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Atherosclerosis (AS) is currently the leading cause of mortality worldwide, with the development of new strategies to prevent the formation and rupture of atherosclerotic plaques being a paramount area of research. Amounting evidence suggests autophagy has an important role in the pathogenesis of AS and may be a potential therapeutic target. In this study, the effect of SBI-0206965(6965), a novel inhibitor of autophagy, was tested on the development of AS in apolipoprotein E deficient (ApoE−/−) mice. Systemic application of 6965 was found to aggravate AS, with increased plaque size and decreased plaque stability in comparison with the control. Of note, it was observed that 6965 decreased the proportion of myeloid-derived suppressor cells (MDSCs). Further investigation demonstrated MDSCs markedly alleviated AS in ApoE−/− mice; while 6965 reduced the viability and promoted apoptosis of MDSCs in vitro. This is the first study describing an association between autophagy and MDSCs in AS models, providing a novel mechanism to potentially target in the management of this condition. [ABSTRACT FROM AUTHOR]

Plasmacytoid dendritic cells (pDCs) exert dual roles in immune responses through inducing inflammation and maintaining immune tolerance. A switch of pDC phenotype from pro-inflammation to tolerance has therapeutic promise in the treatment of autoimmune diseases. Vinpocetine, a vasoactive vinca alkaloid extracted from the periwinkle plant, has recently emerged as an immunomodulatory agent. In this study, we evaluated the effect of vinpocetine on phenotype of pDCs isolated from C57BL/6 mice and explored its possible mechanism. Our data showed that vinpocetine significantly downregulated the expression of CD40, CD80, and CD86 on pDCs and increased the expression of translocator protein (TSPO), the specific receptor of vinpocetine, in pDCs. Vinpocetine significantly inhibited the Toll-like receptor 9 signaling pathway and reduced the secretion of related cytokines in pDCs through TSPO. Furthermore, viability of pDCs was significantly promoted by vinpocetine. These findings imply that vinpocetine serves as an immunomodulatory agent for pDCs and may be applied for the treatment of pDCs-related autoimmune diseases. [ABSTRACT FROM PUBLISHER]

Objective To study the effect of CD11b agonist leukadherin-1 (LA1) on Toll-like receptor 7 (TLR7)- and TLR9-induced activation of mouse bone marrow-derived dendritic cells (BMDCs) and its specific mechanism. Methods BMDCs were successfully induced and the concentrations of LA1 used in the study were determined by CCK-8 assay and annexin V-FITC/PI double staining. BMDCs were treated with LA1 for 2 hours followed by stimulation of TLR7 agonist R837 and TLR9 agonist CpG1826. The expression of BMDCs surface markers CD40, CD86 and MHC-II were detected by flow cytometry; IL-6, IL-12p40 and tumor necrosis factor α (TNF-α) in the cell culture supernatant were detected by ELISA; the phosphorylation of NF-κB p65 in BMDCs was detected by Western blotting. Results LA1 concentration below 20 μmol/L had no effect on the viability and apoptosis of BMDCs. LA1 pretreatment significantly inhibited R837- and CpG 1826-induced expression of CD40, CD86 and MHC-II , and the secretion of IL-6, IL-12p40 and TNF-α in BMDCs. Moreover, LA1 pretreatment significantly inhibited the phosphorylation of NF-κB p65 activated by R837 and CpG1826 in BMDCs. Conclusion CD11b agonist LA1 can significantly inhibit the activation of TLR7 and TLR9 in BMDCs by blocking the NF-κB p65 signaling pathway.

[This corrects the article on p. 1552 in vol. 10, PMID: 29887968.]., (AJTR Copyright © 2020.)

Immune-mediated liver injury plays a crucial role in the pathogenesis of liver diseases, which can result from viral infections, autoimmunity, alcohol intake, and drug use. Concanavalin A (Con A)-induced hepatitis is a well-characterized murine model with similar pathophysiology to that of human viral and autoimmune hepatitis. Capsaicin, a selective agonist of the transient potential vanilloid subfamily member 1 (TRPV1) receptor, exhibits anti-inflammatory effects on various causes of inflammation. In the present study, we investigated the effect of capsaicin on Con A-induced hepatitis. Capsaicin (1 mg/kg body weight) was administered by intraperitoneal injection, after which (30 minutes), the mice were challenged intravenously with Con A (20 μg/g body weight). We collected serum for plasma transaminase analysis. Pro-inflammatory cytokine levels and hepatocyte apoptosis were assayed by ELISA and TUNEL, respectively. Liver samples were collected for real-time PCR, hematoxylin and eosin staining, and measuring oxidative stress and myeloperoxidase levels. Activation of splenocytes and hepatic mononuclear cells was analyzed by flow cytometry. Compared with control, the capsaicin-treated group showed significantly decreased aminotransferase levels and markedly prolonged mouse survival. Capsaicin pretreatment also attenuated hepatocyte apoptosis and oxidative stress. Furthermore, tumor necrosis factor-α and interferon-γ levels in serum and liver were significantly suppressed, while the percentage of myeloid-derived suppressor cells increased after capsaicin pretreatment. Our findings indicate that capsaicin pretreatment protects mice from Con A-induced hepatic damage and is partially involved in inhibiting hepatocyte apoptosis, oxidative stress, and inflammatory mediators as well as regulating activation and recruitment of intrahepatic leukocytes., Competing Interests: None.

Transplantation of adult human hepatic stem/progenitor cells (hHSPCs) has been considered as an alternative therapy, replacing donor liver transplantation to treat liver cirrhosis. This study assessed the antifibrotic effects of hHSPCs in mice with fibrosis induced by carbon tetrachloride (CCl 4 ) and examined the actions of hHSPCs on the fibrogenic activity of human hepatic stellate cells (HSCs) in a coculture system. Isolated hHSPCs expressed stem/progenitor cell phenotypic markers. Mice were given CCl 4 (twice weekly for 7 weeks) and hHSPC transplantation weekly. CCl 4 induced advanced fibrosis (bridging fibrosis and cirrhosis) in mice, which was prevented by hHSPC transplantation. The liver of hHSPC-transplanted mice showed only occasional short septa and focal parenchymal fibrosis, and a 50% reduction in hepatic collagen, assessed by Sirius red stain histomorphometry. Moreover, the proteins for α-smooth muscle actin (α-SMA) and collagen I were decreased. While α-SMA, collagen α1(I), and tissue inhibitor of metalloproproteinase-1 mRNAs were decreased, matrix metalloproteinase (MMP)-1 mRNA was increased, consistent with decreased fibrogenesis. MMP-2 and transforming growth factor-β were not affected. Alanine aminotransferase and aspartate aminotransferase were lower, suggesting improvement of liver function/damage. In coculture, hHSPCs elicited changes of α-SMA and fibrogenic molecules in HSCs similar to those observed in vivo , providing evidence for a functional link between hHSPCs and HSCs. A decreased HSC proliferation was noted. Thus, transplantation of hHSPCs prevents histogenesis of advanced liver fibrosis caused by CCl 4 . hHSPCs mediate downregulation of HSC activation coincident with modulation of fibrogenic molecule expression, leading to suppression of fibrogenesis both in vivo and in vitro ., Competing Interests: None.

Objective To study the effect of CD11b agonist leukadherin-1 (LA1) on the aggregation and immunosuppressive function of myeloid-derived suppressor cells (MDSCs) and its therapeutic effect on the condition of endotoxic shock mice. Methods The percentages of MDSCs , granulocytic myeloid-derived suppressor cells(G-MDSCs)and monocytic myeloid-derived suppressor cells(M-MDSCs)in spleen were detected by flow cytometry, after C57BL/6 female mice were injected of LA1 to activate through abdominal cavity for 12 hours and 48 hours. MDSCs were induced from the femur and tibia of C57BL/6 female mice in vitro. The expression levels of immunosuppressive related factors, such as interleukin 10 (IL-10), NADPH oxidase 1 (NOX1) and inducible nitric oxide synthase (iNOS) , were detected by real time quantitative PCR. C57BL/6 female mice were randomly divided into PBS group, LA1 group, PBS combined LPS group and LA1 combined LPS group. Flow cytometry was utilized to detect the ratio changes of MDSCs, G-MDSCs and M-MDSCs as well as the expression of CD86 and CD40 in macrophage, hematoxylin-eosin staining of lung and liver was utilized to detect the pathological injury, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling(TUNEL)was used to detect the apoptosis of pneumonocyte and hepatocyte and mortality analysis was reflected the severity of the disease. Based on the above indicators, we analyzed the effects of LA1 on the aggregation of MDSCs and the condition of mice in endotoxic shock. Results The ratio of MDSCs was increased by LA1 treatment for 12 and 48 hours. Further analysis of the proportions of G-MDSCs showed that LA1 treatment for 12 hours increased the proportions of G-MDSCs compared with the control group. In vitro, mRNA levels of IL-10, NOX1 and iNOS were increased after LA1 treatment in MDSCs. In vivo experiments, compared with the PBS combined LPS group, the proportions of MDSCs and G-MDSCs in LA1 combined LPS group were increased, the injuries of liver and lung were alleviated, the mortalities were reduced, and the activations of macrophage were decreased. Conclusion The activation of CD11b by LA1 alleviates endotoxin shock by promoting the aggregation of MDSCs and the expression of immunosuppressive related factors.

Objective To investigate the role of interleukin-16 (IL-16) in the development of inflammatory bowel disease (IBD) and clarify its regulatory mechanism involved in the pathogenesis of IBD. Methods Seven-week-old wild-type C57BL/6 (WT) and IL-16 knockout (IL-16 -/- ) female mice were divided into WT control group, WT dextran sulfate sodium (DSS) treatment group, IL-16 -/- control group and IL-16 -/- DSS treatment group. The DSS model groups were given the water with 25 g/L DSS for 7 days to establish the IBD models, while the control groups were given the normal water. During the modeling period, the body mass of mice was recorded to calculate the body mass curve. After 7 days, the whole colon of the mice was dissected and the level of IL-16 mRNA in the colon tissue was detected by real-time PCR. The level of IL-16 protein in the colon tissue was detected by ELISA. The expression and localization of IL-16 in the colon tissue were observed by immunofluorescence technique. HE staining was used to detect colonic pathological injury in mice. TUNEL assay was used to detect cell apoptosis of the colon tissue. Flow cytometry was used to detect the number and polarization of macrophages in peritoneal cells (F4/80, CD86). Immunohistochemical staining was used to detect the distribution of macrophages in the colon tissues. Real-time PCR was used to detect IL-6 and IL-12 mRNA levels in the colon tissue, and IL-6 and IL-12 protein levels were detected by ELISA. Results DSS induced high expression of IL-16 in the colon tissue. Compared with WT DSS treatment group, IL-16 -/- DSS treatment group showed less changes in body mass, less colon tissue damage, and markedly lower percents of apoptotic cells in the peritoneal or colonic tissues of IL-16 -/- mice. What's more, the number of macrophages, the polarization level of M1 macrophages, and the levels of the iconic inflammatory factors IL-6 and IL-12 significantly decreased in IL-16 -/- DSS treatment group compared with WT DSS treatment group. Conclusion IL-16 can aggravate DSS-induced IBD by promoting the polarization of M1 macrophages.

Cancer stem cells (CSCs) play important roles in tumor initiation, metastasis, and progression. They are also mainly responsible for high treatment failure rates. Identification and characterization of CSCs are crucial for facilitating the detection, prevention, or therapy of cancer. Great efforts have been paid to develop an effective method and the ideal method for CSCs research is still in the going. In our study, we created an ultra-low concentration of serum and non-adhesive (ULCSN) culture system to enrich CSCs from murine lewis lung cancer cell line LL/2 with cell spheres structure and characterize the LL/2 CSCs properties. Their characteristics were investigated through colony formation, spheres formation, chemoresistance, flow cytometry for putative stem cell markers, such as CD133, CD34 and CD45, immunofluorescence staining and tumor initiation capacity in vivo . Tumor spheres were formed within 7-10 days under the condition of ULCSN culture system. Compared with adherent parental LL/2 cells, the colony capacity, chemo-resistance, and expression of stem cell markers increased significantly in addition to tumor-initiating capability in the tumor sphere cells. Using the ULCSN culture system, an available isolation method of lewis lung CSCs was established, which is simple, effective, and inexpensive compared with the cytokines attachment serum free culture method. The stem cell properties of the tumor sphere LL/2 cells reflected the CSCs phenotypes. We developed a useful CSCs model for basic and pre-clinical studies for lung cancer and other types of cancer., Competing Interests: None.

Objective: To detect the expression of interleukin 16 (IL-16) in skin allografts of recipient mice and the serum level of IL-16., Methods: Two different mouse models of skin allografts were used: the isotransplant group (C57BL/6--C57BL/6, n=45) and the allotransplantation group (BALB/c--C57BL/6, n=45). The level of IL-16 in sera and skin graft homogenates was tested by ELISA at 1, 3, 5 and 7 days after transplantation and the expression of IL-16 mRNA in skin allografts was measured by reverse transcription PCR at the same time points., Results: At 3, 5 and 7 days after skin transplantation, the levels of IL-16 protein and mRNA in the skin allografts and serum level of IL-16 in the allotransplantation group were significantly higher than those in the isotransplant group., Conclusion: The expression of IL-16 is increased in the mouse skin allografts.

Objective: Aqueous extract of Caesalpinia sappan (CSE) has immunosuppressive activities, but the mechanism remains unknown. This study was to investigate the effect of CSE on the balance between CD4(+) CD25(+) T cells and Th17 cells., Methods: Allografted Balb/c recipients were intraperitoneally treated with CSE for 14 continuous days, and the graft survival was observed. The spleen cells and peripheral blood of the recipient mice were harvested for phenotyping by flow cytometry, detection of gene expression by real-time PCR and cytokine detection by ELISA., Results: CSE prolonged skin allograft survival, increased the percentage and number of CD4(+) CD25(+) T cells, the expression of Foxp3 and STAT5 in spleen cells, the serum levels of IL-10 and TGF-β1, whereas reduced the percentage and number of Th17 cells and serum IL-17 level in Balb/c recipients., Conclusion: CSE expanded CD4(+) CD25(+) T cells and decreased Th17 cells in vivo thereby improving skin allograft survival in mice, indicating that CSE affects the balance between CD4(+) CD25(+) T cells and Th17 cells in the graft to induce rejection.