Human follicular fluids contain tissue macrophages

The role of macrophages in polycystic ovarian syndrome and its typical pathological features: A narrative review

Polycystic ovarian syndrome (PCOS) is the most common endocrine and metabolic disorder in women of childbearing age, with ovulatory dysfunction, hyperandrogenism, and polycystic ovarian morphology (PCOM) as the clinical features. Androgen excess, insulin resistance, obesity, adipose tissue dysfunction, ovulatory dysfunction, and gut microbiota dysbiosis are the main pathological features and pathogenesis of PCOS and are related to systemic chronic low-grade inflammation and chronic ovarian tissue inflammation in PCOS. With the advances in immune-endocrine interaction studies, research on the role of immune cells in the occurrence and development of PCOS is gradually increasing. As the core of innate immunity, macrophages play an indispensable role in systemic inflammatory response. Meanwhile, they are involved in maintaining the stability and function of the ovary as the most abundant immune cells in ovarian tissue. Studies in humans and mice have found that the polarization of macrophages into M1 type plays multiple roles in the pathogenesis of PCOS. This review describes the distribution characteristics of macrophage subpopulations in patients and animal models with PCOS, discusses the role of macrophage-related metabolic inflammation in PCOS, and summarizes the relationship between macrophages and PCOS-related pathological features and its possible mechanisms, to further understand the pathogenesis of PCOS and reveal the role of macrophages in it. In addition, research on immune-endocrine interactions can also provide direction for finding new therapeutic targets for PCOS.

SARS-CoV-2 infection negatively affects ovarian function in ART patients

Several organs, such as the heart, breasts, intestine, testes, and ovaries, have been reported to be target tissues of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. To date, no studies have demonstrated SARS-CoV-2 infection in the female reproductive system. In the present study, we investigated the effects of SARS-CoV-2 infection on ovarian function by comparing follicular fluid (FF) from control and recovered coronavirus disease 2019 (COVID-19) patients and by evaluating the influence of these FF on human endothelial and non-luteinized granulosa cell cultures. Our results showed that most FFs (91.3%) from screened post COVID-19 patients were positive for IgG antibodies against SARS-CoV-2. Additionally, patients with higher levels of IgG against SARS-CoV-2 had lower numbers of retrieved oocytes. While VEGF and IL-1β were significantly lower in post COVID-19 FF, IL-10 did not differ from that in control FF. Moreover, in COV434 cells stimulated with FF from post COVID-19 patients, steroidogenic acute regulatory protein (StAR), estrogen-receptor β (Erβ), and vascular endothelial growth factor (VEGF) expression were significantly decreased, whereas estrogen-receptor α (ERα) and 3β-hydroxysteroid dehydrogenase (3β-HSD) did not change. In endothelial cells stimulated with post COVID-19 FF, we observed a decrease in cell migration without changes in protein expression of certain angiogenic factors. Both cell types showed a significantly higher γH2AX expression when exposed to post COVID-19 FF. In conclusion, our results describe for the first time that the SARS-CoV-2 infection adversely affects the follicular microenvironment, thus dysregulating ovarian function.

Role of adipokines in the ovarian function: Oogenesis and steroidogenesis

Adipokines are mainly produced by adipose tissue; however, their expression has been reported in other organs including female reproductive tissues. Therefore, adipokines have opened new avenues of research in female fertility. In this regard, studies reported different roles for certain adipokines in ovarian function, although the role of other recently identified adipokines is still controversial. It seems that adipokines are essential for normal ovarian function and their abnormal levels could be associated with ovarian-related disorders. The objective of this study is to review the available information regarding the role of adipokines in ovarian functions including follicular development, oogenesis and steroidogenesis and also their involvement in ovary-related disorders.

Macrophages: an indispensable piece of ovarian health

Macrophages are the most abundant immune cells in the ovary. In addition to their roles in the innate immune system, these heterogeneous tissue-resident cells are responsive to tissue-derived signals, adapt to their local tissue environment, and specialize in unique functions to maintain tissue homeostasis. Research in the past decades has established a strong link between macrophages and various aspects of ovarian physiology, indicating a pivotal role of macrophages in ovarian health. However, unlike other intensively studied organs, the knowledge of ovarian macrophages dates back to the time when the heterogeneity of ontogeny, phenotype, and function of macrophages was not fully understood. In this review, we discuss the evolving understanding of the biology of ovarian tissue-resident macrophages, highlight their regulatory roles in normal ovarian functions, review the association between certain ovarian pathologies and disturbed macrophage homeostasis, and finally, discuss the technologies that are essential for addressing key questions in the field.

Protein Cargo of Extracellular Vesicles From Bovine Follicular Fluid and Analysis of Their Origin From Different Ovarian Cells

Follicular fluid (FF) fills the interior portion of the ovarian antral follicle and provides a suitable microenvironment for the growth of the enclosed oocyte through molecular factors that originate from plasma and the secretions of follicular cells. FF contains extracellular nanovesicles (ffEVs), including 30-100-nm membrane-coated exosomes, which carry different types of RNA, proteins, and lipids and directly influence oocyte competence to develop embryo. In the present study, we aimed to characterize the protein cargo of EVs from the FF of 3-6-mm follicles and uncover the origins of ffEVs by assessing expression levels of corresponding mRNAs in bovine follicular cells and oocyte and cell proteomes. Isolated exosome-like ffEVs were 53.6 + 23.3 nm in size and could be internalized by cumulus-oocyte complex. Proteomes of ffEVs and granulosa cells (GC) were assessed using nanoflow liquid chromatography coupled with high-resolution tandem mass spectrometry after the gel fractionation of total proteins. In total, 460 protein isoforms corresponding to 322 unique proteins were identified in ffEVs; among them, 190 were also identified via GC. Gene Ontology terms related to the ribosome, protein and RNA folding, molecular transport, endocytosis, signal transduction, complement and coagulation cascades, apoptosis, and developmental biology pathways, including PI3K-Akt signaling, were significantly enriched features of ffEV proteins. FfEVs contain numerous ribosome and RNA-binding proteins, which may serve to compact different RNAs to regulate gene expression and RNA degradation, and might transfer ribosomal constituents to the oocyte. Majority of genes encoding ffEV proteins expressed at different levels in follicular cells and oocyte, corroborating with numerous proteins, which were reported in bovine oocyte and cumulus cells in other studies thus indicating possible origin of ffEV proteins. The limited abundance of several mRNAs within follicular cells indicated that corresponding ffEV proteins likely originated from circulating exosomes released by other tissues. Analysis of bovine ffEV transcriptome revealed that mRNAs present in ffEV accounted for only 18.3% of detected ffEV proteins. In conclusion, our study revealed numerous proteins within ffEVs, which originated from follicular and other cells. These proteins are likely involved in the maintenance of follicular homeostasis and may affect oocyte competence.

A paracrine interaction between granulosa cells and leukocytes in the preovulatory follicle causes the increase in follicular G-CSF levels

Objective

Follicular granulocyte colony-stimulating factor (G-CSF) is a new biomarker of oocyte quality and embryo implantation in in vitro fertilization (IVF) cycles. Its role in reproduction is poorly understood. Our study aimed to investigate the mechanisms and cells responsible for G-CSF production in the preovulatory follicle.

Design

Laboratory research study.

Setting

Single-center study.

Interventions

Granulosa cells and leukocytes were isolated from the follicular fluids (FF) or the blood of women undergoing IVF and from the blood of a control group of women with spontaneous ovulatory cycles to perform cocultures.

Main outcome measure

G-CSF-secreted protein was quantified in the conditioned media of cocultures.

Results

G-CSF secretion was considerably increased in cocultures of granulosa cells and leukocytes. This effect was maximal when leukocytes were isolated from the blood of women in the late follicular phase of the menstrual cycle or from the FF of women undergoing IVF. The leukocyte population isolated from the FF samples of women undergoing IVF had a higher proportion of granulocytes than that isolated from the corresponding blood samples. Leukocytes induced the synthesis and secretion of G-CSF by granulosa cells. Among a range of other FF cytokines/chemokines, only growth-regulated oncogene alpha (GROα) was also increased.

Conclusion

The notable rise in G-CSF at the time of ovulation coincides with the accumulation of follicular granulocytes, which stimulate G-CSF production by granulosa cells via paracrine interactions. High follicular G-CSF concentrations may occur in follicles with optimal granulosa–leukocyte interactions, which could explain the increased implantation rate of embryos arising from these follicles.

Electronic supplementary material

The online version of this article (10.1007/s10815-020-01692-y) contains supplementary material, which is available to authorized users.

Messenger RNA and protein expression of tumor necrosis factor α and its receptors in human follicular granulosa cells

To evaluate the concentration of tumor necrosis factor α (TNF-α) and its soluble receptors (sTNFR I and II) in serum and follicular fluid (FF) at the time of oocyte retrieval and to detect expression of TNF-α and its receptors by luteinized granulosa cells (GCs). In a cross-sectional study and through an in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI) program, 81 women undergoing oocyte retrieval were recruited. Serum and FF were obtained from 81 women. GCs were pooled from 20 patients (from six different days of oocyte retrievals, 5-16 follicles per patient). TNF-α and its soluble receptors concentration were determined by enzyme-linked immunosorbent assay and also their expression by immune cytochemistry and reverse-transcription polymerase chain reaction analysis. The median TNF-α concentration in serum was 4.06 pg/ml (interquartile range [IQR], 3.71-6.14) and significantly higher than that in FF with 3.50 pg/ml (IQR, 3.05-5.01), p < 0.001. The sTNFR I and II levels in serum were lower and higher than FF, respectively. The TNF-α levels in serum and FF of good responders were higher than low responders (p = 0.017 and 0.021, respectively). TNF-α cut-off level for low responders versus good responders was 4.174 pg/ml in serum with a pregnancy rate of 25.8% and 40% for below and above of this level, respectively (p = 0.19). For FF, the cut-off value was 3.89 pg/ml. TNF-α and its receptors were expressed by GCs. The presence of TNF-α and its soluble receptors in serum and FF and their expression by GCs suggest an important role for this cytokine in ovarian function.

Cellular and molecular mechanisms of the preovulatory follicle differenciation and ovulation: What do we know in the mare relative to other species

Terminal follicular differentiation and ovulation are essential steps of reproduction. They are induced by the increase in circulating LH, and lead to the expulsion from the ovary of oocytes ready to be fertilized. This review summarizes our current understanding of cellular and molecular pathways that control ovulation using a broad mammalian literature, with a specific focus to the mare, which is unique in some aspects of ovarian function in some cases. Essential steps and key factors are approached. The first part of this review concerns LH, receptors and signaling, addressing the description of the equine gonadotropin and cloning, signaling pathways that are activated following the binding of LH to its receptors, and implication of transcription factors which better known are CCAAT-enhancer-binding proteins (CEBP) and cAMP response element-binding protein (CREB). The second and major part is devoted to the cellular and molecular actors within follicular cells during preovulatory maturation. We relate to 1) molecules involved in vascular permeability and vasoconstriction, 2) involvement of neuropeptides, such as kisspeptin, neurotrophins and neuronal growth factor, neuropeptide Y (NPY), 3) the modification of steroidogenesis, steroids intrafollicular levels and enzymes activity, 4) the local inflammation, with the increase in prostaglandins synthesis, and implication of leukotrienes, cytokines and glucocorticoids, 5) extracellular matrix remodelling with involvement of proteases, antiproteases and inhibitors, as well as relaxin, and finaly 6) the implication of oxytocine, osteopontin, growth factors and reactive oxygen species. The third part describes our current knowledge on molecular aspect of in vivo cumulus-oocyte-complexe maturation, with a specific focus on signaling pathways, paracrine factors, and intracellular regulations that occur in cumulus cells during expansion, and in the oocyte during nuclear and cytoplasmic meiosis resumption. Our aim was to give an overall and comprehensive map of the regulatory mechanisms that intervene within the preovulatory follicle during differentiation and ovulation.

Gonadotrophin stimulation in IVF alters the immune cell profile in follicular fluid and the cytokine concentrations in follicular fluid and serum

Study question

Are the immune cell profiles and the cytokine concentrations in follicular fluid (FF) and serum at the preovulatory stage different in conventional exogenous gonadotrophin stimulated IVF (c-IVF) compared with natural cycle IVF (NC-IVF)?

Summary answer

The cell counts of CD45+ leucocytes and T cell subpopulations and the cytokine concentrations in FF and serum are different in c-IVF compared to NC-IVF.

What is known already

FF-derived cells are heterogeneous. Immune cells are involved in intra-ovarian processes and cytokines are required for normal follicular development. Gonadotrophins stimulate the regulatory intrafollicular system and influence the local distribution of immune cells and the intrafollicular release of cytokines. Administration of exogenous gonadotrophins may have a significant effect on this local regulatory system, which then in turn could influence oocyte quality.

Study design, size, duration

The study included 105 patients, 69 undergoing c-IVF and 36 undergoing NC-IVF. c-IVF was performed by exogenous ovarian stimulation with hMG and GnRH antagonists.

Participants/materials, setting, methods

FF samples were collected from the first dominant follicle in c-IVF without pooling and from single leading preovulatory follicles in NC-IVF. Three different approaches were used to analyze FF samples: (i) microscopic investigation of CD45+ leucocytes, (ii) fluorescence-activated cell sorting to determine CD19+ B cells and CD3+ T cells including T cell subpopulations (CD4+, CD8+), and (iii) evaluation of tumour necrosis factor-alpha (TNF-α), interferon-gamma (INF-γ), interleukins (IL)-2, -6, -8, -10 and vascular endothelial growth factor (VEGF) levels in matched FF and serum samples using the Bio-Plex® platform.

Main results and the role of chance

FF obtained from c-IVF contained proportionally more CD45+ leucocytes (P = 0.0384), but fewer CD8+ cytotoxic T cells than FF from NC-IVF. CD3+ T lymphocytes were the most common type of lymphocytes, and the number thereof was comparable in the two study groups. In c-IVF, serum VEGF levels were higher (P = 0.007) than in NC-IVF while FF contained marginally decreased concentrations of IL-8 in c-IVF in comparison to NC-IVF. The cytokine concentration gradient between FF and serum in c-IVF was 10-fold for IL-8 and 8-fold for VEGF and thereby markedly lower than in NC-IVF, where the differences were 32-fold and 30-fold, respectively. Strong positive correlations were determined between FF- IL-10 and FF- VEGF in c-IVF (r = 0.85, P < 0.0001) and in NC-IVF (r = 0.81, P < 0.0001).

Large scale data

N/A.

Limitations, reasons for caution

The ovulation of NC-IVF follicles was induced by the exogenous administration of hCG, which means that the environment did not fully correspond to the physiological situation.

Wider implications of the findings

The differences in the immune profile and the cytokine concentrations in c-IVF and NC-IVF follicles support the hypothesis that conventional ovarian stimulation affects indirectly and heterogeneously the intrafollicular milieu, and thereby possibly affects the oocyte quality and the IVF outcome. However, further studies are needed to confirm our findings and to refine stimulation protocols in the context of optimizing the intrafollicular environment during oocyte maturation.

Study funding/competing interest(s)

The study was supported by a research grant from IBSA Institut Biochimique SA and MSD Merck Sharp & Dohme GmbH. The authors are clinically involved in low dose mono-follicular stimulation and IVF-therapies, using gonadotrophins from all gonadotrophins distributors on the Swiss market, including Institut Biochimique SA and MSD Merck Sharp & Dohme GmbH.

Expression of mesenchymal stem cells-related genes and plasticity of aspirated follicular cells obtained from infertile women

After removal of oocytes for in vitro fertilization, follicular aspirates which are rich in somatic follicular cells are discarded in daily medical practice. However, there is some evidence that less differentiated cells with stem cell characteristics are present among aspirated follicular cells (AFCs). The aim of this study was to culture AFCs in vitro and to analyze their gene expression profile. Using the RT² Profiler PCR array, we investigated the expression profile of 84 genes related to stemness, mesenchymal stem cells (MCSs), and cell differentiation in AFCs enriched by hypoosmotic protocol from follicular aspirates of infertile women involved in assisted reproduction programme in comparison with bone marrow-derived mesenchymal stem cells (BM-MSCs) and fibroblasts. Altogether the expression of 57 genes was detected in AFCs: 16 genes (OCT4, CD49f, CD106, CD146, CD45, CD54, IL10, IL1B, TNF, VEGF, VWF, HDAC1, MITF, RUNX2, PPARG, and PCAF) were upregulated and 20 genes (FGF2, CASP3, CD105, CD13, CD340, CD73, CD90, KDR, PDGFRB, BDNF, COL1A1, IL6, MMP2, NES, NUDT6, BMP6, SMURF2, BMP4, GDF5, and JAG1) were downregulated in AFCs when compared with BM-MSCs. The genes which were upregulated in AFCs were mostly related to MSCs and connected with ovarian function, and differed from those in fibroblasts. The cultured AFCs with predominating granulosa cells were successfully in vitro differentiated into adipogenic-, osteogenic-, and pancreatic-like cells. The upregulation of some MSC-specific genes and in vitro differentiation into other types of cells indicated a subpopulation of AFCs with specific stemness, which was not similar to those of BM-MSCs or fibroblasts.

CDC42-positive macrophages may prevent malignant transformation of ovarian endometriosis

It is currently thought that most clear cell and endometrioid carcinomas arise from ovarian endometriosis. We recently suggested that, besides their origin in the ovary, reduction of CDC42 messenger RNA (a member of the RHO GTPase family) may contribute to explain why clear cell carcinomas are not uncommonly found limited to the ovary (stage I). On the other hand, little is known about the expression of CDC42 in ovarian endometriosis with and without carcinoma. Twenty-two endometriotic cysts not associated with carcinoma, 19 endometriotic cysts associated with carcinoma (contiguous endometriosis), as well as the 19 corresponding tumors (11 clear cell, 4 endometrioid, and 4 mixed-clear cell and endometrioid-carcinomas) were investigated. We analyzed CDC42 expression both by real-time polymerase chain reaction and immunohistochemistry. Endometriotic cysts not associated with carcinoma showed higher expression of CDC42 messenger RNA than cysts associated with carcinoma (P = .002). Immunohistochemically, CDC42 was exclusively expressed by macrophages. CDC42-positive macrophages were present in most of the endometriotic cysts not associated with carcinoma (11/19, or 58%). In contrast, only 5 endometriotic cysts containing carcinoma (contiguous endometriosis) (5/18, or 28%) and 1 ovarian carcinoma arising from endometriosis (1/18, or 5%) had CDC42-positive macrophages (58% versus 28%, P = .065; 28% versus 5%, P = .046). Our results raise the possibility that CDC42-positive macrophages may prevent the development of endometrioid and clear cell carcinomas.

Microbial colonization of follicular fluid: alterations in cytokine expression and adverse assisted reproduction technology outcomes

BACKGROUND

Previous studies have measured cytokines expressed within follicular fluid and compared the profiles with the aetiology of infertility and/or successful or unsuccessful assisted reproduction technology (ART) outcomes.

METHODS

In this study, 71 paired follicular fluid and vaginal secretions collected from ART patients were cultured to detect microorganisms and tested for the presence of cytokines. Patient specimens were selected for assay based on two criteria: whether the follicular fluid specimen was colonized (with microorganisms prior to oocyte retrieval) or contaminated by vaginal flora and; the aetiology of infertility. Patients included fertile women (with infertile male partners; n = 18), women with endometriosis (n = 16) or polycystic ovary syndrome (PCOS, n = 14), or couples with a history of genital tract infection (n = 9) or idiopathic infertility (n = 14).

RESULTS

Microorganisms and cytokines were detected within all tested specimens. Colonizing microorganisms in follicular fluid were associated with: decreased fertilization rates for fertile women (P = 0.005), women with endometriosis (P = 0.0002) or PCOS (P = 0.002) compared with women whose follicular fluid was contaminated at the time of oocyte retrieval and with decreased pregnancy rates for couples with idiopathic infertility (P = 0.001). A single cytokine was discriminatory for women with an idiopathic aetiology of infertility (follicular fluid interleukin (IL)-18). Unique cytokine profiles were also associated with successful fertilization (IL-1α, IL-1β, IL-18 and vascular endothelial growth factor).

CONCLUSIONS

Follicular fluid is not sterile. Microorganisms colonizing follicular fluid and the ensuing cytokine response could be a further as yet unrecognized cause and/or predictor of adverse ART outcomes and infertility.

Peroxiredoxin 2 inhibits granulosa cell apoptosis during follicle atresia through the NFKB pathway in mice

Peroxiredoxin 2 (PRDX2) has been known to act as an antioxidant enzyme whose main function is H(2)O(2) reduction in cells. We aimed to study the expression patterns of PRDX2 in mouse ovaries and explore the function of this protein in apoptosis of granulosa cells (GCs). We found that the expression of the PRDX2 protein in atretic follicle GCs was markedly higher than in healthy follicle GCs. In vitro, the transfection of siRNA targeting the Prdx2 gene inhibited the proliferation and induced the apoptosis of primary cultured GCs. Furthermore, suppression of PRDX2 resulted in the augmentation of endogenous H(2)O(2), and the ability to eliminate the exogenous H(2)O(2) was attenuated. The expression of PRDX2 and nuclear factor kappa-light-chain-enhancer of activated B cells (NFKB), whose activity was inhibited by binding to IKB, increased in GCs treated with various concentrations of H(2)O(2) for 30 min. However, no significant change in cytoplasmic IKB expression was observed. At 2 h after treatment with H(2)O(2), nuclear NFKB expression level was reduced, cytoplasmic IKB expression was increased, and PRDX2 expression was unchanged. Silencing of the Prdx2 gene caused early changes in NFKB and IKB expression in the primary cultured GCs compared to that in control cells. Taken together, these data suggest that PRDX2 plays an important role in inhibiting apoptosis in GCs and that PRDX2 actions may be related to the expression of NFKB and IKB.

Cytokines and Growth Factors in Implantation

Implantation failure is the most important rate limiting factor in the success of assisted reproductive techniques like In vitro fertilization–embryo transfer (IVF-ET). Cytokines are multifunctional signaling molecules having an implicit role in the human implantation process. This review focuses on the redundant roles of cytokines during the various stages of implantation. It also indicates that levels of cytokines in biological fluids like serum and follicular fluid obtained during oocyte retrieval might act as determinants of implantation potential of the blastocyst. Thus a holistic, metabolomic approach of analyzing biological fluids may provide a simpler approach to study the hitherto enigmatic process rather than the proteomic and genomic approach.

Circulating level of macrophage colony-stimulating factor can be predictive for human in vitro fertilization outcome

OBJECTIVE

To evaluate the level of macrophage colony-stimulating factor (M-CSF) in serum in response to ovarian stimulation (group 1) in low-response (n = 26), moderate-response (n = 40), and high-response (n = 29) patients and to compare its changes (n = 23, group 2) throughout the menstrual cycle between pregnant and nonpregnant patients.

DESIGN

Randomized controlled trial.

SETTING

University IVF program.

PATIENT(S)

Ninety-five women undergoing IVF.

INTERVENTION(S)

Serum and FF collection from 95 women.

MAIN OUTCOME MEASURE(S)

The M-CSF concentration was determined by ELISA.

RESULT(S)

The M-CSF levels in FF were higher than in serum. The M-CSF levels in serum increased from low-, through moderate-, to high-response patients; pregnancy rates were 11.5%, 22.5%, and 51.7%, respectively. Levels of M-CSF in serum increased throughout stimulation until the day of oocyte retrieval and decreased until ET. During the postretrieval days, from the day of ET, through implantation, to the day of confirmation of pregnancy, the M-CSF levels of those patients who became pregnant (n = 13) increased significantly and reached their highest level. After implantation the M-CSF level decreased slightly and reached a plateau during gestation.

CONCLUSION(S)

Macrophage colony-stimulating factor is involved in follicle development and ovulation and could be an additional predictor for IVF outcome.

Regulation of granulosa and theca cell transcriptomes during ovarian antral follicle development

Coordinated interactions between ovarian granulosa and theca cells are required for female endocrine function and fertility. To elucidate these interactions the regulation of the granulosa and theca cell transcriptomes during bovine antral follicle development were investigated. Granulosa cells and theca cells were isolated from small (<5 mm), medium (5-10 mm), and large (>10 mm) antral bovine follicles. A microarray analysis of 24,000 bovine genes revealed that granulosa cells and theca cells each had gene sets specific to small, medium and large follicle cells. Transcripts regulated (i.e., minimally changed 1.5-fold) during antral follicle development for the granulosa cells involved 446 genes and for theca cells 248 genes. Only 28 regulated genes were common to both granulosa and theca cells. Regulated genes were functionally categorized with a focus on growth factors and cytokines expressed and regulated by the two cell types. Candidate regulatory growth factor proteins mediating both paracrine and autocrine cell-cell interactions include macrophage inflammatory protein (MIP1 beta), teratocarcinoma-derived growth factor 1 (TDGF1), stromal derived growth factor 1 (SDF1; i.e., CXCL12), growth differentiation factor 8 (GDF8), glia maturation factor gamma (GMFG), osteopontin (SPP1), angiopoietin 4 (ANGPT4), and chemokine ligands (CCL 2, 3, 5, and 8). The current study examined granulosa cell and theca cell regulated genes associated with bovine antral follicle development and identified candidate growth factors potentially involved in the regulation of cell-cell interactions required for ovarian function.

Role of cytokines in the regulation of reproductive function

The levels of 17 cytokines in the follicular fluid were measured by multiplex proteome analysis at the peak of stimulated ovulation during the in vitro fertilization cycle. In patients with ineffective folliculogenesis, the concentrations of IL-2, IL-4, IL-7, and granulocytic CSF in the follicular fluid were significantly lower than in women with greater mean number of collected oocytes. It was shown that multicomponent cytokine deficit was associated with lower production of high quality oocytes and lower efficiency of fertilization of the resultant oocytes in vitro. The absence of pregnancy after in vitro fertilization cycle is associated with lower levels of IL-2, IL-4, IL-7, granulocytic CSF, and macrophagic inflammatory protein 1b in combination with elevated contents of IL-8 and IL-13. The results attest to an important role of cytokines in the regulation of oogenesis and in preparation of the endometrium to implantation of the embryo.

Regulated upon activation, normal T cell expressed and secreted (RANTES) and monocyte chemotactic protein 1 in follicular fluid accumulate differentially in patients with and without endometriosis undergoing in vitro fertilization

OBJECTIVE

To compare the amount of regulated upon activation, normal T cell expressed and secreted (RANTES) and monocyte chemotactic protein 1 (MCP-1) in follicular fluid (FF) of patients with and without endometriosis and to determine their oocyte fertilization and pregnancy rates.

DESIGN

Case-control study.

SETTING

Department of Obstetrics and Gynecology, University Hospital Schleswig-Holstein, Campus Luebeck, Germany.

PATIENT(S)

Thirty-two women with endometriosis stages I-IV and 28 women without endometriosis, both groups surgically and histologically confirmed.

INTERVENTION(S)

Diagnostic laparoscopy, IVF-ET.

MAIN OUTCOME MEASURE(S)

RANTES and MCP-1 levels in follicular fluid, measured by ELISA, and oocyte fertilization and pregnancy rates.

RESULT(S)

Follicular response and days of gonadotropin stimulation were similar between the two groups. The levels of RANTES in FF from patients with endometriosis were significantly higher (460.4 +/- 90.3 pg/mL) compared with concentrations in patients with tubal infertility (243.8 +/- 70.9 pg/mL; P<.05). In contrast, MCP-1 concentrations in FF from women with endometriosis (330.0 +/- 29.2 pg/mL) were lower than in women with tubal infertility (420.5 +/- 46.6 pg/mL; P<.05). Oocyte fertilization rates in the endometriosis group (54%) were significantly lower than those of the tubal infertility group (73%; P<.05), as were the pregnancy rates (19% vs. 35%, respectively; P<.01).

CONCLUSION(S)

Women with endometriosis-associated infertility have a poor IVF outcome. Immune cell recruitment into the ovary might affect follicular function and lead to impaired oocyte quality.

Ovarian leukocyte distribution and cytokine/chemokine mRNA expression in follicular fluid cells in women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) affects 5-10% of reproductive-aged women and is commonly associated with anovulatory infertility. Leukocytes, together with granulosa cells, may contribute to the pathogenesis of PCOS via their ability to secrete an array of cytokines implicated in follicle growth. The aim of this study was to examine leukocyte subtypes in follicular phase ovaries and to quantify cytokine and chemokine mRNA expression in follicular fluid cells obtained at the time of oocyte retrieval before IVF in women with and without PCOS.

METHODS

Ovaries were immunostained for various leukocyte markers [CD3, CD4, CD14, CD15, CD45, CD45RA, CD45RO, CD57 and major histocompatibility complex (MHC) class II]. In addition, follicular fluid cells were subjected to quantitative RT-PCR to evaluate colony-stimulating factor-1 (CSF-1), granulocyte-macrophage (GM)-CSF, interleukins (IL-1beta, IL-6, IL-8 and IL-10), monocyte chemotactic protein (MCP-1) and tumour necrosis factor (TNFalpha) mRNA expression relative to beta-actin.

RESULTS

CD45RO+ cells (activated/memory T lymphocytes) were reduced by 60% in the theca layer of follicles from PCOS women. The relative abundance of macrophages and neutrophils was unchanged. Cytokine and chemokine mRNA transcripts examined were not affected by PCOS status. There was an association between high BMI and high TNFalpha and low IL-6 mRNA expression in follicular cells. IL-6 expression was higher in women who subsequently achieved pregnancy.

CONCLUSIONS

T lymphocytes potentially play a role in the local pathological mechanisms of PCOS. Further studies are required to identify their contribution to the aetiology of this common condition.

A simplified method for preparing IVF granulosa cells for culture

PURPOSE

To validate an expedited method for the removal of erythrocytes when preparing IVF granulosa-luteal cells for culture.

METHODS

Granulosa cells were enriched for culturing from follicular aspirates by density gradient centrifugation and by hypo-osmotic lysis treatments.

RESULTS

Cells prepared by either method showed the same cell viability and produced progesterone in similar quantities.

CONCLUSIONS

Using hypo-osmotic lysis to remove erythrocytes does not impair granulosa cell viability or steroidogenesis. It avoids multiple density gradient centrifugations and washings, and yields IVF granulosa cells ready for culture efficiently.

Expression and regulation of Sprouty-2 in the granulosa-lutein cells of the corpus luteum

Growth factor signalling has important modulatory roles in the process of human follicular growth, oocyte maturation and corpus luteum (CL) formation. Recently, Sprouty-2, an inhibitor of receptor tyrosine kinase (RTK) signalling pathway was advocated as a marker of oocyte competence in the bovine ovary. We sought to study Sprouty-2 expression and regulation in the human ovary. RT-PCR was used to detect Sprouty-2 mRNA in human granulosa-lutein cells (GLC) collected from follicular aspiration of IVF patients. The effect of epidermal and fibroblast growth factors (EGF and FGF) on Sprouty-2 mRNA expression in GLC was studied using quantitative real-time PCR. Immunohistochemistry was performed on cultured GLC, human CL and stimulated rat ovary sections. Sprouty-2 mRNA was expressed in human GLC. EGF and basic FGF, but not FGF4 and FGF10, increased Sprouty-2 mRNA expression in GLC. The Sprouty protein was localized to GLC of early and late human CL but not to the theca cell layer. Immunostaining of developing rat CL confirmed the temporal and spatial expression of Sprouty in humans. The detection of Sprouty-2 mRNA and protein in human GLC may suggest a role for Sprouty-2 during the final stages of follicle maturation and CL formation.

Leukocyte origin and profile in follicular aspirates at oocyte retrieval

BACKGROUND

Follicular aspirates represent a snapshot in time of conditions within the follicle at oocyte retrieval in women undergoing in vitro fertilization and embryo transfer. This clinical material has been much investigated and yet its cellular composition remains unclear. In this study we investigated the origin and profile of leukocytes found within follicular aspirates.

METHODS

We performed morphological and immunohistochemical analyses of follicular aspirates and peripheral blood obtained concurrently at oocyte retrieval.

RESULTS

There was no correlation between erythrocyte and leukocyte numbers in follicular aspirates. The profile of leukocyte subtypes within follicular aspirates was variable and differed significantly from the peripheral circulation in a significant proportion of the analysed samples. A subset of follicular aspirates displayed a marked increase in monocytes/macrophages and an apparent concomitant reduction in polymorphonuclear leukocytes compared with peripheral blood.

CONCLUSIONS

Leukocytes within follicular aspirates cannot be accounted for solely as a result of blood vessel damage during oocyte retrieval. The variation in leukocyte subtypes observed in some follicular aspirates may reflect a coordinated infiltration of these cells, characteristic of progressive inflammatory responses in other systems. The possibility that leukocyte variation is indicative of follicular maturation deserves further investigation due to its potential relevance in optimizing oocyte selection.

Reactive oxygen species in ovarian physiology

Cells living under aerobic conditions always face oxygen paradox. Oxygen is necessary for cells to maintain their lives. However, reactive oxygen species such as superoxide radical ( ), hydroxyl radical (OH^-) and hydrogen peroxide (H₂O₂) are generated from oxygen and damage cells. Oxidative stress occurs as a consequence of excessive production of reactive oxygen species and impaired antioxidant defense systems. Antioxidant enzymes include: superoxide dismutase (SOD), which is a specific enzyme to scavenge superoxide radicals; copper-zinc SOD, located in the cytosol; and manganese SOD, located in the mitochondria. Both types of SOD belong to the first enzymatic step to scavenge superoxide radicals. It has been reported that a number of local factors such as cytokines, growth factors and eicosanoids are involved in the regulation of ovarian function, in addition to gonadotropins and ovarian steroid hormones. Since reactive oxygen species are generated and SOD is expressed in the ovary, there is a possibility that reactive oxygen species and SOD work as local regulators of ovarian function. The present review reports that reactive oxygen species and their scavenging systems play important roles in several processes of reproductive physiology, including follicular development, oocyte maturation, ovulation, corpus luteum function and follicular atresia. (Reprod Med Biol 2005; 4: 31- 45).

The proportion of follicular fluid CD16+CD56DIM NK cells is increased in IVF patients with idiopathic infertility

One-fifth of all in-vitro fertilization (IVF) patients suffer from idiopathic infertility. A low fertilization rate is one of the most characteristic features of IVF in this group, probably caused by oocyte dysfunction. We speculate that an altered lymphocyte profile in follicular fluid (FF) may affect oocyte function and thus play a role in idiopathic infertility. Therefore, we compared levels of lymphocyte populations present in FF of 11 patients with idiopathic infertility (study group) with 29 patients in the control group, i.e. severe male factor infertility (n=17) or tubal factor infertility (n=12). Triple color flow cytometry was used to discriminate between T cells and NK cell subpopulations. In the idiopathic infertility group, a shift from T to NK cells was observed in FF as compared to the control group, caused mainly by a significant higher level of NK cells--20.3 and 13.6% (P<0.05), respectively. This high level of NK cells was due to a rise of the CD16+CD56dim NK cell subset. In peripheral blood, the NK cell levels showed a similar although not significant trend (P=0.08). As the CD16+CD56dim NK cell subpopulation is known for its cytotoxic properties, this subpopulation may negatively affect folliculogenesis and oocyte maturation, reflected by a diminished fertilization rate in the idiopathic infertility group. An altered lymphocyte profile in FF could therefore influence fertility in these patients.

Relationship between cytokine concentrations (FGF, sICAM-1 and SCF) in serum, follicular fluid and ICSI outcome

OBJECTIVE

The aim of this study was (i) to investigate the existence of fibroblast growth factor (FGF), soluble intracellular adhesion molecule-1 (sICAM-1), and stem cell factor (SCF) in serum and human follicular fluid (FF) of intracytoplasmic sperm injection (ICSI) patients, and (ii) to determine the relationship between these parameters and ICSI outcome.

MATERIAL AND METHOD

Seventy-five patients undergoing controlled ovarian hyperstimulation with human menopausal gonadotropin (hMG) after down-regulation with GnRHa were included in this study. The concentrations of FGF, SCF, and sICAM-1 were measured by using commercially available enzyme-linked immunosorbent assay test kits.

RESULTS

The FGF, sICAM-1, and SCF concentrations in the serum of women who become pregnant (group I) were 8.5 +/- 1.5 pg/mL, 235.8 +/- 81.1 ng/mL, and 597.7 +/- 139.9 pg/mL, and the corresponding concentrations of women who did not (group II) were 6.4 +/- 3.6 pg/mL, 230.6 +/- 66.5 ng/mL, and 569.6 +/- 91.4 pg/mL respectively. No significant difference was observed between the two investigated groups with regard to the number of hMG ampoules administered for controlled ovarian hyperstimulation, estradiol concentration on the day of human chorionic gonadotropin (hCG) injection, number of retrieved oocytes and fertilization rate.

CONCLUSION

The concentration of FGF, sICAM-1, and SCF did not differ significantly between the two groups in serum or in FF. Besides, the ICSI outcome was not related to their concentrations in serum or FF. Therefore, these parameters could not be used as a prognostic factor in ICSI program.

Morphodynamics of the follicular-luteal complex during early ovarian development and reproductive life

Female reproductive activity depends upon cyclic morphofunctional changes of the ovarian tissue during the female's fertile period, but the primum movens of an active gonadal rearrangement can be found from early phases of embryo development. To offer a basic account of the main steps of ovarian dynamics, we review the morphofunctional behavior of the follicular-luteal complex in an integrated study using light microscopy and transmission and scanning electron microscopy as well as through the use of numerous drawings. Particular emphasis is given to some reproductive aspects including (1) germ-somatic cell relationships and onset of folliculogenesis during early gonadal development; (2) follicular development and oocyte-follicle cell associations through adult folliculogenesis, finally leading to ovulation; (3) morphodynamics of corpus luteum formation, development, and regression, and (4) degenerative processes involving germ and somatic cells. The results reported, many of which originated in our laboratory, arise from some experiments on laboratory mammals but mostly from a large selection of human specimens. The data obtained are integrated and correlated with classic reports as well as with current views. Crucial biochemical, histophysiological, and clinical aspects are also emphasized.

Correlations between concentrations of interleukin-12 and interleukin-13 and lymphocyte subsets in the follicular fluid of women with and without polycystic ovary syndrome

OBJECTIVE

To investigate a possible correlation between interleukin-12 (IL-12) and IL-13 levels and lymphocyte subsets in the preovulatory follicles of patients with and without polycystic ovarian syndrome (PCOS).

DESIGN

Controlled clinical study.

SETTING

University hospital.

PATIENT(S)

Seventy-eight infertile women undergoing IVF-embryo transfer.

INTERVENTION(S)

The subjects underwent blood sampling, ovum retrieval, and embryo transfer.

MAIN OUTCOME MEASURES

Follicular fluid levels of T, androstenedione (A); IL-12, IL-13, activated T cells, T helper, and T-suppressor lymphocytes.

RESULT(S)

The level of IL-12 detected in follicular fluid (FF) was significantly lower in patients with PCOS than in normally ovulating women (mean: 1.47 +/- 0.3 pg/mL vs. 2.25 +/- 0.7 pg/mL, respectively); in contrast, FF IL-13 concentrations were significantly higher in the patients with PCOS than in the normally ovulating women (mean: 32.5 +/- 3.7 pg/mL vs. 19.6 +/- 2.5 pg/mL, respectively), as was the total number of activated T lymphocytes (11.5% +/- 1.5% vs. 4.8% +/- 0.4%). A significant correlation was observed between FF activated T-cell concentrations and FF IL-12, IL-13, T, and A levels. No significant differences were observed when these data were compared with embryological parameters.

CONCLUSION(S)

The present study shows significant differences in the correlation between FF IL-12 and IL-13 levels and T lymphocyte numbers in the subset of patients with PCOS as compared to normally ovulating women.

Macrophages in human reproductive tissues contain luteinizing hormone/chorionic gonadotropin receptors

PROBLEM

To determine whether macrophages in human reproductive tissues contain luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptor mRNA and receptor protein that can bind 125I-hCG.

METHOD OF STUDY

Macrophages isolated from term pregnancy human decidua were used for LH/hCG receptor detection by in situ hybridization for receptor mRNA and immunocytochemistry for a macrophage marker, CD68, performed alone and in combination, reverse transcription-nested polymerase chain reaction, Western and ligand blotting. The LH/hCG receptor presence in macrophages in late luteal phase human endometria and corpora lutea was determined by sequential performance of in situ hybridization and immunocytochemistry.

RESULTS

The macrophages present in term pregnancy human decidua and late luteal phase human endometria and corpora lutea contain LH/hCG receptors.

CONCLUSIONS

This is the first demonstration of macrophages present in human reproductive tissues containing LH/hCG receptors. The receptor presence suggests that LH and hCG may regulate macrophage functions in gonadal as well as in non-gonadal target tissues.

Follicular fluid concentration of leukaemia inhibitory factor is decreased among women with polycystic ovarian syndrome during assisted reproduction cycles

BACKGROUND

The possibility that a specific cytokine profile could be detected in the ovaries of patients with polycystic ovarian syndrome (PCOS) was investigated.

METHOD

Enzyme-linked immunosorbent assay (ELISA) or bioassays were used to assess the concentrations of leukaemia inhibitory factor (LIF), tumour necrosis factor, interleukin 11, gamma interferon, progesterone and oestradiol in follicular fluids from preovulatory follicles collected after ovarian stimulation from 15 PCOS patients, 15 infertile control patients with regular cycles, and 8 oocyte donors.

RESULTS

LIF and progesterone concentrations were significantly lower in the follicular fluid of PCOS patients (LIF median: 265 pg/ml) compared with controls (LIF median: 816 pg/ml); LIF and progesterone follicular fluid concentrations were correlated (r = 0.720, P = 0.0001). The LH/FSH ratio was negatively correlated with LIF concentrations (r = - 0.714, P = 0.0075). Although the PCOS and control patients did not differ significantly in age, ovarian reserve or IVF indication, the implantation rate was significantly lower among the women with PCOS (IR = 9 versus 21%, P = < 0.01).

CONCLUSION

The specific cytokine profile of the PCOS patients is probably related to the lower implantation rate since follicular fluid LIF appears to function as an embryotrophic agent.

Superoxide dismutase activity in human follicular fluid after controlled ovarian hyperstimulation in women undergoing in vitro fertilization

OBJECTIVE

To determine the activity of superoxide dismutase (SOD) and the total protein concentration in human preovulatory ovarian follicular fluid (FF) in relation to corresponding serum levels and the fertilization capacity of oocytes.

DESIGN

Prospective, observational study.

SETTING

Academic-based center for reproductive medicine.

PATIENT(S)

Twenty-eight female partners of infertile couples, 13 of whom were smokers, undergoing controlled ovarian hyperstimulation for IVF.

INTERVENTION(S)

Blood and follicular fluid samples were collected 34-36 hours after hCG administration.

MAIN OUTCOME MEASURE(S)

Levels of SOD activity and total protein concentrations.

RESULT(S)

Superoxide dismutase activity was present in all the FF studied and mean levels were statistically significantly higher than in serum. Total protein concentrations in serum were statistically significantly correlated with corresponding concentrations in FF. There was no difference in SOD activity between smokers and nonsmokers. Total protein concentrations in FF were marginally and statistically significantly lower in nonsmokers. Follicular fluid from patients whose oocytes did not become fertilized had a statistically significantly higher level of SOD activity than that from patients whose oocytes did become fertilized.

CONCLUSION(S)

Superoxide dismutase activity is present in FF and is higher than in serum. The degree of SOD activity is variable and seems to be inversely related to the fertilization of oocytes.

Interleukin-1beta and interleukin-1alpha may affect the implantation rate of patients undergoing in vitro fertilization-embryo transfer

OBJECTIVE

To investigate whether interleukin-1beta (IL-1beta) and interleukin-1alpha (IL-1alpha) affect the implantation rate of patients undergoing IVF-ET.

DESIGN

Follicular fluid and serum were obtained on the day of hCG administration, the day of oocyte retrieval, and the day of embryo transfer.

SETTING

Cellular immunology laboratory in a research institute, a high technology IVF unit in a medical center, and a university hospital.

PATIENT(S)

Thirty-three women who were undergoing IVF-ET.

MAIN OUTCOME MEASURE(S)

IL-1beta and IL-1alpha were measured by specific ELISA and their levels were correlated with the implantation rate.

RESULT(S)

Classification of IVF-ET patients according to their implantation rate revealed significantly higher amounts of follicular fluid IL-1beta in the implantation versus nonimplantation cycles (68.5+/-24.6 pg/mL versus 20.5+/-13.4 pg/mL); The difference between the level of IL-1alpha in the two groups was not statistically significant(11.6+/-5.1 pg/mL versus 7.3+/-1.9 pg/mL). In parallel, systemic FSH/hMG-dependent IL-1beta and IL-1alpha production was observed in implantation cycles but not in nonimplantation cycles. Statistically significant IL-1beta and IL-1alpha production was observed after administration of hCG.

CONCLUSION(S)

Gonadotropins used during IVF-ET induce local and systemic production of IL-1beta and IL-1alpha. In addition, the implantation rate for IVF-ET patients who have detectable serum concentrations of IL-1beta and IL-1beta on the day of hCG administration could be higher than the rate for IVF-ET patients who do not have detectable concentrations of these cytokines.

Gonadotropins induce the release of interleukin-1 beta, interleukin-6 and tumor necrosis factor-alpha from the human preovulatory follicle

PROBLEM

The effects of exogenous gonadotropin administration and steroid levels on the release of various cytokines into the human follicular fluid (FF) were studied.

METHOD OF STUDY

Forty patients were included in two groups, those undergoing controlled ovarian hyperstimulation (COH) (n = 33) and natural cycles (n = 7). FF transvaginal aspirations were performed 36 hr after administration of human chorionic gonadotropin or a spontaneous surge of luteinizing hormone, respectively. FF cytokine measurements were performed with sensitive immunoassays.

RESULTS

FF cytokine levels were higher after COH [interleukin (IL)-1 beta, 6.6 +/- 0.32 pg/ml; IL-6, 18.7 +/- 2.1 pg/ml; and tumor necrosis factor (TNF)-alpha, 32.5 +/- 4.9 pg/ml] than in natural unstimulated cycles (0.52 +/- 0.1 pg/ml, P < 0.001; 8.9 +/- 1.2 pg/ml, P < 0.01; and 13.2 +/- 2.6 pg/ml, P < 0.001, respectively). FF estradiol (E2) and progesterone levels were not statistically different between groups, despite the higher serum E2 levels observed in patients after COH.

CONCLUSIONS

Gonadotropins might regulate ovarian secretion of cytokines, because FF IL-1 beta, IL-6, and TNF-alpha levels after COH were higher than during natural cycles.

Early recognition of pregnancy by the maternal immune system

PROBLEM

Immunologic recognition of pregnancy is important for normal gestation. Successful pregnancy is characterized by a Th2 dominance, whereas there is a Th1 dominance in failed pregnancies. We assume that a signal given by the fertilized ovum induces a Th2 shift, necessary for a normal outcome. In vitro fertilization provides a tool for testing this possibility.

METHOD OF STUDY

Phytohemagglutinin-stimulated lymphocytes were incubated for 48 hr in the presence of culture media from in vitro fertilized eggs, as well as in follicular fluid (FF) and control supernatants. Total RNA was isolated from the lymphocytes by the guanidine-isothiocyanate method and interleukin (IL)-10 mRNA expression was detected by reverse transcription-polymerase chain reaction.

RESULTS

Ten percent of the activated lymphocytes incubated with FF expressed IL-10 mRNA, whereas 88% of the lymphocytes activated with supernatants of sperm + oocytes gave a positive signal. Significantly (P < 0.05) fewer (50%) lymphocytes stimulated in the presence of control supernatants also expressed mRNA for IL-10. In supernatants of activated lymphocytes incubated with the culture medium of spermia + oocytes, the concentration of IL-10 was significantly higher than in the lymphocytes incubated with FF.

CONCLUSION

These data suggest that the presence of the fertilized ovum induces a Th2 shift, which enables pregnancy to proceed to term.

The pathogenesis of ovarian hyperstimulation syndrome: a continuing enigma

PURPOSE

Our purpose was to review the available literature concerning the pathogenesis of ovarian hyperstimulation syndrome and, in light of the most recent information, to attempt to provide further insight on this iatrogenic complication associated with the induction of ovulation.

METHODS

Published studies related to this topic were identified through a computerized bibliographic search.

CONCLUSIONS

The exact mechanism for the development of ovarian hyperstimulation syndrome is still obscure. It is well established that the syndrome is associated with the process of ovulation induced by either luteinizing hormone or human chorionic gonadotropin. Following ovulation, one or more substances produced by the ovary are liberated in excess, increasing capillary permeability, resulting in the clinical features of the syndrome. It may well be that the syndrome is not triggered by a single mechanism but by the production and secretion of several substances acting in concert. These may include prostaglandins, cytokines, the ovarian reninangiotensin system, vascular endothelial growth factor, and nitric oxide.

Cytokines in the human ovary: presence in follicular fluid and correlation with leukotriene B4

PURPOSE

This study was undertaken to correlate the follicular levels of interleukin (IL)-1 alpha, IL-2, tumor necrosis factor-alpha (TNF-alpha), and leukotriene (LT) B4 with oocyte maturity, fertilization, and achievement of pregnancy.

METHODS

The material was obtained from 22 women undergoing IVF, 8 of whom became pregnant and 14 of whom did not.

RESULTS

All of the studied cytokines and LT B4 were found in follicular fluids, but there were no significant differences according to oocyte maturity, fertilization, embryo quality, and achievement of pregnancy. On the other hand, a significant positive correlation was found between IL-1 alpha and TNF-alpha, IL-1 alpha, and LT B4 as well as between TNF-alpha and LT B4 in follicular fluids with subsequently fertilized oocytes.

CONCLUSIONS

It seems that IL-1 alpha, TNF-alpha and LT B4 may take part in the process of follicle wall degradation, and their follicular correlations may suggest more optimal follicular and oocyte development and maturation.

Colony stimulating factor-1 in human follicular fluid

OBJECTIVE

To evaluate colony stimulating factor-1 (CSF-1) concentrations in serum and follicular fluid (FF) at the time of oocyte retrieval and to test for presence of messenger RNA (mRNA) for CSF-1 and its receptor, c-fms, in FF cells.

DESIGN

Collection of serum and FF at the time of oocyte retrieval.

SETTING

A university IVF program.

PATIENT(S)

Forty-five women undergoing oocyte retrieval for IVF.

INTERVENTION(S)

Serum and FF were obtained from 24 women, and FF only was obtained from 21 women.

MAIN OUTCOME MEASURE(S)

Colony-stimulating factor-1 concentrations were determined by RIA, and the presence of mRNA for CSF-1 and c-fms was determined by reverse transcriptase-polymerase chain reaction.

RESULT(S)

Mean FF concentrations of CSF-1 were significantly higher than mean serum levels (10.0 +/- 1.3 and 3.6 +/- 0.3 (+/-SE) ng/mL, respectively). Colony-stimulating factor-1 and c-fms message were detected in FF cells, and alternatively spliced forms of CSF-1 message were present.

CONCLUSION(S)

The presence of CSF-1, a primary regulator of tissue macrophages, in FF, and the presence of mRNA for CSF-1 and its receptor c-fms in FF-derived cells, suggest a role for this growth factor in ovarian function.

Growth-regulated alpha expression in human preovulatory follicles and ovarian cells

PROBLEM

Around the time of ovulation the number of neutrophils increases in the theca of the leading follicle. We hypothesized that growth-regulated alpha (GRO alpha), a neutrophil chemoat-tractant/activating factor, may be a modulator of periovulatory neutrophil chemotaxis.

METHOD

GRO alpha levels were measured in follicular fluids (n = 61). Granulosa-lutein and ovarian stromal cells were also cultured. After experimental paradigms, GRO alpha mRNA was evaluated by Northern analysis, GRO alpha in follicular fluids, and culture supernatants were quantified using ELISA.

RESULTS

In follicular fluids the mean pre-human chorionic gonadotropin (hCG) GRO alpha level was 51 +/- 24 (+/- SEM) pg/ml, post-hCG it was 210 +/- 20 pg/ml (P = 0.04). GRO was produced constitutively by ovarian stromal and granulosa-lutein cells. Interleukin-alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha) further stimulated GRO alpha production. Treatment of stromal cells with hCG also stimulated GRO alpha production.

CONCLUSION

GRO alpha is a constituent of periovulatory follicular fluid. Ovarian stromal and granulosa-lutein cells express the GRO alpha mRNA and produce the protein. The regulation of GRO alpha by cytokines and hCG suggests that GRO alpha may play a role in the process of ovulation.

Detection of immunoreactive interleukin-11 in human follicular fluid: correlations with ovarian steroid, insulin-like growth factor I levels, and follicular maturity

OBJECTIVE

To prove the presence of interleukin-11 (IL-11) in the follicular fluid (FF), to determine its source and the correlation between IL-11 and fertilization outcome, follicular size, number of follicles per patient, steroids, and insulin-like growth factor-1 (IGF-I) levels.

DESIGN

Interleukin-11 levels were measured in FFs, aspirated during oocyte pickup for IVF.

SETTING

Academic hospital and research environment.

PATIENT(S)

Follicular fluid and serum were obtained with informed consent from 44 patients undergoing IVF-ET. Granulosa cells were isolated from 17 patients.

MAIN OUTCOME MEASURE(S)

We hypothesized that IL-11 might play a role in follicular development, as do other related cytokines present in FF. Interleukin-11 was measured with ELISA.

RESULT(S)

Interleukin-11 was absent in the serum but present in FF and in conditioned medium from granulosa cells. Atretic follicles had higher concentrations of IL-11. No correlation was found between IL-11 and fertilization outcome, follicular size, steroid, IGF-I, and total protein concentrations.

CONCLUSION(S)

We conclude that IL-11 is present in FF. The role of IL-11 in follicular development should be the object of further investigations.

Tumor necrosis factor-alpha induces interleukin-6 mRNA and protein in human granulosa luteinizing cells via protein tyrosine kinase without involving ceramide

This study examines how interleukin-6 (IL-6) expression by human luteinizing granulosa cells is regulated. IL-6 was assayed in culture supernatants, mRNA in cells by in situ hybridization and by a competitive reverse-transcriptase polymerase chain reaction (RT-PCR). TNF alpha (100 pg-1 ng/ml) induced IL-6 mRNA and protein. Phorbol 12-myristate 13-acetate (PMA) (50 nM) mimicked this effect. DibutyrylcAMP (1 mM) and 10 microM forskolin. C2-, C6- and C8-ceramide (15 microM), all had no effect. The inhibitor of protein tyrosine kinase (PTK), genistein (100 micrograms/ml) reduced tumor necrosis factor (TNF) effects. The inhibitors of protein kinase C (PKC) (staurosporine, 10 nM), of phospholipase C (U73122, 2 microM), of phospholipase A2 (PLA2), (indomethacin 30 microM, mepacrin 50 microM, nordihydroguaiaretic acid 10 microM, ONO-RS-082 3,5 microM), none prevented it. Hence, IL-6 is induced by TNF alpha via activation of PTK. Protein kinase A, phosphoinositide and conventional PKC, sphingomyelin and PLA2 pathways are not implicated.

Monocyte chemotactic protein-1 expression in human preovulatory follicles and ovarian cells

There is a considerable population of macrophages (5-15% of the cells) within the human ovarian follicle at the time of ovulation. Macrophages are also present within the ovarian stroma, mostly near perifollicular capillaries. We hypothesized that macrophage migration in and around the preovulatory follicle is hormonally regulated and that regulation of macrophage migration occurs through local modulation of monocyte chemotactic protein-1 (MCP-1) that chemoattracts and activates monocytes/macrophages. In this regard, we investigated the expression and regulation of MCP-1 in human follicular fluid and in ovarian stromal and granulosa-lutein cell cultures. The concentration of MCP-1 in follicular fluid samples obtained from women prior to the administration of hCG was (n = 4) 90 +/- 27 (mean +/- S.E.) pg/ml; in samples obtained 12 h after the hCG administration it was (n = 3) 135 +/- 23 pg/mL; in follicular fluids obtained 34 h after the hCG administration it was (n = 126) 322 +/- 46 pg/mL (P = 0.007 vs. pre-hCG). The mean ratio of follicular fluid/serum MCP-1 levels was 4.18. There was a correlation between follicular fluid MCP-1 levels and follicular fluid or serum progesterone levels (r = 0.21, P = 0.02; r = 0.29, P = 0.03, respectively). MCP-1 mRNA and the protein were expressed in ovarian stromal and granulosalutein cells in culture and were increased by interleukin-1 alpha and tumor necrosis factor-alpha in a time- and concentration-dependent manner. LH/hCG induced higher levels of MCP-1 mRNA expression and protein production in both cell cultures. We propose that regulation of MCP-1 in ovarian stromal and granulosa-lutein cells by cytokines may play a role in the physiology of periovulatory events.

Review: cytokine involvement in ovarian processes

PROBLEM

Expression of tumor necrosis factor-alpha (TNF) and interleukins 1 alpha and 1 beta (IL-1) have been reported in ovaries of several species and humans and are implicated in ovarian follicular development and atresia, ovulation, steroidogenesis, and corpus luteum function (including formation, development, and regression). The principal abnormal processes affected by these cytokines are ovarian cancer and reduction of ovarian function during sepsis.

METHODS

A literature review.

RESULTS

Numerous studies indicate that TNF and IL-1 inhibit gonadotropin-stimulated steroidogenesis of undifferentiated ovarian cells due to inhibition of adenylyl cyclase and post-cAMP sites. In differentiated ovarian cells, these cytokines either stimulate progesterone synthesis or have little to no effect on steroidogenesis. Both cytokines participate in ovulation and levels of these cytokines increase during the preovulatory period. Endotoxin inhibits gonadotropin-stimulated ovarian steroidogenesis and follicular development and these effects are mediated, in part, by TNF and by direct effects of endotoxin on ovarian cells. IN newly formed corpora lutea, progesterone secretion is inhibited by TNF and IL-1, although each has proliferative effects. TNF also has been implicated in regression of corpora lutea because TNF stimulates prostaglandin synthesis and luteal TNF increases after initiation of the decline in progesterone secretion. TNF and IL-1 are secreted by some ovarian cancer cells and stimulate growth of these cells.

CONCLUSIONS

Thus, TNF and IL-1 are multifunctional factors affecting various ovarian processes.

Quantitative changes in macrophage distribution in normal mouse ovary over the course of the estrous cycle examined with an image analysis system

PROBLEM

The current study considered the distribution of macrophages within the major ovarian structures throughout the estrous cycle.

METHODS

Immunohistochemical analyses were carried out using an avidin-biotin-peroxidase staining method and the rat anti-mouse macrophage monoclonal antibody anti-Mac-l was applied to stain macrophages. A computer-assisted image analysis system was used to quantify and compare the distribution of macrophages within individual ovarian structures during the estrous cycle. The following morphological structures were analyzed: primordial, preantral, antral, pre-Graafian, and atretic follicles; first-, second-, and third-generation corpora lutea; and the interstitium. The analysis included follicular and corpus luteum substructures: theca, granulosa cells, and interstitium. The system allows the estimation of macrophage distribution as a macrophage density per microns2 of the defined area.

RESULTS

Primordial and preantral follicles did not contain macrophages during all stages of the estrous cycle. In antral, pre-graafian, and graafian follicles, macrophages were located and quantified only in the theca and were not detected in the granulosa cell layer. In contrast, atretic follicles showed macrophage localization in both thecal and granulosa cell layers. Macrophages were present in small numbers in the granulosa luteal cell layer and in high numbers in the thecal layer of newly developing corpora lutea. In the second generation of corpus luteum, macrophages followed the same pattern of distribution, while old corpora lutea contained significantly higher numbers of macrophages in both thecal and luteal cell layers. Surprisingly, significant quantitative changes in the macrophages distribution were detected over the course of the estrous cycle. Macrophage density was significantly higher in proestrus and metestrus when compared with the density in diestrus and estrus in most of the studied substructures with the exception of atretic follicles. Atretic follicles showed high macrophage density throughout the cycle with a two-fold higher density at metestrus.

CONCLUSION

Macrophages were present in the mouse ovary over the course of the estrous cycle. The greatest numbers of macrophages appearing in corpora lutea and in atretic follicles suggest a role for macrophages in corpus luteum differentiation and follicular atresia. Their patterns of distribution at proestrus and metestrus within microenvironmental compartments suggests a functional correlation with the events of ovarian development.

Flow cytometric evaluation of leukocyte subpopulations in the follicular fluids of infertile patients

OBJECTIVES

To evaluate the leukocyte subpopulations present in follicular fluid (FF) of infertile patients undergoing IVF-ET for tubal factor, idiopathic infertility, and endometriosis.

PATIENTS

Sixty patients undergoing IVF-ET with a tubal factor diagnosis (n = 35), idiopathic infertility (n = 13), and endometriosis (n = 12) had their subpopulations of FF leukocytes analyzed by flow cytometry.

MAIN OUTCOME MEASURE

Nonblood-contaminated samples of FF were collected under sterile conditions and centrifuged. Cells were labeled with a panel of monoclonal antibodies: anti-CD3, -CD4, -CD8, -CD14, -CD20, -CD45, and -CD56, and analyzed by cytofluorometry.

RESULTS

Follicular fluid leukocytes from patients with idiopathic infertility had a significantly higher proportion of T lymphocytes than tubal factor and endometriosis patients. Endometriosis patients had significantly higher proportions of natural killer (NK) cells, B lymphocytes, and monocytes compared with groups of idiopathic infertility and tubal factor.

CONCLUSIONS

The differences observed in the leukocyte subpopulations from FF of patients with idiopathic infertility and endometriosis may affect folliculogenesis and oocyte maturation. Moreover, these modifications could be one of the factors altering their fertility.