Rie Fukuhara

Uterine and circulating natural killer cells and their roles in women with recurrent pregnancy loss, implantation failure and preeclampsia

The regulation of uterine and circulating peripheral blood natural killer (NK) cells has been associated with reproductive conditions including recurrent pregnancy loss (RPL), implantation failure and preeclampsia. Natural cytotoxicity receptors (NCRs) are unique markers that regulate NK cell cytotoxicity and cytokine production. The role of NCRs in reproductive events has not yet been fully characterized. There is an NK1 (Type 1) shift in peripheral blood NK cells in non-pregnant women prone to RPL and implantation failure. The different profile of NCR expression in endometrial or aborted decidual NK cells suggests the presence of abnormal regulation of NK cells in women with reproductive failure. Women with a history of RPL and preeclampsia carry immunological abnormalities of NCRs on peripheral blood NK cells during pregnancy. Evaluation of NKp46 on peripheral blood NK cells may be applicable for the prediction of preeclampsia. The lower expression of NKp46(+) NK cells in women with preeclampsia may account for the higher production of NK1 cytokines - known as the NK1 shift - in pregnant women with preeclampsia. In this review, the expression of NCRs in peripheral blood NK cells and endometrial or decidual NK cells is discussed in relation to reproductive failure.

An investigation of the potential effect of vacuoles in human sperm on DNA damage using a chromosome assay and the TUNEL assay

BACKGROUND The aims of this study were to establish whether individual differences exist in the frequency and size of vacuoles found in human sperm and to ascertain whether such vacuoles are involved in causing DNA damage. METHODS Morphologically normal sperm were obtained from 15 IVF and 2 ICSI patients and 3 fertile donors. (i) Sperm heads were analyzed for the presence of vacuoles under a 1000× differential interference contrast microscope. (ii) In three patients and two donor samples, structural chromosomal damage was evaluated in normal sperm containing large vacuoles and selected at 1000× magnification for injection into mouse oocytes. (iii) In 10 patients and two donor samples, confocal laser microscopy detected DNA damage in sperm-exhibiting large vacuoles and stained with an in situ cell death detection kit. RESULTS (i) Vacuoles were observed in almost all normal sperm from patient and donor ejaculates and were mainly located at the tip or middle area of the sperm heads. However, average incidence of normal sperm exhibiting large vacuoles was 4.6 and 4.2% in the patient and donor groups, respectively. (ii) Sperm chromosome assays did not reveal any differences in the incidence of structural chromosome aberrations between sperm exhibiting large vacuoles and those without them (9.1 versus 4.1%). (iii) No significant difference in frequency of TUNEL-positive cells was found between normal sperm with large vacuoles and those without them in the samples examined. Among 227 sperm exhibiting large vacuoles, only 7 cells were TUNEL positive. CONCLUSION The results showed that large vacuoles were not responsible for DNA damage, suggesting that intra-cytoplasmic injection of morphologically selected sperm may not be required for patients who produce high-quality semen.

Expression of natural cytotoxicity receptors on peritoneal fluid natural killer cell and cytokine production by peritoneal fluid natural killer cell in women with endometriosis.

To investigate the relationship between the expression of natural cytotoxicity receptors (NCRs) on peritoneal fluid (PF) natural killer (NK) (pfNK) cells and cytokine production by pfNK cells in women with endometriosis.

ORIGINAL ARTICLE: Correlation Between Natural Cytotoxicity Receptors and Intracellular Cytokine Expression of Peripheral Blood NK Cells in Women with Recurrent Pregnancy Losses and Implantation Failures

Problem  Natural cytotoxicity receptors (NCRs) are unique markers, which regulate NK cell cytotoxicity and cytokine production. We investigated whether women with recurrent pregnancy losses (RPLs) and implantation failures have aberrant correlation between NCRs and intracellular cytokine expression of NK cells.

Changes of NK Cells in Preeclampsia

The regulation of uterine and circulating peripheral blood natural killer (NK) cells has been associated with reproductive immunology such as recurrent pregnancy losses, implantation failures, or preeclampsia. Preeclampsia is a hypertensive disorder of pregnancy characterized by increased blood pressure accompanied by proteinuria and is a major cause of maternal and fetal mortality. Natural cytotoxicity receptors (NCRs) are unique markers, which regulate NK cell cytotoxicity and cytokine production. The relation of NCRs to reproduction is not fully characterized yet. The different profile of NCRs expression may suggest presence of abnormal regulation of NK cell in women with reproductive failures. Pregnant women with preeclampsia carry immunological abnormalities of NCRs on peripheral blood NK cells during pregnancy. The lower expression of NKp46+ NK cells in women with preeclampsia may account for the higher production of NK1 cytokine that is known as NK1 shift in pregnant women with preeclampsia. Evaluation of NKp46 on peripheral blood NK cells may be applicable to find the onset of preeclampsia. In this review, various expressions of NK cell surface markers including NCRs on NK cells, NK cell cytotoxicity, and production of cytokines and angiogenic factors by NK cells were reviewed in relation to preeclampsia.

Role of NKp46 Expression in Cytokine Production by CD56-Positive NK Cells in the Peripheral Blood and the Uterine Endometrium

To investigate the role of natural cytotoxicity receptor, NKp46 expression in cytokine‐producing NK cells.

Retinoic acid-inducible gene-I is induced by interferon-γ and regulates CXCL11 expression in HeLa cells

Retinoic acid-inducible gene-I (RIG-I) is a member of the DExH box family proteins, which have diverse roles in the regulation of gene expression and cellular functions. RIG-I is one of the factors regulated by interferon (IFN)-gamma and regarded as an intracellular signaling molecule for IFN-gamma. IFN-gamma is a major cytokine and also suggested to be involved in embryonal implantation and pregnancy. It is demonstrated that IFN-gamma stimulates endometrial epithelial cells to produce CXCL11, which is implicated in implantation. The aim of the present study was to investigate the effect of IFN-gamma on RIG-I expression in HeLa cells, a cell line derived from human uterine carcinoma. We found that RIG-I mRNA and protein were expressed in HeLa cells stimulated with IFN-gamma. The effect of IFN-gamma was observed in concentration- and time-dependent manners. The RNA interference against RIG-I resulted in the suppression of the IFN-gamma-induced CXCL11 expression. Immunohistochemical studies revealed the RIG-I expression in the normal human endometrium, suggesting a possible role of RIG-I in human reproductive organs.

NK22 Cells in the Uterine Mid-Secretory Endometrium and Peripheral Blood of Women with Recurrent Pregnancy Loss and Unexplained Infertility

We aimed to investigate natural killer 22 (NK22) cells in the peripheral blood and the uterine endometrium of women with unexplained recurrent pregnancy loss (URPL) and unexplained infertility (UI).

Erythrocytes counteract the negative effects of female ageing on mouse preimplantation embryo development and blastocyst formation

BACKGROUND The low developmental competence of embryos from ageing females remains an enigma; it is presumably attributable to oxidative stress. A number of antioxidant mechanisms exist in the erythrocyte and these have been investigated in other cells and tissues. However, very few studies have reported the effects of erythrocyte supplementation on developmental competence in ageing embryos. METHODS In Experiment 1, IVF embryos from young (7-10 weeks) mice were cultured in medium supplemented with an oxidizing agent, hypoxanthine/xanthine oxidase, in the presence and absence of erythrocytes. In Experiment 2, the development of embryos derived from young and ageing (40-50 weeks) female mice was assessed in the presence and absence of erythrocytes. RESULTS In Experiment 1, the presence of hypoxanthine/xanthine oxidase significantly inhibited embryo development (P < 0.0001). Erythrocyte supplementation clearly overcame the detrimental effects in a dose-related manner. In Experiment 2, in the absence of erythrocytes, developmental competence was significantly lower in embryos from ageing females than in those from young females (P < 0.01). However, in ageing females, the supplementation of erythrocytes significantly promoted the development of embryos to the blastocyst stage (51.1% versus 77.3%; P < 0.01). CONCLUSIONS Supplementation with erythrocytes can counteract the negative effect of maternal ageing on embryo development and blastocyst formation.

Differences in semen characteristics between patients with testicular cancer and other malignancies using various cut‐off values

To compare semen parameters between patients with testicular cancer and other malignancies using various cut‐off values, and to evaluate the correlation between semen parameters and intracytoplasmic sperm injection outcomes.