SOD2 promotes the immunosuppressive function of mesenchymal stem cells at the expense of adipocyte differentiation.

The potent immunomodulatory function of mesenchymal stem/stromal cells (MSCs) elicited by proinflammatory cytokines IFN-γ and TNF-α (IT) is critical to resolve inflammation and promote tissue repair. However, little is known about how the immunomodulatory capability of MSCs is related to their differentiation competency in the inflammatory microenvironment. In this study, we demonstrate that the adipocyte differentiation and immunomodulatory function of human adipose tissue-derived MSCs (MSC(AD)s) are mutually exclusive. Mitochondrial reactive oxygen species (mtROS), which promote adipocyte differentiation, were decreased in MSC(AD)s due to IT-induced upregulation of superoxide dismutase 2 (SOD2). Furthermore, knockdown of SOD2 led to enhanced adipogenic differentiation but reduced immunosuppression capability of MSC(AD)s. Interestingly, the adipogenic differentiation was associated with increased mitochondrial biogenesis and upregulation of peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PPARGC1A/PGC-1α) expression. IT inhibited PGC-1α expression and decreased mitochondrial mass but promoted glycolysis in an SOD2-dependent manner. MSC(AD)s lacking SOD2 were compromised in their therapeutic efficacy in DSS-induced colitis in mice. Taken together, these findings indicate that the adipogenic differentiation and immunomodulation of MSC(AD)s may compete for resources in fulfilling the respective biosynthetic needs. Blocking of adipogenic differentiation by mitochondrial antioxidant may represent a novel strategy to enhance the immunosuppressive activity of MSCs in the inflammatory microenvironment.

Regulation of gut bacteria in silkworm (Bombyx mori) after exposure to endogenous cadmium-polluted mulberry leaves.

Soil cadmium (Cd) pollution presents a severe pollution burden to flora and fauna due to its non-degradability and transferability. The Cd in the soil is stressing the silkworm (Bombyx mori) out through a soil-mulberry-silkworm system. The gut microbiota of B.mori are reported to shape host health. However, earlier research had not reported the effect of endogenous Cd-polluted mulberry leaves on the gut microbiota of B.mori. In the current research, we compared the phyllosphere bacteria of endogenous Cd-polluted mulberry leaves at different concentrations. The investigation of the gut bacteria of B.mori fed with the mulberry leaves was done to evaluate the impact of endogenous Cd- polluted mulberry leaves on the gut bacteria of the silkworm. The results revealed a dramatic change in the gut bacteria of B.mori whereas, the changes in the phyllosphere bacteria of mulberry leaves in response to an increased Cd concentration were insignificant. It also increased the α-diversity and altered the gut bacterial community structure of B. mori. A significant change in the abundance of dominant phyla of gut bacteria of B.mori was recorded. At the genus level, the abundance of Enterococcus, Brachybacterium and Brevibacterium group related to disease resistance, and the abundance of Sphingomonas, Glutamicibacter and Thermus related to metal detoxification was significantly increased after Cd exposure. Meanwhile, there was a significant decrease in the abundance of the pathogenic bacteria Serratia and Enterobacter. The results demonstrated that endogenous Cd-polluted mulberry leaves caused perturbations in the gut bacterial composition of B.mori, which may driven by Cd content rather than phyllosphere bacteria. A significant variation in the specific bacterial community indicated the adaptation of B. mori gut for its role in heavy metal detoxification and immune function regulation. The results of this study help to understand the bacterial community associated with endogenous Cd-polluted resistance in the gut of B.mori, which proves to be a novel addition in describing its response in activating the detoxification mechanism and promoting its growth and development. This research work will help to explore the other mechanisms and microbiota associated with the adaptations to mitigate the Cd pollution problems.

Characterization of galacto-oligosaccharides using high-performance anion exchange chromatography-tandem mass spectrometry.

The analysis of complex oligosaccharide mixtures remains a challenge in the field of analytical chemistry. In this work, two commercial galacto-oligosaccharides samples were characterized using high-performance anion exchange chromatography coupled to mass spectrometry. The isomeric oligosaccharides were resolved with high resolution. The structures of the individual isomers with a degree of polymerization up to 6 were analyzed using targeted selected ion monitoring with data-dependent tandem mass spectrometry, with additional in-source collision-induced dissociation.

Nanovolume Gas-Free Hydroxide Eluent Generator for Open Tubular Ion Chromatography.

A gas-free KOH eluent generator (EG) with 210 nL of internal volume is described. It utilizes a two-membrane configuration where there is a single CEM layer on one side and a single BPM layer on the other side for use in open tubular ion chromatography systems with typical back pressures < 50 psi. At a flow rate of ∼190 nL/min, the 10-90% gradient rise time is 3.5 min. The device shows good linearity between applied current and concentration of KOH generated, which is stable over extended periods. The overall system reproducibility (that includes contributions from any changes in flow rate), as judged by the relative standard deviation (RSD) of the retention times of individual separated ions in repeat measurements (n = 6), ranged from <0.5% for isocratic to <1.2% for gradient elution schemes. Perceptible current flow and KOH production in the BPM-based EG begins at subelectrolytic applied voltages, prompting us to look more closely at exact field strength necessary for field-enhanced dissociation of water. An increase in the specific conductance of pure water is noticeable by a field strength of 105 V/m.

Dual Electrolytic Eluent Generation for Oligosaccharides Analysis Using High-Performance Anion-Exchange Chromatography.

The research on oligosaccharides is growing and gaining in importance at a rapid pace. The efforts to understand their bioactivity and to develop new products based on oligosaccharides in biotherapeutics and food industry require effective and reliable tools for analysis of oligosaccharides. Here we present a dual electrolytic eluent generation platform for the analysis of oligosaccharides by high-performance anion-exchange liquid chromatography (HPAE) in both analytical and capillary column formats. The system consists of one eluent generator producing methanesulfonic acid (MSA) connected in series with a second eluent generator producing potassium hydroxide (KOH). Through manipulating the concentration output of both eluent generators, chromatographic performance comparable to that obtained using the conventional sodium acetate/sodium hydroxide (NaOAc/NaOH) eluents is achieved using the electrolytically generated potassium methanesulfonate/potassium hydroxide (KMSA/KOH) eluent. This platform utilizes deionized water as the only carrier stream through a single isocratic pump, overcomes the various drawbacks associated with manually prepared NaOAc/NaOH eluents, and offers an easy to use, simplified operation solution for oligosaccharides profiling with increased precision and accuracy.

[Effects of soluble programmed death ligand 1 on regulating the proliferation of T lymphocytes and its mechanism].

OBJECTIVE: To explore the effects of soluble programmed death ligand 1 (sPD-L1) on the proliferation of T lymphocytes and its mechanism. METHODS: T lymphocytes were isolated from healthy human peripheral blood and activated by phytohemagglutinin (PHA). The experiment had group A: resting T lymphocytes, group B: activated T lymphocytes, group C: activated T lymphocytes+sPD-L1Ig, group D: activated T lymphocytes+sPD-L1Ig+membrance-bound immunoglobulin (mIgG) and group E: activated T lymphocytes+sPD-L1Ig+anti-PD-L1 antibody (2H11). The absorbance value (A) of T lymphocytes in each group was measured by cell counting kit (CCK-8). The cell cycle and apoptosis of T lymphocytes induced by sPD-L1 were measured by flow cytometry. And the phosphorylation level of programmed death 1 (PD-1) signaling motif tyrosine was measured by Western blot. Furthermore, the amounts of signal adaptor molecule Src homology 2 domain-containing tyrosine phosphatase (SHP)-1 and SHP-2 were quantified by immunoprecipitation. And the exciting mechanism of sPD-L1 was explored for PD-1 inhibitory signals. RESULTS: CCK-8 study showed that A values in each group were 0.42 ± 0.03, 1.20 ± 0.06, 0.87 ± 0.05, 0.78 ± 0.05 and 1.11 ± 0.09 respectively when the concentration of sPD-L1Ig was 250 ng/ml. The proliferation of T lymphocytes in group C significantly decreased compared with group B (t = 3.946, P = 0.017) while group E significantly increased compared with group D (t = 3.139, P = 0.035). The percentage of cell number in G1 phase of the above-mentioned 5 groups were (94.49 ± 0.50)%, (79.22 ± 0.50)%, (89.62 ± 0.33)%, (92.89 ± 0.80)% and (87.94 ± 0.87)% respectively and group C significantly increased compared with group B (t = 17.310, P < 0.001). The apoptotic rate of the above-mentioned five groups were (35.77 ± 1.82)%, (35.20 ± 2.70)%, (62.77 ± 0.24)%, (64.47 ± 0.44)% and (36.80 ± 3.53)% respectively. And apoptotic rate in group C significantly increased compared with group B (t = 10.160, P = 0.001) while group E significantly decreased compared with group D (t = 7.790, P = 0.002). The expressions of SHP-1 and SHP-2 showed no inter-group difference (all P > 0.05). However, the expressions of p-SHP-1 and p-SHP-2 in group C was higher than those in group B (t = 10.790, P < 0.001; t = 13.051, P < 0.001) while the expression of p-SHP-1 decreased in group E compared with group D (t = 3.361, P = 0.028). CONCLUSIONS: Soluble PD-L1 can effectively inhibit the proliferation of T lymphocytes. The phosphorylation of SHP-1 and SHP-2 contributes to the inhibitory signaling of PD-1/sPD-L1 pathway. And anti-PD-L1 blocking antibody may partially restore the proliferation of T lymphocytes through a down-regulated expression of p-SHP-1..

[Level of soluble programmed death ligand 1 in pleural effusion and peripheral blood of patients with tuberculous pleural effusion and its clinical implications].

OBJECTIVE: To explore the level of soluble programmed death ligand 1 (sPD-L1) in pleural effusion and peripheral blood of patients with tuberculous pleural effusion (TPE) and elucidate its clinical implications. METHODS: Patients with newly diagnosed pleural effusion at the Second Affiliated Hospital of Soochow University from June 2012 to March 2013 were enrolled and divided into 3 groups of TPE, malignant pleural effusion (MPE) and non-tuberculous non-malignant pleural effusion (non-TPE non-MPE) according to the nature of pleural effusion. The level of sPD-L1 in pleural effusion and peripheral blood was analyzed by enzyme linked immunosorbent assay (ELISA) kit. Flow cytometry was used to detect the changes of immune cell subsets in pleural effusion. And the gene expressions of programmed death ligand 1 (PD-L1) and matrix metalloproteinase-3 (MMP-3) were detected in different effusions by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: A total of 77 newly diagnosed patients with pleural effusion were enrolled, 24 patients with TPE, 39 patients with MPE, 14 patients with non-TPE non-MPE. The level of sPD-L1 in TPE was higher than that in MPE and non-TPE non-MPE (4.2 (2.6-6.3), 1.4 (0.8-2.1), 1.8 (1.2-2.6) µg/L, P < 0.001). No significant difference existed in the levels of sPD-L1 in peripheral blood samples (P = 0.811). The average content of sPD-L1 in pleural effusion in all patients was statistically higher than that in peripheral blood (2.0 (1.4-3.7), 1.5 (1.0-2.0) µg/L, P = 0.004). The proportion of CD8 subset, PD-L1 on CD14(+) monocytes and the mRNA level of PD-L1, MMP-3 in TPE were higher than in MPE and non-TPE non-MPE (P = 0.001, P < 0.001, P < 0.001), and the mRNA level of PD-L1 in TPE was positively correlated with the level of MMP-3 (r = 0.887, P < 0.001). Receiver operating characteristic (ROC) curve analysis showed that sPD-L1 had a sensitivity of 82.6%, a specificity of 83.8% and an area under curve (AUC) of 0.854 for differential diagnosis of TPE from other conditions. Combinations of sPD-L1, PD-L1 on CD14(+) monocytes and adenosine deaminase (ADA) measurements further increased the sensitivity up to 91.3%, specificity up to 89.2% and AUC up to 0.989. CONCLUSION: The elevated expression of sPD-L1 in tuberculous pleural effusion may aid the diagnosis of TPE.

[Effect of cisplatin alone or combined with monoclonal anti-programmed death ligand-1 antibody on lung adenocarcinoma cell line SPCA-1 and T lymphocytes].

OBJECTIVE: To observe the effect of cisplatin alone or combined with anti-programmed death ligand 1 monoclonal antibody (anti-PD-L1 mAb) on the co-culture system of lung adenocarcinoma SPCA-1 cells and T lymphocytes, and therefore to study the immunotherapeutic effect of anti-PD-L1 mAb on lung cancer. METHODS: Human adenocarcinoma SPCA-1 cell line was selected by flow cytometry (FCM) due to its high expression of membranous programmed death ligand-1 (PD-L1). The concentration of cisplatin was determined by CCK-8 method depending on the inhibition rate of SPCA-1 cell, which was set to less-than-or-equal-to 20% (IC20). After treatment with different concentrations of cisplatin, cell proliferation (A value) of SPCA-1 cells and T lymphocytes were detected by CCK-8 method and cell cycle of SPCA-1 cells and cell apoptosis of T lymphocytes were analyzed using PI staining. Treated with different concentrations of cisplatin alone or in combination with anti-PD-L1, T lymphocyte proliferation in co-culture system was determined by CCK-8 method, and cytokines such as IFN (interferon)-γ, IL-2, IL-10 and TNF-α were detected with enzyme linked immunosorbent assay (ELISA) method. RESULTS: The IC20 of cisplatin on SPCA-1 cells was ≤ 0.78 mg/L. The proliferation of SPCA-1 cells were inhibited with different concentrations of cisplatin in a concentration-dependent manner (0.78∼12.5 mg/L) (P < 0.001). Compared with the group treated with high-dose of cisplatin (12.5 mg/L), the proliferation of T lymphocytes treated with low-dose of cisplatin (0.78 mg/L) was higher (t = 3.508, P < 0.05) and the number of late apoptotic and dead T lymphocytes in the co-culture system was reduced (t = 17.55, P < 0.001). Compared with the group of co-culture system, cisplatin (0.78 mg/L) combined with anti-PD-L1 (1.5 mg/L) significantly enhanced the proliferation of T lymphocytes in the co-culture system (t = 4.419, P < 0.01). Also, the levels of T helper cell type-1 (Th1) cytokines such as IFN-γ, IL-2 and TNF-α were up-regulated (t = 25.79-55.15, P < 0.01) and the T helper cell type-2 (Th2) cytokine IL-10 was down-regulated (t = 18.38, P < 0.01). CONCLUSION: Low-dose of cisplatin combined with anti-PD-L1 could effectively promote the proliferation of T lymphocytes in the microenvironment and increase the secretion of Th1 type cytokines. This may reduce the toxic effect of high-dose antineoplastic agents on immune cells and help eradication of tumor cells.

The first mitogenomic phylogenetic framework of Dorcus sensu lato (Coleoptera: Lucanidae), with an emphasis on generic taxonomy in Eastern Asia.

BACKGROUND: Dorcus stag beetles in broad sense are one of the most diverse group in Lucanidae and important saproxylic insects playing a crucial role in nutrient recycling and forest biomonitoring. However, the dazzling morphological differentiations have caused numerous systematic confusion within the big genus, especially the puzzlingly generic taxonomy. So far, there is lack of molecular phylogenetic study to address the chaotic situation. In this study, we undertook mitochondrial genome sequencing of 42 representative species including 18 newly-sequenced ones from Eastern Asia and reconstructed the phylogenetic framework of stag beetles in Dorcus sensu lato for the first time. RESULTS: The mitogenome datasets of Dorcus species have indicated the variable mitogenomic lengths ranged from 15,785 to 19,813 bp. Each mitogenome contained 13 PCGs, 2 rRNAs, 22 tRNAs, and a control region, and all PCGs were under strong purifying selection (Ka/Ks < 1). Notably, we have identified the presence of a substantial intergenic spacer (IGS) between the trnAser (UCN) and NAD1 genes, with varying lengths ranging from 129 bp (in D. hansi) to 158 bp (in D. tityus). The mitogenomic phylogenetic analysis of 42 species showed that Eastern Asia Dorcus was monophyletic, and divided into eight clades with significant genetic distance. Four of them, Clade VIII, VII, VI and I are clustered by the representative species of Serrognathus Motschulsky, Kirchnerius Schenk, Falcicornis Séguy and Dorcus s.s. respectively, which supported their fully generic positions as the previous morphological study presented. The topology also showed the remaining clades were distinctly separated from the species of Dorcus sensu lato, which implied that each of them might demonstrate independent generic status. The Linnaeus nomenclatures were suggested as Eurydorcus Didier stat. res., Eurytrachellelus Didier stat. res., Hemisodorcus Thomson stat. res. and Velutinodorcus Maes stat. res. For Clade V, IV, III and II respectively. CONCLUSION: This study recognized the monophyly of Dorcus stag beetles and provided a framework for the molecular phylogeny of this group for the first time. The newly generated mitogenomic data serves as a valuable resource for future investigations on lucanid beetles. The generic relationship would facilitate the systematics of Dorcus stag beetles and thus be useful for exploring their evolutionary, ecological, and conservation aspects.

PML-mediated nuclear loosening permits immunomodulation of mesenchymal stem/stromal cells under inflammatory conditions.

Nuclear configuration plays a critical role in the compartmentalization of euchromatin and heterochromatin and the epigenetic regulation of gene expression. Under stimulation by inflammatory cytokines IFN-γ and TNF-α, human mesenchymal stromal cells (hMSCs) acquire a potent immunomodulatory function enabled by drastic induction of various effector genes, with some upregulated several magnitudes. However, whether the transcriptional upregulation of the immunomodulatory genes in hMSCs exposed to inflammatory cytokines is associated with genome-wide nuclear reconfiguration has not been explored. Here, we demonstrate that hMSCs undergo remarkable nuclear reconfiguration characterized by an enlargement of the nucleus, downregulation of LMNB1 and LMNA/C, decondensation of heterochromatin, and derepression of repetitive DNA. Interestingly, promyelocytic leukaemia-nuclear bodies (PML-NBs) were found to mediate the nuclear reconfiguration of hMSCs triggered by the inflammatory cytokines. Significantly, when PML was depleted, the immunomodulatory function of hMSCs conferred by cytokines was compromised, as reflected by the attenuated expression of effector molecules in hMSCs and their failure to block infiltration of immune cells to lipopolysaccharide (LPS)-induced acute lung injury. Our results indicate that the immunomodulatory function of hMSCs conferred by inflammatory cytokines requires PML-mediated chromatin loosening.

Targeting the glucocorticoid receptor-CCR8 axis mediated bone marrow T cell sequestration enhances infiltration of anti-tumor T cells in intracranial cancers.

Brain tumors such as glioblastomas are resistant to immune checkpoint blockade therapy, largely due to limited T cell infiltration in the tumors. Here, we show that mice bearing intracranial tumors exhibit systemic immunosuppression and T cell sequestration in bone marrow, leading to reduced T cell infiltration in brain tumors. Elevated plasma corticosterone drives the T cell sequestration via glucocorticoid receptors in tumor-bearing mice. Immunosuppression mediated by glucocorticoid-induced T cell dynamics and the subsequent tumor growth promotion can be abrogated by adrenalectomy, the administration of glucocorticoid activation inhibitors or glucocorticoid receptor antagonists, and in mice with T cell-specific deletion of glucocorticoid receptor. CCR8 expression in T cells is increased in tumor-bearing mice in a glucocorticoid receptor-dependent manner. Additionally, chemokines CCL1 and CCL8, the ligands for CCR8, are highly expressed in bone marrow immune cells in tumor-bearing mice to recruit T cells. These findings suggested that brain tumor-induced glucocorticoid surge and CCR8 upregulation in T cells lead to T cell sequestration in bone marrow, impairing the anti-tumor immune response. Targeting the glucocorticoid receptor-CCR8 axis may offer a promising immunotherapeutic approach for the treatment of intracranial tumors.

Enhancement of membrane B7-H3 costimulatory molecule but reduction of its soluble form in multiple sclerosis.

PURPOSE: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system mediated by T cells. B7-H3 plays a diverse role in regulating T cell responses. However, its expression and clinical significance in MS are not well known. This study analyzed the expression of membrane B7-H3 (mB7-H3) and levels of soluble B7-H3 (sB7-H3) in MS patients to determine its clinical significance. METHODS: Peripheral blood (PB) or cerebrospinal fluid (CSF) samples from healthy controls, other noninflammatory neurological disorders, viral encephalitis, and MS patients were collected. Expression of mB7-H3 on immune cells was detected by flow cytometry. Levels of sB7-H3 in serum or CSF samples were measured by ELISA. RESULTS: mB7-H3 expression was up-regulated in CSF from MS patients compared to PB (p<0.001). However, serum or CSF levels of sB7-H3 in MS patients were significantly lower than those in controls (p<0.05). Relapsing-MS patients had higher CSF mB7-H3 expression than the remitting subgroup. Relapsing-MS patients had decreased serum and CSF sB7-H3 levels compared with the remitting subgroup. Neurological deficits showed negative correlations with serum or CSF sB7-H3 levels, but a positive correlation with CSF mB7-H3 expression. Methylprednisolone therapy significantly elevated sB7-H3 levels and reduced mB7-H3 expression compared with pre-therapy levels. sB7-H3 levels did not correlate with mB7-H3 expression. CONCLUSIONS: We demonstrated enhanced mB7-H3 expression and reduced sB7-H3 levels in MS patients which correlated with the clinical characteristics of MS patients. These results suggest that B7-H3 may be a promising biomarker and associated with the pathogenesis of MS.

Bladder cancer determination via two urinary metabolites: a biomarker pattern approach.

The purpose of this study was to use metabonomic profiling to identify a potential specific biomarker pattern in urine as a noninvasive bladder cancer (BC) detection strategy. A liquid chromatography-mass spectrometry based method, which utilized both reversed phase liquid chromatography and hydrophilic interaction chromatography separations, was performed, followed by multivariate data analysis to discriminate the global urine profiles of 27 BC patients and 32 healthy controls. Data from both columns were combined, and this combination proved to be effective and reliable for partial least squares-discriminant analysis. Following a critical selection criterion, several metabolites showing significant differences in expression levels were detected. Receiver operating characteristic analysis was used for the evaluation of potential biomarkers. Carnitine C9:1 and component I, were combined as a biomarker pattern, with a sensitivity and specificity up to 92.6% and 96.9%, respectively, for all patients and 90.5% and 96.9%, respectively for low-grade BC patients. Metabolic pathways of component I and carnitine C9:1 are discussed. These results indicate that metabonomics is a practicable tool for BC diagnosis given its high efficacy and economization. The combined biomarker pattern showed better performance than single metabolite in discriminating bladder cancer patients, especially low-grade BC patients, from healthy controls.

[Effect of soluble PD-L1 released by lung cancer cells in regulating the function of T lymphocytes].

OBJECTIVE: To explore the expression of soluble programmed death ligand-1 on lung cancer cells and to clarify its biological function through PD-1/PD-L1 pathway in regulating the function of T lymphocytes. METHODS: Labeled monoclonal antibody and flow cytometry were used to analyze the expression of PD-L1 and its receptor PD-l on lung cancer cells and human T lymphocytes, respectively. The level of sPD-L1 in the supernatant of lung cancer cells was determined with an ELISA kit. The inhibition of proliferation of T lymphocytes by mPD-L1 and sPD-L1 was studied using CCK-8 incorporation. RESULTS: Low or no expression [(16.08 ± 2.28)%] of PD-1 was found on resting T lymphocytes from human peripheral blood with flow cytometry, but up-regulated expression of PD-1 [(78.06 ± 7.21)%] was found on the surface of activated T lymphocytes. Soluble PD-L1 was found in supernatant of some lung cancer cell lines, such as H1299, HO8910, SPCA-1, H460, H446 cells, with PD-L1 expressing on their cell surface [(78.34 ± 10.25)%, (68.17 ± 11.56)%, (45.32 ± 7.98)%, (47.52 ± 9.62)% and (40.95 ± 8.56)%, respectively], but very low expression on A549 cells [(16.02 ± 6.28)%]. The level of mPD-L1 on H1299 cells was highest [(78.34 ± 10.25)%], compared with HO8910 cells (68.17 ± 11.56)%, SPCA-1 cells (45.32 ± 7.98)%, H446 cells (40.95 ± 8.56)%, and H460 cells (47.52 ± 9.62)%. At the same time, the sPD-L1 level on H1299 cells was low [(0.17 ± 0.01) ng/ml], compared with HO8910 cells (0.30 ± 0.03) ng/ml, SPCA-1cells (0.59 ± 0.03) ng/ml, H446 cells (0.34 ± 0.02) ng/ml, and H460 cells (0.57 ± 0.03) ng/ml, but not expressed on A549 cells. PD-L1 expressing H1299 cells inhibited the proliferation of T lymphocytes in the co-culture system. Supernatant of the cultured PD-L1(+) lung cancer cells also inhibited T cell proliferation. Anti-human PD-L1 blocking antibody could partly restore the proliferation capacity of T lymphocytes. CONCLUSIONS: Membrane-bound PD-L1 and soluble PD-L1 released from lung cancer cells can effectively inhibit the proliferation of T lymphocytes in mixed culture system and down-regulate cell-mediated immunity in vitro. This may lead to inactivation of tumor antigen-specific T cells and immune escape of lung cancer cells.

[Expression of PD-1/PD-L1 in peripheral blood mononuclear cells in lung cancer patients and its biological significance].

OBJECTIVE: To analyze the expression of co-stimulatory molecules PD-1/PD-L1 in peripheral blood mononuclear cells in lung cancer patients, and to explore its biological significance. METHODS: One hundred and thirty-three lung cancer patients, 25 lung infection patients and 23 healthy donors were enrolled in this study. 100 µl of whole blood from these subjects were collected. Multi-color immunofluorescence staining and flow cytometry were used to detect PD-1/PD-L1 expression. The results were statistically analyzed. RESULTS: The expression level of CD3⁺CD8⁺ T cells in the lung cancer patients was (38.83 ± 1.74)%, significantly lower than that in the control group [(43.25 ± 3.35)%, P < 0.05]. CD8⁺CD28⁺ T cell subset in the peripheral blood of lung cancer patients was (17.73 ± 1.21)% significantly lower than that of the healthy donors [(27.96 ± 2.72)%, P < 0.01]. The CD8⁺CD28⁻ T cell subset was (21.19 ± 1.92)% in the lung cancer patients, significantly higher than that of the healthy control group [(15.18 ± 2.93)%, P < 0.05]. The expression level of PD-1 on the surface of CD8⁺CD28⁺ T cells was (10.67 ± 1.12)% in the group of lung cancer patients, significantly higher than that of the control group [(5.32 ± 1.58)%, P < 0.01]. It was also found that the expression of PD-1 on CD8⁺CD28⁻ T cells was up-regulated in the group of lung cancer patients (7.46 ± 1.25)%, significantly higher than that of the healthy control group [(2.68+1.07)%, P < 0.01]. The expression level of PD-L1 on CD68⁺ cells in the lung cancer patients was (16.03 ± 2.06)%, significantly higher than that of the healthy control group [(9.32 ± 2.00)%, P < 0.05]. CONCLUSION: Up-regulation of PD-1/PD-L1 on peripheral blood cells in lung cancer patients negatively regulates the lymphocytes, inhibits the immune response for killing tumor cells, and promotes tumor development and immune escape.

Seasonal variation in soil algal community structure in different forest plantations in subtropic China.

Algae exert great impact on soil formation and biogeochemical cycling. However, there is no full understanding of the response of soil algal community structure to the seasonal fluctuations in temperature and moisture and changes of soil physicochemical properties across different forests. Here, based on 23S rRNA gene sequencing, we analyzed soil algal community structure in four different forest plantations in two seasons and examined soil physiochemical properties. The results showed the significantly seasonal variation in soil algal community structure, with the higher overall diversity in summer than in winter. In addition, there existed significant correlations between soil algae (species composition, relative abundance, diversity index) and physicochemical properties (pH, total phosphorus, organic matter and nitrate nitrogen), suggesting that edaphic characteristics are also largely responsible for the variation in soil algal community. Nevertheless, the seasonal variation in algal community structure was greater than the variation across different forest plantations. This suggest temperature and moisture are more important than soil physicochemical properties in determining soil algal community structure. The findings of the present study enhance our understanding of the algal communities in forest ecosystems and are of great significance for the management and protection of algal ecosystem.

Preparation of Yb-Sb co-doped Ti/SnO2 electrode for electrocatalytic degradation of sulfamethoxazole (SMX).

To efficiently break down residual sulfonamide antibiotics in environmental water, Yb-Sb co-doped Ti/SnO2 electrodes were fabricated using a solvothermal method. The effect of different amounts of Yb doping on the properties of the electrodes was studied. When the atom ratio of Sn: Yb is 100 : 7.5 in the preparation, the as-obtained coral-like electrodes (denoted as Yb 7.5%) possessed the smallest diameter of spherical particles on the surfaces, to result in the denser surface, highest electrocatalytic activity and smallest resistance of the electrode. As anode for electrocatalytic degradation of sulfamethoxazole, the Yb 7.5% electrode showed a degradation rate of 92% in 90 min, which was much higher than that of Yb 0% electrode (62.7% degradation rate). The electrocatalytic degradation of sulfamethoxazole was investigated with varying current densities and initial concentrations. Results indicated that the degradation process followed pseudo-first-order kinetics, and the degradation rate constants for Yb 7.5% and Yb 0% electrodes were 0.0278 min-1 and 0.0114 min-1, respectively. Furthermore, the service life of Ti/SnO2 electrodes was significantly improved after Yb doping, as demonstrated by accelerated life testing. Yb 7.5% exhibited a service life that was 2.7 times longer than that of Yb 0%. This work offers a new approach to construct Yb-Sb co-doped Ti/SnO2 electrodes with excellent electrooxidation activity and high stability for the electrochemical oxidation degradation of sulfamethoxazole.

Nitric oxide-dependent immunosuppressive function of thymus-derived mesenchymal stromal/stem cells.

BACKGROUND: The thymus is required for T cell development and the formation of the adaptive immunity. Stromal cells, which include thymic epithelial cells (TECs) and mesenchymal stromal cells (MSCs), are essential for thymic function. However, the immunomodulatory function of thymus-derived MSCs (T-MSCs) has not been fully explored. METHODS: MSCs were isolated from mouse thymus and their general characteristics including surface markers and multi-differentiation potential were characterized. The immunomodulatory function of T-MSCs stimulated by IFN-γ and TNF-α was evaluated in vitro and in vivo. Furthermore, the spatial distribution of MSCs in the thymus was interrogated by using tdTomato-flox mice corssed to various MSC lineage Cre recombinase lines. RESULTS: A subset of T-MSCs express Nestin, and are mainly distributed in the thymic medulla region and cortical-medulla junction, but not in the capsule. The Nestin-positive T-MSCs exhibit typical immunophenotypic characteristics and differentiation potential. Additionally, when stimulated with IFN-γ and TNF-α, they can inhibit activated T lymphocytes as efficiently as BM-MSCs, and this function is dependent on the production of nitric oxide (NO). Additionally, the T-MSCs exhibit a remarkable therapeutic efficacy in acute liver injury and inflammatory bowel disease (IBD). CONCLUSIONS: Nestin-positive MSCs are mainly distributed in medulla and cortical-medulla junction in thymus and possess immunosuppressive ability upon stimulation by inflammatory cytokines. The findings have implications in understanding the physiological function of MSCs in thymus.

LC-MS-based serum metabolic profiling for genitourinary cancer classification and cancer type-specific biomarker discovery.

Bladder cancer (BC) and kidney cancer (KC) are the first two commonly occurring genitourinary cancers in China. In this study, a comprehensive LC-MS-based method, which utilizes both reversed phase liquid chromatography (RPLC) and hydrophilic interaction chromatography (HILIC) separations, has been carried out in conjunction with multivariate data analysis to discriminate the global serum profiles of BC, KC, and noncancer controls. An independent test set consisting of different patients has been used to objectively evaluate the predictive ability of the analysis platform. Excellent sensitivity and specificity have been achieved in detection of KC and BC. The results suggest that serum metabolic profiling could be used for different types of genitourinary cancer diagnosis. Furthermore, cancer type-specific biomarkers were found through a critical selection criterion. As a result, eicosatrienol, azaprostanoic acid, docosatrienol, retinol, and 14'-apo-beta-carotenal  were found as specific biomarkers for BC; and PE(P-16:0e/0:0), glycerophosphorylcholine, ganglioside GM3 (d18:1/22:1), C17 sphinganine, and SM(d18:0/16:1(9Z)) were found as specific biomarkers for KC. Receiver operating characteristic (ROC) analysis was used for the preliminary evaluation of the biomarkers. These biomarkers have great potential to be used in the clinical diagnosis after further rigorous assessment.

Electrodialytic membrane suppressors for ion chromatography make programmable buffer generators.

The use of buffer solutions is immensely important in a great variety of disciplines. The generation of continuous pH gradients in flow systems plays an important role in the chromatographic separation of proteins, high-throughput pK(a) determinations, etc. We demonstrate here that electrodialytic membrane suppressors used in ion chromatography can be used to generate buffers. The generated pH, computed from first principles, agrees well with measured values. We demonstrate the generation of phosphate and citrate buffers using a cation-exchange membrane (CEM) -based anion suppressor and Tris and ethylenediamine buffers using an anion-exchange membrane (AEM) -based cation suppressor. Using a mixture of phosphate, citrate, and borate as the buffering ions and using a CEM suppressor, we demonstrate the generation of a highly reproducible (avg RSD 0.20%, n = 3), temporally linear (pH 3.0-11.9, r(2) > 0.9996), electrically controlled pH gradient. With butylamine and a large concentration (0.5 M) of added NaCl, we demonstrate a similar linear pH gradient of large range with a near-constant ionic strength. We believe that this approach will be of value for the generation of eluents in the separation of proteins and other biomolecules and in online process titrations.