Prednisone may induce immunologic tolerance by activating the functions of decidual immune cells in early pregnancy

Developmental programming: Impact of preconceptional and gestational exposure to a real-life environmental chemical mixture on maternal steroid, cytokine and oxidative stress milieus in sheep

BACKGROUND

Gestational exposure to environmental chemicals (ECs) is associated with adverse, sex-specific offspring health effects of global concern. As the maternal steroid, cytokine and oxidative stress milieus can have critical effects on pregnancy outcomes and the programming of diseases in offspring, it is important to study the impact of real-life EC exposure, i.e., chronic low levels of mixtures of ECs on these milieus. Sheep exposed to biosolids, derived from human waste, is an impactful model representing the ECs humans are exposed to in real-life. Offspring of sheep grazed on biosolids-treated pasture are characterized by reproductive and metabolic disruptions.

OBJECTIVE

To determine if biosolids exposure disrupts the maternal steroid, cytokine and oxidative stress milieus, in a fetal sex-specific manner.

METHODS

Ewes were maintained before mating and through gestation on pastures fertilized with biosolids (BTP), or inorganic fertilizer (Control). From maternal plasma collected mid-gestation, 19 steroids, 14 cytokines, 6 oxidative stress markers were quantified. Unpaired t-test and ANOVA were used to test for differences between control and BTP groups (n = 15/group) and between groups based on fetal sex, respectively. Correlation between the different markers was assessed by Spearman correlation.

RESULTS

Concentrations of the mineralocorticoids - deoxycorticosterone, corticosterone, the glucocorticoids - deoxycortisol, cortisol, cortisone, the sex steroids - androstenedione, dehydroepiandrosterone, 16-OH-progesterone and reactive oxygen metabolites were higher in the BTP ewes compared to Controls, while the proinflammatory cytokines IL-1β and IL-17A and anti-inflammatory IL-36RA were decreased in the BTP group. BTP ewes with a female fetus had lower levels of IP-10.

DISCUSSION

These findings suggest that pre-conceptional and gestational exposure to ECs in biosolids increases steroids, reactive oxygen metabolites and disrupts cytokines in maternal circulation, likely contributors to the aberrant phenotypic outcomes seen in offspring of BTP sheep - a translationally relevant precocial model.

Intravenous immunoglobulin and prednisolone to women with unexplained recurrent pregnancy loss after assisted reproductive technology treatment: a protocol for a randomised, double-blind, placebo-controlled trial

INTRODUCTION

Recurrent pregnancy loss (RPL), defined as two or more consecutive pregnancy losses in the first trimester, affects around 5% of fertile women. The underlying causes remain unknown in up to 60% of patients; however, most studies point at an immunological pathology in unexplained RPL, and therefore, an effective treatment may be immunomodulatory. This study aims to evaluate the effect of intravenous immunoglobulin (IVIg) and prednisolone on reproductive outcome and the immune system in women with unexplained RPL undergoing assisted reproductive technology treatment.

METHODS AND ANALYSIS

This randomised, placebo-controlled trial with double-blinded randomisation to two parallel arms evaluate if immunomodulatory (active) treatment is superior to placebo in increasing the chance of ongoing pregnancy assessed at nuchal translucency scan in gestational weeks (GW) 11-13 after embryo transfer (ET) in 74 RPL patients with ≥2 pregnancy losses as its primary objective. The active treatment consists of IVIg (one infusion preferably 1-5 days before ET and in GW 5, 6 and 7) and prednisolone (5 mg/day from first day of menstrual bleeding until ET and 10 mg/day from ET to GW 8+0) while the comparator consists of intravenous human albumin (5%) and placebo tablets. Allocation is concealed for participants, caregivers, and investigators until trial termination and is performed in a 1:1 ratio. The secondary objective is to evaluate treatment safety, and the tertiary objective is exploration of the association between treatment, reproductive outcome after ET, and the lymphocyte subset distribution in peripheral blood collected before and after intravenous infusion(s). Excess biological material is stored in a biobank for future research.

ETHICS AND DISSEMINATION

The North Denmark Region Committee on Health Research Ethics (N-20200066) approved this trial. The results will be published in peer-reviewed scientific journals and presented to relevant patient associations, at relevant academic conferences and to key stakeholders.

TRIAL REGISTRATION NUMBER

NCT04701034.

Analysis of Transcripts of Uncertain Coding Potential Using RNA Sequencing During the Preattachment Phase in Goat Endometrium

Transcripts of uncertain coding potential (TUCP) are part of long noncoding RNAs, which include short open reading frames and could be translated into small peptides. In recent years, a growing number of TUCPs has been implicated in multiple biological activities, such as embryogenesis and transcriptional regulation. However, the abundance of TUCPs and their roles in goat endometrium during pregnancy recognition (day 16) remain undocumented. In this study, bioinformatics analyses were conducted to identify the differentially expressed (DE) TUCPs between pregnant animals and corresponding nonpregnant controls. A total of 5551 TUCPs were identified; 114 TUCPs were DE in goat endometrium, of which 74 TUCPs were upregulated in pregnant endometrium, whereas 40 TUCPs were downregulated. The related genes of TUCP were predicted by using coexpression and colocalization methods. In summary, 419 genes were predicted by colocalization, and 9464 genes were predicted by coexpression. The kyoto encyclopedia of genes and genomes (KEGG) and gene ontology (GO) analysis showed that TUCPs, which are highly expressed in pregnant endometrium, were mainly associated with endometrial remodeling, nutrient synthesis, and transportation. However, TUCPs that were lowly expressed in pregnant endometrium were mainly associated with immune tolerance, which is necessary for the protection and development of the embryo in the uterus. These findings may be used for the comparative analysis of TUCP transcripts in endometrium and assist in the selection of applicable candidate genes associated with embryo implantation for further functional analyses.

Prednisone improves pregnancy outcome in repeated implantation failure by enhance regulatory T cells bias

OBJECTIVE

Repeated implantation failure (RIF) has been shown related to maternal immune imbalance. Many studies suggested that prednisone promoted the Th17/Treg balance shift to the direction of immune tolerance. Our study aimed to evaluate the role of prednisone in Th17/Treg balance and pregnancy outcome in RIF patients.

STUDY DESIGN AND MAIN OUTCOME MEASURES

Peripheral blood of healthy fertile controls and RIF patients were collected at the late proliferation phase. The population of Treg and Th17 cells, the expression of Foxp3 and RORC mRNA and the concentration of IL-17A, IL-23 and IL-10 were detected by flow cytometry, qRT-PCR and enzyme-linked immunosorbent assay. RIF patients were given oral prednisone 10 mg daily from the late proliferation phase of the cycle before FET. After one month of treatment, the above immune indicators were tested, and natural cycle frozen embryo transfer was performed.

RESULTS

The Treg cells proportion and IL-10 concentration in peripheral blood of RIF patients was lower than that of NF group, while the proportion of Th17 cells and concentration of proinflammatory cytokine were significantly higher. After prednisone treatment, the indicators related to immune tolerance increased significantly. Five out of 19 RIF patients were successful pregnancy after FET, in which, one had an early miscarriage and four live births. No pregnancy complications and fetal abnormalities were observed.

CONCLUSIONS

We report the beneficial effect of prednisone on RIF patients. The underlying mechanism may attribute to shift the Treg/Th17 immune balance to a Treg bias, and enhance embryo implantation, ultimately improve pregnancy outcomes.

Comparative Study of Immunomodulatory Agents to Induce Human T Regulatory (Treg) Cells: Preferential Treg-Stimulatory Effect of Prednisolone and Rapamycin

T regulatory (Treg) cells play a critical role in the maintenance of self-tolerance, as well as in inhibition of inflammation and exaggerated immune response against exogenous antigens. They develop in the thymus (tTreg cells) but also may be generated at the peripheral tissues, including tumor microenvironment (pTreg cells), or induced in vitro in the presence of transforming growth factor (TGF)-β (iTreg cells). Since tTreg cells constitute a minor fraction of peripheral blood lymphocytes in physiological conditions, an alternative way to obtain high number of functional Treg cells for therapeutic purposes is their generation in vitro from conventional T cells. In our studies, we compared effectiveness of several pharmacological agents with suggested immunomodulatory effects on Treg development (rapamycin, prednisolone, inosine pranobex, glatiramer acetate, sodium butyrate, and atorvastatin) to optimize Treg-inducing protocols. All but one (atorvastatin) immunomodulators augmented induction of polyclonal Treg cells in cultures. They were effective both in increasing the number of CD4⁺CD25^highFoxp3^high cells and Foxp3 expression. Rapamycin and prednisolone were found the most effective. Both drugs prolonged also phenotypic stability of Treg cells and induced fully active Treg cells in a functional assay. In the assay, prednisolone appeared superior versus rapamycin. The results, on the one hand, may be helpful in planning optimal protocols for generation of Treg cells for clinical application and, on the other hand, shed some light on mechanisms of the immunomodulatory activity of some tested agents observed in vivo.

Effect of miR-30e regulating NK cell activities on immune tolerance of maternal-fetal interface by targeting PRF1

AIM

Natural killer (NK) cells, as key regulatory cells, accumulate at the maternal-fetal interface in large numbers. This study explored the effect of miR-30e on regulating the activity and function of peripheral blood NK cells (PB-NK cells) and decidua NK cells (D-NK cells) by targeting PRF1 in immune tolerance of maternal-fetal interface.

METHODS

Expressions of miR-30e in PB and decidua tissues from 49 patients with recurrent spontaneous abortion and 52 normal pregnant women were measured using PCR. NK cells were isolated from PB and decidua tissues and identified by flow cytometry (FCM). In PB-NK cells and D-NK cells activated by IFN-α, expressions of miR-30e and PRF1 were determined by PCR and Western blot. Negative controls of miR-30e mimics/inhibitors and siRNA against PRF1 were transfected in PB-NK cells and D-NK cells. Expressions of miR-30e and PRF1 were determined and their relationship was verified. Expressions of KIR2DL1, NKp44, IFN-γ, TNF-α, IL-4 and IL-10 were determined by FCM. Cytotoxicity kit was used to identify the cytotoxicity of NK cells. PCR and ELISA were employed to measure expression of VEGF, Ang-2 and PGF in D-NK cells.

RESULTS

After activation by IFN-α, D-NK cells and PB-NK cells showed decreased miR-30e expression and increased PRF1 expression in normal non-pregnant women. PRF1 is a target gene of miR-30e and miR-30e negatively regulated PRF1 expression. The treatment of miR-30e mimics elevated KIR2DL1 expression and decreased NKp44 expression in PB-NK or D-NK cells. Moreover, up-regulation of miR-30e expression suppressed cytotoxicity, corresponding to increased expression of IL-4and IL-10 and reduced expression of IFN-γ and TNF-α in PB-NK and D-NK cells, as well as enhanced expression of VEGF, Ang-2 and PGF in D-NK cells. Transfection of miR-30e inhibitors could reverse the tendencies.

CONCLUSION

Up-regulated miR-30e can reduce the cytotoxicity of PB-NK cells and D-NK cells by targeting PRF1, whereby inhibiting Th1 tolerance phenotype and inducing Th2 immunodominance. miR-30e may be contributive to creating a micro-immune tolerance environment of maternal-fetal interface.