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S M Laird

Publications and source records attributed to S M Laird.

At least 19 recordsLinked to original sources
PubMed2006

Cytotrophoblast stem cell lines derived from human embryonic stem cells and their capacity to mimic invasive implantation events.

BACKGROUND: An effective embryonic-maternal interaction is crucial for successful human pregnancy. Failure of this process is a major cause of infertility and can lead to placental dysfunction resulting in recurrent miscarriage, fetal retardation and pre-eclampsia. Research is severely constrained by ethical and practical considerations; therefore, we aimed to generate cytotrophoblast stem (CTBS) cell lines from human embryonic stem cells (HESCs). METHOD: Beta-HCG was used as a marker of viable trophoblast cells. In defined culture, embryoid bodies were generated from HESCs and selected for trophoblast enrichment by rounds of cellular aggregation and disaggregation. Distinct CTBS cell lines were isolated and characterized. Spheroid cytotrophoblast bodies were generated and their interaction with luteal-phase endometrial stroma was analysed by real-time image analysis. RESULTS: Three CTBS cell lines were derived, which were maintained in the absence of residual HESCs, fibroblast feeder cells or extracellular matrix. CTBS cells displayed typical cytotrophoblast and syncytiotrophoblast characteristics and exhibited further differentiation to invasive endovascular cell phenotype. One cell line was generated with constitutive expression of enhanced green fluorescent protein (eGFP). Spheroid trophoblast bodies mimicked closely the early invasive stages of implantation when incubated with human endometrial stromal preparations in vitro. CONCLUSION: These human CTBS cell lines are a significant new model for investigating human placentation and may have considerable potential in cell therapy applications.

Cell Differentiation↗
PubMed2006

Cytokine expression in the endometrium of women with implantation failure and recurrent miscarriage.

One potential cause of reproductive failure such as infertility and recurrent miscarriage may be an endometrial defect. Numerous studies in mice have suggested the importance of various different cytokines in successful pregnancy outcome. This article reviews the literature available on the role of T helper cytokines and IL-1, IL-11, LIF, IL-12 and IL-18 in infertility and recurrent miscarriage, with particular emphasis on the role that endometrial cytokines may play. Although there are numerous studies on cytokines in recurrent miscarriage, much less has been reported on their role in infertility with or without failure after IVF. There is also considerable variation in the results obtained from various different studies, which may be due to different populations studied, the different timing of the sample collection, and whether the cytokines were measured in whole tissue or a specific cell population. The presence of complicated networks of cytokines and their overlapping biological activities means that alteration of one cytokine is likely to affect others and this also makes the study of their role in implantation failure very difficult. There is an urgent need to re-examine the role played by various cytokines in reproductive failure through carefully planned and vigorously designed studies and to compare the different types of reproductive failure.

Abortion, Habitual↗
PubMed2004

Expression of interleukin-11 receptor alpha and interleukin-11 protein in the endometrium of normal fertile women and women with recurrent miscarriage.

Interleukin-11 (IL-11) is a member of the IL-6 family of cytokines. Previous studies have suggested that IL-11 may play a role in human endometrial function. In this study, we have used immunocytochemistry to compare endometrial IL-11Ralpha and IL-11 expression in precisely timed peri-implantation biopsies from 9 normal fertile women and 16 recurrent miscarriage (RM) women. Immunocytochemistry was semi-quantified by obtaining an H-score value, which showed increased expression of both IL-11 and IL-11Ralpha in epithelial cells compared to stromal cells in all biopsies. There was a significant (P<0.01) reduction in epithelial cell IL-11, but not stromal cell IL-11, expression in endometrium from RM women compared to normal fertile women. There were no significant differences in expression of IL-11Ralpha protein in both stromal and epithelial cells in endometrium from the two groups of women. This work shows the presence of IL-11 and IL-11Ralpha within the endometrium of RM women during the peri-implantation period. The decreased expression of IL-11 in epithelial endometrium in RM women suggests that this cytokine may play a role in preventing miscarriage.

Abortion, Habitual↗
PubMed2004

Markers of endometrial function in women with unexplained recurrent pregnancy loss: a comparison between morphologically normal and retarded endometrium.

BACKGROUND: Endometrial defect, usually described as luteal phase defect (LPD), is associated with recurrent miscarriage. Recurrent miscarriage has also been associated with the abnormal expression of various molecules by endometrial cells. The aim of this study was to determine if any of these molecules or cells could be used to distinguish LPD from in-phase endometrium. METHODS: Immunocytochemistry was used to compare endometrial expression of CD45+, CD56+, CD3+ and CD4+ cells, leukaemia inhibitory factor, interleukin-6 and estrogen and progesterone receptors in precisely timed endometrial biopsies obtained between days LH+6 and LH+11 from recurrent miscarriage women with in-phase and retarded endometrium. RESULTS: In all samples there was a positive correlation between the number of CD45+ cells and LH day and a negative correlation between progesterone receptor and LIF expression and LH day. A significantly lower number (P<0.05) of CD56+ cells in peri-implantation endometrium and a decreased mid-cycle estrogen level (P<0.05) was seen in women with LPD compared to in-phase endometrium when single analysis was carried out. However, these differences were not significant after application of the Bonferroni correction for multiple analysis. CONCLUSIONS: The results are in line with previous associations observed between estrogen levels and LPD and suggest that the number of CD56+ cells is different in LPD and in-phase endometrium, although this could be due to delayed endometrial development in women with LPD. Interpretation must be cautious because these differences could have arisen by chance.

Abortion, Habitual↗
PubMed2003

Expression of leptin receptor isoforms in vitro: lack of effects of leptin on endometrial cytokine and MMP production.

PROBLEM: Leptin has a key role to play in human female reproduction. Its receptor is expressed highly throughout the reproductive tract. Cytokines have an important role in preparing the endometrium for implantation and leptin is known to modulate cytokine production in other tissues. We, therefore, investigated the possible role of leptin in endometrial growth and function. METHOD OF STUDY: Reverse transcriptase polymerase chain reaction and immunocytochemistry were used to determine the pattern of expression of leptin receptor isoforms in primary human endometrial epithelial and stromal cells in culture. The effect of leptin on cell growth and on the production of cytokines [Leukaemia Inhibitory Factor (LIF), interleukin 6 and tumour necrosis factor-alpha] and matrix metalloproteinases (MMP) (MMP2 and MMP-9) was also investigated. RESULTS: Expression of the long form of the leptin was restricted to the cultured endometrial, epithelial cells. Both cultured endometrial stromal and epithelial cells expressed the short and variant isoforms of the receptor. Incubation of epithelial and stromal cell cultures with varying concentrations of leptin (0-1000 ng/mL) had no significant effect on cell growth or levels of MMP-2 or MMP-9 production. Leptin also had no significant effect on cytokine production by epithelial cells. CONCLUSIONS: This study shows for the first time, the presence of leptin receptor isoforms on endometrial, epithelial and stromal cells in culture. Leptin had no effect on cytokine and MMP production by these cells. However, it is possible that leptin affects other factors within the endometrium not investigated here.

Adult↗
PubMed2002

Expression of nuclear factor kappa B components in human endometrium.

Nuclear factor kappa B (NFkappaB) is a family of transcription factors involved in signalling between IL1 and TNFalpha receptors and cytokines and adhesion molecules in a number of cell types, including those of the human endometrium. In this study, we used immunocytochemistry to investigate the in vivo expression of the p50, IkappaBalpha and IkappaBbeta NFkappaB components in endometrium obtained from normal fertile women throughout the menstrual cycle. All three components were expressed by both the stromal and epithelial cells of the endometrium and staining was predominately seen in the cytoplasm of the cells. Staining for p50 was more intense in the epithelial compartment than the stromal compartment. Staining in the stromal compartment was low to moderate throughout the cycle but, in the epithelial compartment, staining was cycle dependent and increased slightly during the mid-secretory phase. The staining patterns for IkappaBalpha and IkappaBbeta were similar. As for p50, staining for both proteins was greater in the epithelial compartment compared to the stromal compartment and stromal cell staining was low to moderate throughout the cycle. However, in contrast to p50, staining for the IkappaB proteins in epithelial cells decreased during the mid-secretory phase of the cycle. Although the immunocytochemistry technique used is only semi-quantitative, the results suggest an increased expression of the active and a decreased expression of the inhibitory NFkappaB components by the endometrium at the time of implantation. If confirmed, it would suggest that NFkappaB is involved in the control of factors important in the implantation process.

Adult↗
PubMed2002

IL-1, IL-6 and TNF-alpha concentrations in the peritoneal fluid of women with pelvic adhesions.

BACKGROUND: Pelvic adhesions are a significant cause of morbidity and are associated with infertility and pain. The three pro-inflammatory cytokines interleukin (IL)-1, IL-6 and tumour necrosis factor (TNF)-alpha are involved in adhesion formation/reformation. METHODS: The concentration of these three cytokines was examined in the peritoneal fluid of women undergoing laparoscopy, in order to examine the factors affecting their concentrations, with specific reference to the presence or absence of adhesions. RESULTS: We found that the concentration of TNF-alpha in the peritoneal fluid was significantly correlated to the menstrual cycle day (P < 0.01), with increasing concentration as the menstrual cycle progressed from the follicular to the luteal phase. In contrast, IL-1 and IL-6 levels did not show any variation throughout the menstrual cycle. Increased TNF-alpha was found in patients with pelvic adhesions compared with those with normal pelvis; the concentration of TNF-alpha was highest in mild compared with severe adhesions. In contrast, IL-1 concentration was higher in the presence of severe adhesions. IL-6 levels were significantly correlated with the grade of endometriosis (P < 0.05), but there were no significant correlations of either TNF-alpha or IL-1 concentrations with the various grades of endometriosis. CONCLUSION: The exact role of TNF-alpha and IL-1 in adhesion formation is still unknown, but the results from this study suggest that their concentration in the peritoneal fluid is associated with the degree of adhesions present.

Adnexal Diseases↗
PubMed2002

The correlation of adhesions and peritoneal fluid cytokine concentrations: a pilot study.

BACKGROUND: Intra-abdominal adhesion formation and reformation after surgery is a significant cause of morbidity. The greatest problem after the surgical removal of adhesions is their reformation. We examined the concentrations of interleukin (IL)-1, IL-6 and tumour necrosis factor (TNF)-alpha in the peritoneal fluid throughout the 48 h post-operative period following adhesiolysis, and correlated the results to the extent of adhesion reformation. METHODS: Peritoneal fluid, collected from eight patients following laparoscopy and again at 12, 36 and 48 h after surgery, was analysed using enzyme-linked immunosorbent assay (IL-1 and IL-6) and bioassay (TNF-alpha). At 48 h, a second look laparoscopy was performed to inspect the pelvis for adhesion formation/reformation. RESULTS: Three patients had adhesion reformation >10% at 48 h after surgery. The mean adhesion score 48 h after adhesiolysis was 5 (range 0-17). The mean reduction in adhesion score was 88% (range 83-100%). Newly formed adhesions were filmy, relatively soft and avascular in nature. Adhesion reformation of >10% was associated with (i) high concentrations of IL-6 at 12 h (P < 0.01) and (ii) high concentrations of IL-1 at 48 h (P < 0.001). CONCLUSIONS: Results from this preliminary study suggest that future treatment strategies for adhesion prevention could be aimed at the control of cellular mediators in the peritoneal fluid during the initial adhesion formation period.

Adult↗
PubMed2002

Expression of interleukin (IL)-11 receptor by the human endometrium in vivo and effects of IL-11, IL-6 and LIF on the production of MMP and cytokines by human endometrial cells in vitro.

Interleukin (IL)-6, leukaemia inhibitory factor (LIF) and IL-11 belong to the same family of cytokines whose receptors utilize gp130 as the signalling molecule. We have investigated the expression of the IL-11 receptor, IL-11Ralpha, protein in the human endometrium in vivo and the effects of IL-6, LIF and IL-11 on the production of metalloproteinases (MMPs) and cytokines by cultured endometrial epithelial and stromal cells. Immunostaining showed that IL-11Ralpha was expressed in both epithelial and stromal cells, with epithelial staining being more intense than stromal staining and little variation in staining in either compartment throughout the cycle. Incubation of both stromal and epithelial cells with IL-6, LIF and IL-11 had no effect on MMP-2, -7, -9, transforming growth factor (TGF)beta or IL-1beta production or cell growth. IL-6 and LIF also had no effect on tumour necrosis factor (TNF)alpha production, but IL-11 caused a dose-dependent decrease in TNFalpha production by epithelial cells. IL-6 receptor, LIF receptor and gp130 were all expressed by cultured stromal and epithelial cells, showing that the lack of effect is not due to lack of expression of the receptor components. The results show that although IL-6, LIF and IL-11 signal through the same molecule, they may have different effects in endometrial cells, suggesting the activation of different signalling pathways, which may ultimately be important in the control of endometrial function.

Adult↗
PubMed2001

Interleukin-11 (IL-11) in human endometrium: expression throughout the menstrual cycle and the effects of cytokines on endometrial IL-11 production in vitro.

Interleukin-11 is a member of the IL-6 family of cytokines. Its presence in mouse decidua has been shown and experiments in genetically modified mice have suggested the importance of its receptor in stromal cell decidualization. In this study we used immunocytochemistry to determine expression of IL-11 in human endometrium. The effects of TNFalpha, IL-1alpha and TGFbeta on IL-11 production by epithelial and stromal cells was also investigated. Immunocytochemical staining in sections cut from 19 endometrial biopsies obtained throughout the menstrual cycle showed that IL-11 was expressed in both human endometrial epithelial and stromal cells, with epithelial staining being more intense than that seen in the stromal cells, at all times except the late secretory phase when the intensity was similar. Basal IL-11 production by cultured epithelial cells was greater than basal production by stromal cells. IL-1alpha, TNFalpha and TGFbeta (0.1-10 ng/ml) all caused a concentration-dependent increase in IL-11 production by both epithelial and stromal cells, but stimulated: basal values were greater for stromal than epithelial cells for all three cytokines. This work shows, for the first time, the presence of IL-11 within the human endometrium and that its production is controlled by other cytokines, which are postulated to play a role in implantation. Thus IL-11 may also play an important role in human endometrial function and embryo implantation.

Adult↗
PubMed2001

Obstetric and neonatal outcome in women with a history of recurrent miscarriage: a cohort study.

Obstetric and neonatal outcomes of women who had a history of recurrent miscarriage were compared with a control population from 1 January 1992 to 30 June 1998. Amongst a total of 162 pregnancies which progressed beyond 24 weeks gestation in women with a history of recurrent miscarriage, there were four perinatal deaths and 16 babies were admitted to the special care baby unit. The rates of preterm delivery (13%), small-for-gestational-age (13%), perinatal loss (2.5%) and Caesarean section (36%) were significantly (P < 0.05) higher than those of the control group (3.9, 2.1, 1 and 16.7% respectively). The ratio of male to female babies was equal. There was no significant difference in the incidence of hypertension or diabetes between the two groups. Patients with recurrent miscarriage represent a population at high risk of obstetric problems and close surveillance in the antenatal period is therefore required.

Abortion, Habitual↗
PubMed2001

A prospective randomized controlled study comparing two doses of gestodene in cyclic combined HRT preparations on endometrial physiology.

Postmenopausal women taking oestradiol 17-beta 2 mg daily were randomized to receive either 25 or 50 microg gestodene from day 17 to 28 of the cycle in a double-blind study. Placental protein P14 (PP14) and CA 125 concentrations in uterine flushing, endometrial morphology and irregular bleeding after 12 cycles of study were observed. Eleven and 12 women in the 25 and 50 microg groups respectively completed the study. There were no significant differences in pre-treatment biochemical and morphological indices between the groups. The median PP14 concentration increased from 332 to 5800 ng/ml (P < 0.001) and from 145 to 27 160 ng/ml (P < 0.001) in the 25 and 50 microg gestodene groups respectively. No between-group significant rise of PP14 was observed. Similarly, no significant change was seen between the initial and post-treatment concentrations of CA 125 for either group. All biopsies were atrophic at inception of the study, and both regimens produced secretory endometrial transformation in the majority of biopsies. No between-group difference was observed in the morphometric indices measured, or any significant correlation between the concentrations of PP14 or CA 125 and morphology. The mean number of days of withdrawal bleeding (3.8 and 4.2 days for 25 and 50 microg respectively) were similar. In conclusion, both regimens produced a significant rise in uterine flushing concentrations of PP14, but not CA 125. PP14 is a sensitive biochemical marker in the assessment of endometrial response to hormone replacement therapy.

Adult↗
PubMed2001

Leptin and leptin-binding activity in women with recurrent miscarriage: correlation with pregnancy outcome.

BACKGROUND: Previous studies in humans and mice have suggested the importance of leptin in fetal growth. Recurrent miscarriage may be a result of abnormal placental and/or fetal development and therefore abnormal leptin levels may be associated with this form of pregnancy loss. METHODS: Leptin and leptin-binding activity (LBA) were measured in blood obtained from women who had a history of recurrent miscarriage (n = 53) during weeks 5-6 and 7-8 of pregnancy, and the concentrations were correlated with subsequent pregnancy outcome. RESULTS: Concentrations of leptin ranged from 1.4-62.8 ng/ml, but there was a strong correlation (r = 0.825, P < 0.001) between leptin values at weeks 5-6 and 7-8 in the same woman. Women who subsequently miscarried had significantly lower plasma leptin concentrations on both weeks 5-6 (13.34 +/- 2.1 ng/ml) (P < 0.05) and 7-8 (13.71 +/- 2.4 ng/ml) (P < 0.01) of pregnancy, than women who subsequently had a term birth (22.04 +/- 2.43 ng/ml week 5-6, 24.76 +/- 3.66 ng/ml week 7-8). LBA values ranged from 1-8.5% but there was no significant difference in LBA in blood obtained from women who subsequently miscarried or had a live birth. CONCLUSIONS: The significantly lower concentrations of leptin in women who subsequently miscarried suggest that leptin may play a role in preventing miscarriage. However, as there was a considerable overlap between the values of leptin in women who subsequently miscarried, and those that had a live birth, these measurements are of limited use in the prediction of pregnancy outcome in these women.

Abortion, Habitual↗
PubMed2000

Do androgens have a direct effect on endometrial function? An in vitro study.

OBJECTIVE: To test the hypothesis that androgens have a direct effect on the function of endometrial epithelial cells. DESIGN: In vitro study. SETTING: Academic research center. PATIENT(S): Endometrial epithelial cells were prepared from biopsy samples obtained from normal fertile women. INTERVENTIONS: Cells were incubated with androstenedione, testosterone, dihydrotestosterone, and DHEA. MAIN OUTCOME MEASURE(S): Secretion of glycodelin A into the culture fluid was used to assess secretory activity. Uptake of (3)H-thymidine and immunostaining for Ki67 was used to assess cell growth. The specific action of the androgens was confirmed by incubation with an antiandrogen, cyproterone acetate. RESULT(S): Androstenedione (10(-6) M and 10(-7) M) caused a dose-dependent decrease in glycodelin A secretion, uptake of (3)H-thymidine, and percentage of positive Ki67 cells in cultured human endometrial epithelial cells. Testosterone, dihydrotestosterone, and DHEA had no effect on glycodelin A secretion or (3)H-thymidine uptake. The direct effect of androgens on endometrial function were confirmed by demonstrating the presence of androgen receptors in cultured endometrial epithelial cells and showing that the direct effects of the androgens were not observed when cyproterone acetate was added to the cultures. CONCLUSION(S): The results suggest that androstenedione can inhibit human endometrial cell growth and secretory activity. Infertility and miscarriage associated with high androgen levels (e.g., that caused by the polycystic ovary syndrome) may be due to an adverse effect of high androgen levels on the endometrium.

Androgens↗
PubMed2000

Expression of nuclear factor kappa B in human endometrium; role in the control of interleukin 6 and leukaemia inhibitory factor production.

Expression of the rel-A component of nuclear factor kappa B (NFkappaB) by human endometrial cells was investigated by immunocytochemical analysis of cryostat sections cut from endometrial biopsy material and of cultured endometrial epithelial cells. In-vivo expression of rel-A was low in epithelial cells in endometrium obtained during the proliferative phase of the cycle, but increased in these cells during the secretory phase and was maximal at the time of implantation. In-vivo expression of rel-A by stromal cells did not vary greatly throughout the cycle, but showed a slight peak at the time of ovulation. In contrast similar expression of rel-A was seen in short-term cultures of epithelial cells prepared from both proliferative and secretory endometrium. Addition of the NFkappaB inhibitor SN50 (5 microg/ml) to confluent cultures of endometrial epithelial cells inhibited interleukin (IL)-1alpha (10 ng/ml) and tumour necrosis factor alpha (TNFalpha) (10 ng/ml) stimulated IL-6 (P < 0.001 and P < 0.01 respectively) and LIF (P < 0.01 and P < 0.05 respectively) production. The proteasome inhibitor MG132 (0.3 and 3 micromol/l) also caused a dose-dependent decrease in IL-1alpha and TNFalpha-stimulated IL-6 (P < 0.001 and P < 0.001 respectively) and leukaemia inhibitory factor (LIF) (P < 0. 001 and P < 0.001 respectively) production by endometrial epithelial cells. The results support the hypothesis that NFkappaB mediates signalling between IL-1 and TNFalpha receptors and the expression of LIF and IL-6 in endometrial epithelial cells.

Adult↗
PubMed1999

Metalloproteinases and tissue inhibitor of metalloproteinase 1 (TIMP-1) in endometrial flushings from pre- and post-menopausal women and from women with endometrial adenocarcinoma.

The presence of metalloproteinase activity in endometrial flushings obtained from premenopausal women, during the proliferative and secretory phases of the menstrual cycle, control post-menopausal women and women with post-menopausal bleeding (PMB) with or without adenocarcinoma was analysed by zymography. In addition, quantitative measurements of matrix metalloproteinase 2 (MMP-2), MMP-3, MMP-9 and tissue inhibitor of metalloproteinase 1 (TIMP-1) in the flushings were obtained by ELISA. The zymography results showed eight bands of activity, with molecular weights ranging from 51 to 208 kDa in the flushings from pre-menopausal women and post-menopausal women, particularly those with adenocarcinoma. Both zymography and ELISA showed that MMP-2 and MMP-9 were the major metalloproteinases found in the flushings and only low concentrations of MMP-3 were found. Concentrations of MMP-2 in pre-menopausal women were higher in flushings obtained during the secretory phase of the menstrual cycle than those obtained in the proliferative phase (P < 0.05), suggesting that it may play a role in embryo implantation. Concentrations of MMP-2 (P < 0.001), MMP-9 (P < 0.05) and TIMP-1 (P < 0.001) in the flushings from post-menopausal control women were lower than those from pre-menopausal women. Concentrations of MMP-2 (P < 0.05) and TIMP-1 (P < 0.05) were higher in flushings from women with PMB without carcinoma compared with post-menopausal controls and concentrations of MMP-9 (P < 0.01) and TIMP-1 (P < 0.05) in flushings from women with adenocarcinoma were higher than in post-menopausal controls. Among subjects with PMB, concentrations of MMP-9 in women with adenocarcinoma were higher than those without carcinoma (P < 0.05). Our results show that concentrations of MMP-2, MMP-9 and TIMP-1, but not MMP-3, are associated with endometrial activity and, therefore, may have a role in the breakdown of endometrial tissue. In addition, the increased concentrations of MMP-9 in flushings of women with adenocarcinoma indicate that this particular proteinase is associated with the presence of endometrial neoplastic cells.

Adenocarcinoma↗
PubMed1999

Serum leptin levels during the menstrual cycle of healthy fertile women.

Leptin is a protein, produced by adipose tissue, which has cytokine and hormonal properties. Serum leptin levels can be considered as a measure of body fat mass, and are involved in regulation of body weight. Previous studies suggest that leptin may have an additional role in reproduction, and there is also evidence for involvement in the hypothalamic-pituitary-gonadal axis. In this study, we investigate the possible changes in serum leptin concentration throughout the menstrual cycle. Samples were collected from apparently healthy, fertile women at different stages in their menstrual cycle, timed precisely according to the luteinising hormone (LH) surge. Mean serum leptin levels were significantly higher in the luteal phase (median 11.4 ng/mL) than in the follicular phase (median 10.0 ng/mL) (P < 0.001). In addition, mean serum leptin levels correlated with body mass index (r = 0.54, P < 0.05), but showed no correlation with luteal-phase progesterone levels. Results showed that levels of serum leptin vary during the menstrual cycle, and add to the mounting evidence that leptin has a role in reproduction. These fluctuations should be taken into account whenever studies are performed using female subjects.

Adult↗