Analysis of the early (CD69(+), CD71(+)) and the late activation antigens (CD25(+) (high), CD26(+), HLA/DR(+)) expression on T CD4+ and CD8(+) lymphocytes by cytofluorymetry in 55 patients treated for squamous cell laryngeal carcinoma was performed. Clinicomorphological analysis on the basis of TNM criteria and tumor front grading, which included tumor-related features and adjacent stroma-related characteristics of the peripheral edge of infiltration was carried out. The relationships between the activation markers expression and parameters of tumor aggressiveness were investigated. Our work revealed statistically significant differences in the expression of the studied activation markers on T cells with regard to certain clinicomorphological features. The expressions of CD69(+) and CD71(+) antigens on T CD3(+)CD4(+) and CD3(+)CD8(+) cells as well as CD4(+)HLA/DR(+) markers were higher for pT3 and pT4 tumors, in comparison with pT2 carcinomas. Moreover, tumors with the smallest number of TFG points were characterized by significantly lower values of the average expression of CD3(+)CD69(+) and CD3(+)CD71(+) as well as CD4(+)HLA/DR(+) markers on T lymphocytes. In addition, more aggressive and deeply infiltrating laryngeal carcinomas were most often characterized by significantly higher values of the average expression of CD69(+) and CD71(+) antigens on CD8(+) as well as HLA/DR(+) markers on CD4(+). Our study confirmed the implication of the early and the late activation antigens expression on CD4(+) and CD8(+) T lymphocytes in clinicomorphological parameters of the tumor, especially TFG total score and depth of invasion, and their importance as indicators of the invasive phenotype of laryngeal carcinoma.

The role of interactions between tumor cells and autologous immunocompetent cells, the impact on the modulation of the activity of T CD4(+) and CD8(+) lymphocytes, as well as the influence on the regulation and determination of antitumor cellular immune response in patients with head and neck squamous cell carcinomas (HNSCC) is not completely clear. The aim of this study was to analyze early and late activation antigens expression on T cells subpopulations modified under the influence of the presence of cancer cells to investigate the regulatory mechanisms of the local cellular immune response in carcinoma of the larynx. Cytofluorymetric analysis of the early (CD69(+), CD71(+)) and late activation markers (CD25(+) (high), CD26(+), HLA/DR(+)) expression on T CD3(+)CD4(+) and CD3(+)CD8(+) cells subpopulations in mixed cellular cultures of freshly isolated tumor cells (MLTMC) and non-cancerous normal epithelial cells (MLNCC) with immunocompetent cells was performed in 55 cases of squamous cell laryngeal carcinoma. The whole peripheral blood concentrations of IL-10 and IFN-γ in 21 h and 72 h of experiments were also measured by ELISA. The relationships between the activation markers expression depending on the type of cells used in co-cultures, as well as the level of secreted cytokines, were investigated. Our work has revealed a statistically significant dependence of cytofluorymetric results on the presence of TMC or NCC in mixed cellular cultures. Increased expression of CD69(+), CD71(+) and CD25(+) (high), CD26(+), HLA/DR(+) antigens on T CD3(+)CD4(+) and CD3(+)CD8(+) cells was higher in MLTMC cultures, in comparison with MLNCC. We demonstrated negative significant relationships of IFN-γ and IL-10 secretion with regard to CD4(+)CD69(+), CD8(+)CD69(+), CD4(+)CD71(+), CD8(+)CD71(+) antigens expression in 21 h of experiments without mitogenic stimulation. Furthermore, this study revealed negative significant relationships of IFN-g secretion with regard to CD4(+)HLA/DR(+) and CD8(+)HLA/DR(+) as well as between IL-10 concentration and CD4(+)HLA/DR(+) in trials without PHA stimulation. Our findings have confirmed a key role for tumor cells in determining the function of T cells involved in the immunological processes and impact of neoplastic cells on modulating the activity of T CD4(+) and CD8(+) lymphocytes in laryngeal carcinoma.

Introduction: Hyaluronan (HA), a component of the extracellular matrix, may regulate immune cell functions through its interactions with cellular receptors. Besides its effect on cytokine and chemokine production, its antioxidant properties have been described. However, the mechanisms of this are not fully elucidated. The aim of this study was to evaluate the relationship between HA concentration and molecular weight and its antioxidant properties towards human neutrophils. Also assessed was whether the antioxidant effect of HA is connected with a reduction in intracellular oxygen potential, which could indicate its direct effect on neutrophil respiratory burst., Materials/methods: The relationship between HA's antioxidant properties and its concentration and molecular weight was assessed by the luminol-enhanced chemiluminescence method (CL). To evaluate the effect of HA on intracellular oxygen potential selectively, the dihydrorhodamine 123 (DHR123) flow cytometric method was used., Results: Reduction of both HA molecular weight and its concentration decreased its antioxidant properties in the CL method. A selective effect of HA on intracellular oxygen potential measured by the DHR123 method was not shown., Conclusions: The antioxidant properties of HA are related to both its molecular weight and its concentration. The lack of an antioxidant effect of HA in the DHR123 test compared with a significant reduction in CL values at the same HA concentration suggests that HA acts mainly as a chemical ROI scavenger in the extracellular space.

Fish oils contain several active compounds that modify cell activity and influence various functions of the body. Shark liver oils are rich in alkylglycerols and squalene, but contain relatively low amounts of n-3 polyunsaturated fatty acids. Alkylglycerols may control immune response possibly throw modification of platelet activating factor (PAF) and diacylglycerol (DAG) production. Squalene enhances antigen presentation and induction of inflammatory response. Moreover, alkylglycerols and squalene have antitumour activity, that is possibly based on different mechanisms, ie., induction of apoptosis of neoplastic cells, suppression of signal transduction, inhibition of angiogenesis and promoting of transmembrane transport of cytotoxic agents. Shark liver oil has been found to be useful in treatment of conditions resulted from inadequate immune response, and in adjunctive treatment of several types of cancer.