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Purpose: To evaluate the spatial distribution and signal intensity changes following spinal cord activation in patients with spinal cord injury.Methods: This study used spinal functional magnetic resonance imaging (fMRI) based on signal enhancement by extra-vascular water protons (SEEP) to assess elicited responses during subcutaneous electrical stimulation at the right elbow and right thumb in the cervical spinal cord.Results: Seven healthy volunteers and seven patients with cervical spinal cord injury (SCI) were included in this study. Significant functional activation was observed mainly in the right side of the spinal cord at the level of the C5-C6 cervical vertebra in both the axial and sagittal planes. A higher percentage of signal changes (4.66 ± 2.08 % in injured subjects vs. 2.78 ± 1.66 % in normal) and more average activation voxels (4.69 ± 2.59 in injured subjects vs. 2.56 ± 1.13 in normal subject) in axial plane at the C5-C6 cervical vertebra with a statistically significant difference. The same trends were observed in the sagittal plane with higher percentage of signal changes and more average activation voxels, though no statistically significant difference compared with the control group.Conclusions: Spinal SEEP fMRI is a powerful noninvasive method for the study of local neuronal activation in the human spinal cord, which may be of clinical value for evaluating the effectiveness of interventions aimed at promoting recovery of function using electrical stimulation. [ABSTRACT FROM AUTHOR]

Both diacylglycerol (DAG) and phosphatidic acid (PA) are important second messengers involved in signal transduction from many immune cell receptors and can be generated and metabolized through multiple mechanisms. Recent studies indicate that diacylglycerol kinases (DGKs), the enzymes that catalyze phosphorylation of DAG to produce PA, play critical roles in regulating the functions of multiple immune cell lineages. In T cells, two DGK isoforms, α and ζ, inhibit DAG-mediated signaling following T-cell receptor engagement and prevent T-cell hyperactivation. DGK α and ζ synergistically promote T-cell anergy and are critical for T-cell tolerence. In mast cells, DGKζ plays differential roles in their activation by promoting degranulation but attenuating cytokine production following engagement of the high affinity receptor for immunoglobulin E. In dendritic cells and macrophages, DGKζ positively regulates Toll-like receptor-induced proinflammatory cytokine production through its product PA and is critical for host defense against Toxoplama gondii infection. These studies demonstrate pivotal roles of DGKs in regulating immune cell function by acting both as signal terminator and initiator. [ABSTRACT FROM AUTHOR]

Presents information on a study which identified the three nuclear matrix attachment regions associated with the human T cell receptor delta gene using in vitro and in situ mapping approaches. Materials and methods of the study; Results and discussion.

Investigates the function of the blocking element alpha/delta 1 (BEAD-1) within the human T cell receptor (TCR) alpha/sigma segments. Enhancer-activity and enhancer-blocking in soft-agar colony forming assay adapted to the human T cell leukemia; Identification of enhancer-blocking activity; Cotransfection and cloning.

Invariant NKT (iNKT) cells, which express the invariant Vα14Jα18 TCR that recognizes lipid antigens, have the ability to rapidly respond to agonist stimulation, producing a variety of cytokines that can shape both innate and adaptive immunity. iNKT cells have been implicated in host defense against microbial infection, in anti-tumor immunity, and a multitude of diseases such as allergies, asthma, graft versus host disease, and obesity. Emerging evidence has demonstrated crucial role for mammalian target of rapamycin (mTOR) in immune cells, including iNKT. In this review we will discuss current understanding of how mTOR and its tight regulation control iNKT cell development, effector lineage differentiation, and function. [ABSTRACT FROM AUTHOR]

Study on corrole photosensitizers (PSs) for photodynamic therapy (PDT) has made remarkable progress. Targeted delivery of PSs is of great significance for enhancing therapeutic efficiency, decreasing the dosage, and reducing systemic toxicity during PDT. The development of PSs that can be specifically delivered to the subcellular organelle is still an attractive and challenging work. Herein, we synthesize a series of azide-modified corrole phosphorus and gallium complex PSs, in which phosphorus corrole 2-P could not only precisely target the endoplasmic reticulum (ER) with a Pearson correlation coefficient (PCC) up to 0.92 but also possesses the highest singlet oxygen quantum yields (Φ Δ = 0.75). This renders it remarkable PDT activity at a very low dosage (IC 50 = 23 nM) towards HepG2 tumor cell line while ablating solid tumors in vivo with excellent biosecurity. Furthermore, 2-P exhibits intense red fluorescence (Φ F = 0.25), outstanding photostability, and a large Stokes shift (190 nm), making it a promising fluorescent probe for ER. This study provides a clinically potential photosensitizer for cancer photodynamic therapy and a promising ER fluorescent probe for bioimaging. A new kind of azide-modified corrole gallium (III) and phosphorus(V) complexes were synthesized and used as PDT photosensitizers. The prepared corrole phosphorus complex (2-P) can precisely target the endoplasmic reticulum (ER) and in situ generate massive reactive oxygen species (ROS) under irradiation to induce tumor regression at a very low dosage. [Display omitted] • Novel azide-modified corrole complexes for PDT were synthesized and evaluated. • 2-P could specifically target to endoplasmic reticulum. • 2-P could generate ROS and evoke mitochondria dysfunction upon PDT. • 2-P -mediated PDT could effectively eliminate tumor in vitro and in vivo. • 2-P -mediated PDT caused cell apoptosis in the caspase pathway. [ABSTRACT FROM AUTHOR]

Mast cells play critical roles in allergic disorders and asthma. The importance of tuberous sclerosis complex 1/2-mammalian target of rapamycin (TSC1/2-mTOR) signaling in mast cells is unknown. Here, we report that TSC1 is a critical regulator for mTOR signaling in mast cells downstream of FceRI and c-Kit, and differentially controls mast cell degranulation and cytokine production. TSC1 -deficiency results in impaired mast cell degranulation, but enhanced cytokine production in vitro and in vivo after FceRI engagement. Furthermore, TSC1 is critical for mast cell survival through multiple pathways of apoptosis including the downregulation of p53, miR-34a, reactive oxygen species, and the up-regulation of Bcl-2. Together, these findings reveal that TSC1 is a critical regulator of mast cell activation and survival, suggesting the manipulation of the TSC1/2-mTOR pathway as a therapeutic strategy for mast cell-mediated diseases. [ABSTRACT FROM AUTHOR]

Purpose: The aim of our study was to propose a strategy based on indocyanine green (ICG) (SBI) to provide better clinical guidelines for transarterial chemoembolization (TACE) treatments for Barcelona clinic liver cancer (BCLC) stage C hepatocellular carcinoma (HCC) patients. Materials and Methods: From October 2005 to December 2012, 112 BCLC stage C HCC patients initially treated with TACE were investigated, randomly divided into a training cohort (n = 79) and validation cohort (n = 33). In training group, the patients were grouped based on their 15 minutes ICG retention rate (ICG R15), different chemo drugs and dose of lipidol in TACE. Overall survival (OS) and progression‐free survival (PFS) were analyzed in subgroups. Strategy based on ICG was built and verified in validation group. Results: For those patients with ICG R15 values >10%, the lipiodol ≤10 mL group showed better survival than the lipiodol >10 mL group. For those patients with ICG R15 values ≤10%, the group that received triple‐drug chemotherapy treatments with lipiodol diameter ratio values between 1 and 3 showed better survival than the other group. Patients who conformed with the SBI had better survival times than those who did not conform with the SBI, in both the training cohort (median OS 10.3 vs 5.1 months; P <.001; median PFS, 3.3 vs 2.1 months; P =.006) and the validation cohort (median OS 8.9 vs 7.1 months; P =.087; median PFS, 6.6 vs 2.3 months; P <.001). Conclusions: The SBI is suitable and may provide survival benefits for TACE treatments in BCLC stage C HCC patients. [ABSTRACT FROM AUTHOR]

NLRC3, a member of the NLR family, has been reported as a negative regulator of inflammatory signaling pathways in innate immune cells. However, the direct role of NLRC3 in modulation of CD4+ T-cell responses in infectious diseases has not been studied. In the present study, we showed that NLRC3 plays an intrinsic role by suppressing the CD4+ T cell phenotype in lung and spleen, including differentiation, activation, and proliferation. NLRC3 deficiency in CD4+ T cells enhanced the protective immune response against Mycobacterium tuberculosis infection. Finally, we demonstrated that NLRC3 deficiency promoted the activation, proliferation, and cytokine production of CD4+ T cells via negatively regulating the NF-κB and MEK-ERK signaling pathways. This study reveals a critical role of NLRC3 as a direct regulator of the adaptive immune response and its protective effects on immunity during M. tuberculosis infection. Our findings also suggested that NLRC3 serves as a potential target for therapeutic intervention against tuberculosis. [ABSTRACT FROM AUTHOR]

Vibrio vulnificus (V. vulnificus), a Gram-negative marine bacterium, can cause life-threatening primary septicemia, especially in patients with liver diseases. How V. vulnificus affects the liver and how it acts on macrophages are not well understood. In this report, we demonstrated that V. vulnificus infection causes a strong inflammatory response, marked expansion of liver-resident macrophages, and liver damage in mice. We demonstrated further that V. vulnificus activates mTOR in macrophages and inhibition of mTOR differentially regulates V. vulnificus induced inflammatory responses, suggesting the possibility of targeting mTOR as a strategy to modulate V. vulnificus induced inflammatory responses. [ABSTRACT FROM AUTHOR]

The purpose of this research was to use next generation sequencing to identify mutations in patients with primary immunodeficiency diseases whose pathogenic gene mutations had not been identified. Remarkably, four unrelated patients were found by next generation sequencing to have the same heterozygous mutation in an essential donor splice site of PIK3R1 (NM_181523.2:c.1425 + 1G > A) found in three prior reports. All four had the Hyper IgM syndrome, lymphadenopathy and short stature, and one also had SHORT syndrome. They were investigated with in vitro immune studies, RT-PCR, and immunoblotting studies of the mutation's effect on mTOR pathway signaling. All patients had very low percentages of memory B cells and class-switched memory B cells and reduced numbers of naïve CD4+ and CD8+ T cells. RT-PCR confirmed the presence of both an abnormal 273 base-pair (bp) size and a normal 399 bp size band in the patient and only the normal band was present in the parents. Following anti-CD40 stimulation, patient's EBV-B cells displayed higher levels of S6 phosphorylation (mTOR complex 1 dependent event), Akt phosphorylation at serine 473 (mTOR complex 2 dependent event), and Akt phosphorylation at threonine 308 (PI3K/PDK1 dependent event) than controls, suggesting elevated mTOR signaling downstream of CD40. These observations suggest that amino acids 435-474 in PIK3R1 are important for its stability and also its ability to restrain PI3K activity. Deletion of Exon 11 leads to constitutive activation of PI3K signaling. This is the first report of this mutation and immunologic abnormalities in SHORT syndrome. [ABSTRACT FROM AUTHOR]

Thymus is crucial for generation of a diverse repertoire of T cells essential for adaptive immunity. Although thymic epithelial cells (TECs) are crucial for thymopoiesis and T cell generation, how TEC development and function are controlled is poorly understood. We report here that mTOR complex 1 (mTORC1) in TECs plays critical roles in thymopoiesis and thymus function. Acute deletion of mTORC1 in adult mice caused severe thymic involution. TEC-specific deficiency of mTORC1 (mTORC1KO) impaired TEC maturation and function such as decreased expression of thymotropic chemokines, decreased medullary TEC to cortical TEC ratios, and altered thymic architecture, leading to severe thymic atrophy, reduced recruitment of early thymic progenitors, and impaired development of virtually all T-cell lineages. Strikingly, temporal control of IL-17-producing γδT (γδT17) cell differentiation and TCRVγ/δ recombination in fetal thymus is lost in mTORC1KO thymus, leading to elevated γδT17 differentiation and rearranging of fetal specific TCRVγ/δ in adulthood. Thus, mTORC1 is central for TEC development/function and establishment of thymic environment for proper T cell development, and modulating mTORC1 activity can be a strategy for preventing thymic involution/atrophy. [ABSTRACT FROM AUTHOR]

Accumulating evidence indicates that the tuberous sclerosis complex 1 (TSC1), a tumor suppressor that acts by inhibiting mTOR signaling, plays an important role in the immune system. We report here that TSC1 differentially regulates mTOR complex 1 (mTORC1) and mTORC2/Akt signaling in B cells. TSC1 deficiency results in the accumulation of transitional-1 (T1) B cells and progressive losses of B cells as they mature beyond the T1 stage. Moreover, TSC1KO mice exhibit a mild defect in the serum antibody responses or rate of Ig class-switch recombination after immunization with a T-cell-dependent antigen. In contrast to a previous report, we demonstrate that both constitutive Peyer’s patch germinal centers (GCs) and immunization-induced splenic GCs are unimpaired in TSC1-deficient (TSC1KO) mice and that the ratio of GC B cells to total B cells is comparable in WT and TSC1KO mice. Together, our data demonstrate that TSC1 plays important roles for B cell development, but it is dispensable for GC formation and serum antibody responses. [ABSTRACT FROM AUTHOR]

The engagement of the T cell receptor (TCR) induces the generation of diacylglycerol (DAG), an important second messenger activating both the Ras/Erk and PKCθ/NFκB pathways. DAG kinases (DGKs) participate in the metabolism of DAG by converting it to phosphatidic acid. DGKζ has been demonstrated to be able to inhibit DAG signaling following TCR engagement. Deficiency of DGKζ increases the sensitivity of T cells to TCR stimulation, resulting in enhanced T cell activation ex vivo and in vivo. However, the mechanisms that control DGKζ expression are poorly understood. Here we demonstrate that DGKζ mRNA is a direct target of a cellular microRNA miR-34a. The DGKζ transcript is decreased, whereas the primary miR-34a is upregulated upon TCR stimulation. Ectopic miR-34a expression suppresses DGKζ protein expression through the seed match binding to both the 3' untranslated region and coding region of DGKζ mRNA, leading to increased ERK1/2 phosphorylation and surface expression of the T cell activation marker CD69 following TCR cross-linking. In contrast, overexpression of a miR-34a competitive inhibitor increases DGKζ expression and suppresses TCR-mediated T cell activation. Together, our data demonstrate that miR-34a is a negative regulator for DGKζ and may play an important role in regulating T cell activation. [ABSTRACT FROM AUTHOR]

T cell development and activation are usually accompanied by expansion and production of numerous proteins that require active translation. The eukaryotic translation initiation factor 4E (eIF4E) binds to the 5' cap structure of mRNA and is critical for cap-dependent translational initiation. It has been hypothesized that MAPK-interacting kinase 1 and 2 (Mnkl/2) promote cap-dependent translation by phosphorylating eIF4E at serine 209 (S209). Pharmacologic studies using inhibitors have suggested that Mnkl/2 have important roles in T cells. However, genetic evidence supporting such conclusions is lacking. Moreover, the signaling pathways that regulate Mnkl/2 in T cells remain unclear. We demonstrate that TCR engagement activates Mnkl/2 in primary T cells. Such activation is dependent on Ras-Erkl/2 signaling and is inhibited by diacylglycerol kinases α and ξ. Mnkl/2 double deficiency in mice abolishes TCR-induced eIF4E S209 phosphorylation, indicating their absolute requirement for eIF4E S209 phosphorylation. However, Mnkl/2 double deficiency does not affect the development of conventional αβ T cells, regulatory T cells, or NKT cells. Furthermore, T cell activation, in vivo primary and memory CD8 T cell responses to microbial infection, and NKT cell cytokine production were not obviously altered by Mnkl/2 deficiency. Although Mnkl/2 deficiency causes decreased IL-17 and IFN-ɣ production by CD4 T cells following immunization of mice with myelin oligodendrocyte glycoprotein peptide in complete Freund's adjuvant, correlating with milder experimental autoimmune encephalomyelitis scores, it does not affect Th cell differentiation in vitro. Together, these data suggest that Mnkl/2 has a minimal role in T cell development and activation but may regulate non-T cell lineages to control Thl and Thl7 differentiation in vivo. [ABSTRACT FROM AUTHOR]

Diacylglycerol kinase α (DGKα) regulates diacylglycerol levels, catalyzing its conversion into phosphatidic acid. The α isoform is central to immune response regulation; it downmodulates Ras-dependent pathways and is necessary for establishment of the unresponsive state termed anergy. DGKα functions are regulated in part at the transcriptional level although the mechanisms involved remain poorly understood. Here, we analyzed the 5′ end structure of the mouse DGKα gene and detected three binding sites for forkhead box O (FoxO) transcription factors, whose function was confirmed using luciferase reporter constructs. FoxO1 and FoxO3 bound to the 5′ regulatory region of DGKα in quiescent T cells, as well as after interleukin-2 (IL-2) withdrawal in activated T cells. FoxO binding to this region was lost after complete T cell activation or IL-2 addition, events that correlated with FoxO phosphorylation and a sustained decrease in DGKα gene expression. These data strongly support a role for FoxO proteins in promoting high DGKα levels and indicate a mechanism by which DGKα function is downregulated during productive T cell responses. Our study establishes a basis for a causal relationship between DGKα downregulation, IL-2, and anergy avoidance. [ABSTRACT FROM AUTHOR]

The mechanisms that control TLR-induced responses, including endotoxin tolerance, have been not well understood. The tuberous sclerosis complex 1 (TSCl) is a tumor suppressor that inhibits the mammalian target of rapamycin (mTOR). We show in this study that deficiency of TSCl results in enhanced activation of not only mTOR complex 1 (mTORCl), but also JNKl/2, following LPS stimulation in macrophages. TSCI-deficient macrophages produce elevated proinflammatory cytokines and NO in response to multiple TLR Iigands. Such enhanced TLR-induced responses can be inhibited by reducing mTORCl and JNKl/2 activities with chemical inhibitors or small hairpin RNA, suggesting that TSCl negatively controls TLR responses through both mTORCl and JNKl/2. The impact of TSCl deficiency appeared not limited to TLRs, as NOD- and RIG-I/MDA-5-induced innate responses were also altered in TSCl-deficient macrophages. Furthermore, TSCl deficiency appears to cause impaired induction of endotoxin tolerance in vitro and in vivo, which is correlated with increased JNKl/2 activation and can be reversed by JNKl/2 inhibition. Our results reveal a critical role of TSCl in regulating innate immunity by negative control of mTORCl and JNKl/2 activation. [ABSTRACT FROM AUTHOR]

Background. Peanut allergy is driven by peanut-specific Th2 cells. Ara h 2, a peanut 2S albumin, is one of the major peanut allergens. Methods. An Ara h 2-specific T cell line was generated from peanut sensitised C3H/HeJ mice and used to analyse allergen-induced cytokine secretion and activation of signalling molecules. Results. Peanut stimulated splenocytes from peanut sensitised mice had strong proliferation responses and highly elevated IL-4 secretion. The Ara h 2-specific T cells generated from sensitised mice were mainly CD4+ T helper cells with a Th2 cytokine profile. The expression of CD154 on the surface of these T cell clones was detected following Ara h 2 stimulation. Ara h 2 stimulation induced phosphorylation of ZAP-70 and Erk1/2 in the T cells. Conclusions. CD154 is a useful marker for identifying activated, allergen-specific T cells. The Ras-Erk mitogen-activated protein kinase pathway is involved in the activation of Ara h 2-specific Th2 cells. [ABSTRACT FROM AUTHOR]

• The electrochemical chloride removal efficiency is affected by the stirrup. • The stirrup has both shielding and accelerating effects on chloride ion migration. • The influence of the stirrup decreases as the distance from the stirrup increases. • The chloride removal efficiency is the highest in the section with the stirrup. • A numerical model is proposed that can accurately predict treatment efficiency. Chloride ion is one of the most important factors leading to the corrosion of steel bar embedded in marine concrete structures. The chloride induced corrosion is also considered harmful to the service life and durability of structures. Electrochemical chloride removal (ECR) is a nondestructive method, which can be used to terminate the corrosion and prolong the service life of concrete structures to minimize the economic and environmental costs caused by structural reconstruction. The presence of stirrup embedded in concrete affects the potential distribution in the concrete structure, and further affect the transport of chloride ions during the ECR treatment. In this study, a theoretical model of a concrete structure containing stirrups was established to investigate the effect of the stirrups on the transport of chloride ions during ECR. Based on both modelling and experimental results, the stirrup has two-fold effects on the transport of chloride ions in the local region close to the concrete section with the stirrup. On one hand, the shielding effect makes the region enclosed by the stirrup become an equipotential body, and hinders the migration of the chloride ions; on the other hand, the accelerating effect caused by the increasing cathodic area due to the existence of stirrup, increases chloride ion migration speed. [ABSTRACT FROM AUTHOR]

NOD‐like receptor (NLR) family CARD domain containing 3 (NLRC3), an intracellular member of NLR family, is a negative regulator of inflammatory signaling pathways in innate and adaptive immune cells. Previous reports have shown that NLRC3 is expressed in dendritic cells (DCs). However, the role of NLRC3 in DC activation and immunogenicity is unclear. In the present study, we find that NLRC3 attenuates the antigen‐presenting function of DCs and their ability to activate and polarize CD4+ T cells into Th1 and Th17 subsets. Loss of NLRC3 promotes pathogenic Th1 and Th17 responses and enhanced experimental autoimmune encephalomyelitis (EAE) development. NLRC3 negatively regulates the antigen‐presenting function of DCs via p38 signaling pathway. Vaccination with NLRC3‐overexpressed DCs reduces EAE progression. Our findings support that NLRC3 serves as a potential target for treating adaptive immune responses driving multiple sclerosis and other autoimmune disorders. Synopsis: The innate immune sensor NLRC3 negatively regulates dendritic cell activation to affect Th1 and Th17 cell differentiation and experimental autoimmune encephalomyelitis. NLRC3 attenuates the antigen‐presenting function of DCs and their ability to activate and polarize CD4+ T cells into Th1 and Th17 subsets.Loss of NLRC3 promotes pathogenic Th1 and Th17 responses and enhanced EAE development.NLRC3 negatively regulates the antigen‐presenting function of DCs via p38 signaling pathway. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "iNKT cells require TSC1 for terminal maturation and effector lineage fate decisions" that appeared in a previous issue .

Invariant natural killer T (iNKT) cells play important roles in bridging innate and adaptive immunity via rapidly producing a variety of cytokines. A small subset of iNKT cells produces IL-17 and is generated in the thymus during iNKT-cell ontogeny. The mechanisms that control the development of these IL-17-producing iNKT-17 cells (iNKT-17) are still not well defined. Diacylglycerol kinase ζ (DGKζ) belongs to a family of enzymes that catalyze the phosphorylation and conversion of diacylglycerol to phosphatidic acid, two important second messengers involved in signaling from numerous receptors. We report here that DGKζ plays an important role in iNKT-17 development. A deficiency of DGKζ in mice causes a significant reduction of iNKT-17 cells, which is correlated with decreased RORγt and IL-23 receptor expression. Interestingly, iNKT-17 defects caused by DGKζ deficiency can be corrected in chimeric mice reconstituted with mixed wild-type and DGKζ-deficient bone marrow cells. Taken together, our data identify DGKζ as an important regulator of iNKT-17 development through iNKT-cell extrinsic mechanisms. [ABSTRACT FROM AUTHOR]