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Surfactants as synergistic agents are necessary to improve the stability and utilization of pesticides, while their use is often accompanied by unexpected release into the environment. However, there are no efficient strategies available for screening low-toxicity surfactants, and traditional toxicity studies rely on extensive experimentation which are not predictive. Herein, a commonly used agricultural adjuvant Triton X (TX) series was selected to study the function of amphipathic structure to their toxicity in zebrafish. Molecular dynamics (MD) simulations, transcriptomics, metabolomics and machine learning (ML) were used to study the toxic effects and predict the toxicity of various TX. The results showed that TX with a relatively short hydrophilic chain was highly toxic to zebrafish with LC 50 of 1.526 mg/L. However, TX with a longer hydrophilic chain was more likely to damage the heart, liver and gonads of zebrafish through the arachidonic acid metabolic network, suggesting that the effect of surfactants on membrane permeability is the key to determine toxic results. Moreover, biomarkers were screened through machine learning, and other hydrophilic chain lengths were predicted to affect zebrafish heart health potentially. Our study provides an advanced adjuvants screening method to improve the bioavailability of pesticides while reducing environmental impacts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Single-domain antibodies (sdAbs), initially identified in camelids or sharks and commonly referred to as nanobodies or VNARs, have emerged as a promising alternative to conventional therapeutic antibodies. These sdAbs have many superior physicochemical and pharmacological properties, including small size, good solubility and thermostability, easier accessible epitopes, and strong tissue penetration. However, the inherent challenges associated with the animal origin of sdAbs limit their clinical use. In recent years, various innovative humanization technologies, including complementarity-determining region (CDR) grafting or complete engineering of fully human sdAbs, have been developed to mitigate potential immunogenicity issues and enhance their compatibility. This review provides a comprehensive exploration of sdAbs, emphasizing their distinctive features and the progress in humanization methodologies. In addition, we provide an overview of the recent progress in developing drugs and therapeutic strategies based on sdAbs and their potential in solid tumor treatment, such as sdAb-drug conjugates, multispecific sdAbs, sdAb-based delivery systems, and sdAb-based cell therapy., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Authors.)

Monoclonal antibody-based therapeutics have achieved remarkable success in treating a wide range of human diseases. However, conventional systemic delivery methods have limitations in insufficient target tissue permeability, high costs, repeated administrations, etc. Novel technologies have been developed to address these limitations and further enhance antibody therapy. Local antibody delivery via respiratory tract, gastrointestinal tract, eye and blood-brain barrier have shown promising results in increasing local concentrations and overcoming barriers. Nucleic acid-encoded antibodies expressed from plasmid DNA, viral vectors or mRNA delivery platforms also offer advantages over recombinant proteins such as sustained expression, rapid onset, and lower costs. This review summarizes recent advances in antibody delivery methods and highlights innovative technologies that have potential to expand therapeutic applications of antibodies., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

As important environmental factors, the light spectra and tank colours have not received sufficient attention. Most fishes have the ability to perceive environment, distinguish colours, and exhibit preferences or aversions towards different environments, which can provide a reference for the design of their rearing environment. Tiger puffer (Takifugu rubripes) is an important mariculture species in China and East Asia, but its preference for illumination spectra and tank colours is unclear. This study focuses on the preferences of juvenile tiger puffers for different spectra and tank background colours in different rearing backgrounds and body sizes. The experiments were conducted in a preference testing device, and the behavioural videos were recorded and analysed using a motion behaviour tracking system (EthoVision XT 12). The results show that the puffers showed preference for short-wavelength lights ((i.e., cyan, green, etc.), avoidance of long-wavelength light (i.e., red) and less stay time in the full light spectrum and dark. For tank colours, the puffers showed a preference for light background colours (i.e., white), and avoidance of deep background colours (i.e., dark, red, etc.). Fish body sizes and original breeding environment could significantly affect the selective preference of juvenile puffer (P < 0.05). Large puffers preferred green tank colour than small ones, while small ones preferred grey and red. The puffers reared in green light and grey tank for 3 months preferred green light spectrum and green tank colour compared with those reared in full spectrum and grey tank, while the fish reared in full spectrum preferred grey tank colour and area without light. It was also found that the movement rate of juvenile puffers was affected by the light spectra and tank colours and was positively correlated with light wavelength (P < 0.05). Therefore, for tiger puffer breeding, short-wavelength light spectrums (cyan, green, etc.) and light-coloured tank backgrounds (white) are recommended. Long-wavelength Light-emitting diodes and dark tank colours should be avoided in breeding. This study would provide a reference basis for fish light spectra and background colour preference studies, as well as for the improvement of breeding welfare and production efficiency of juvenile tiger puffer., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

As a new type of environmental pollutant, microplastics have been garnered increasing attention, especially in regard to their effects on the reproductive system. However, researchers have yet to report whether prevention and treatment measures exist for reproductive injury caused by microplastics. The aim of this study was therefore to explore the mechanism of spermatogenic injury induced by polystyrene microplastics (PS-MPs) and the intervention effect of probiotics based on the gut microbiota-testis axis. Mice were orally exposed for 35 days to 5 µm of PS-MPs with a gavage dose was 0.1 mg/day, and the intervention group was given probiotics (Lactobacillus, Bifidobacterium longum, and Enterococcus) orally. Fecal samples were then subjected to 16 S rRNA sequencing analysis, and sperm motion was analyzed by a Hamilton-Thorne Sperm analyzer. The results showed that PS-MPs exposed mice had significant spermatogenic dysfunction and testicular inflammation. In addition, the intestinal microbial structure of exposed mice changed significantly; the abundance of Lactobacillus decreased, and the abundance of Prevotella increased. Furthermore, with fecal microbiota transplantation, the recipient mice showed a significant decrease in sperm quality. However, probiotics supplementation helped inhibit the activation of IL-17A signaling driven by gut microbes, thereby alleviating the inflammatory response and improving sperm quality decline caused by PS-MPs. These results may provide a scientific basis for further understanding of the mechanism of male reproductive damage caused by environmental pollutants such as microplastics and for novel reproductive damage intervention measures., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Low pesticide efficiency has caused serious environmental pollution and economic loss, which are closely related to each link in the targeted delivery of pesticides. However, the existing strategies for improving pesticide utilization rate are not comprehensive, and the regulation of foliar absorption and biological activity has been neglected. As surfactants are the most important agricultural synergists, the impact, wetting, adhesion, and leaf retention behaviors of pyraclostrobin (PYR) droplets containing the surfactant Triton X (TX) series on hydrophobic scallion leaf surfaces were studied. The results showed that TX-102 can sufficiently reduce the splash and roll of droplets when they impact inclined leaves, owing to its low dynamic surface tension. Moderate wetting ability and high adhesion also maximizes leaf retention of the TX-102-added PYR solution sprayed on scallion leaves. Furthermore, TX-102 improved the permeation and absorption of PYR in scallion leaves through the synergistic effects of opening the stomata and dissolving the waxy layer. The synergistic bioactivity of TX-102 against pathogenic fungi Alternaria porri and its safety to non-target organism zebrafish have also been demonstrated. Our study provides a more comprehensive theoretical rationale for screening adjuvants to improve the effectiveness and bioavailability of pesticides and reduce the risk of pesticides entering the environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Immune checkpoint blockade has displayed substantial anti-tumor resistance in a variety of forms of cancer, but the fundamental regulation role remains unclear, and several questions continue to be addressed. PD-1/PD-L1 has been recognized as an anti-cancer drug target for several years, and through targeting the PD-1/PD-L1 signaling pathway, many monoclonal antibodies have thus far produced promising results in cancer therapy. The discovery of small-molecule inhibitors focused on the PD-1/PD-L1 signaling pathway is steadily reviving over decades, owing to the intrinsic shortcomings of the antibodies. PD-1 function and its PD-L1 or PD-L2 ligands are essential for the activation, proliferation, and cytotoxic secretion of T-cells in cancer to degenerate anti-tumor immune response. The axis PD-1/PD-L1 is important for the immune escape of cancer which has an immense impact on cancer treatment. In this review, we summarize the function of PD-1 and PD-L1 in cancer and aiming to enhance cancer therapy., (Copyright © 2021. Published by Elsevier Inc.)

Aims: This study aimed to investigate the effect of previously synthesized 4,5-diazafluorene derivative (14c) on γδ T cell-mediated cytotoxicity against renal cell carcinoma (RCC)., Materials and Methods: A real-time cell analyzer monitored cell proliferation, and Cell Counting Kit-8 determined cell viability. A reverse transcription-polymerase chain reaction analyzed gene expression, and protein expression was determined by cellular immunofluorescence analysis and Western blot., Key Findings: The compound 14c induced the expression of immunomodulatory molecules, such as natural killer group 2, member D ligands (NKG2DLs), fibroblast-associated (Fas) death receptor, and tumor necrosis factor-related apoptosis-inducing ligand receptors (TRAILRs) in RCC. In addition, 14c induced DNA damage responses in RCC. Blocking DNA damage by KU-55933 reduced the effect of γδ T cells on 14c-treated RCC, suggesting that DNA damage responses were involved in the augmentation of γδ T cell-mediated cytotoxicity. Treating 786-O cells with a nitrogen-containing bisphosphonate prodrug further enhanced the anti-tumor effect of γδ T cell plus 14c combination treatment., Significance: The present evidence indicates that 14c induced DNA damage responses in RCC and augmented γδ T cell-mediated cytotoxicity primarily through NKG2D/NKG2DLs pathways, suggesting potential cancer immunotherapy for harnessing γδ T cells and small compounds that induce DNA damage responses., (Copyright © 2021. Published by Elsevier Inc.)

LncRNA PCGEM1 (PCGEM1) has been reported to exert essential effects on the development and progress of various tumors, while the detailed effects and possible mechanisms of PCGEM1 in cervical carcinoma remain unknown. In the present study, PCGEM1 was over-expressed in cervical carcinoma cells as evidenced by real-time quantitative polymerase chain reaction (RT-qPCR) assay. Knockdown of PCGEM1 significantly repressed proliferation, migration, and invasion, while induced G1 arrest in cervical carcinoma cells. In addition, PCGEM1 was predicted to target miR-642a-5p by bioinformatics software, which was further confirmed by luciferase reporter assay. Besides, RT-qPCR assay indicated that miR-642a-5p expression was decreased in cervical carcinoma cells and knockdown of PCGEM1 could accelerate miR-642a-5p expression. Moreover, inhibition of miR-642a-5p partly abolished the functions of PCGEM1 knockdown on proliferation, cell cycle, migration and invasion of cervical carcinoma cells. Furthermore, miR-642a-5p could bind to the 3'-UTR of LGMN, which was over-expressed in the cervical carcinoma cells. Suppression of LGMN partly restored the functions of miR-642a-5p inhibitor on proliferation, cell cycle distribution, migration and invasion in the cervical carcinoma cells treated with the PCGEM1 shRNA. Taken together, our data indicated that knockdown of PCGEM1 inhibited proliferation, migration and invasion in cervical carcinoma by modulating the miR-642a-5p/ LGMN axis., (Copyright © 2020. Published by Elsevier Inc.)

Aims: This study aimed to analyze the impact of four synthesized benzoxazinone derivatives as screening drugs on c-Myc-overexpressed cancer cells (H7402, HeLa, SK-RC-42, SGC7901, and A549) and to explore their interaction mechanisms in detail., Materials and Methods: Using morphological analysis, real-time cytotoxicity analysis, wound healing assay, reverse transcription PCR, electrophoretic mobility shift assay, and circular dichroism spectroscopy techniques., Key Findings: Results revealed that these four compounds could inhibit proliferation of SK-RC-42, SGC7901, and A549 cells in five cancer cell lines to varying degrees and significantly hinder migration. More importantly, the RT-PCR assay showed that the compounds could surprisingly downregulate the expression of c-Myc mRNA in a dose-dependent manner in the five cancer cells, which may be one of the causes of cancer cell proliferation in vitro inhibition. Further EMSA assays demonstrated that at the molecular level of DNA, four compounds can induce the formation of G-quadruplexes (G4-DNAs) in the c-Myc gene promoter. In addition, the CD result of compound 1 clearly indicates that it specifically induces a c-Myc GC-rich 36mer double-stranded DNA in the c-Myc promoter to form a G-quadruplex hybrid configuration. In conclusion, the compounds studied could dose-dependently inhibit the growth and migration of the cancer cells being investigated. This is positively associated with the reduction of overexpression of the c-Myc gene, which may be significantly regulated by the association of compounds with the G-quadruplexes produced in the c-Myc gene promoter region., Significance: We conclude that three compounds merit further study, particularly against non-small-cell lung cancer, as leading compounds of anticancer drugs., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aims: Competing endogenous RNAs (ceRNAs) play essential roles in cancer pathogenesis and those in exosomes have been the promising biomarkers for cancer diagnose and therapy. We aim to identify potential active ceRNA pairs in cancer blood exosomes by combining TCGA and exoRBase., Main Methods: Two strict screening criteria were implemented, including hypergeometric test on the targets predicted by RNA22 for differential miRNAs and Pearson test on the candidate mRNAs and lncRNAs for each cancer. Then2638292, 4925485 and 70669 ceRNAs in blood exosomes are available for colorectal cancer (CRC), hepatocellular carcinoma (HCC) and pancreatic adenocarcinoma (PAAD), respectively., Key Findings: A comprehensive functional analysis on differential miRNAs in cancer blood exosomes indicates that they play important roles in development of cancer by degrading or inhibiting the post-transcription translation level of mRNA or by acting as mediators to regulate the expression of mRNA. Topological and biological functional analysis of ceRNA networks demonstrate that hub ceRNAs involve in cancer-related biological pathways and processes, so as to influence the occurrence and development of cancer and would be the potential biomarkers for three cancers. Finally, we designed a web-accessible database, ExoceRNA Atlas (https://www.exocerna-atlas.com/exoceRNA#/) as a repository of ceRNAs in blood exosomes. It can friendly search, browse and visualize ceRNA networks of the query genes along with giving the detailed functional analysis results. The entire ceRNA data can also be freely downloaded., Significance: ExoceRNA Atlas will serve as a powerful public resource for identifying ceRNAs and greatly deepen our understanding their functions in cancer exosomes., Competing Interests: Declaration of competing interest The authors declare that no conflict of interest exists., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Carbon disulfide (CS 2 ) is regarded as a common occupational poison that is widely used in the textile industry in China. Our previous research suggests that CS 2 can induce significant implantation disorders in pregnant mice; however, the specific mechanism remains unclear. Uterine conception in mice must undergo decidualization, which is the prerequisite for propitious blastocyst implantation into the endometrium. Therefore, in this study, we established models of pregnant mice to explore the toxic effects of CS 2 on decidualization to elucidate the basic mechanism of implantation disorder after CS 2 exposure. The uterine tissues were immediately collected according to the predetermined endpoints to measure the expression levels of IGFBP1 and PRL (markers of decidualization differentiation), IL-11 (representing the secretory function of decidual cells), AKT and pAKT by western blotting, RT-PCR, immunohistochemical staining, H&E staining and ELISA. N-carbamoyl glutamic acid (NCG) acted as an agonist of AKT to verify the upstream regulatory mechanism of decidualization disorder by CS 2 . The results showed that the normal reaction of decidual transformation was obviously disrupted by CS 2 upon 3.5 dpc and 4.5 dpc exposure. The blastocyst did not adhere to the epithelium after 3.5 dpc-exposure and did not invade the endometrium after 4.5 dpc-exposure, resulting in its suspension in the uterine cavity, stagnation and eventual loss. The proteins expression levels were decreased by 95.2% for IGFBP1 and 76.2% for PRL at the 4.5 dpc endpoint after 3.5 dpc CS 2 exposure compared with the control. Simultaneously, the mRNA and protein expression levels of IL-11 in uterine tissues were significantly reduced by CS 2 , and consistent decreasing trends over time were observed for IGFBP1 and PRL, compared with the control. Additionally, the ratio of pAKT/AKT protein expression was decreased by 72.2% and 94.8% at 12 h and 18 h after 3.5 dpc exposure and by 53.3% and 74.3% at 6 h and 12 h after 4.5 dpc exposure, respectively, compared with the corresponding controls. Furthermore, NCG could recover the IGFBP1 and PRL protein expression, which was increased by 27.5% and 52.3% at 4.5 dpc and 6.5 dpc, respectively, after 3.5 dpc exposure for IGFBP1 and by 30.3% at 6.5 dpc after 4.5 dpc exposure for PRL, compared with CS 2 exposure alone. Collectively, this study suggested that the decidualization disorder caused by CS 2 at the window of implantation in pregnant mice, which is triggered by pAKT, contributed to the implantation disorder and eventually led to embryo loss. It is worth noting that our study may provide a new perspective and reference for exploring the toxic mechanism of implantation disorder and even infertility in harmful circumstances., (Copyright © 2019. Published by Elsevier Inc.)

Liver fibrosis is a common pathological consequence of liver injury, which increases liver failure-related morbidity and mortality. Hence, anti-fibrotic treatment is urgently needed. Oxidative stress plays a pivotal role in the progression of liver fibrosis. Thus, targeting ROS may be an effective strategy for liver fibrosis treatment. In this study, we investigated four benzoquinones derivatives, including 5-isopropyl-2-methyl-1,4-benzoquinone (TQ), 2-tert-butyl-1,4-benzoquinone ( t Bu-Q) 2,5-dimethyl-p-benzoquinone (Dime-Q) and p-benzoquinone (Ph-Q), as well as the evaluation of their antioxidant activity and anti-fibrotic effects on activated hepatic stellate cells and TAA-induced mice. Electrochemical analysis showed that all compounds possessed antioxidant property. The result was first confirmed by in vitro experiments, which revealed potential anti-fibrotic activity of all four compounds at the cellular level. Benzoquinone derivatives act as ROS-scavenging molecules, which modulated the TLR4-CD14 signaling pathway to inhibit the expression of procaspase-1 and IL-1β in cells, induced apoptosis via a mitochondrial pathway by upregulating the ratio of Bax/Bcl-2 and by activating caspase-3, as well as inhibited the expression of the anti-apoptotic proteins FLIP and XIAP in activated LX-2 cells. In addition, a TAA (Thioacetamide)-induced mouse model was used to further validate the results. Treatment with benzoquinone derivatives significantly decreased the levels of liver injury markers and lipid peroxidation caused by excessive ROS, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA). Moreover, treatment with benzoquinone derivatives significantly inhibited extracellular matrix (ECM) deposition and downregulated the mRNA and protein expression of liver fibrosis markers, such as collagen I, alpha-smooth muscle actin (α-SMA), and TIMP-1. In summary, these results indicate that benzoquinone derivatives may act as potential therapeutic drugs against liver fibrosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Carbon disulfide (CS2) exposure can cause embryo implantation loss but the mechanism remains unclear. Earlier study revealed that the 4th day of gestation (GD4) and GD5 were the most sensitive exposure time on which the number of implanted embryos decreased obviously in mice. Leukemia inhibitory factor (LIF) in maternal uterine tissue is involved in embryo implantation, which is produced by endometrium and Th2 cells that participate in cellular adhesion of maternal-fetal interface. We herein investigated the effect of CS2 on the expression of LIF in uterine tissue and its regulatory mechanism in Kunming mice. Exposure was on GD3, GD4, GD5 and GD6, respectively, single administration (631.4 mg/kg), and the indexes were arranged in time series after exposure. The results showed that LIF gene breakage was captured at the 18th hour after exposure by Comet-FISH and the protein and mRNA of LIF in uterine tissue were down-regulated after exposure through the peri-implantation period. In addition, sex steroid hormones, progesterone (P4) and oestrogen (E2) were detected since they can stimulate synthesis of LIF from endometrial cells. Results showed that P4 and E2 in serum were down-regulated at all the endpoints of CS2 exposure groups. These findings suggested that the down-regulated LIF induced by the decreased P4 and E2 after mice exposure to CS2 might be important reasons for implantation disorders., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Carbon disulfide (CS2) exposure might disrupt embryo implantation in females during pregnancy but the relevant mechanism remains unclear. Since integrin β3 has shown to be one of the cell adhesion molecules involved in embryo implantation, the current study examined the effect of CS2 exposure during the peri-implantation period on the protein and mRNA expression of integrin β3 and its DNA methylation degree in the uterine tissue of gestational mice. Exposure was on the 3rd day of gestation (GD3), GD4, GD5 and GD6, respectively, one time administration (631.4 mg/kg). The number of implanted embryos on GD9 was observed and compared with the control, it was decreased by 32.92%, 56.11%, 56.11% and 51.21%, respectively, which revealed that GD4 and GD5 were the most sensitive time for embryotoxicity. The protein and mRNA expression of integrin β3 were detected each day after exposure till the GD7 endpoint. It down-regulated the protein and mRNA expression of integrin β3 in uterine tissue and there was a positive correlation between the number of embryos and the expression of protein on the first and second day after exposure. However, the degree of integrin β3 DNA methylation was not affected, which was detected by bisulfite sequencing polymerase chain reaction (BSP) method. These findings suggest that the decreased protein and mRNA level of integrin β3 in the uterine tissue after mice exposure to CS2 might be relevant to the underlying mechanism of embryo implantation disorders, but DNA methylation of integrin β3 does not contribute to this action., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Chronic kidney disease (CKD) leads to an 18-fold increase in cardiovascular complications not fully explained by traditional risk factors. Levels of renalase, a recently discovered oxidase that metabolizes catecholamines, are decreased in CKD. Here we show that renalase deficiency in a mouse knockout model causes increased plasma catecholamine levels and hypertension. Plasma blood urea nitrogen, creatinine, and aldosterone were unaffected. However, knockout mice had normal systolic function and mild ventricular hypertrophy but tolerated cardiac ischemia poorly and developed myocardial necrosis threefold more severe than that found in wild-type mice. Treatment with recombinant renalase completely rescued the cardiac phenotype. To gain insight into the mechanisms mediating this cardioprotective effect, we tested if gene deletion affected nitrate and glutathione metabolism, but found no differences between hearts of knockout and wild-type mice. The ratio of oxidized (NAD) to reduced (NADH) nicotinamide adenine dinucleotide in cardiac tissue, however, was significantly decreased in the hearts of renalase knockout mice, as was plasma NADH oxidase activity. In vitro studies confirmed that renalase metabolizes NADH and catecholamines. Thus, renalase plays an important role in cardiovascular pathology and its replacement may reduce cardiac complications in renalase-deficient states such as CKD., (© 2011 International Society of Nephrology)

Immune thrombocytopenia depends upon Fc receptor-mediated phagocytosis that involves signaling through the SH2 tyrosine kinase, Syk. We designed small interfering (siRNA) sequences complementary to Syk coding regions to decrease the expression of Syk in the human macrophage cell line, THP-1. To evaluate the functional effect of siRNA on phagocytosis, we developed a new in vitro assay for antibody-mediated platelet ingestion by THP-1 cells. Incubation of THP-1 cells at 37°C with fluorescence-labeled platelets and anti-platelet antibody promoted ingestion of platelets that could be quantitated by flow cytometry. Transfection of THP-1 cells with Syk-specific siRNA resulted in a reduction in the amount of FcγRII-associated Syk protein. Coincident with decreased Syk expression, we observed inhibition of antibody-mediated platelet ingestion. These results confirm a key role for Syk in antibody-mediated phagocytosis and suggest Syk-specific siRNA as a possible therapeutic candidate for immune thrombocytopenia., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Although recent evidence supports a functional relationship between platelet endothelial cell adhesion molecule (PECAM-1) and Syk tyrosine kinase, little is known about the interaction of Syk with PECAM-1. We report that down-regulation of Syk inhibits the spreading of human THP-1 macrophage cells. Moreover, our data indicate that Syk binds PECAM-1 through its immune tyrosine-based inhibitory motif (ITIM), and dual phosphorylation of the ITIM domain of PECAM-1 leads to activation of Syk. Our results indicate that the distance between the phosphotyrosines could be up to 22 amino acids in length, depending on the conformational flexibility, and that the dual ITIM tyrosine motifs of PECAM-1 facilitate immunoreceptor tyrosine-based activation motif-like signaling. The preferential binding of PECAM-1 to Src homology region 2 domain-containing phosphatase-2 or Syk may depend on their relative affinities, and could provide a mechanism by which signal transduction from PECAM-1 is internally regulated by both positive and negative signaling enzymes., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Outcome for highly immunogenic lung transplantation remains unsatisfactory despite the development of potent immunosuppressants. The poor outcome may be the result of a lack of minimally invasive methods to detect early rejection. There is emerging clinical evidence that, paradoxically, expression of forkhead box P3 (FOXP3, a specific marker for the regulatory T cells) is upregulated within rejecting grafts., Methods: Orthotopic lung transplantation was performed using miniature swine without immunosuppression. Rejection was monitored by chest radiography and open lung biopsy. Expressions levels of FOXP3, perforin, Fas-L and IP-10 mRNA were quantified in the peripheral blood. In addition, rescue immunosuppressive therapy (steroid plus tacrolimus) was administered on post-operative day (POD) 4 or 6., Results: Early rejection was detected by open lung biopsy, but misdiagnosed by chest radiography on POD 4. Expression of FOXP3 in the peripheral blood reached its highest value as early as POD 4, followed by a decline. Such an increase of FOXP3 was not observed in recipients given high-dose tacrolimus. Neither perforin, Fas-L or IP-10 in the peripheral blood exhibited significant fluctuations in the early phase of rejection. Rescue immunosuppressive therapy from POD 4, when peak FOXP3 was seen, prolonged graft survival (27.2 days, versus 9.1 days without immunosuppression, p < 0.001), in contrast to POD 6, when rejection was suspected by chest radiography (11.5 days, p = not statistically significant [NS])., Conclusions: In a miniature swine lung transplantation model, the FOXP3 mRNA level in the peripheral blood was upregulated at an early phase of rejection. The clinical implication of this finding remains to be elucidated.

The detailed process of how dystrophic muscles are replaced by fibrotic tissues is unknown. In the present study, the immunolocalization and mRNA expression of connective tissue growth factor (CTGF) in muscles from normal and dystrophic human muscles were examined with the goal of elucidating the pathophysiological function of CTGF in muscular dystrophy. Biopsies of frozen muscle from patients with Duchenne muscular dystrophy (DMD), Becker muscular dystrophy, congenital muscular dystrophy, spinal muscular atrophy, congenital myopathy were analyzed using anti-CTGF polyclonal antibody. Reverse transcription-polymerase chain reaction (RT-PCR) was also performed to evaluate the expression of CTGF mRNA in dystrophic muscles. In normal muscle, neuromuscular junctions and vessels were CTGF-immunopositive, which suggests a physiological role for CTGF in these sites. In dystrophic muscle, CTGF immunoreactivity was localized to muscle fiber basal lamina, regenerating fibers, and the interstitium. Triple immunolabeling revealed that activated fibroblasts were immunopositive for CTGF and transforming growth factor-beta1 (TGF-beta1). RT-PCR analysis revealed increased levels of CTGF mRNA in the muscles of DMD patients. Co-localization of TGF-beta1 and CTGF in activated fibroblasts suggests that CTGF expression is regulated by TGF-beta1 through a paracrine/autocrine mechanism. In conclusion, TGF-beta1-CTGF pathway may play a role in the fibrosis that is commonly observed in muscular dystrophy.

In the setting of our pediatric living-donor liver transplantation (LDLT), 87 patients (15.0% of all the patients: significantly higher proportion, compared with those of other transplant centers) achieved complete withdrawal of immunosuppression, which is referred to as "operational tolerance". Immunosuppressants were completely discontinued for 54 patients as scheduled, and for 33 because of EBV infection or other complications. Immunological analyses of the peripheral blood derived from operationally tolerant patients demonstrated that non-deletional tolerance takes place in which potentially reactive T cells to donor-antigens remain physically in the immune repertoire, but specifically suppressed by certain mechanisms. Not only CD4(+)CD25(high+) T cells were increased in the proportion in the tolerant patients' peripheral lymphocytes and suppressed MLR specifically to the donor antigen, but also FOXP3 expressing cells were present within the tolerant liver. Thus, among several mechanisms accounting for non-deletional tolerance, Tregs are likely to involve at least in part in our tolerant patients. Vdelta1gammadeltaT cells, a subset of gammadeltaT cells, which otherwise reside mainly in the intestine, emerge into the peripheral blood during successful pregnancy but not abortive pregnancy. Since Vdelta1gammadeltaT cells produce massive IL-10, it is proposed that Vdelta1gammadeltaT cells induce fetomaternal tolerance by promoting Th2 immune deviation. Consistent with pregnancy, IL-10 producing Vdelta1gammadeltaT cells emerge into the blood of our tolerant patients. This may reflect a common feature between fetomaternal tolerance and transplant tolerance. We began protocol biopsy in post-LDLT patients who exhibit normal liver function from January 2003. Operationally tolerant patients, albeit showing normal liver function, exhibited decrease in size and increase in number of the bile duct and the fibrosis to a greater extent, compared with patients on maintenance immunosuppression. This warrants serial protocol biopsy before and after complete cessation of immunosuppression even in the presence of normal liver function.

MHC class I allo-grafts can be directly rejected by recipient CD8 T cells and be indirectly rejected by recipient CD4 T cells. Although the experimental results using the bm mutant and C57BL/6 mice indicated that CD4-mediated rejection of class I-disparate grafts is a relatively weak process and is expected to be more sensitive to additional exogenous immunosuppression, it is unclear that whether this mechanism can be used for inducing a specific tolerance of class I disparate grafts. In this study, we hypothesize that a short course of FK506 may induce a specific tolerance of class I-disparate skin grafts in the CD8-depleted recipients. K(b)-transgenic C3H mice, Tg.H-2 K(b)-1 and Tg.H-2 K(b)-2 mice that express high copies and low copies of K(b)-antigen respectively were used as donors. Wild type C3H mice (H-2(k)) in which either CD4 or CD8 T cells were depleted by administration of anti-CD4 or CD8 monoclonal antibody (mAb) were used as recipients. Results showed that FK506 promoted longer survival of allo-K(b) skin grafts in CD8-depleted C3H mice than in CD4-depleted C3H mice. Graft survival from Tg.H-2 K(b)-2 mice was significantly longer than Tg.H-2 K(b)-1 mice. A short course of FK506 induced long-term survival of skin grafts from Tg.H-2K(b)-2 mice, but not from Tg.H-2K(b)-1 mice in CD8-depleted C3H recipients, even after FK506 was stopped. These mice also accepted grafts of Tg.H-2K(b)-1 mice when challenged with skin grafts from Tg.H-2K(b)-1 mice, but promptly rejected third party skin grafts from BALB/c (H-2(d)) mice. T cells from K(b)-tolerant C3H mice did not respond to allo-K(b)-antigen in in vitro assays of mixed lymphocyte culture and cell-mediated cytotoxicity. In conclusion we found that a short course of FK506 treatment and low amounts of K(b)-antigen induced a K(b)-specific tolerance in the CD8-depleted recipients, and this tolerance maintained even after withdrawing the anti-CD8 mAb treatment.

Oxidative stress is believed to play a role in the pathogenesis of many diseases. Here we report that isopentenyl diphosphate (IPP), the 5-carbon building unit of all isoprenoids, is a potent antioxidant that is capable of inhibiting oxidative DNA damage at picomolar concentrations (IC50 = 1.7 x 10(-11) M). The diphosphate moiety is essential, since isopentenyl monophosphate (IMP) is unable to trigger antioxidative signaling. The 20-carbon isoprenyl, geranylgeranyl diphosphate (GGPP), but not the 15-carbon farnesyl diphosphate, displays similar genoprotective effects. The pathway activated by IPP is distinct from that of 2-chloroadenosine (2CA). 2CA-mediated genoprotective signaling is transduced through an A2a or A2b adenosine receptor (AR) and can be blocked by the cyclic AMP (cAMP)-dependent protein kinase (PKA) inhibitor, H-89. In contrast, IPP signaling is independent of A2aAR, A2bAR, cAMP or PKA. Unlike the 2CA-mediated pathway, the effect of IPP is dependent on the mevalonate pathway, a geranylgeranylated protein and on intact proteasome activity. Thus, IPP is a potent activator of a novel genoprotective pathway. These findings shed new light on the role of isoprenoids in oxidative stress biology and may help to develop novel preventive strategies against oxidative damage.

Adenosine has been previously shown to be a cytoprotective paracrine released by injured cells. However, it is presently unknown whether extracellular adenosine can prevent DNA damage. We show here that the adenosine analog, 2-chloroadenosine (2CA), has a potent (IC(50)=2.04 x 10(-9)M) genoprotective effect in cells subsequently exposed to H(2)O(2). The genoprotective signaling is transduced through adenosine receptors of the A2a and A2b subtypes. Increasing [cAMP](i) by forskolin or by cell permeable 8-br-cAMP produced a similar effect, whereas inhibiting the cAMP-mediated pathway with H-89, or increasing [nitric oxide](i) or [cGMP](i) blocked 2CA effect. Proteasomal inhibitors had no impact on 2CA signaling, while lithium chloride, an inhibitor of glycogen synthase kinase 3beta, completely blocked 2CA-induced genoprotective effect. These data indicate for the first time that extracellular adenosine protects cells against imminent oxidative DNA damage and suggest that prophylactic activation of this pathway prior to genotoxic challenges might reduce mutation rates.