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M L Polan

Publications and source records attributed to M L Polan.

At least 37 records · Page 2Linked to original sources
PubMed1998

Single blastomeres within human preimplantation embryos express different amounts of messenger ribonucleic acid for beta-actin and interleukin-1 receptor type I.

Gaining knowledge about the physiological timetable of gene expression during preimplantation embryo development is crucial, and a better understanding of cytokine and growth factor expression in early embryonic development could lead to improved in vitro culture conditions and enhance in vitro fertilization implantation rates. Our aim was to detect the patterns and levels of two messenger ribonucleic acids [mRNAs; beta-actin and interleukin-1 receptor type I (IL-1R tI)] in single human blastomeres by RT-nested PCR and to compare possible variations in the gene expression both between different embryos and in multiple blastomeres within the same embryo. Single blastomeres from nine human tripronucleic preimplantation embryos were examined by one round of RT and two rounds of nested competitive PCR. Beta-actin mRNA was detected in each blastomere, and IL-1R tI mRNA was found in 72% of the blastomeres examined. Beta-actin was expressed at a level of 511-12185 molecules of complementary DNA/blastomere, and IL-1R tI was expressed at a level of 2-290 molecules of complementary DNA/blastomere. Our results suggest that the mRNA pattern of an embryo cannot be reliably quantitated from the mRNA pattern of a single blastomere and therefore imply limitations for the use of this method for preimplantation diagnosis.

Actins↗
PubMed1998

Cytokine-mediated regulation of 92-kilodalton type IV collagenase, tissue inhibitor or metalloproteinase-1 (TIMP-1), and TIMP-3 messenger ribonucleic acid expression in human endometrial stromal cells.

Interleukin-1 (IL-1) is expressed in human endometrium and has been shown to play an integral role in local cellular interactions during implantation. In addition, the matrix metalloproteinase (MMP) and its inhibitor, the tissue inhibitor of metalloproteinase (TIMP), are crucial during implantation, mediating in vitro trophoblast penetration, and are regulated by several cytokines expressed by trophoblast cells. We have investigated the roles of IL-1 beta and transforming growth factor-beta (TGF beta) in regulating TIMP-1, TIMP-3, and 92-kDa type IV collagenase messenger ribonucleic acid (mRNA) expression in human endometrial stromal cells using quantitative competitive PCR. Confluent stromal cell cultures treated with progesterone and estradiol for 9 days were stimulated with IL-1 beta, IL-1 beta plus anti-IL-1 beta antibody, TGF beta, and TGF beta plus anti-TGF beta antibody for an additional 24 h. Competitive complementary DNA fragments were constructed by deletion of a defined fragment from each of the target complementary DNA sequences and coamplified in quantitative competitive PCR as an internal standard. TIMP-1 and TIMP-3, but not 92-kDa type IV collagenase mRNA, were expressed in stromal cells. The 92-kDa type IV collagenase mRNA was only expressed after stimulation with IL-1 beta. IL-1 beta both augmented 92-kDa type IV collagenase mRNA expression and decreased TIMP-1 and TIMP-3 mRNA expression in a dose-dependent manner. Conversely, TGF beta augmented TIMP-1 and TIMP-3 mRNA expression, but did not affect 92-kDa type IV collagenase expression. IL-1 and TGF beta-mediated changes were both neutralized by specific antibodies. These results provide indirect evidence that IL-1 and TGF beta may play crucial roles at the embryo-maternal interface during trophoblast invasion by regulating stromal cell expression of TIMP-1, TIMP-3, and 92-kDa type IV collagenase, all of which are known to be important in trophoblast invasion.

Cells, Cultured↗
PubMed1997

Different pattern of interleukin-1 beta-(IL-1 beta), interleukin-1 receptor antagonist- (IL-1ra) and interleukin-1 receptor type I- (IL-1R tI) mRNA-expression in single preimplantation mouse embryos at various developmental stages.

The interleukin-1 (IL-1) system has been shown to play an important role in human and murine embryo implantation. Recent studies have documented immunohistochemical evidence of interleukin-1 beta (IL--1 beta), interleukin-1 receptor antagonist (IL-1ra) and interleukin-1 receptor type I (IL-1R tI) in human preimplantation embryos and protein levels of interleukin-1 alpha (IL-1 alpha), IL-1 beta and IL1ra in human preimplantation embryo culture fluid have been correlated with successful implantation and pregnancy. Our aim in this study was to detect IL-1 beta, Il-1ra and Il-1R tI mRNA in single preimplantation mouse embryos and to describe the frequency of positive mRNA-expression at different developmental stages. B6C3F1-mice, 12 weeks old were pregnant mare serum gonadotropin (PMSG)/human chorionic gonadotropin (hCG)-stimulated and mated. Animals were sacrificed at day 0.5, and zygotes were flushed from the tubes and cultured in HAMs-F10 medium. 2-cell- (2C-), 8-cell- (8C-), morula- (M-), early blastocyst- (EB-) and hatching blastocyst- (HB-) stage embryos were examined by one round of reverse transcriptase (RT) followed by two rounds of polymerase chain reaction (PCR) carried out on individual mouse embryos for beta-actin (internal standard), IL-1 beta, IL-1ra and IL-1R tI-mRNAs. The frequencies of positive mRNA-expressions were as follows (2C/8C/M/EB/HB); beta-actin: 91/96/100/100/98%; IL-1b: 0/0/2.5/6.25/19; IL-1ra; 0/5/30/41/74% and IL-1R tI: 0/0/10/20/25%. The incidence of IL-1ra mRNA expression increased with developmental stage. IL-1ra mRNA seems to be expressed in a very high percentage (74%) of embryos near the time of implantation, whereas the percentage of IL-1 beta-mRNA positive embryos is surprisingly low (19%).

Animals↗
PubMed1997

Use of reverse transcription-polymerase chain reaction to detect embryonic interleukin-1 system messenger RNA in individual preimplantation mouse embryos co-cultured with Vero cells.

In this study, we report a total of 292 mouse embryos cultured on Vero cell monolayers and 77 embryos cultured in medium alone at different preimplantation stages examined individually for embryonic mRNA of beta-actin, interleukin-1beta (IL-1beta), interleukin-1 receptor antagonist (icIL-1ra) and interleukin-1 receptor type I (IL-1RtI) using reverse transcription and two-step polymerase chain reaction (RT-PCR). The rates of blastocyst formation and blastocyst hatching were both significantly higher in embryos co-cultured with Vero cells in comparison with the embryos cultured in control medium (81.2 +/- 2.6 versus 42.2 +/- 3.7%, P < 0.001; 75.6 +/- 2.7 versus 19.2 +/- 6.2%, P < 0.001 respectively). We have identified a similar pattern of interleukin-1 family embryonic mRNA transcripts expressed from the compact morula stage through to hatching blastocyst in both control and Vero cell cultured embryos with significantly increased icIL-1ra transcript at hatching blastocyst stage (P < 0.05, P < 0.001 respectively). There was a significant increase in IL-1beta mRNA transcripts of embryos at hatching blastocyst stage compared to compact morula stage in Vero cell cultured embryos (P < 0.05). These findings support the hypothesis that the IL-1 system is an important factor in embryo-maternal molecular communication during the implantation process.

Actins↗
PubMed1997

Interleukin 1 beta regulates Vero cell interleukin-1 receptor type I messenger ribonucleic acid expression.

Embryos cocultured with Vero cells display enhanced development in vitro. This could be due to an interaction between the embryo and cellular layer mediated by paracrine cytokines. The interleukin-1 (IL-1) system is composed of two IL-1 agonists, IL-1 receptor antagonist (IL-1ra), and two major IL-1 receptors (IL-1R tII). In this study, we measured Vero cell expression of IL-1 system mRNAs with reverse transcription polymerase chain reaction (RT-PCR) and validated the results with an immunohistochemistry study. RT-PCR revealed beta-actin and IL-1R tI mRNA expression in Vero cell cocultures without detectable IL-1 beta and IL-1ra mRNA expression. To determine the effect of IL-1 beta on IL-1R tI mRNA expression in Vero cells, quantitative competitive PCR methodology was developed. A competitive cDNA fragment was coamplified as an internal standard with the target cDNA sequence of IL-1R tI, showing a 50% decrease in Vero cell IL-1R tI cDNA cultured in the presence of IL-1 beta (100 IU/mI) compared to control Vero cell cultures (62.5 fg vs. 125 fg). Down-regulation of IL-1R tI mRNA by IL-1 beta is dose-dependent, with increasing concentrations (0-1000) IU/ml) of IL-1 beta producing progressive attenuation of IL-1R tI expression. Treatment with anti-IL-1 beta antibody ablate the inhibitory effect of IL-1 beta (100 IU/ml) on IL-1R tI mRNA expression. Immunostaining confirmed the presence of IL-1r tI protein in Vero cells. These results demonstrate the presence of IL-1 R tI in Vero cell monolayers and regulation of Il-1R tI mRNA by IL-1 beta.

Animals↗
PubMed1997

Embryonic regulation of integrins beta 3, alpha 4, and alpha 1 in human endometrial epithelial cells in vitro.

In the present study, we examined the embryonic regulation of beta 3 integrin in human endometrial epithelial cells (EEC) at the protein level and analyzed putative embryonic factors responsible for this regulation. The model employed is based on a clinical in vitro fertilization program in which single human embryos were cocultured with EEC until blastocyst stage and then transferred back to the uterus. After embryo transfer, EEC wells were divided according to the embryonic status reached: EEC with embryos that achieved the blastocyst stage, EEC with arrested embryos, and EEC without embryos. Immunostaining for beta 3 was positive in plasma membrane of EEC. Flow cytometry showed a mean percentage of beta 3-stained cells of 24.1 +/- 5.7 in EEC cocultured with embryos that achieved the blastocyst stage (n = 13) vs. 9.5 +/- 1.6 (P < 0.05) in those EEC cultured with arrested embryos (n = 12). Immunostaining for alpha 1 and alpha 4 integrins was negative in EEC monolayers studied, regardless of the presence or absence of embryos, and these findings were confirmed by flow cytometry. The possibility that the embryonic IL-1 system and leukemia inhibitory factor were involved in the endometrial beta 3 up-regulation was investigated by neutralizing experiments demonstrating a significant inhibition of beta 3-stained cells when EEC monolayers were cultured in the presence of EEC/blastocyst-conditioned media with (n = 4) vs. without (n = 8) antihuman interleukin (IL)-1 alpha + IL-1 beta (1.65% vs. 14.6%; P < 0.05). Dose-response experiments further demonstrated an up-regulation of beta 3 positive cells when IL-1 alpha + IL-1 beta were added to the medium at a concentration of 10 pg/mL compared with control medium without added cytokines (40% vs. 20%, n = 4). The functional relevance of the EEC beta 3 up-regulation was tested using a mouse blastocyst adhesion assay. More mouse blastocysts attached to EEC previously in contact with human blastocyst (72.7%) compared with those EEC previously in contact with arrested embryos (40%). Our results demonstrate the selective effect of a developing human embryo on EEC expression of beta 3, which is maximal when a human blastocyst instead of an arrested embryo is considered. Furthermore, the embryonic IL-1 system seems to be involved in the EEC beta 3 up-regulation, reinforcing the concept of precise paracrine cross-talk between blastocyst and endometrial epithelium during embryonic implantation.

Adult↗
PubMed1996

Hormonal regulation of serum and endometrial IL-1 alpha, IL-1 beta and IL-1ra: IL-1 endometrial microenvironment of the human embryo at the apposition phase under physiological and supraphysiological steroid level conditions.

We have investigated serum and intracavitary levels of IL-1 alpha, IL-1 beta and IL-1ra from agonadal women undergoing mock cycles (n = 20) of oocyte donation as a clinical model of controlled hormonal stimulation. Further, we compared the intracavitary IL-1 alpha, IL-1 beta and IL-1ra levels in the microenvironment of the human embryo at the apposition phase, day 5 after progesterone (P) administration using two different clinical models: oocyte donation (n = 20) which provides physiological steroid levels and a higher implantation rate per embryo, and in vitro fertilization (n = 6) with supraphysiological hormonal levels and a lower implantation rate.

Embryonic and Fetal Development↗
PubMed1996

Cytokines-adhesion molecules-invasive proteinases. The missing paracrine/autocrine link in embryonic implantation?

How implantation is regulated and brought about remains an enigma. The objective of the present review is to propose a hypothetical model based on our actual knowledge of the role of cytokines, adhesion molecules and invasive proteinases in the adhesion and invasion phases of embryonic implantation. For the purpose of clarity we will describe first what is known about the presence of these molecules in the endometrium and embryo in animal models and their relevance in embryonic implantation. Secondly, since human implantation is unique the presence of these factors in the human endometrium and embryo and their possible clinical relevance is considered separately. Finally, the link between cytokines, adhesion molecules and invasive proteinases as well as their endocrine/paracrine/autocrine regulation is put forward as a possible model that could lead us to a better understanding of the implantation process in humans.

Animals↗
PubMed1995

Gonadal steroids modulate interleukin-1 receptor antagonist mRNA expression in cultured human monocytes.

This study investigated whether gonadal steroids modulate the expression of the cytokine Interleukin-1 receptor antagonist in monocytes. Human male peripheral monocytes were isolated and cultured in serum free media with serially diluted concentrations of estradiol and progesterone. mRNA expressions with increasing steroid concentrations were compared by reverse transcription-polymerase chain reaction for intracellular and secretory interleukin-1 receptor antagonist specific primers and glyceraldehyde 3-phosphate dehydrogenase primers. Monocyte expression of secretory Interleukin-1 receptor antagonist mRNA was significantly elevated in the presence of normal physiological levels of estradiol (10(-11) M) and progesterone (10(-8) M), while expression was suppressed by higher concentrations of steroids. Intracellular receptor antagonist was also detected. This study is the first to describe the dose related response of cytokine interleukin-1 receptor antagonist to gonadal steroids.

Base Sequence↗
PubMed1995

Role of embryonic factors in human implantation.

Implantation biology is now at a stage where experimental science will be very productive in answering basic questions about the ability of an embryo to implant. The advancement of our knowledge of cytokines and growth factors has been critically important in fuelling the recent new understanding of embryo implantation. Specifically, our increased knowledge of the interleukin (IL)-1 system, as well as leukaemia-inhibiting factor (LIF), epidermal growth factor and colony-stimulating factor-1, and the availability of recombinant protein, specific antibodies and knockout mice, have led to a more detailed outline of implantation events. LIF and IL-1 are the two systems where recent advances have suggested their importance in implantation events. Recently, LIF has been shown in mice to be an endometrial requirement for implantation and embryo development. Although LIF is a pleiotropic molecule, with many interactions in multiple body tissues, in the uterus, concentrations are elevated on day 4 of pregnancy. Experiments with knockout mice have shown the requirement for endometrial LIF for successful implantation. The IL-1 system, consisting of two agonists (IL-1 alpha and IL-1 beta), two receptors (IL-1R types I and II) and the homologous IL-1 receptor antagonist (ra), has also been studied. Knowledge that the embryo secretes IL-1 suggested the interaction between embryonic IL-1 and endometrial receptor, which has been shown to occur. IL-1R type I is plentiful on endometrial epithelial cells and appears to interact with embryonically secreted IL-1 beta to favour implantation. Such implantation events in vivo in mice are blocked by the introduction of large quantities of IL-1ra, consistent with the hypothesis that appropriate interactions between agonist and receptor at the level of the endometrial surface are a requisite for successful implantation. As more specific information on each cytokine or growth factor system comes to light, more complete information on the multiple molecular steps of implantation will become apparent. However, it is clear that no single cytokine or growth factor will be able to explain the complicated events of embryo implantation. Such an important necessary phenomenon has multiple redundancies. The interactions between cytokines and growth factors are becoming increasingly apparent and will need more experimental evidence before a full understanding of implantation is available.

Embryo Implantation↗
PubMed1995

Interleukin-1 system crosstalk between embryo and endometrium in implantation.

Nowadays, cytokines and growth factors have become increasingly implicated in embryo implantation. Endometrial function, embryo secretions and embryo-endometrial interactions require a continuous dialogue and synchronism between both partners (endometrium and embryo), not only at the endocrine level but also at the local (paracrine/autocrine) level. This review focuses on the interleukin-1 system as an example of a local regulator in embryo implantation. Evidence demonstrating its presence and relevance to human endometrial physiology and human embryo development is presented. Finally, we show data which suggest the possible role of this cytokine in implantation.

Cell Communication↗
PubMed1995

Immunohistochemical localization, identification and regulation of the interleukin-1 receptor antagonist in the human endometrium.

There is evidence suggesting the importance of the interleukin-1 receptor type I (IL-1Rtl) and interleukin-1 beta (IL-1 beta) as mediator in local intercellular interactions in endometrial tissue and embryonic implantation. To complete our understanding of the entire endometrial IL-1 system in humans, we have investigated the immunohistochemical distribution of IL-1 receptor antagonist (IL-1ra) in the human endometrium throughout the menstrual cycle. We have also identified the forms of IL-1ra present in human endometrial cells. Immunoreactive IL-1ra was found in both cryostat and paraffin-embedded sections of human endometrium using the alkaline phosphatase-peroxidase (A-P) method with two different IL-1ra antibodies. IL-1ra was present throughout the entire menstrual cycle, located primarily in the endometrial epithelium. However, IL-1ra staining was significantly higher during follicular phase in comparison with early and mid-late luteal phases. Reverse transcriptase polymerase chain reaction of cultured stromal and glandular cells showed that these cells express the intracellular form of IL-1ra mRNA (icIL-1ra). Our results demonstrate the regulated presence of the icIL-1ra in the human endometrium. This finding supports a possible autocrine-paracrine role for the IL-1 system in the human endometrium and embryonic implantation.

Adult↗
PubMed1994

Interleukin-1 in human ovarian cells and in peripheral blood monocytes increases during the luteal phase: evidence for a midcycle surge in the human.

OBJECTIVE: Resident ovarian macrophages are thought to be critically involved in cyclic ovarian events. A prominent macrophage product, interleukin-1, has been shown to affect ovarian cell function. In this report we present evidence for an intrafollicular periovulatory interleukin-1 surge. Additionally, we demonstrate that interleukin-1 beta messenger ribonucleic acid in peripheral blood monocytes increases threefold during the luteal phase of the menstrual cycle over that found in the follicular phase. STUDY DESIGN: Follicular fluid cells isolated as a byproduct of transvaginal oocyte retrievals in gonadotropin-stimulated in vitro fertilization cycles were immunoprobed for the presence of interleukin-1 protein. Late follicular phase cumulus and granulosa cells obtained from an aspirated preovulatory follicle were likewise probed. RESULTS: Although the in vitro fertilization-retrieved cells stained positive for interleukin-1 protein, the late follicular phase cells were devoid of the protein. Granulosa cells from in vitro fertilization cycles were examined for interleukin-1 protein binding sites with iodinated interleukin-1 alpha protein. These cells were found to have approximately 2000 binding sites per cell. Poly A+ messenger ribonucleic acid isolated from peripheral blood monocyte samples from women during the follicular and luteal phases and from male controls were probed for interleukin-1 ribonucleic acid content by means of Northern analysis. The luteal samples contained a threefold higher interleukin-1 messenger ribonucleic acid content that did the follicular phase samples or the controls. CONCLUSION: The ovarian interleukin-1 protein increase taken together with increased peripheral blood monocyte interleukin-1 messenger ribonucleic acid suggests that interleukin-1 production increases at midcycle.

Female↗
PubMed1994

Gene regulation of interleukin-1 beta, interleukin-1 receptor type I, and plasminogen activator inhibitor-1 and -2 in human granulosa-luteal cells.

OBJECTIVE: To investigate the regulation of messenger ribonucleic acid (mRNA) levels of interleukin-1 beta (IL-1 beta), interleukin-1 (IL-1) receptor type 1, and plasminogen activator (PA) inhibitor-1 and -2 in cumulus cells, granulosa-luteal cells, and macrophage-depleted granulosa-luteal cells obtained from human preovulatory follicles. DESIGN: Prospective longitudinal study. SETTING, PATIENTS: Patients undergoing assisted reproductive technologies (ART) in the Department of Gynecology and Obstetrics, Stanford University, Stanford, California. INTERVENTIONS: Cumulus cells and granulosa-luteal cells were collected by ultrasound-guided transvaginal aspiration at the time of ART. MAIN OUTCOME MEASURES: Northern blot analysis of mRNA levels of IL-1 beta, IL-1 receptor type 1, PA inhibitor-1 and -2 in cumulus cells, granulosa-luteal cells and macrophage-depleted granulosa-luteal cells, and indirect immunocytochemical analysis of the IL-1 system and macrophages in granulosa-luteal cell preparations were performed. RESULTS: Interleukin-1 beta mRNA levels in uncultured cumulus cells were less than those of uncultured granulosa-luteal cells with no differences in IL-1 receptor type 1 mRNA levels between these two cell types. Granulosa-luteal cell IL-1 receptor type 1 mRNA levels were expressed constitutively throughout 24 hours of culture with no effect by hCG, whereas IL-1 beta mRNA levels increased within 6 hours, and then remained elevated for 24 hours with no effect by hCG. Interleukin-1 beta significantly increased granulosa-luteal cell mRNA levels of IL-1 beta (over twofold), IL-1 receptor type 1 (over twofold), PA inhibitor-1 (approximately 1.4-fold), and PA inhibitor-2 (approximately 1.6-fold). In contrast, IL-1 beta had no effect on IL-1 beta and IL-1 receptor type 1 mRNA levels in macrophage-depleted granulosa-luteal cells. Granulosa-luteal cells, not macrophages, account for the majority of the immunocytochemical staining for IL-1 beta and IL-1 receptor type 1 in follicular aspirates. CONCLUSIONS: These studies suggest that the IL-1 system is regulated in human granulosa-luteal cells during the periovulatory period. Furthermore, the augmentation of PA inhibitor-1 and -2 mRNA levels by IL-1 beta suggests a potential role for IL-1 beta in remodeling of the human ovary during the periovulatory period.

Adult↗
PubMed1994

Immunohistochemical localization of the interleukin-1 system in the mouse ovary during follicular growth, ovulation, and luteinization.

The distribution of immunoreactive interleukin-1 receptor type I (IL-1R tI), IL-1 alpha, and IL-1 beta, and of macrophages, was investigated immunohistochemically in the mouse ovary during follicular growth, ovulation, and luteinization. For this purpose, an indirect immunofluorescence technique, using specific monoclonal antibodies against mouse IL-1R tI, mouse IL-1 alpha, IL-1 beta, and macrophage antigens (CD11b/CD18) was used with sections of paraffin-embedded ovaries from eCG and eCG/hCG-treated 12-wk-old B6C3F-1 female mice. During follicular development, IL-1 alpha, IL-1 beta, and IL-1R tI staining were confined to the theca-interstitial layer of growing follicles with one remarkable exception. Intense IL-1R tI still staining was present in the cytoplasm and plasma membrane of the murine oocyte. During ovulation, IL-1 alpha and IL-1 beta were still confined to the theca layer, but faint IL-1R tI staining was initiated in cumulus cells and in granulosa cells just before follicle rupture. Immediately after follicle rupture, granulosa cells stained positive for IL-1R tI, IL-1 alpha, and IL-1 beta. During luteinization, granulosa-luteal cells of the corpus luteum demonstrated strong IL-1R tI, IL-1 alpha, and IL-1 beta staining. Macrophages were detected in the theca layer and stroma, but never within the follicle before ovulation. Immediately after ovulation, there was a rapid entry of macrophages into the follicle, and macrophages were also present inside the corpus luteum. Our morphological results support a possible autocrine-paracrine role of the mouse ovarian IL-1 system in ovulation and luteinization.

Animals↗
PubMed1994

Interleukin-1 receptor antagonist suppresses human chorionic gonadotropin-induced ovulation in the rat.

Indirect evidence has implicated the interleukin-1 (IL-1) system in ovulation. Thus, the ability of IL-1 beta to induce ovulation in rat and rabbit perfused ovaries has been demonstrated. In the present study, the involvement of the IL-1 system in ovulation was directly tested in vivo, in the rat model. For this purpose, the natural inhibitor of the IL-1 system, interleukin-1 receptor antagonist (IL-1ra), was administered locally by use of an intrabursal injection route. Twenty-six-day-old Sprague-Dawley rats received injections of eCG (10 IU), followed 56 h later by hCG (15 IU). IL-1ra (75 micrograms/bursa) was administered locally into the periovarian sac, 6 h (n = 5), 2 h (n = 11), and 0 h (n = 5) before hCG administration. Control animals (n = 10) received injections of the same volume (50 microliters) of vehicle (PBS). IL-1ra administered locally into the periovarian sac inhibited ovulation from the treated ovary, reaching 40% inhibition (p < 0.05) when injected 2 h prior to hCG, as compared to the untreated contralateral ovary (6 +/- 1.4 ova vs. 10 +/- 1.8 ova) and PBS-injected control ovaries (6 +/- 1.4 ova vs. 8.2 +/- 0.7). Injection of IL-1ra 6 h before or concomitantly with hCG did not affect the ovulation rate. Internucleosomal DNA fragmentation was evaluated by 3' end-labeling and autoradiography for detecting apoptotic changes. No difference in DNA fragmentation was found between treated and untreated ovaries.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Embryonic implantation in mice is blocked by interleukin-1 receptor antagonist.

We have investigated the relevance of interleukin-1 receptor type I (IL-1R tI) in the implantation process in vivo in a murine model. Indirect immunofluorescence experiments demonstrate that IL-1R tI is located in mouse endometrial lumenal epithelium with increased intensity in the periimplantation period, whereas IL-1 beta staining is located in the mouse placenta. PMSG/human CG (hCG)-stimulated and mated 12-week-old B6C3F-1 female mice were randomly allocated to three groups: A, control noninjected; B, buffer-injected animals; and C, animals injected ip with 20 micrograms recombinant human IL-1 receptor antagonist (rhIL-1ra) every 12 h beginning on pregnancy day 3. Injections were continued until day 9, and animals were killed 12 h after the last injection. Pregnancy rates in the three groups were: noninjected, 58.8% (10 of 17); buffer-injected, 73.7% (14 of 19); rhIL-1ra-injected, 6.7% (1 of 15), P = 0.0001155, Fisher exact test. To rule out the possibility that pregnancy failure was due to an embryotoxic effect of rhIL-1ra, 2-cell mouse embryos (n = 276) were flushed from the same group of animals used for in vivo experiments and cultured with increasing concentrations of rhIL-1ra: 0 microgram/ml (n = 91), 1 microgram/ml (n = 36), 50 micrograms/ml (n = 36), 100 micrograms/ml (n = 52), and 200 micrograms/ml (n = 61) rhIL-1ra. The percentages of 2-cell mouse embryos reaching the blastocyst stage after 72 h in culture were 85.7%, 91.6%, 94.4%, 96%, and 85.2%, respectively. We further cultured these blastocysts for 5 days on fibronectin-coated plates with or without 200 micrograms/ml rhIL-1ra. In both groups, hatching, attachment to fibronectin, outgrowth, and migration were documented to be similar. Furthermore, our longitudinal morphological study of embryonic implantation in control and rhIL-1ra-injected mice shows that the blockade of IL-1R tI interferes with the attachment of mouse blastocysts to maternal endometrium in vivo. In summary, we demonstrate that blockade of maternal endometrial IL-1R tI with IL-1ra prevents implantation in the mouse by interfering with embryonic attachment, without adverse effects on blastocyst formation, hatching, fibronectin attachment, outgrowth, and migration in vitro.

Animals↗