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Simple Summary: As a solid tumor, melanoma is not only a tumor mass of monolithic tumor cells, but it also contains supporting stroma, extracellular matrix (ECM), and soluble molecules forming the widely recognized tumor microenvironment. The main components of the tumor microenvironment include stromal cells (endothelial cells, fibroblasts, mesenchymal stem cells, and immune cells), ECM, and soluble molecules (chemokines, cytokines, growth factors, and extracellular vesicles). The tumor microenvironment has been suggested to play a central role in tumor progression and treatment resistance. Accumulated evidence indicates that tumor maintenance, progression, and treatment resistance are determined by components of the microenvironment. Thus, targeting the components of the tumor microenvironment may have a therapeutic impact on melanoma treatment. The main topic of this paper deals with the main components of the tumor microenvironment and their impact as therapeutic targets in melanoma treatment. The role of the tumor microenvironment in tumor growth and therapy has recently attracted more attention in research and drug development. The ability of the microenvironment to trigger tumor maintenance, progression, and resistance is the main cause for treatment failure and tumor relapse. Accumulated evidence indicates that the maintenance and progression of tumor cells is determined by components of the microenvironment, which include stromal cells (endothelial cells, fibroblasts, mesenchymal stem cells, and immune cells), extracellular matrix (ECM), and soluble molecules (chemokines, cytokines, growth factors, and extracellular vesicles). As a solid tumor, melanoma is not only a tumor mass of monolithic tumor cells, but it also contains supporting stroma, ECM, and soluble molecules. Melanoma cells are continuously in interaction with the components of the microenvironment. In the present review, we focus on the role of the tumor microenvironment components in the modulation of tumor progression and treatment resistance as well as the impact of the tumor microenvironment as a therapeutic target in melanoma. [ABSTRACT FROM AUTHOR]

Abstract: Soft tissue and bone sarcomas are a rare and heterogeneous form of cancer. With standard of care treatment options including surgery, radiation, and chemotherapy, the long‐term survival is still low for high‐risk soft tissue sarcoma patients. New treatment strategies are needed. Immunotherapy offers a new potential treatment paradigm with great promise. Immunotherapy of soft tissue sarcomas dates back to Dr. Coley's first use of toxins in the late 1800s. A variety of strategies of immunotherapy have been tried in soft tissue and bone sarcomas, including various vaccines and cytokines, with limited success. Results of these early clinical trials with vaccines and cytokines were disappointing, but there are reasons to be optimistic. Recent advances, particularly with the use of adoptive T‐cell therapy and immune checkpoint inhibitors, have led to a resurgence of this field for all cancer patients. Clinical trials utilizing adoptive T‐cell therapy and immune checkpoint inhibitors in soft tissue and bone sarcomas are under way. This paper reviews the current state of evidence for the use of immunotherapy, as well as current immunotherapy strategies (vaccines, adopative T‐cell therapy, and immune checkpoint blockade), in soft tissue and bone sarcomas. By understanding the tumor microenviroment of sarcomas and how it relates to their immunoresponsiveness, better immunotherapy clinical trials can be designed, hopefully with improved outcomes for soft tissue and bone sarcoma patients. Implications for Practice: Immunotherapy is a promising treatment paradigm that is gaining acceptance for the management of several cancers, including melanoma, renal cell carcinoma, prostate cancer, and lung cancer. There is a long history of immunotherapy in the treatment of soft tissue and bone sarcomas, although with little success. It is important to understand past failures to develop future immunotherapy treatment strategies with an improved possibility of success. This article reviews the history of and current state of immunotherapy research in the treatment of soft tissue and bone sarcomas, with particular regard to vaccine trials, adoptive T‐cell therapy, and immune checkpoint blockade. [ABSTRACT FROM AUTHOR]

Normal density granulocytes (NDGs) can suppress T-cell responses in a similar way as myeloid-derived suppressor cells (MDSCs). In this study, we tested the hypothesis that NDGs from healthy donors preferentially inhibit T helper 1 (Th1) cells and investigated the myeloid-derived suppressive effect in different T-cell populations. We found that NDG-induced suppression of T-cell proliferation was contact dependent, mediated by integrin CD11b, and dependent on NDG-production of reactive oxygen species (ROS). The suppression was rapid and occurred within the first few hours of coculture. The suppression did not influence the CD8+/CD4+ ratio indicating an equal sensitivity in these populations. We further analyzed the CD4+ T helper subsets and found that NDGs induced a loss of Th1 surface marker, CD183, that was unrelated to ligand-binding to CD183. In addition, we analyzed the Th1, Th2, and Th17 cytokine production and found that all cytokine groups were suppressed when T-cells were incubated with NDGs. We therefore concluded that NDGs do not preferentially suppress Th1-cells. Instead, NDGs generally suppress Th cells and cytotoxic T-cells but specifically downregulate the Th1 marker CD183. [ABSTRACT FROM AUTHOR]

Upon antigen stimulation and co-stimulation, CD4+ T lymphocytes produce soluble factors that promote the activity of other immune cells against pathogens or modified tissues; this task must be performed in presence of a variety of environmental cytokines, nutrient, and oxygen conditions, which necessarily impact T cell function. The complexity of the early intracellular processes taking place upon lymphocyte stimulation is addressed by means of a mathematical model based on a network that integrates variable microenvironmental conditions with intracellular activating, regulatory, and metabolic signals. Besides the phenotype subsets considered in previous works (Th1, Th2, Th17, and Treg) the model includes the main early events in differentiation to the TFH phenotype. The model describes how cytokines, nutrients and oxygen availability regulate the differentiation of naïve CD4+ T cells into distinct subsets. Particularly, it shows that elevated amounts of an alltype mixture of effector cytokines under optimal nutrient and oxygen availability conduces the system towards a highly-polarized Th1 or Th2 state, while reduced cytokine levels allow the expression of the Th17, Treg or TFH subsets, or even hybrid phenotypes. On the other hand, optimal levels of an alltype cytokine mixture in combination with glutamine or tryptophan restriction implies a shift from Th1 to Th2 expression, while decreased levels of the Th2-inducing cytokine IL-4 leads to the rupture of the Th1-Th2 axis, allowing the manifestation of different (or hybrid) subsets. Modeling proposes that, even under reduced levels of pro-inflammatory cytokines, the sole action of hypoxia boost Th17 expression. [ABSTRACT FROM AUTHOR]

Cytotoxic CD8 T cells are crucial for the host antigen-specific immune response to viral pathogens. Here we report the identification of an essential role for the serine/arginine-rich splicing factor (SRSF) 1 in CD8 T cell homeostasis and function. Specifically, SRSF1 is necessary for the maintenance of normal CD8 T lymphocyte numbers in the lymphoid compartment, and for the proliferative capacity and cytotoxic function of CD8 T cells. Furthermore, SRSF1 is required for antigen-specific IFN-g cytokine responses in a viral infection challenge in mice. Transcriptomics analyses of Srsf1-deficient T cells reveal that SRSF1 controls proliferation, MAP kinase signaling and IFN signaling pathways. Mechanistically, SRSF1 controls the expression and activity of the Mnk2/p38-MAPK axis at the molecular level. Our findings reveal previously unrecognized roles for SRSF1 in the physiology and function of cytotoxic CD8 T lymphocytes and a potential molecular mechanism in viral immunopathogenesis. [ABSTRACT FROM AUTHOR]

Objective. Acute-on-chronic liver failure (ACLF) is a group of chronic liver diseases and caused by acute internal and external liver injury. Wenyang Huazhuo Tuihuang (WYHZTH) formula had a good clinical effect on promoting the resolution of jaundice. The aim of this study is to further investigate the mechanism of the WYHZTH formula in the ACLF rat model. Methods. The ACLF rat model was constructed by combining human serum albumin with LPS and D-gal. WYHZTH was used to intervene and treat. The cytokines IL-17, IL-23, IL-10, and TGF-β were detected by ELISA and fluorescence-quantitative PCR. Flow cytometry was used to detect the percentage of Th17 and Treg cells in the peripheral blood and liver tissues of each group of rats. The pathological changes in the liver tissue were detected by hematoxylin-eosin staining, immunohistochemistry, and electron microscopy. Results. Compared with the ACLF group, the WYHZTH formula and Thy significantly decreased the levels of ALT, AST, and CHE in the ACLF group. After drug intervention, apoptosis was significantly reduced. The PCNA expression decreased in the ACLF model group but increased in the WYHZTH or Thy group. Under transmission electron microscope, hepatocytes in the ACLF group showed obvious necrosis. After drug intervention, hepatocyte necrosis was reduced with most of the structure returning to normal. Conclusion. This present study demonstrated that WYHZTH formula may protect against acute-on-chronic liver failure, which may be related to the inhibition of Th17/Treg cell imbalance. [ABSTRACT FROM AUTHOR]

Tanshinone IIA (Tan II A) is widely used in the treatment of cardiovascular diseases as an active component of Salvia miltiorrhiza Bunge. It has been demonstrated to have pleiotropic effects for atherosclerosis. From the anti-inflammatory and immunomodulatory mechanism perspective, this paper reviewed major progresses of Tan IIA in antiatherosclerosis research, including immune cells, antigens, cytokines, and cell signaling pathways. [ABSTRACT FROM AUTHOR]

The cytokines generated locally in response to infection play an important role in CD8 T cell trafficking, survival, and effector function, rendering these signals prime candidates for immune intervention. In this paper, we show that localized increases in the homeostatic cytokine IL-15 induced by influenza infection is responsible for the migration of CD8 effector T cells to the site of infection. Moreover, intranasal delivery of IL-15-IL-15Rα soluble complexes (IL-15c) specifically restores the frequency of effector T cells lost in the lung airways of IL-15-deficient animals after influenza infection. Exogenous IL-15c quantitatively augments the respiratory CD8 T cell response, and continued administration of IL-15c throughout the contraction phase of the anti-influenza CD8 T cell response magnifies the resultant CD8 T cell memory generated in situ. This treatment extends the ability of these cells to protect against heterologous infection, immunity that typically depreciates over time. Overall, our studies describe what to our knowledge is a new function for IL-15 in attracting effector CD8 T cells to the lung airways and suggest that adjuvanting IL-15 could be used to prolong anti-influenza CD8 T cell responses at mucosal surfaces to facilitate pathogen elimination. [ABSTRACT FROM AUTHOR]

Cancer immunotherapy represents a potential treatment approach through non-specific and specific enhancement of the immune responses. Adoptive cell therapy (ACT) is a potential modality of immunotherapy that depends on harvesting T cells from the tumor-bearing host, activating them in vitro and infusing them back to the same host. Several cytokines, in particular IL-2, IL-7 and IL-15, have been used to enhance survival T cells in vitro. Although effective, conditioning of T cells in vitro with these cytokines requires long-term culture which results in the loss of expression of their trafficking receptors mainly CD62L. It also results in exhaustion of the activated T cells and reduction in their functions upon adoptive transfer in vivo. Our recent studies and those of other groups showed that brief (3 days) conditioning of CD8+ T cells by IL-12 in vitro can result in enhancing function of tumor-reactive CD8+ T cells. Adoptive transfer of these IL-12-conditioned CD8+ T cells into tumor-bearing mice, preconditioned with cyclophosphamide, 1 day before ACT, induced tumor eradication that was associated with generation of tumor-specific memory response. In this review, we summarize studies that indicated to the superiority of IL-12 as a potential cytokine for conditioning T cells for ACT. In addition, we discuss some of the cellular and molecular mechanisms that govern how IL-12 programs CD8+ T cells to enhance their functionality especially in vitro and its implication in combination with other ACT modalities, opening a avenue for the clinical application of this cytokine. [ABSTRACT FROM AUTHOR]

Simple Summary: Osteosarcoma is the most common primary bone tumor and has a poor prognosis. Therefore, it is important to understand the mechanism of the development of osteosarcoma to overcome therapy resistance. Several mathematical models have been developed to study the initiation and progression of many cancer types. However, there are currently no mathematical models for the progression of osteosarcoma, to the best of our knowledge. In this work, we develop a data-driven mathematical model to analyze the impact of the immune cell interactions on the growth of osteosarcoma tumors that have distinct immune patterns. Our model provides a foundation for investigating the effect of various treatments on the dynamics of key players in the primary tumor, including immune cells and cytokines, and ultimately the whole tumor. As the immune system has a significant role in tumor progression, in this paper, we develop a data-driven mathematical model to study the interactions between immune cells and the osteosarcoma microenvironment. Osteosarcoma tumors are divided into three clusters based on their relative abundance of immune cells as estimated from their gene expression profiles. We then analyze the tumor progression and effects of the immune system on cancer growth in each cluster. Cluster 3, which had approximately the same number of naive and M2 macrophages, had the slowest tumor growth, and cluster 2, with the highest population of naive macrophages, had the highest cancer population at the steady states. We also found that the fastest growth of cancer occurred when the anti-tumor immune cells and cytokines, including dendritic cells, helper T cells, cytotoxic cells, and IFN- γ , switched from increasing to decreasing, while the dynamics of regulatory T cells switched from decreasing to increasing. Importantly, the most impactful immune parameters on the number of cancer and total cells were the activation and decay rates of the macrophages and regulatory T cells for all clusters. This work presents the first osteosarcoma progression model, which can be later extended to investigate the effectiveness of various osteosarcoma treatments. [ABSTRACT FROM AUTHOR]

Neutrophils and T cells exist in close proximity in lymph nodes and inflamed tissues during health and disease. They are able to form stable interactions, with profound effects on the phenotype and function of the T cells. However, the outcome of these effects are frequently contradictory; in some systems neutrophils suppress T cell proliferation, in others they are activatory or present antigen directly. Published protocols modelling these interactions in vitro do not reflect the full range of interactions found in vivo ; they do not examine how activated and naïve T cells differentially respond to neutrophils, or whether de-granulating or resting neutrophils induce different outcomes. Here, we established a culture protocol to ask these questions with human T cells and autologous neutrophils. We find that resting neutrophils suppress T cell proliferation, activation and cytokine production but that de-granulating neutrophils do not, and neutrophil-released intracellular contents enhance proliferation. Strikingly, we also demonstrate that T cells early in the activation process are susceptible to suppression by neutrophils, while later-stage T cells are not, and naïve T cells do not respond at all. Our protocol therefore allows nuanced analysis of the outcome of interaction of these cells and may explain the contradictory results observed previously. [ABSTRACT FROM AUTHOR]

Objective This study was designed to investigate the role of mucosal-associated invariant T (MAIT) cells in gouty arthritis (GA) and their effects on osteoclastogenesis. Methods Patients with GA (n  = 61), subjects with hyperuricaemia (n  = 11) and healthy controls (n  = 30) were enrolled in this study. MAIT cells, cytokines, CD69, programmed death-1 (PD-1) and lymphocyte-activation gene 3 (LAG-3) levels were measured by flow cytometry. In vitro osteoclastogenesis experiments were performed using peripheral blood mononuclear cells in the presence of M-CSF and RANK ligand. Results Circulating MAIT cell levels were significantly reduced in GA patients. However, their capacities for IFN-γ, IL-17 and TNF-α production were preserved. Expression levels of CD69, PD-1 and LAG-3 in MAIT cells were found to be elevated in GA patients. In particular, CD69 expression in circulating MAIT cells was increased by stimulation with MSU crystals, suggesting that deposition of MSU crystals might contribute to MAIT cell activation. Interestingly, MAIT cells were found to be accumulated in synovial fluid and infiltrated into gouty tophus tissues within joints. Furthermore, activated MAIT cells secreted pro-resorptive cytokines (i.e. IL-6, IL-17 and TNF-α) and facilitated osteoclastogenesis. Conclusion This study demonstrates that circulating MAIT cells are activated and numerically deficient in GA patients. In addition, MAIT cells have the potential to migrate to inflamed tissues and induce osteoclastogenesis. These findings provide an important role of MAIT cells in the pathogenesis of inflammation and bone destruction in GA patients. [ABSTRACT FROM AUTHOR]

Background: Emerging data has suggested that Tregs, Th17, Th1 and Th2 are correlated with early immune mechanisms by controlling Plasmodium infection. Plasmodium infection appeared to impair the antigen presentation and maturation of DCs, leading to attenuation of specific cellular immune response ultimately. Hence, in this study, we aim to evaluate the relevance between DCs and Tregs/Th17 populations in the process and outcomes of infection with Plasmodium yoelii 17XL (P.y17XL).Methods: DCs detection/analysis dynamically was performed by Tregs depletion or Th17 neutralization in P.y17XL infected BALB/c mice via flow cytometry. Then the levels of cytokines production were detected using enzyme-linked mmunosorbent assay (ELISA).Results: Our results indicated that Tregs depletion or Th17 neutralization in BALB/c mice infected with P.y17XL significantly up-regulated the percentages of mDC and pDC, increased the expressions of major histocompatibility complex (MHC) class II, CD80, CD86 on DCs and the levels of IL-10/IL-12 secreted by DCs, indicating that abnormal amplification of Tregs or Th17 may damage the maturation and function of DCs during the early stage of malaria infection. Interestingly, we also found that the abnormal amplification of Th17, as well as Tregs, could inhibit the maturation of DCs.Conclusions: Tregs skewing or Th17 amplification during the early stage of malaria infection may inhibit the maturation and function of DCs by modifying the subsets of DCs, expressions of surface molecules on DCs and secretion mode of cytokines. [ABSTRACT FROM AUTHOR]

Background and Purpose: Immunosuppressive drugs have shown great promise in treating autoimmune diseases in recent years. A series of novel oxazole derivatives were screened for their immunosuppressive activity. PO-322 [1H-indole-2,3-dione 3-(1,3-benzoxazol-2-ylhydrazone)] was identified as the most effective of these compounds. Here, we have investigated the mechanism(s) underlying the inhibition of T-cell proliferation in vitro by PO-322, as well as its effects on the delayed-type hypersensitivity (DTH) response and imiquimod-induced dermatitis in vivo.Experimental Approach: T-cell proliferation and apoptosis were analysed with flow cytometry. Cell viability was assessed with a CCK-8 assay. Protein kinase activity was assessed by SelectScreen Kinase Profiling Services. The phosphorylation of signal-regulated molecules was measured by Western blot. Cytokine levels were determined by elisa. The effect of PO-322 on DTH and imiquimod-induced dermatitis was evaluated in BALB/c mice.Key Results: PO-322 inhibited human T-cell proliferation with anti-CD3/anti-CD28 mAbs or alloantigen without significant cytotoxicity. Importantly, PO-322 was a selective inhibitor of the serum- and glucocorticoid-regulated kinase 1 (SGK1) and decreased NDRG1 phosphorylation but not p70S6K, STAT5, Akt, or ERK1/2 phosphorylation. Furthermore, PO-322 inhibited IFN-γ, IL-6, and IL-17 expression but not IL-10 expression. Finally, treatment with PO-322 was safe and effective for ameliorating the DTH response and imiquimod-induced dermatitis in mice.Conclusions and Implications: PO-322 exerted immunosuppressive activity in vitro and in vivo by selectively inhibiting SGK1 activity. PO-322 represents a potential lead compound for the design and development of new drugs for the treatment of autoimmune diseases. [ABSTRACT FROM AUTHOR]

Neuroinflammation is known as a typical feature associated with many neurodegenerative diseases including Alzheimer's disease (AD) and impairs the synaptic plasticity of the hippocampus. LW-AFC is an active fraction combination being extracted from Liuwei Dihuang decoction, a classic traditional Chinese medicine prescription. This study aimed to investigate the effects of LW-AFC on synaptic plasticity in mice with lipopolysaccharide (LPS) treatment. The results showed that the administration of LPS caused fever and long-term potentiation (LTP) impairment in mice. The pretreatment with LW-AFC had an antipyretic effect on fever and improved the impaired LTP induced by LPS, alleviated the microglia and astrocytes activation in the hippocampus, regulated the abnormal T-lymphocyte subpopulation in the spleen and blood caused by LPS, and reduced the aberrant secretion of cytokines in the brain and plasma. The compounds paeoniflorin, morroniside, and loganic acid in LW-AFC regulated the TNF-α secretion in non-LPS- and LPS-stimulated BV-2 cells. These data suggest that LW-AFC improves the LPS-induced impairment of LTP and alleviates the activation of glial cells in the hippocampus, which might be associated with modulating immune responses. [ABSTRACT FROM AUTHOR]

Purpose: To characterize peripheral blood T cells in juvenile idiopathic arthritis-associated uveitis (JIAU). Methods: Blood samples were taken from children with JIAU (n = 18), JIA without ocular involvement (n = 11), idiopathic anterior uveitis (IAU, n = 12), and healthy controls (n = 11). Cells were stained for T cell surface markers, and intracellular cytokine staining was performed after cell stimulation and analyzed by flow cytometry. Results: The Th1/Th2 ratio was increased in JIAU patients. Numbers of IL-13-expressing cells an level of IL-13 and IL-10 expression per cell were increased in all patient groups; whereas, percentages of IL-5-expressing T cells were decreased. Numbers of proinflammatory Th17 cells and T cells expressing CTLA-4 were increased in all patient groups; whereas, γ/δ T cell numbers were decreased. Results from JIA and IAU were similar. Conclusion: T cell subtypes and potential T cell function are altered in pediatric patients with uveitis and arthritis as compared to healthy children. [ABSTRACT FROM AUTHOR]

Alterations of the gravitational environment are likely to modify cell behavior. Several studies have proven that T cells are sensitive to gravity alterations and that microgravity conditions may induce immunosuppression and weakened T cell immune response in humans during spaceflights. The aim of this work was to elucidate if a specific treatment of Radio Electric Asymmetric Conveyer (REAC) technology could restore, after mitogenic activation (Con A), a correct expression of cytokine IL2 gene and its receptor IL2R alpha, which are inhibited in T cells under microgravity conditions, as demonstrated in several studies. The results of this study, conducted in microgravity simulated with Random Positioning Machine (RPM), confirm the T cell activation recovery and offer the evidence that REAC technology could contribute to the understanding of T cell growth responsiveness in space, reducing the impact of weightlessness on the immune system experienced by humans in long duration space missions. [ABSTRACT FROM AUTHOR]

Good's syndrome (GS) is often accompanied by recurrent respiratory infections and chronic diarrhea. The main purpose was to evaluate the peripheral immune status of a GS patient after thymoma resection. Twenty healthy volunteers were recruited as healthy controls (HCs). Flow cytometry was applied to determine the proportions of circuiting CD4+ T cells, CD8+ T cells, γδT cells, and regulatory T (Treg) cells in our GS patient. We also examined the proliferation capability of ex vivo CD4+ T cells and detected the levels of cytokines interferon- (IFN-) γ and interleukin-17A secreted by ex vivo immune cells from this GS patient. Compared with healthy control subjects, this GS patient had fewer B cells, an inverted ratio of CD4+/CD8+ cells, and more Treg cells in his peripheral blood. Additionally, the patient's Vδ2 T cell levels were significantly decreased despite having a normal percentage of γδT cells. Ex vivo peripheral CD4+ T cells from the patient showed insufficient proliferation and division potential as well as excessive expression of PD-1. Moreover, IFN-γ was predominantly derived from CD8+ T cells in this GS patient, rather than from CD4+ T cells and γδT cells. This GS patient had impaired T and B cell immunological alternations and cytokine disruptions after thymectomy. Detailed research should focus on therapies that can adjust the immune status in such patients for a better outcome. [ABSTRACT FROM AUTHOR]

Mucosal-associated invariant T (MAIT) cells are an abundant class of innate T cells restricted by the MHC I-related molecule MR1. MAIT cells can recognize bacterially-derived metabolic intermediates from the riboflavin pathway presented by MR1 and are postulated to play a role in innate antibacterial immunity through production of cytokines and direct bacterial killing. MR1 tetramers, typically stabilized by the adduct of 5-amino-6--ribitylaminouracil (5-A-RU) and methylglyoxal (MeG), are important tools for the study of MAIT cells. A long-standing problem with 5-A-RU is that it is unstable upon storage. Herein we report an efficient synthetic approach to the HCl salt of this ligand, which has improved stability during storage. We also show that synthetic 5-A-RU•HCl produced by this method may be used in protocols for the stimulation of human MAIT cells and production of both human and mouse MR1 tetramers for MAIT cell identification. [ABSTRACT FROM AUTHOR]

Background: The role of the Th17/Treg balance in the development of experimental colitis remains poorly understood.Methods: We exploited the differential response of BALB/c mice and C57BL/6 mice towards drinking water mediated by dextran sulfate sodium (DSS) challenge.Results: DSS-resistant BALB/c mice were characterized by low levels of IFN-γ and TNF-α but high levels of IL-4, IL-6, IL-10, IL-17A, IL-17F, and colon lamina propria and mesenteric lymph node (MLN) CD4+CD25+FoxP3+ T cells when compared to C57BL/6 mice. Collectively, these data indicate the propensity of BALB/c mice towards a Th2/Th17/Treg-polarized immunity protecting these animals against DSS challenge, whereas Th1-polarization of C57BL/6 mice confers sensitivity to DSS-induced colitis.Conclusions: The intrinsic congenital capacity of mouse strains with respect to T cell proliferation determines sensitivity to experimental colitis. [ABSTRACT FROM AUTHOR]

Background: Maternal allergic disease history and impaired regulatory T-cells (Tregs) are critical risk factors for allergy development in children. However, the mechanisms that underlie these risk factors remain poorly defined. Therefore, the aim of this study was to assess whether maternal allergies affect the Tregs of offspring and lead to allergy development in childhood.Methods: A total of 332 mothers of healthy newborns (234 from no allergic mothers, 98 from allergic mothers) were recruited to this study. Detailed questionnaires were administered yearly to determine the allergy status of the mothers and the newborns from birth to 3 years of age. Cord blood samples obtained at the time of birth were analysed for Treg counts, as well Treg activity, based on their response to Toll-like receptor (TLR) stimuli such as lipid A (LPA) and peptidoglycans (PPG). Surface markers, associated genes, suppressive capacity, and cytokine levels of Tregs were also measured. Possible correlations between Treg activity and maternal or neonate allergies were assessed. In addition, environmental microbial content and other known risk factors for allergies were measured.Results: Cord blood mononuclear cells (CBMCs) from offspring with allergic mothers showed fewer CD4(+)CD25(+)FOXP3(+) T cells, lower expression levels of associated genes, and reduced cytokine production of interleukin (IL)-10 and interferon-γ (P < 0.05), especially via the PPG-TLR2 pathway. Suppression of effector T cells by Tregs from children of mothers with allergies was impaired, especially IL-13 production by Type 2 T helper (Th2) cells (P = 0.026). Children who developed allergies in the first 3 years of life had lower numbers of CD4(+)CD25(+)FOXP3(+) T cells and reduced FOXP3 expression and IL-10 production as newborns (P < 0.05). Maternal allergic background was identified as a risk factor for allergy development in the children (Odds ratio (OR) = 2.46, 95 % CI = 1.05-5.79); while declining Treg numbers, IL-10 production, and FOXP3 expression in neonates (PPG and LPA stimulated) were identified as independent risk factors for allergic diseases in offspring at 3 years of age after adjusting for maternal allergic history and environmental factors (P < 0.05).Conclusion: Maternal allergy correlated with impaired Tregs in neonates, and this could enhance the susceptibility of offspring to allergic diseases in early childhood due to an imbalance of Th1 and Th2 cells. [ABSTRACT FROM AUTHOR]

The article discusses research on the link between neutrophil and T cell migration during influenza virus infection. It references the study "Neutrophil trails guide influenza-specific CD8+ T cells in the airways" in the 2015 issue of the journal "Science." The study shows that activated CD8+ T cells migration was enhanced on coverslips that were exposed to migrating neutrophils.

Immune responses often take place where nutrients and O2 availability are limited. This has an impact on T cell metabolism and influences activation and effector functions. T cell proliferation and expansion are associated with increased consumption of glutamine which is needed in a number of metabolic pathways and regulate various physiological processes. The first step in endogenous glutamine metabolism is reversible and is regulated by glutaminase (GLS1 and GLS2) and glutamine synthase (GLUL). There are two isoforms of GLS1, Kidney type glutaminase (KGA) and Glutaminase C (GAC). The aim of this study is to investigate the expression, localization and role of GLS1 and GLUL in naïve and activated human CD4+ T cells stimulated through the CD3 and CD28 receptors under normoxia and hypoxia. In proliferating cells, GAC was upregulated and KGA was downregulated, and both enzymes were located to the mitochondria irrespective of O2 levels. By contrast GLUL is localized to the cytoplasm and was upregulated under hypoxia. Proliferation was dependent on glutamine consumption, as glutamine deprivation and GLS1 inhibition decreased proliferation and expression of CD25 and CD226, regardless of O2 availability. Again irrespective of O2, GLS1 inhibition decreased the proportion of CCR6 and CXCR3 expressing CD4+ T cells as well as cytokine production. We propose that systemic Th cell activation and expansion might be dependent on glutamine but not O2 availability. [ABSTRACT FROM AUTHOR]

Background: Chronic Chagas disease presents different clinical manifestations ranging from asymptomatic (namely indeterminate) to severe cardiac and/or digestive. Previous results have shown that the immune response plays an important role, although no all mechanisms are understood. Immunoregulatory mechanisms such as apoptosis are important for the control of Chagas disease, possibly affecting the morbidity in chronic clinical forms. Apoptosis has been suggested to be an important mechanism of cellular response during T. cruzi infection. We aimed to further understand the putative role of apoptosis in Chagas disease and its relation to the clinical forms of the disease.Methods: Apoptosis of lymphocytes, under antigenic stimuli (soluble T. cruzi antigens - TcAg) where compared to that of non-stimulated cells. Apoptosis was evaluated using the expression of annexin and caspase 3(+) by T cells and the percentage of cells positive evaluated by flow cytometry. In addition activation and T cell markers were used for the identification of TCD4(+) and TCD8(+) subpopulations. The presence of intracellular and plasma cytokines were also evaluated. Analysis of the activation status of the peripheral blood cells showed that patients with Chagas disease presented higher levels of activation determined by the expression of activation markers, after TcAg stimulation. PCR array were used to evaluate the contribution of this mechanism in specific cell populations from patients with different clinical forms of human Chagas disease.Results: Our results showed a reduced proliferative response associated a high expression of T CD4(+)CD62L(-) cells in CARD patients when compared with IND group and NI individuals. We also observed that both groups of patients presented a significant increase of CD4(+) and CD8(+) T cell subsets in undergoing apoptosis after in vitro stimulation with T. cruzi antigens. In CARD patients, both CD4(+) and CD8(+) T cells expressing TNF-α were highly susceptible to undergo apoptosis after in vitro stimulation. Interestingly, the in vitro TcAg stimulation increased considerably the expression of cell death TNF/TNFR superfamily and Caspase family receptors genes in CARD patients.Conclusions: Taken together, our results suggest that apoptosis may be an important mechanism for the control of morbidity in T. cruzi infection by modulating the expression of apoptosis genes, the cytokine environment and/or killing of effector cells. [ABSTRACT FROM AUTHOR]

Background: TLR4/MD-2 complex-mediated MyD88-dependent activation of NF-κB and Akt promotes tumor-associated immunosuppression in epithelial ovarian cancer (EOC) via induction of immunesuppressive cytokines and indoleamine 2,3-dioxygenase (IDO). Atractylenolide I (AO-1) is a naturally occurring sesquiterpene lactone known to change the conformational ensemble of human MD-2 on EOC cells. This study examined the modulation by AO-1 of TLR4/MD-2 complex-mediated MyD88/NF-κB signaling.Methods: The expression and activation of NF-κB, Akt and IDO1 by MyD88(+) EOC SKOV3 cells was determined using western blot; the TLR4/MD-2 complex on SKOV3 cells and the phenotype of T lymphocytes were determined using flow cytometry; IDO activity was evaluated by measuring L-kynurenine; Immunesuppressive cytokines were detected using ELISA; T-cell proliferation to mitogen stimulation was assessed by MTT assay; the cytotoxicity of lymphocytes and NK cells was measured using LDH-cytotoxicity assay.Results: AO-1 could down-regulate expression of TLR4/MD-2 complex, resulting in downregulation of MyD88/NF-κB signaling and activation of NF-κB, Akt and IDO1 and secretion of IL-6, TGF-β1, VEGF and IL-17A by EOC SKOV3 cells, and further reduce increased levels of regulatory T cells (Treg cells) and improve decreased proliferative response and antitumor cytotoxicity of T lymphocytes exposed to EOC SKOV3 cell supernatant.Conclusion: AO-1 may reverse EOC cell-mediated immunosuppression through blocking TLR4/MD-2 complex-mediated MyD88/NF-κB signaling. [ABSTRACT FROM AUTHOR]

Background: Experimental autoimmune encephalomyelitis (EAE) in the common marmoset monkey (Callithrix jacchus) is a relevant preclinical model for translational research into immunopathogenic mechanisms operating in multiple sclerosis (MS). Prior studies showed a core pathogenic role of T and B cells specific for myelin oligodendrocyte glycoprotein (MOG). However, in those studies, the quality of the response against MOG epitopes was strongly biased by bacterial antigens in the complete Freund's adjuvant (CFA), in which the immunizing recombinant human (rh) MOG protein had been formulated. In response to the need of a more refined EAE model, we have tested whether disease could also be induced with rhMOG in incomplete Freund's adjuvant (IFA).Method: Marmosets were immunized with rhMOG emulsified in IFA in the dorsal skin. Monkeys that did not develop neurological deficit were given booster immunizations at 28-day interval with the same antigen preparation. In a second experiment, three marmoset twin pairs were sensitized against MOG peptides in IFA to study a possibility for suppressive activity towards pathogenic T cells directed against the encephalitogenic epitope MOG40-48.Results: Despite the absence of strong danger signals in the rhMOG/IFA inoculum, all monkeys developed clinically evident EAE symptoms. Moreover, in all monkeys, demyelinated lesions were present in the white matter and in two cases also in the cortical grey matter. Immune profiling at height of the disease showed a dominant T cell response against the overlapping peptides 14-36 and 24-46, but reactivity against the pathogenically most relevant peptide 34-56 was conspicuously absent. In the second experiment, there was an indication for a possible suppressive mechanism.Conclusions: Immunization of marmoset monkeys with rhMOG in IFA elicits clinical EAE in all animals. Moreover, rhMOG contains pathogenic and regulatory epitopes, but the pathogenic hierarchy of rhMOG epitopes is strongly influenced by the adjuvant in which the protein is formulated. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Tregs) are potent immunosuppressive cells and essential for inducing immune tolerance. Recent studies have reported that Tregs and Tregs related cytokines can inhibit the antitumor activity of cytokine-induced killer (CIK) cells, but dendritic cells co-cultured CIK (DC-CIK) cells can be used for induction of a specific immune response by blocking of Tregs and TGF-β, IL-10. As a novel identified cytokine, IL-35 is specially produced by Tregs and plays an essential role in immune regulation. However, it remains unknown whether IL-35 roles in tumor immunotherapy mediated by CIK and DC-CIK cells. In this study, we cultured CIK and DC-CIK cells from the same healthy adult samples, and investigated their phenotype, proliferation, cytotoxic activity against leukemia cell lines K562 and NB4 by FCM and CCK-8, measured IL-35, TGF-β and IL-10 protein by ELISA, detected Foxp3, IL-35 and IL-35 receptor mRNA by Real-time PCR, respectively. We found Tregs and IL-35 concomitantly expanded by a time-dependent way during the generation of CIK cells, but DC significantly down-regulated the expression of them and simultaneously up-regulated the proliferation ability as well as cytotoxic activity of CIK cells against leukemia cell lines. Therefore, our data suggested that DC decreased concomitant expanded Tregs and Tregs related IL-35 in CIK cells and might contribute to improve their cytotoxicity against leukemia cells in vitro. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the anti-inflammatory efficacy of Daclizumab, an anti-interleukin-2 receptor drug, in an experimental uveitis model upon a subcutaneous injection of lipopolysaccharide into Lewis rats, a valuable model for ocular acute inflammatory processes. The integrity of the blood-aqueous barrier was assessed 24 h after endotoxin-induced uveitis by evaluating two parameters: cell count and protein concentration in aqueous humors. The histopathology of all the ocular structures (cornea, lens, sclera, choroid, retina, uvea, and anterior and posterior chambers) was also considered. Enzyme-linked immunosorbent assays of the aqueous humor samples were performed to quantify the levels of the different chemokine and cytokine proteins. Similarly, a biochemical analysis of oxidative stress-related markers was also assessed. The inflammation observed in the anterior chamber of the eyes when Daclizumab was administered with endotoxin was largely prevented since the aqueous humor protein concentration substantially lowered concomitantly with a significant reduction in the uveal and vitreous histopathological grading. Th1 lymphocytes-related cytokines, such as Interleukin-2 and Interferon-γ, also significantly reduced with related anti-oxidant systems recovery. Daclizumab treatment in endotoxin-induced uveitis reduced Th1 lymphocytes-related cytokines, such as Interleukin-2 and Interferon gamma, by about 60–70% and presented a preventive role in endotoxin-induced oxidative stress. This antioxidant protective effect of Daclizumab may be related to several of the observed Daclizumab effects in our study, including IL-6 cytokine regulatory properties and a substantial concomitant drop in INFγ. Concurrently, Daclizumab treatment triggered a significant reduction in both the uveal histopathological grading and protein concentration in aqueous humors, but not in cellular infiltration. [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) are key activators of cellular immune responses through their capacity to induce naïve T cells and sustained effector T cell responses. This capacity is a function of their superior efficiency of antigen presentation via MHC class I and class II molecules, and the expression of co-stimulatory cell surface molecules and cytokines. Maturation of DCs is induced by microbial factors via pattern recognition receptors such as Toll-like receptors, pro-inflammatory cytokines or cognate interaction with CD4+ T cells. Here we show that, unexpectedly, the PanDR helper T cell epitope PADRE, a generic T helper cell antigen presented by a large fraction of HLA-DR alleles, when delivered in particle-bound form induced maturation of human DCs. The DCs that received the particle-bound PADRE displayed all features of fully mature DCs, such as high expression of the co-stimulatory molecules CD80, CD86, CD83, the MHC-II molecule HLA-DR, secretion of high levels of the biologically active IL-12 (IL-12p70) and induction of vigorous proliferation of naïve CD4+ T cells. Furthermore, the maturation of DCs induced by particle-bound PADRE was shown to involve sphingosine kinase, calcium signaling from internal sources and downstream signaling through the MAP kinase and the p72syk pathways, and finally activation of the transcription factor NF-κB. Based on our findings, we propose that particle-bound PADRE may be used as a DC activator in DC-based vaccines. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) reside in almost all of the body tissues, where they undergo self-renewal and multi-lineage differentiation. MSCs derived from different tissues share many similarities but also show some differences in term of biological properties. We aim to search for significant differences among various sources of MSCs and to explore their implications in physiopathology and clinical translation. We compared the phenotype and biological properties among different MSCs isolated from human term placental chorionic villi (CV), umbilical cord (UC), adult bone marrow (BM) and adipose (AD). We found that CD106 (VCAM-1) was expressed highest on the CV-MSCs, moderately on BM-MSCs, lightly on UC-MSCs and absent on AD-MSCs. CV-MSCs also showed unique immune-associated gene expression and immunomodulation. We thus separated CD106+cells and CD106−cells from CV-MSCs and compared their biological activities. Both two subpopulations were capable of osteogenic and adipogenic differentiation while CD106+CV-MSCs were more effective to modulate T helper subsets but possessed decreased colony formation capacity. In addition, CD106+CV-MSCs expressed more cytokines than CD106−CV-MSCs. These data demonstrate that CD106 identifies a subpopulation of CV-MSCs with unique immunoregulatory activity and reveal a previously unrecognized mechanism underlying immunomodulation of MSCs. [ABSTRACT FROM AUTHOR]

Background: Most infections with human papillomavirus (HPV) are resolved without clinical intervention, but a minority evolves into chronic lesions of distinct grades, including cervical-uterine cancer. It is known that in most cases the immune system mediates elimination of HPV infection. However, the mechanism of immune evasion leading to HPV persistence and development of early cervical lesions is not fully understood. The aim of the present work was to evaluate the potential of peripheral blood leukocytes (PBL) from low-grade squamous intraepitheliallesions (LSIL) patients to be activated ex-vivo by vaccine antigens, the participation of cytotoxic lymphocytes and regulatory T cells, and to determine the secretion of Th1 and Th2 cytokines mediated by stimulation of T cell receptors.Results: We found that PBL from LSIL patients showed a significantly lower proliferation rate to vaccine antigens as compared to that of healthy donors, even though there was not a difference in the presence of antibodies to those antigens in sera from both groups. We did not find differences in either the frequency of CD4 + CD25 + FoxP3+ in PBL, or the levels of IL-4, IL-5 and IL-10 in plasma or conditioned media from PBL incubated with TcR agonistsin vitro, between the two groups. However, we detected a lower production of IL-2 and a higher proportion of CD8 + IFNγ + cells in PBL from LSIL patients as compared with PBL from normal donors. We also observed that PB L from patients infected by HPV-16 and -18 were not able to proliferate in the presence of soluble HPV antigens added to the culture; however, a high level of proliferation was attained when these antigens were presented by activated dendritic cells.Conclusions: Our results suggest that the immunodeficiency reported in LSIL patients could be due to the inability of specific cytotoxic T lymphocytes that for some unknown reason are present but unable to mount a response when challenged with their antigens, probably related to an in situ IL-2 production deficiency. [ABSTRACT FROM AUTHOR]

Severe combined immunodeficiency (SCID) patients with an inactivating mutation in recombination activation gene 1 (RAG1) lack B and T cells due to the inability to rearrange immunoglobulin (Ig) and T-cell receptor (TCR) genes. Gene therapy is a valid treatment option for RAG-SCID patients, especially for patients lacking a suitable bone marrow donor, but developing such therapy has proven challenging. As a preclinical model for RAG-SCID, we used Rag1-/- mice and lentiviral self-inactivating (SIN) vectors harboring different internal elements to deliver native or codon-optimized human RAG1 sequences. Treatment resulted in the appearance of B and T cells in peripheral blood and developing B and T cells were detected in central lymphoid organs. Serum Ig levels and Ig and TCR Vβ gene segment usage was comparable to wild-type (WT) controls, indicating that RAG-mediated rearrangement took place. Remarkably, relatively low frequencies of B cells produced WT levels of serum immunoglobulins. Upon stimulation of the TCR, corrected spleen cells proliferated and produced cytokines. In vivo challenge resulted in production of antigen-specific antibodies. No leukemia development as consequence of insertional mutagenesis was observed. The functional reconstitution of the B- as well as the T-cell compartment provides proof-of-principle for therapeutic RAG1 gene transfer in Rag1-/- mice using lentiviral SIN vectors. [ABSTRACT FROM AUTHOR]

Purpose: to review the function and genetics of killer immunoglobulin-like receptors (KIRs) and studies of KIR genetic associations with uveitis. Methods: Review of published studies. Results: KIRs are receptors on NK and some T cells. They may inhibit or activate cellular function, such as cytotoxicity and cytokine production. Studies have been published examining KIR gene associations with birdshot chorioretinopathy (BCR), Vogt-Koyanagi-Harada (VKH) disease, and HLA-B27-associated acute anterior uveitis (AAU) and axial spondyloarthropathy. Evidence for increased activating and/or less inhibitory KIR and HLA gene combinations was found for BCR and VKH disease. In HLA-B27-associated disease, a trend toward decreased activation and stronger inhibition was found, except for the weakly inhibitory 3DL1 and Bw4T80 combination. This latter combination was also found to confer risk in BCR. Conclusions: KIR genetics are complex, as are the functions of KIR-bearing cells. Nonetheless, evidence for KIRs in the pathogenesis of uveitis has been found. [ABSTRACT FROM AUTHOR]

Background: Host T-cell responses are associated with favorable outcomes in epithelial ovarian cancer (EOC), but it remains unclear how best to promote these responses in patients. Toward this goal, we evaluated a panel of clinically relevant cytokines for the ability to enhance multiple T-cell effector functions (polyfunctionality) in the native tumor environment. Methodology/Principal Findings: Experiments were performed with resident CD8+ and CD4+ T cells in bulk ascites cell preparations from high-grade serous EOC patients. T cells were stimulated with α-CD3 in the presence of 100% autologous ascites fluid with or without exogenous IL-2, IL-12, IL-18 or IL-21, alone or in combination. T-cell proliferation (Ki-67) and function (IFN-γ, TNF-α, IL-2, CCL4, and CD107a expression) were assessed by multi-parameter flow cytometry. In parallel, 27 cytokines were measured in culture supernatants. While ascites fluid had variable effects on CD8+ and CD4+ T-cell proliferation, it inhibited T-cell function in most patient samples, with CD107a, IFN-γ, and CCL4 showing the greatest inhibition. This was accompanied by reduced levels of IL-1β, IL-1ra, IL-9, IL-17, G-CSF, GM-CSF, Mip-1α, PDGF-bb, and bFGF in culture supernatants. T-cell proliferation was enhanced by exogenous IL-2, but other T-cell functions were largely unaffected by single cytokines. The combination of IL-2 with cytokines engaging complementary signaling pathways, in particular IL-12 and IL-18, enhanced expression of IFN-γ, TNF-α, and CCL4 in all patient samples by promoting polyfunctional T-cell responses. Despite this, other functional parameters generally remained inhibited. Conclusions/Significance: The EOC ascites environment disrupts multiple T-cell functions, and exogenous cytokines engaging diverse signaling pathways only partially reverse these effects. Our results may explain the limited efficacy of cytokine therapies for EOC to date. Full restoration of T-cell function will require activation of signaling pathways beyond those engaged by IL-2, IL-12, IL-18, and IL-21. [ABSTRACT FROM AUTHOR]

The International Society for Biological Therapy of Cancer (iSBTc) is one of the "premier destinations for interaction and innovation in the cancer biologics community". It provides a primer course each year during the annual meeting to address the most important areas of tumor immunology and immunotherapy. The course has been given by prominent investigators in the area of interest, covering the core principles of cancer immunology and immunotherapy. The target audience for this program includes investigators from academic, regulatory, and biopharmaceutical venues. The program goal is to enable the attendees to learn the current status and the most recent advances in biologic therapies, and to leverage this knowledge towards the improvement of cancer therapy. The 2008 immunologic primer course was held on October 30 at the 23rd Annual meeting of iSBTc in San Diego, CA. Nine internationally renowned investigators gave excellent presentations on different topics. The topics covered in this primer included: (1) cytokines in cancer immunology; (2) anti-angiogenic therapy; (3) end stage: immune killing of tumors; (4) blocking T cell checkpoints; (5) approach to identification and therapeutic exploitation of tumor antigens; (6) T regulatory cells; (7) adoptive T cell therapy; (8) immune monitoring of cancer immunotherapy; and (9) immune adjuvants. We summarized the topics in this primer for public education. The related topic slides and schedule can be accessed online http://www.isbtc.org/meetings/am08/primer08. [ABSTRACT FROM AUTHOR]

Tight control of T-cell proliferation and effector function is essential to ensure an effective but appropriate immune response. Here, we reveal that this is controlled by the metalloprotease-mediated cleavage of LAG-3, a negative regulatory protein expressed by all activated T cells. We show that LAG-3 cleavage is mediated by two transmembrane metalloproteases, ADAM10 and ADAM17, with the activity of both modulated by two distinct T-cell receptor (TCR) signaling-dependent mechanisms. ADAM10 mediates constitutive LAG-3 cleavage but increases ∼12-fold following T-cell activation, whereas LAG-3 shedding by ADAM17 is induced by TCR signaling in a PKCθ-dependent manner. LAG-3 must be cleaved from the cell surface to allow for normal T-cell activation as noncleavable LAG-3 mutants prevented proliferation and cytokine production. Lastly, ADAM10 knockdown reduced wild-type but not LAG-3−/− T-cell proliferation. These data demonstrate that LAG-3 must be cleaved to allow efficient T-cell proliferation and cytokine production and establish a novel paradigm in which T-cell expansion and function are regulated by metalloprotease cleavage with LAG-3 as its sole molecular target. [ABSTRACT FROM AUTHOR]

12F6 is a murine anti-human CD3 monoclonal antibody, which competes with OKT3 for binding to human T cells and possesses more effective T-cell suppression and activation properties compared to OKT3. It thus exhibits the potential to be developed as an immunoregulation agent for manipulating T-cell functions and preventing acute allograft rejection. In an attempt to minimize the immunogenicity of murine 12F6 (m12F6) for potential clinical application, a humanized version of 12F6, denoted as hu12F6, was successfully constructed by complementary determining region (CDR) grafting and shown to maintain both T-cell activation and suppression activities similar to m12F6. Furthermore, in order to reduce the first dose reaction syndrome caused by T-cell activation following the first administration of anti-CD3 antibodies, two amino acid mutations were introduced into the Fc region of hu12F6, resulting in the Fc-mutated 12F6 humanized antibody (hu12F6mu). This Fc-mutated version displayed a similar antigen-binding affinity and specificity compared with hu12F6 and m12F6 but with much weaker FcR binding activity. hu12F6mu was shown to be much less potent in the induction of T-cell proliferation, cytokine release (tumour necrosis factor-α, interferon-γ and interleukin-10) and early activation marker expression on the cell surface (CD69 and CD25) than parental 12F6 and OKT3 did. In contrast, hu12F6mu was effective in modulating T-cell receptor/CD3 and inhibiting mixed lymphocyte reaction with a similarity as compared to m12F6 and OKT3. In conclusion, the resultant hu12F6mu was much less mitogenic to T cells but retained potent immunosuppression, suggesting it might be an alternative to OKT3 as an immunosuppressive drug with less immunogenicity and toxicity for clinical application. [ABSTRACT FROM AUTHOR]

Background: This study compared Th1-Th2 cytokine profiles in a subgroup of recurrent aborters who had an abortion with those in a subgroup of recurrent aborters who had a successful pregnancy.Methods: Fifty-four women with a history of at least three normal pregnancies, 24 women with a history of recurrent spontaneous abortion (RSA) followed by abortion (RSA-->A) and 39 women with a history of RSA followed by normal pregnancy (RSA-->N) were studied. Blood samples and placentas were obtained at the time of delivery or abortion; peripheral blood mononuclear cells were stimulated separately with phytohaemagglutinin and with autologous placental cells, and the secreted cytokines estimated.Results: Peripheral blood mononuclear cells from the RSA-->N subgroup secreted higher concentrations of Th1-type cytokines as compared with normal pregnant women, indicating a higher Th1 bias in these women. However, women in the RSA-->N subgroup had significantly higher concentrations of Th2 cytokines as compared with women in the RSA-->A subgroup. A comparison of Th1:Th2 cytokine ratios indicated a higher Th2 bias in RSA-->N women as compared with RSA-->A women.Conclusions: We conclude that abortion-prone women who proceed to have successful pregnancy are more Th2-biased than abortion-prone women who abort, and that recurrent aborters who undergo spontaneous abortion have a stronger Th1 bias than aborters who have normal pregnancy. [ABSTRACT FROM AUTHOR]

The absence of reliable, robust, and non-invasive biomarkers for anti- Programmed cell death protein 1 (PD-1) immunotherapy is an urgent unmet medical need for the treatment of cancer patients. No predictive biomarkers have been established based on the direct assessment of T cell functions, the primary mechanism of action of anti-PD-1 therapy. In this study, we established a model system to test T cell functions modulated by Nivolumab using anti-CD3 monoclonal antibody (mAb)-stimulated peripheral blood mononuclear cells (PBMCs), and characterized T cell functions primarily based on the knowledge gained from retrospective observations of patients treated with anti-PD-1 immunotherapy. During a comprehensive cytokine profile assessment to identify potential biomarkers, we found that Nivolumab increases expression of T helper type 1 (Th1) associated cytokines such as interferon-γ (IFN-γ) and interleukin-2 (IL-2) in a subset of donors. Furthermore, Nivolumab increases production of Th2, Th9, and Th17 associated cytokines, as well as many proinflammatory cytokines such as IL-6 in a subset of donors. Conversely, Nivolumab treatment has no impact on T cell proliferation, expression of CD25, CD69, or Granzyme B, and only modestly increases in the expansion of regulatory T cells. Our results suggest that assessment of cytokine production using a simple PBMC-based T cell functional assay could be used as a potential predictive marker for anti-PD-1 immunotherapy. [ABSTRACT FROM AUTHOR]

The failure of therapies directed at targets within cancer cells highlight the necessity for a paradigm change in cancer therapy. The attention of researchers has shifted towards the disruption of cancer cell interactions with the tumor microenvironment. A typical example of such a disruption is the immune checkpoint cancer therapy that disrupts interactions between the immune and the cancer cells. The interaction of cancer antigens with T cells occurs in the immunological synapses. This is characterized by several special features, i.e., the proximity of the immune cells and their target cells, strong intercellular adhesion, and secretion of signaling cytokines into the intercellular cleft. Earlier, we hypothesized that the cancer-associated fibroblasts interacting with cancer cells through a synapse-like adhesion might play an important role in cancer tumors. Studies of the interactions between cancer cells and cancer-associated fibroblasts showed that their clusterization on the membrane surface determined their strength and specificity. The hundreds of interacting pairs are involved in the binding that may indicate the formation of synapse-like structures. These interactions may be responsible for successful metastasis of cancer cells, and their identification and disruption may open new therapeutic possibilities. [ABSTRACT FROM AUTHOR]

Background: Human primary myeloma (MM) cells do not survive in culture; current in vitro and in vivo systems for growing these cells are limited to coculture with a specific bone marrow (BM) cell type or growth in an immunodeficient animal model. The purpose of the study is to establish an interactive healthy donor whole BM based culture system capable of maintaining prolonged survival of primary MM cells. This normal BM (NBM) coculture system is different from using autologous BM that is already affected by the disease.Methods: Whole BM from healthy donors was cultured in medium supplemented with BM serum from MM patients for 7 days, followed by 7 days of coculture with CD138-selected primary MM cells or MM cell lines. MM cells in the coculture were quantified using flow cytometry or bioluminescence of luciferase-expressing MM cells. T-cell cytokine array and proteomics were performed to identify secreted factors.Results: NBM is composed of adherent and nonadherent compartments containing typical hematopoietic and mesenchymal cells. MM cells, or a subset of MM cells, from all examined cases survived and grew in this system, regardless of the MM cells' molecular risk or subtype, and growth was comparable to coculture with individual stromal cell types. Adherent and nonadherent compartments supported MM growth, and this support required patient serum for optimal growth. Increased levels of MM growth factors IL-6 and IL-10 along with MM clinical markers B2M and LDHA were detected in supernatants from the NBM coculture than from the BM cultured alone. Levels of extracellular matrix factors (e.g., MMP1, HMCN1, COL3A1, ACAN) and immunomodulatory factors (e.g., IFI16, LILRB4, PTPN6, AZGP1) were changed in the coculture system. The NBM system protected MM cells from dexamethasone but not bortezomib, and effects of lenalidomide varied.Conclusions: The NBM system demonstrates the ability of primary MM plasma cells to interact with and to survive in coculture with healthy adult BM. This model is suitable for studying MM-microenvironment interactions, particularly at the early stage of engagement in new BM niches, and for characterizing MM cell subpopulations capable of long-term survival through secretion of extracellular matrix and immune-related factors. [ABSTRACT FROM AUTHOR]

Background: Somatic afferent input to the spinal cord from a peripheral inflammatory site can modulate the peripheral response. However, the intracellular signaling mechanisms in the spinal cord that regulate this linkage have not been defined. Previous studies suggest spinal cord p38 mitogen-activated protein (MAP) kinase and cytokines participate in nociceptive behavior. We therefore determined whether these pathways also regulate peripheral inflammation in rat adjuvant arthritis, which is a model of rheumatoid arthritis.Methods and Findings: Selective blockade of spinal cord p38 MAP kinase by administering the p38 inhibitor SB203580 via intrathecal (IT) catheters in rats with adjuvant arthritis markedly suppressed paw swelling, inhibited synovial inflammation, and decreased radiographic evidence of joint destruction. The same dose of SB203580 delivered systemically had no effect, indicating that the effect was mediated by local concentrations in the neural compartment. Evaluation of articular gene expression by quantitative real-time PCR showed that spinal p38 inhibition markedly decreased synovial interleukin-1 and -6 and matrix metalloproteinase (MMP3) gene expression. Activation of p38 required tumor necrosis factor alpha (TNFalpha) in the nervous system because IT etanercept (a TNF inhibitor) given during adjuvant arthritis blocked spinal p38 phosphorylation and reduced clinical signs of adjuvant arthritis.Conclusions: These data suggest that peripheral inflammation is sensed by the central nervous system (CNS), which subsequently activates stress-induced kinases in the spinal cord via a TNFalpha-dependent mechanism. Intracellular p38 MAP kinase signaling processes this information and profoundly modulates somatic inflammatory responses. Characterization of this mechanism could have clinical and basic research implications by supporting development of new treatments for arthritis and clarifying how the CNS regulates peripheral immune responses. [ABSTRACT FROM AUTHOR]