Messenger ribonucleic acid encoding interferon-inducible guanylate binding protein 1 is induced in human endometrium within the putative window of implantation

Decidualized endometrial stromal cells present with altered androgen response in PCOS

Hyperandrogenic women with PCOS show disrupted decidualization (DE) and placentation. Dihydrotestosterone (DHT) is reported to enhance DE in non-PCOS endometrial stromal cells (eSC_Ctrl); however, this has not been assessed in PCOS cells (eSC_PCOS). Therefore, we studied the transcriptome profile of non-decidualized (non-DE) and DE eSCs from women with PCOS and Ctrl in response to short-term estradiol (E2) and/or progesterone (P4) exposure with/without (±) DHT. The non-DE eSCs were subjected to E2 ± DHT treatment, whereas the DE (0.5 mM 8-Br-cAMP, 96 h) eSCs were post-treated with E2 and P4 ± DHT, and RNA-sequenced. Validation was performed by immunofluorescence and immunohistochemistry. The results showed that, regardless of treatment, the PCOS and Ctrl samples clustered separately. The comparison of DE vs. non-DE eSC_PCOS without DHT revealed PCOS-specific differentially expressed genes (DEGs) involved in mitochondrial function and progesterone signaling. When further adding DHT, we detected altered responses for lysophosphatidic acid (LPA), inflammation, and androgen signaling. Overall, the results highlight an underlying defect in decidualized eSC_PCOS, present with or without DHT exposure, and possibly linked to the altered pregnancy outcomes. We also report novel factors which elucidate the mechanisms of endometrial dysfunction in PCOS.

Generation of Progesterone-Responsive Endometrial Stromal Fibroblasts from Human Induced Pluripotent Stem Cells: Role of the WNT/CTNNB1 Pathway

Defective endometrial stromal fibroblasts (EMSFs) contribute to uterine factor infertility, endometriosis, and endometrial cancer. Induced pluripotent stem cells (iPSCs) derived from skin or bone marrow biopsies provide a patient-specific source that can be differentiated to various cells types. Replacement of abnormal EMSFs is a potential novel therapeutic approach for endometrial disease; however, the methodology or mechanism for differentiating iPSCs to EMSFs is unknown. The uterus differentiates from the intermediate mesoderm (IM) to form coelomic epithelium (CE) followed by the Müllerian duct (MD). Here, we successfully directed the differentiation of human iPSCs (hiPSCs) through IM, CE, and MD to EMSFs under molecularly defined embryoid body culture conditions using specific hormonal treatments. Activation of CTNNB1 was essential for expression of progesterone receptor that mediated the final differentiation step of EMSFs before implantation. These hiPSC-derived tissues illustrate the potential for iPSC-based endometrial regeneration for future cell-based treatments.

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We developed a molecularly defined system for differentiating hiPSCs to EMSFs

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hiPSC-derived EMSFs undergo decidualization in response to hormonal stimulation

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D14 embryoid bodies recapitulate the molecular signature of primary EMSFs

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The WNT/CTNNB1 pathway is required for induction of EMSF from hiPSCs

The major CD8 T cell effector memory subset in the normal and Chlamydia trachomatis-infected human endocervix is low in perforin

BACKGROUND

The local tissue microenvironment plays an important role in the induction, homing, maintenance and development of effector functions of T cells. Thus, site-specific differences in phenotypes of mucosal and systemic T cell populations have been observed. Chlamydia trachomatis most commonly infects the endocervix in women, yet little is known about Chlamydia-specific effector T cell immunity at this unique mucosal site. Our previous flow-cytometry-based study of cervical-cytobrush retrieved cells indicated that CD8 T cells are significantly increased in the C. trachomatis-infected human endocervix. The cytolytic function of CD8 T cells is important in the protective immunity against many intracellular pathogens, and requires the cytolytic granule perforin to facilitate the entry of other molecules that mediate the lysis of target cells. Determination of perforin expression of the CD8 T cell population in the endocervix would therefore provide insights on the granule-mediated cytolytic potential of these cells at this site.

RESULTS

Our histological data revealed that C. trachomatis-infected tissues have significantly higher numbers of CD3 and CD8 T cells compared to non-infected tissues (p<0.01), and that the majority of CD8+ cells do not express perforin in situ. A subsequent flow cytometric analysis of paired blood and endocervix-derived cells (n=16) revealed that while all the CD8 T cell subsets: naïve, effector memory (TEM), central memory (TCM) and terminally differentiated effector memory (TEMRA) can be found in the blood, the endocervix is populated mainly by the TEM CD8 T cell subset. Our data also showed that perforin expression in the TEM population is significantly lower in the endocervix than in the blood of C. trachomatis positive women (n=15; p<0.0001), as well as in C. trachomatis-negative individuals (n=6; p<0.05). Interestingly, our in vitro co-culture study suggests that the exposure of HeLa 229 cervical epithelial cells to IFN gamma could potentially induce a decrease in perforin content in CD8 TEM cells in the same microenvironment.

CONCLUSIONS

The low perforin content of CD8 TEM cells in the endocervix, the local site of C. trachomatis infection in women, may reflect the unique immunological environment that balances immune protection against sexually transmitted infections and immune- tolerance to support conception.

Cytokine and progesterone receptor interplay in the regulation of MUC1 gene expression

Mucin 1 (MUC1), a transmembrane mucin expressed at the apical surface of uterine epithelia, is a barrier to microbial infection and enzymatic attack. MUC1 loss at implantation sites appears to be required to permit embryo attachment and implantation in most species. MUC1 expression is regulated by progesterone (P) and proinflammatory cytokines, including TNFα and interferon γ (IFNγ). TNFα and IFNγ are highly expressed in uterine tissues under conditions where MUC1 expression is also high and activate MUC1 expression via their downstream transcription factors, nuclear factor (NF) κB and signal transducers and activators of transcription. P receptor (PR) regulates MUC1 gene expression in a PR isoform-specific fashion. Here we demonstrate that interactions among PR isoforms and cytokine-activated transcription factors cooperatively regulate MUC1 expression in a human uterine epithelial cell line, HES. Low doses of IFNγ and TNFα synergistically stimulate MUC1 promoter activity, enhance PRB stimulation of MUC1 promoter activity and cooperate with PRA to stimulate MUC1 promoter activity. Cooperative stimulation of MUC1 promoter activity requires the DNA-binding domain of the PR isoforms. MUC1 mRNA and protein expression is increased by cytokine and P treatment in HES cells stably expressing PRB. Using chromatin immunoprecipitation assays, we demonstrate efficient recruitment of NFκB, p300, SRC3 (steroid receptor coactivator 3), and PR to the MUC1 promoter. Collectively, our studies indicate a dynamic interplay among cytokine-activated transcription factors, PR isoforms and transcriptional coregulators in modulating MUC1 expression. This interplay may have important consequences in both normal and pathological contexts, e.g. implantation failure and recurrent miscarriages.

Guanylate-binding protein-1 is expressed at tight junctions of intestinal epithelial cells in response to interferon-gamma and regulates barrier function through effects on apoptosis

Guanylate-binding protein-1 (GBP-1) is an interferon inducible large GTPase involved in endothelial cell proliferation and invasion. In this report, expression and function of GBP-1 were investigated in vitro in intestinal epithelia after exposure to interferon-gamma and in human colonic mucosa from individuals with inflammatory bowel disease (IBD). Interestingly, in contrast to other epithelia, GBP-1 distributed to the plasma membrane in intestinal epithelial cells where it colocalized with the tight junction protein coxsackie- and adenovirus receptor. In addition, expression of GBP-1 was upregulated in colonic epithelia of individuals with IBD. Downregulation of GBP-1 by siRNA resulted in enhanced permeability that correlated with increased apoptosis. Indeed, inhibition of caspase activity prevented the inhibition of barrier formation induced by the loss of GBP-1. These data suggest that GBP-1 is a novel marker of intestinal mucosal inflammation that may protect against epithelial apoptosis induced by inflammatory cytokines and subsequent loss of barrier function.

Guanylate-binding protein-1 expression is selectively induced by inflammatory cytokines and is an activation marker of endothelial cells during inflammatory diseases

During angiogenesis and inflammatory processes, endothelial cells acquire different activation phenotypes, whose identification may help in understanding the complex network of angiogenic and inflammatory interactions in vivo. To this goal we investigated the expression of the human guanylate-binding protein (GBP)-1 that is highly induced by inflammatory cytokines (ICs) and, therefore, may characterize IC-activated cells. Using a new rat monoclonal antibody raised against GBP-1, we show that GBP-1 is a cytoplasmic protein and that its expression in endothelial cells is selectively induced by interferon-gamma, interleukin-1alpha, interleukin-1beta, or tumor necrosis factor-alpha, but not by other cytokines, chemokines, or growth factors. Moreover, we found that GBP-1 expression is highly associated with vascular endothelial cells as confirmed by the simultaneous detection of GBP-1 and the endothelial cell-associated marker CD31 in a broad range of human tissues. Notably, GBP-1 expression was undetectable in the skin, but it was highly induced in vessels of skin diseases with a high-inflammatory component including psoriasis, adverse drug reactions, and Kaposi's sarcoma. These results indicate that GBP-1 is a novel cellular activation marker that characterizes the IC-activated phenotype of endothelial cells.