Introduction: Young patients receiving chemotherapy occasionally face infertility and premature ovarian failure (POF). Numerous investigations reported that adipose-derived stem cells (ADSCs) transplantation could ameliorate the structure and function of injured tissues. The aim of this study was to explore the therapeutic efficacy of ADSC transplantation for chemotherapy-induced ovarian damage. Methods: Female mice were injected intraperitoneally with 50 mg/kg cyclophosphamide (CTX). After 15 consecutive days of injection, ADSCs were transplanted either directly into bilateral ovaries or via intravenous injection, and the ovaries were excised after either 1 week or 1 month of treatment. The follicles were counted and categorized, and ovarian histologic sections were stained for TUNEL. Ovarian function was evaluated by monitoring ovulation. ADSC tracking, microarray analyses, and real-time polymerase chain reaction (PCR) were used to assess the inner mechanism of injury and repair. Results: The ovarian function of mice exposed to CTX injection improved after ADSC transplantation. The population of follicles at different stages and ovulation significantly increased after the treatment. Immunofluorescence revealed reduced TUNEL staining. The tracking of ADSCs revealed that these cells did not directly differentiate into the follicle component. Microarray analyses indicated that changes in different groups of genes might affect follicle formation or ovulation. Conclusions: ADSC transplantation improved ovarian function. Our results suggest a potential mechanism for ADSC therapy.

Maternal-fetal immune-tolerance occurs throughout the whole gestational trimester, thus a mother can accept a genetically distinct fetus without immunological aggressive behavior. HLA-G, one of the non-classical HLA class I molecules, is restricted-expression at extravillous trophoblast. It can concordantly interact with various kinds of receptors mounted on maternally immune cells residing in the uterus (e.g. CD4+ T cells, CD8+ T cells, natural killer cells, macrophages, and dendritic cells) for maintaining immune homeostasis of the maternal-fetus interface. HLA-G is widely regarded as the pivotal protective factor for successful pregnancies. In the past 20 years, researches associated with HLA-G have been continually published. Indeed, HLA-G plays a mysterious role in the mechanism of maternal-fetal immune-tolerance. It can also be ectopically expressed on tumor cells, infected sites and other pathologic microenvironments to confer a significant local tolerance. Understanding the characteristics of HLA-G in immunologic tolerance is not only beneficial for pathological pregnancy, but also helpful to the therapy of other immune-related diseases, such as organ transplant rejection, tumor migration, and autoimmune disease. In this review, we describe the biological properties of HLA-G, then summarize our understanding of the mechanisms of fetomaternal immunologic tolerance and the difference from transplant tolerance. Furthermore, we will discuss how HLA-G contributes to the tolerogenic microenvironment during pregnancy. Finally, we hope to find some new aspects of HLA-G in fundamental research or clinical application for the future.

What changes in the mitochondria of human mural granulosa cells (mGCs) with maternal aging? The mitochondrial membrane potential (MMP) and the ability of oxidative phosphorylation (OXPHOS) of mGCs declines with reproductive aging, accompanied with more abnormal mitochondria. Mitochondria play an important role in the dialogue between the mGCs and oocytes. However, the underlying mechanism of mitochondrial dysfunction in mGCs in aging is still poorly understood. In total, 149 infertile women underwent IVF in the ART Centre of the Chinese PLA General Hospital, China from September 2016 to May 2017. Two age groups were investigated: the young group (<38 years old) and the old group (≥38 years old). The mitochondrial ultrastructure of mGCs was observed by transmission electron microscopy, and real-time quantitative polymerase chain reaction was applied to quantify the mitochondrial DNA (mtDNA) copy number, 4977-bp deleted DNA and mRNA expression of mitochondrial ATP synthases ATP5A1 and ATP5I. MMP was detected by flow cytometry and fluorescence microscopy, respectively. Reactive oxygen species (ROS) was tested by flow cytometry. A luminometer was used to measure the ATP levels and western blot to analyse the OXPHOS complex. In the young group, mitochondria were mostly round or oval, with a few intact parallel tubular–vesicular cristae and homogenous matrix density, while elongated mitochondria were mainly observed in the old group, which had numerous cristae and more high-density matrix particles. Abnormal mitochondria were more common in aging women (P = 0.012). mtDNA relative copy number was positively correlated with maternal age (r = 0.294, P = 0.009) and we found no one with 4977-bp deleted mitochondria. JC-1 (dye used as an indicator of MMP) ratio in the old group was significantly lower than the young group (3.01 ± 0.21 vs 3.85 ± 0.27, P = 0.033). Intracellular ROS levels between the groups did not differ significantly (P = 0.191). The intracellular ATP level in the young group was 1.75-fold higher than that of the advanced-age group (7.17 ± 1.16 vs 4.15 ± 0.60, P = 0.025). The protein expression of ATP5A1, as one of five proteins of OXPHOS, decreased with aging (P < 0.001). ATP5A1 mRNA expression was negatively correlated with aging (r = −0.341, P = 0.012). The quantity of mGCs from some individual patient, especially an advanced-age individual, was small, which cannot meet the demands of all the detections. mGCs dysfunction with aging is mainly linked to impaired mitochondrial function, especially OXPHOS function. Improving the OXPHOS ability in mGCs should be the focus in resolving infertility among advanced age women and making mGCs the proper mitochondria donor cells in the autologous mitochondria transplantation to oocytes. This work was supported by the grants of the National High Technology Research and Development Program of China, 863 Program No. SS2015AA020402, and the Key Projects of Military Medical Research, No. BWS11J058. There were no competing interests.

Elder women suffer from low or loss of fertility because of decreasing oocyte quality as maternal aging. As energy resource, mitochondria play pivotal roles in oocyte development, determining oocyte quality. With advanced maternal age, increased dysfunctions emerge in oocyte mitochondria, which decrease oocyte quality and its developmental potential. Mitochondria supplement as a possible strategy for improving egg quality has been in debate due to ethnic problems. Heterogeneity is an intractable problem even transfer of germinal vesicle, spindle, pronuclei or polar body is employed. We proposed that the autologous adipose tissue-derived stem cell (ADSC) mitochondria could improve the fertility in aged mice. We found that autologous ADSC mitochondria could promote oocyte quality, embryo development and fertility in aged mice, which may provide a promising strategy for treatment of low fertility or infertility in elder women.

Understanding human endometrial dynamics in the establishment of endometrial receptivity remains a challenge, which limits early diagnosis and treatment of endometrial-factor infertility. Here, we decode the endometrial dynamics of fertile women across the window of implantation and characterize the endometrial deficiency in women with recurrent implantation failure. A computational model capable of both temporal prediction and pattern discovery is used to analyze single-cell transcriptomic data from over 220,000 endometrial cells. The time-series atlas highlights a two-stage stromal decidualization process and a gradual transitional process of the luminal epithelial cells across the window of implantation. In addition, a time-varying gene set regulating epithelium receptivity is identified, based on which the recurrent implantation failure endometria are stratified into two classes of deficiencies. Further investigation uncovers a hyper-inflammatory microenvironment for the dysfunctional endometrial epithelial cells of recurrent implantation failure. The holistic characterization of the physiological and pathophysiological window of implantation and a computational tool trained on this temporal atlas provide a platform for future therapeutic developments.