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Staphylococcal enterotoxins (SE) pose a great threat to human health due to their ability to bypass antigen presentation and activate large amounts of conventional T cells resulting in a cytokine storm potentially leading to toxic shock syndrome. Unconventional T- and NK cells are also activated by SE but the mechanisms remain poorly understood. In this study,the authors aimed to explore the underlying mechanism behind SE-mediated activation of MAIT-,?? T-,and NK cells in vitro. CBMC or PBMC were stimulated with the toxins SEA,SEH,and TSST-1,and cytokine and cytotoxic responses were analyzed with ELISA and flow cytometry. All toxins induced a broad range of cytokines,perforin and granzyme B,although SEH was not as potent as SEA and TSST-1. SE-induced IFN-$\gamma$ expression in MAIT-,?? T-,and NK cells was clearly reduced by neutralization of IL-12,while cytotoxic compounds were not affected at all. Kinetic assays showed that unconventional T cell and NK cell-responses are secondary to the response in conventional T cells. Furthermore,co-cultures of isolated cell populations revealed that the ability of SEA to activate ?? T- and NK cells was fully dependent on the presence of both monocytes and $\alpha$$\beta$ T cells. Lastly,it was found that SE provoked a reduced and delayed cytokine response in infants,particularly within the unconventional T and NK cell populations. This study provides novel insights regarding the activation of unconventional T- and NK cells by SE,which contribute to understanding the vulnerability of young children towards Staphylococcus aureus infections. View Publication

BACKGROUND Circular RNA of vimentin (circ-VIM) is a predictor for poor prognosis of acute myeloid leukemia,but we had little information on its function in esophageal cancer (EC). Here we examined the effects of circ-VIM together with sevoflurane on immune escape and multiple oncogenic activities of EC. METHODS Bioinformatic tools,luciferase assay,and RNA immunoprecipitation were used to examine regulations between circ-VIM,miR-124-3p (miR-124),and PD-L1. CCK-8,wound healing,and Transwell assays were used to measure cell proliferation,migration,and invasion,respectively. The impacts of EC cells on cytotoxicity,proliferation,and apoptosis of CD8+ T cells were examined using LDH assay,CFSE staining,and Annexin V/PI staining,respectively. The in vivo tumorigenesis and lung metastases were assessed using xenograft model and tail vein injection of EC cells. RESULTS Significant upregulation of circ-VIM and PD-L1 and downregulation of miR-124 were detected in EC tissues or cells. Circ-VIM sponged miR-124 and released its suppression on the downstream target PD-L1. Sevoflurane,independent of circ-VIM,also upregulated miR-124 to lower PD-L1 expression. By modulating miR-124/PD-L1 axis,silencing circ-VIM and applying sevoflurane both inhibited immune escape and multiple oncogenic activities of EC in vitro,and suppressed xenograft growth and lung metastases in vivo. The inactivation of Ras/ERK signaling pathway was involved in suppression of malignant phenotypes by silencing circ-VIM and sevoflurane treatment. CONCLUSIONS Silencing circ-VIM and applying sevoflurane,by separately regulating miR-124/PD-L1 axis,presented synergistic effects in inhibiting immune escape and multiple malignant phenotypes of EC cells. View Publication

Systemic sclerosis (SSc) is a life-threatening chronic connective tissue disease with the characteristics of skin fibrosis,vascular injury,and inflammatory infiltrations. Though inhibition of phosphodiesterase 4 (PDE4) has been turned out to be an effective strategy in suppressing inflammation through promoting the accumulation of intracellular cyclic adenosine monophosphate (cAMP),little is known about the functional modes of inhibiting PDE4 by apremilast on the process of SSc. The present research aimed to investigate the therapeutic effects and underlying mechanism of apremilast on SSc. Herein,we found that apremilast could markedly ameliorate the pathological manifestations of SSc,including skin dermal thickness,deposition of collagens,and increased expression of $\alpha$-SMA. Further study demonstrated that apremilast suppressed the recruitment and activation of macrophages and T cells,along with the secretion of inflammatory cytokines,which accounted for the effects of apremilast on modulating the pro-fibrotic processes. Interestingly,apremilast could dose-dependently inhibit the activation of M1 and T cells in vitro through promoting the phosphorylation of CREB. In summary,our research suggested that inhibiting PDE4 by apremilast might provide a novel therapeutic option for clinical treatment of SSc patients. View Publication

Clever-1 also known as Stabilin-1 and FEEL-1 is a scavenger molecule expressed on a subpopulation of anti-inflammatory macrophages and lymphatic endothelial cells (LECs). However,its role in regulating dendritic cell (DC) trafficking and subsequent effects on immunity have remained unexplored. In this study,we demonstrate that DC trafficking from the skin into the draining lymph nodes is compromised in the absence of Clever-1. By adoptive transfer approaches we further show that the poor trafficking is due to the impaired entrance of DCs into afferent lymphatics. Despite this,injections of ovalbumin-loaded DCs into the footpads induced a stronger proliferative response of OT II T cells in the draining lymph nodes. This could be explained by the increased MHC II expression on DCs and a less tolerogenic phenotype of LECs in lymph nodes of Clever-1 knockout mice. Thus,although fewer DCs reach the nodes,they are more active in creating antigen-specific immune responses. This suggests that the DCs migrating to the draining lymph node within Clever-1 positive lymphatics experience immunosuppressive interactions with LECs. In conclusion,besides being a trafficking molecule on lymphatic vasculature Clever-1 is immunosuppressive towards migrating DCs and thus,regulates the magnitude of immune responses created by incoming DCs in the draining lymph nodes. View Publication