Embryonal carcinomas (ECs) and seminomas are testicular germ cell tumors. ECs display expression of SOX2, while seminomas display expression of SOX17. In somatic differentiation, SOX17 drives endodermal cell fate. However, seminomas lack expression of endoderm markers, but show features of pluripotency. Here, we use chromatin immunoprecipitation sequencing to report and compare the binding pattern of SOX17 in seminoma-like TCam-2 cells to SOX17 in somatic cells and SOX2 in EC-like 2102EP cells. In seminoma-like cells, SOX17 was detected at canonical (SOX2/OCT4), compressed (SOX17/OCT4) and noncomposite SOX motifs. SOX17 regulates TFAP2C, PRDM1 and PRDM14, thereby maintaining latent pluripotency and suppressing somatic differentiation. In contrast, in somatic cells canonical motifs are rarely bound by SOX17. In sum, only 12% of SOX17-binding sites overlap in seminoma-like and somatic cells. This illustrates that binding site choice is highly dynamic and cell type specific. Deletion of SOX17 in seminoma-like cells resulted in loss of pluripotency, marked by a reduction of OCT4 protein level and loss of alkaline phosphatase activity. Furthermore, we found that in EC-like cells SOX2 regulates pluripotency-associated genes, most likely by partnering with OCT4. In conclusion, SOX17 (in seminomas) functionally replaces SOX2 (in ECs) to maintain expression of the pluripotency cluster. 相似文献
Skin injury can trigger formation of new lesions in psoriasis (Koebner phenomenon). The mechanisms through which injury exacerbates psoriasis are unclear. During wound repair, epidermal keratinocytes are activated and produce abundant IL‐36γ, further promoting the skin inflammation. IL‐17A is the cornerstone cytokine in the pathogenesis of psoriasis. We sought to investigate the effects of IL‐17A on injury‐induced keratinocyte activation and IL‐36γ production. Here, we demonstrated that dsRNA released from necrotic keratinocytes induced the expression of IL‐36γ. Silencing of TLR3 by siRNA decreased the IL‐36γ induction by necrotic keratinocyte supernatant. Co‐stimulation with dsRNA and IL‐17A synergistically increased the expression of IL‐36γ and other proinflammatory mediators (CCL20, CXCL8, DEFB4 and LCN2) in keratinocytes. The synergistic effects were not dependent on TLR3 upregulation, TNF receptor signalling and mRNA stabilization. Co‐stimulation with dsRNA and IL‐17A resulted in an accumulation of IκBζ. The synergistic upregulation of IL‐36γ and proinflammatory mediators were inhibited by IκBζ siRNA. Co‐stimulation with IL‐17A and poly(I:C) markedly activated the p38 MAPK and NF‐κB pathway, compared with poly(I:C). Blockade of p38 MAPK and NF‐κB suppressed dsRNA/IL‐17A–mediated IκBζ and IL‐36γ induction. These findings demonstrated that IL‐17A synergistically enhanced the dsRNA‐mediated IL‐36γ production through a p38 MAPK‐, NF‐κB–, and IκBζ‐dependent mechanism. 相似文献
Background and study aimsNon-invasive biomarkers of inflammatory bowel diseases (IBD) are of critical importance. Here, we evaluated the S100A8 and S100A9 mRNA expression, as the heterodimers of calprotectin, in the blood leucocytes of IBD patients to find how their expression associates with the disease characteristics.Patients and methodsIn this cross-sectional study, 59 IBD patients and 30 healthy subjects were included. The flare and remission phases of disease were identified in 46 and 13 patients, respectively. Blood leucocytes were isolated, and the S100A8 and S100A9 mRNA expression were evaluated in the isolated leucocytes using relative quantification real-time PCR.ResultsThe mean S100A8 and S100A9 mRNA expression were significantly higher in IBD patients than in the controls (p = 0.03 and p = 0.02, respectively). The mean S100A8 and S100A9 mRNA expression were significantly higher in the flare phase of the disease compared with the remission phase (p = 0.01 and p = 0.007, respectively). S100A8 distinguished IBD patients from controls with the sensitivity and specificity of 73% and 64%, and flare phase of disease from remission with the sensitivity and specificity of 67% and 62%. On the other hand, S100A9 distinguished IBD patients from controls with the sensitivity and specificity of 81% and 70%, and flare phase of disease from remission with the sensitivity and specificity of 68% and 64%.ConclusionThe S100A8 and S100A9 mRNA are differentially expressed in blood leucocytes of IBD patients compared to healthy controls as well as active versus quiescent disease. Thus, they can be potentially used as a blood-based biomarker in the monitoring of IBD. 相似文献
Background: Endplate inflammation remains a difficult disease to treat, in part due to its unclear pathology. Previous experiments showed that patients with idiopathic inflammation presented a systemic upregulation of Th17 cells. Here, we investigated how this change might affect the inflammatory environment in endplate inflammation.
Methods: Peripheral blood was obtained from patients and healthy controls, and Th17 cells were examined.Results: Th17 cells significantly increased the differentiation of CD11c+ and DC-SIGN+ dendritic cells (DCs) from circulating monocytes in the absence of exogenous stimulation as well as in the presence of LPS stimulation. Th17 cells also increased CD80 and CD86 expression by DCs. Importantly, although Th17 cells from both healthy controls and patients with endplate inflammation could induce CD11c, DC-SIGN, CD80, and CD86 expression, Th17 cells from patients with endplate inflammation showed significantly more potent capacity. Both contact-dependent and IL-17-dependent mechanisms were employed by Th17 cells, since blocking cell-to-cell contact significantly inhibited Th17-mediated differentiation of CD11c+ DCs, and neutralization of IL-17 reduced the expression of CD80 and CD86. Strikingly, DCs following incubation with Th17 cells, but not the DCs derived directly from monocytes without Th17 cells, could significantly promote the expression of IL-17 from naive CD4+ T cells.
Conclusions: These results demonstrated that Th17 cells from patients with endplate inflammation could potently induce the differentiation and activation of DCs that preferentially promoted IL-17 response in a positive feedback loop. 相似文献