IL-27 deficiency inhibits proliferation and invasion of trophoblasts via the SFRP2/Wnt/ß-catenin pathway in fetal growth restriction.

Background: Fetal growth restriction (FGR) is characterized by restricted fetal growth and dysregulated placental development. The etiology and pathogenesis still remain elusive. IL-27 shows multiple roles in regulating various biological processes, however, how IL-27 involves in placentation in FGR pregnancy hasn't been demonstrated. Methods: The levels of IL-27 and IL-27RA in FGR and normal placentae were determined by immunohistochemistry, western blot and RT-PCR. HTR-8/SVneo cells and Il27ra-/- murine models have been adopted to evaluate the effects of IL-27 on the bio-functions of trophoblast cells. GO enrichment and GSEA analysis were performed to explore the underlying mechanism. Findings: IL-27 and IL-27RA was lowly expressed in FGR placentae and administration of IL-27 on HTR-8/SVneo could promote its proliferation, migration and invasion. Comparing with wildtypes, Il27ra-/- embryos were smaller and lighter, and the placentae from which were poorly developed. In mechanism, the molecules of canonical Wnt/ß-catenin pathway (CCND1, CMYC, SOX9) were downregulated in Il27ra-/- placentae. In contrast, the expression of SFRP2 (negative regulator of Wnt) was increased. Overexpression of SFRP2 in vitro could impair trophoblast migration and invasion capacity. Interpretation: IL-27/IL-27RA negatively regulates SFRP2 to activate Wnt/ß-catenin, and thus promotes migration and invasion of trophoblasts during pregnancy. However, IL-27 deficiency may contribute to the development of FGR by restricting the Wnt activity.

Impaired IL-27 signaling aggravates macrophage senescence and sensitizes premature ovarian insufficiency induction by high-fat diet.

Premature ovarian insufficiency (POI) critically affects female reproductive health, with obesity being a significant and recognized risk factor. Interleukin-27 (IL-27), known for its role in immune modulation and inflammation, has garnered attention in metabolic syndrome research. Nonetheless, the role of these immunometabolic factors on the initiation of POI remains to be unraveled. Our investigation delves into the influence of impaired IL-27 signaling on POI induction, particularly under the challenge of a high-fat diet (HFD). We analyzed patients' serum profiles and established a correlation of increased serum triglycerides with decreased IL-27 levels in POI cases. Experiments on C57BL/6 mice lacking the IL-27 receptor alpha (Il27ra-/-) revealed that when subjected to HFD, these mice developed hallmark POI symptoms. This includes escalated lipid deposition in both liver and ovarian tissues, increased ovarian macrophages cellular aging, and diminished follicle count, all pointing to compromised ovarian function. These findings unveil a novel pathway wherein impaired IL-27 signaling potentiates the onset of POI in the presence of HFD. Understanding the intricate interplay between IL-27, metabolic alterations, and immune dysregulation sheds light on potential therapeutic avenues for managing POI, offering hope for improved reproductive health outcomes.

IL-27 promotes decidualization via the STAT3-ESR/PGR regulatory axis.

Appropriate decidualization is of great importance for embryo implantation, placental development and successful pregnancy. Although it has been well-acknowledged that decidualization relies on activation of progesterone-mediated signaling pathway, the exact mechanisms have not been elucidated. Here, we demonstrated that both IL-27 and IL27RA were highly expressed in decidua than those in endometrium during secretory phase. Estrogen plus progesterone significantly upregulated the expression of IL-27 and IL-27RA in endometrium stromal cells (ESCs). In addition, inhibiting IL-27 signaling with IL-27 neutralization antibody (anti-IL-27) suppressed the expression of decidualization-related molecules, receptors of estrogen (gene coded by ESR) and progesterone (PGR) induced by cAMP or estrogen plus progesterone. Similar results were obtained from Il27ra-/- (knockout of Il27ra) female mice. Moreover, knockout of Il27ra did not affect the estrus cycle and folliculogenesis in mice but reduced implantation rate with the impairing decidualization. Mechanistically, IL-27 upregulated the expression of ESR1, ESR2 and PGR in ESCs and DSCs, as well as the phosphorylation level of STAT3. In the presence of estrogen plus progesterone, treatment with ESCs with anti-IL-27 inhibited the activation of STAT3. Also, the expression of ESR, PGR was decreased in Il27ra-/- mice. In conclusion, these findings demonstrate that IL-27 upregulated by estrogen and progestogen promotes decidualization possibly through a STAT3-dominant pathway.

IL-27/IL-27RA signaling may modulate inflammation and progression of benign prostatic hyperplasia via suppressing the LPS/TLR4 pathway.

BACKGROUND: Benign prostatic hyperplasia (BPH) is the most common urologic disease affecting aging men. The pathogenesis of BPH is multi-factorial, and chronic inflammation (CI) might be the central mechanism. Interleukin (IL)-27 signaling has been suggested as a modulator in autoimmune and inflammatory conditions. In this study, we used microarray experiments to analyze gene expression and molecular phenotypic associated with BPH progression, with a particular focus on CI and IL-27/IL-27RA signaling, and verified the microarray data in cell biology experiments. METHODS: Thirty BPH patients' specimens and clinical parameters were analyzed. BPH patients were divided into two groups based on the average prostate volume (41.5 mL): group 1, ≤40 mL; and group 2, >40 mL. Microarray experiments were conducted to identify differentially expressed genes (DEGs) by applying appropriate biostatistics to normalize and analyze the dataset. The candidate gene (IL27RA) was validated by quantitative reverse transcriptase-PCR (qRT-PCR) and immunohistochemistry (IHC). The interaction of IL27RA with genes involved in canonical inflammation-associated pathways was investigated by cell biology experiments. RESULTS: Eighty-three percent of BPH specimens contained inflammatory infiltrates, and the predominant type was CI. The serum PSA levels and prevalence of CI were higher in group 2. Microarray experiments identified 361 DEGs between these 2 groups. IL27RA was down-regulated and associated with prominent CI in BPH tissues of group 2. Validated by qRT-PCR and IHC, the results showed IL-27RA might modulate CI and progression of BPH. Thus, we investigated the interaction of IL27RA with TLR4, IL6, and IL8, which were involved in inflammation-associated pathways. We found the activation of IL-27RA after IL-27 treatment led to phosphorylation of STAT1 and STAT3 in prostate epithelial cells. By comparative treatments with lipopolysaccharide (LPS), IL-27, or combination, we found that IL-27/IL-27RA signaling suppressed the production of inflammatory cytokines, IL-6 and IL-8, induced by LPS/TLR4 pathway. CONCLUSIONS: Our study revealed that down-regulation of IL27RA in prostate tissue was associated with higher prevalence of CI and BPH progression. IL-27/IL-27RA signaling suppressed the LPS/TLR4 pathway. We conclude the IL-27/IL-27RA signaling might modulate CI and provide potential therapeutic strategies to prevent BPH progression.

Interleukin-27 Is Essential for Type 1 Diabetes Development and Sjögren Syndrome-like Inflammation.

Human genetic studies implicate interleukin-27 (IL-27) in the pathogenesis of type 1 diabetes (T1D), but the underlying mechanisms remain largely unexplored. To further define the role of IL-27 in T1D, we generated non-obese diabetic (NOD) mice deficient in IL-27 or IL-27Rα. In contrast to wild-type NOD mice, both NOD.Il27-/- and NOD.Il27ra-/- strains are completely resistant to T1D. IL-27 from myeloid cells and IL-27 signaling in T cells are critical for T1D development. IL-27 directly alters the balance of regulatory T cells (Tregs) and T helper 1 (Th1) cells in pancreatic islets, which in turn modulates the diabetogenic activity of CD8 T cells. IL-27 also directly enhances the effector function of CD8 T cells within pancreatic islets. In addition to T1D, IL-27 signaling in T cells is also required for lacrimal and salivary gland inflammation in NOD mice. Our study reveals that IL-27 contributes to autoimmunity in NOD mice through multiple mechanisms and provides substantial evidence to support its pathogenic role in human T1D.

Enhanced LPS-induced activation of IL-27 signalling in sarcoidosis.

RATIONALE: Granulomas in sarcoidosis have recently been described as containing Interleukin (IL)-27, one of the members of the IL-12 family of cytokines, which also includes IL-35. Levels of these cytokines and the IL-27 receptor subunits were hypothesised to differ between patients with sarcoidosis compared to healthy controls in peripheral blood. METHODS: Using a cross-sectional study design, plasma and peripheral blood mononuclear cells (PBMC) were collected from patients and control subjects. Protein and mRNA (in PBMC) levels for IL-27 and IL-35 (IL27, EBI3, IL12A subunits) as well as IL-27 receptor (IL6ST and IL27RA subunits) were assessed spontaneously and following direct (LPS) and indirect (anti-CD3/28 activation beads) macrophage stimulation using RT- PCR, ELISA and flow cytometry. RESULTS: Following stimulation with LPS, PBMC of patients with sarcoidosis displayed significantly enhanced expression of IL27 and EBI3 mRNA (p = 0.020 and p = 0.037 respectively) compared to PBMCs from healthy controls. There was also significantly enhanced production of IL-27 by PBMC from patients with sarcoidosis compared to healthy controls in response to LPS stimulation (p = 0.027). IL6ST mRNA and IL6ST protein were significantly lower in patients with sarcoidosis (mRNA p = 0.0002; MFI p = 0.0015) whilst IL27RA protein levels were significantly higher in patients with sarcoidosis compared to healthy controls (MFI p < 0.0001). Plasma IL-35 protein levels did not differ between control and sarcoidosis subjects (p = 0.23). CONCLUSION: These results suggest there may be exaggerated activation of IL-27 signalling in response to LPS in sarcoidosis.

IL27 controls skin tumorigenesis via accumulation of ETAR-positive CD11b cells in the pre-malignant skin.

Establishment of a permissive pre-malignant niche in concert with mutant stem are key triggers to initiate skin carcinogenesis. An understudied area of research is finding upstream regulators of both these triggers. IL27, a pleiotropic cytokine with both pro- and anti-inflammatory properties, was found to be a key regulator of both. Two step skin carcinogenesis model and K15-KRASG12D mouse model were used to understand the role of IL27 in skin tumors. CD11b-/- mice and small-molecule of ETAR signaling (ZD4054) inhibitor were used in vivo to understand mechanistically how IL27 promotes skin carcinogenesis. Interestingly, using in vivo studies, IL27 promoted papilloma incidence primarily through IL27 signaling in bone-marrow derived cells. Mechanistically, IL27 initiated the establishment of the pre-malignant niche and expansion of mutated stem cells in K15-KRASG12D mouse model by driving the accumulation of Endothelin A receptor (ETAR)-positive CD11b cells in the skin-a novel category of pro-tumor inflammatory identified in this study. These findings are clinically relevant, as the number of IL27RA-positive cells in the stroma is highly related to tumor de-differentiation in patients with squamous cell carcinomas.