Gut microbiota-derived compounds are pivotal in modulating host immunity by regulating the functions of various key innate and adaptive immune cells. Epstein-Barr virus-induced gene 3 (EBI3) serves as Show more
Gut microbiota-derived compounds are pivotal in modulating host immunity by regulating the functions of various key innate and adaptive immune cells. Epstein-Barr virus-induced gene 3 (EBI3) serves as the beta subunit shared by the heterodimeric cytokines interleukin (IL)-27 and IL-35. Both these cytokines have been documented to inhibit the development of T helper 2 (Th2) and T helper 17 (Th17) cells, while enhancing the function of regulatory T cells (Tregs). EBI3, itself, has also been shown to regulate cell-mediated immune responses. Despite their critical roles in maintaining immune homeostasis, there is a significant lack of robust, high-throughput-compatible assays to evaluate the secretion of IL-27, IL-35, or EBI3. In this study, we detail the development of a novel amplified luminescent proximity homogeneous assay (AlphaLISA™) to quantify EBI3 secretion by tolerogenic dendritic cells. We utilized this assay to screen a library of 9739 small proteins derived from the human gut microbiota to identify compounds that could stimulate EBI3 secretion. Our findings revealed the immunoregulatory potential of VAC18, an unknown protein from Fusicatenibacter saccharivorans (Clostridiumcluster XIVa) which significantly induces the secretion of both EBI3 and IL-27. This is the first study to demonstrate the effect of gut microbiota derived peptides on the balanced secretion of EBI3 and IL-27. Show less
The epithelial to mesenchymal transition (EMT) has been implicated in the development of adenomyosis, along with dysregulated immune responses. Inflammation potentially induces Notch signaling, which Show more
The epithelial to mesenchymal transition (EMT) has been implicated in the development of adenomyosis, along with dysregulated immune responses. Inflammation potentially induces Notch signaling, which could promote this EMT. The objective of this study was to investigate the involvement of immune cells and Notch1-mediated EMT in the development of adenomyosis. Adenomyosis was induced in 18 CD-1 mice by neonatal oral administration of tamoxifen (TAM group), while 18 neonates received vehicle only (Control group). Their uteri were sampled at 30, 60 or 90 days of age. Immune cell markers (Cd45, Ly6c1, Cd86, Arginine1, Cd19, Cd4, Cd8), Notch1 and its target genes (Hey1, Hey2, Hes1, Hes5) and biomarkers of EMT (E-Cadherin, Vimentin, Tgfb, Snail1, Slug, Snail3) were analyzed by quantitative RT-PCR and immunohistochemistry. Activated-Notch1 protein was measured by western blot. Aberrant expression of immune cell markers was observed in the uteri of mice as they developed adenomyosis. The expression of inflammatory cell markers, notably M1 macrophages and natural killer cells, was increased from Day 30 in the TAM group compared to controls, followed by an increase in the Cd4 marker (T cells) at Day 60. Conversely, expression of the Cd19 marker (B cells) was significantly reduced at all of the stages studied. Notch1 signaling was also highly activated compared to controls at Day 30 and Day 60. Concomitantly, the levels of several markers for EMT were also higher. Therefore, the activation of Notch1 coincides with aberrant expression of immune and EMT markers in the early development of adenomyosis. Show less