Naturally occurring CD4+CD25+ regulatory T cells (Treg) exert an important role in mediating maternal tolerance to the fetus during pregnancy, and this effect might be regulated via maternal estrogen secretion. Although estrogen concentration in the pharmaceutical range has been shown to drive expansion of CD4+CD25+ Treg cells, little is known about how and through what mechanisms E2 within the physiological concentration range of pregnancy affects this expansion. Using in vivo and in vitro mouse models in these experiments, we observed that E2 at physiological doses not only expanded Treg cell in different tissues but also increased expression of the Foxp3 gene, a hallmark for CD4+CD25+ Treg cell function, and the IL-10 gene as well. Importantly, our results demonstrate that E2, at physiological doses, stimulated the conversion of CD4+CD25- T cells into CD4+CD25+ T cells which exhibited enhanced Foxp3 and IL-10 expression in vitro. Such converted CD4+CD25+ T cells had similar regulatory function as naturally occurring Treg cells, as demonstrated by their ability to suppress naïve T cell proliferation in a mixed lymphocyte reaction. We also found that the estrogen receptor (ER) exist in the CD4+CD25- T cells and the conversion of CD4+CD25- T cells into CD4+CD25+ T cells stimulated by E2 could be inhibited by ICI182,780, a specific inhibitor of ER(s). This supports that E2 may directly act on CD4+CD25- T cells via ER(s). We conclude that E2 is a potential physiological regulatory factor for the peripheral development of CD4+CD25+ Treg cells during the implantation period in mice.

Summary Type I interferon (IFN), essential for spontaneous T cell priming against solid tumors, is generated through recognition of tumor DNA by STING. Interestingly, we observe that type I IFN is not elicited in animals with disseminated acute myeloid leukemia (AML). Further, survival of leukemia-bearing animals is not diminished in the absence of type I IFN signaling, suggesting that STING may not be triggered by AML. However, the STING agonist, DMXAA, induces expression of IFN-β and other inflammatory cytokines, promotes dendritic cell (DC) maturation, and results in the striking expansion of leukemia-specific T cells. Systemic DMXAA administration significantly extends survival in two AML models. The therapeutic effect of DMXAA is only partially dependent on host type I IFN signaling, suggesting that other cytokines are important. A synthetic cyclic dinucleotide that also activates human STING provided a similar anti-leukemic effect. These data demonstrate that STING is a promising immunotherapeutic target in AML.

Regulatory T (Treg) cells and the programmed death-1/programmed death ligand-1 (PD-1/PD-L1) pathway are both critical for maintaining peripheral tolerance to self antigens. A significant subset of Treg cells constitutively expresses PD-1, which prompted an investigation into the role of PD-1/PD-L1 interactions in Treg-cell development, function and induction in vivo. The phenotype and abundance of Treg cells was not significantly altered in PD-1-deficient mice. The thymic development of polyclonal and monospecific Treg cells was not negatively impacted by PD-1 deficiency. The suppressive function of PD-1−/− Treg cells was similar to their PD-1+/+ counterparts both in vitro and in vivo. However, in three different in vivo experimental settings, PD-1−/− conventional CD4+ T cells demonstrated a strikingly diminished tendency toward differentiation into peripherally induced Treg (pTreg) cells. Our results demonstrate that PD-1 is dispensable for thymic (tTreg) Treg-cell development and suppressive function, but is critical for the extrathymic differentiation of pTreg cells in vivo. These data suggest that antibody blockade of the PD-1/PD-L1 pathway may augment T-cell responses by acting directly on conventional T cells, and also by suppressing the differentiation of pTreg cells.

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Purpose This study investigated the effect of food additives, artificial sweeteners and domestic hygiene products on the gut microbiome and fibre fermentation capacity. Methods Faecal samples from 13 healthy volunteers were fermented in batch cultures with food additives (maltodextrin, carboxymethyl cellulose, polysorbate-80, carrageenan-kappa, cinnamaldehyde, sodium benzoate, sodium sulphite, titanium dioxide), sweeteners (aspartame-based sweetener, sucralose, stevia) and domestic hygiene products (toothpaste and dishwashing detergent). Short-chain fatty acid production was measured with gas chromatography. Microbiome composition was characterised with 16S rRNA sequencing and quantitative polymerase chain reaction (qPCR). Results Acetic acid increased in the presence of maltodextrin and the aspartame-based sweetener and decreased with dishwashing detergent or sodium sulphite. Propionic acid increased with maltodextrin, aspartame-based sweetener, sodium sulphite and polysorbate-80 and butyrate decreased dramatically with cinnamaldehyde and dishwashing detergent. Branched-chain fatty acids decreased with maltodextrin, aspartame-based sweetener, cinnamaldehyde, sodium benzoate and dishwashing detergent. Microbiome Shannon α-diversity increased with stevia and decreased with dishwashing detergent and cinnamaldehyde. Sucralose, cinnamaldehyde, titanium dioxide, polysorbate-80 and dishwashing detergent shifted microbiome community structure; the effects were most profound with dishwashing detergent (R2 = 43.9%, p = 0.008) followed by cinnamaldehyde (R2 = 12.8%, p = 0.016). Addition of dishwashing detergent and cinnamaldehyde increased the abundance of operational taxonomic unit (OTUs) belonging to Escherichia/Shigella and Klebsiella and decreased members of Firmicutes, including OTUs of Faecalibacterium and Subdoligranulum. Addition of sucralose and carrageenan-kappa also increased the abundance of Escherichia/Shigella and sucralose, sodium sulphite and polysorbate-80 did likewise to Bilophila. Polysorbate-80 decreased the abundance of OTUs of Faecalibacterium and Subdoligranulum. Similar effects were observed with the concentration of major bacterial groups using qPCR. In addition, maltodextrin, aspartame-based sweetener and sodium benzoate promoted the growth of Bifidobacterium whereas sodium sulphite, carrageenan-kappa, polysorbate-80 and dishwashing detergent had an inhibitory effect. Conclusions This study improves understanding of how additives might affect the gut microbiota composition and its fibre metabolic activity with many possible implications for human health.

Here we showed that ursolic acid (UA), a pentacyclic triterpene natural product, and its novel prodrug derivative US597 suppressed cancer cells adhesion, invasion and migration. This effect was accompanied by inhibition of focal adhesion signaling pathway including alterations in ICAM-1, VCAM-1, E-selectin, P-selectin, integrin α6β1, FAK, Src, paxillin and PTEN. While oral administration of UA or US597 increases survival rate of melanoma lung metastasis in C57BL/6 mice, US597 treatment extend the survival rate above that of UA. Immunohistochemical analysis revealed that US597 treatment regulates ICAM-1, a biomarker of metastasis. We did not detect side effects with US597 in mice such as weight loss, viscera tissues toxicity and blood cell abnormalities. Thus, UA and US597 are potential drug candidates for preventing cancer metastasis. Molecular and cellular study data suggest that UA and US597 modulate expression of cell adhesion molecules within focal adhesion signaling pathway leading to cancer cell motility.

It is proved that epidermal growth factor (EGF)-like factors mediate gonadotropin-induced rodent oocyte maturation via EGF receptor (EGFR). However, the detail kinetics and signal pathway between FSH and EGF/EGFR is not clear in large animals. In the present study, we investigated the roles of EGFR and protein kinase C (PKC) in FSH-induced porcine oocyte meiotic resumption. Porcine cumulus-oocyte complexes were cultured in NCSU37 medium containing 10% porcine follicular fluid and germinal vesicle breakdown (meiotic resumption) was detected after different treatments. The results showed that EGF-like factor amphiregulin (AR) and EGFR mRNA were expressed in porcine cumulus cells, but not oocytes. FSH significantly induced AR mRNA expression with maximum at 4 h and activated EGFR phosphorylation at 8 h. AR (1-100 ng/ml) dose-dependently induced meiosis resumption of porcine oocyte. The specific EGFR inhibitor, AG1478, but not AG43 (the inactive analog of AG1478), completely blocked FSH, EGF, and AR-induced oocyte meiotic resumption; the inhibitory effect of AG1478 on FSH action gradually decreased when the inhibitor was added at 6 h or later and disappeared when it was added at 11 h; EGF reversed the inhibitory effect on FSH when AG1478 was added within 6 h. FSH triggered porcine oocyte meiotic resumption (at 20 h) later than that of EGF and AR (at 18 h). All these results supported that endogenously produced EGFR activator(s), possibly AR (maximum at 4 h) and EGFR activation (began at 6 h and finished within 11 h), in cumulus cells is necessary for FSHinduced porcine oocyte meiotic resumption (began at 18 h). Furthermore, PKC activator PMA mimicked but PKC inhibitor chelerythrine chloride inhibited FSH action, and AG1478 also suppressed PMA-induced porcine oocyte meiotic resumption. These data together suggested that EGFR activation, by PKC signal pathway, participates in FSH-induced porcine oocyte meiotic resumption.

This study aimed to investigate the effect of circ_0000950/miR-103 network on regulating neuron apoptosis, neurite outgrowth and inflammation in Alzheimer's disease (AD). Cellular AD model of rat pheochromocytoma cell line PC12 cells and cellular AD model of rat cerebral cortex neurons were constructed, and the effect of circ_0000950 on apoptosis, neurite outgrowth and inflammation in both cellular AD models was determined through upregulation and knockdown of circ_0000950 expression by transfection. Compensation experiments and luciferase assay were further performed to validate the sponging effect of circ_0000950 on miR-103 as well as the mechanisms of circ_0000950/miR-103 on regulating apoptosis, neurite outgrowth and inflammation in both cellular AD models. Circ_0000950 reduced miR-103 expression and increased prostaglandin-endoperoxide synthase 2 (PTGS2) expression in both two cellular AD models. And circ_0000950 overexpression promoted neuron apoptosis, suppressed neurite outgrowth and elevated IL-1β, IL-6 and TNF-α levels compared with overexpression control, whereas circ_0000950 knockdown inhibited neuron apoptosis, enhanced neurite outgrowth and lowered IL-1β, IL-6 and TNF-α levels compared with shRNA control in both two cellular AD models. Compensation experiments along with luciferase reporter assay validated that circ_0000950 promoted cell apoptosis, suppressed neurite outgrowth and elevated inflammatory cytokines levels via directly sponging miR-103. In conclusion, circ_0000950 promotes neuron apoptosis, suppresses neurite outgrowth and elevates inflammatory cytokines levels through directly sponging miR-103 in AD.