| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Article |
vß3 Integrin Adversely Affects Implantation in the Mouse1
a Department of Physiology, School of Veterinary Medicine, Universidad Complutense, 28040 Madrid, Spain
b Lexicon Genetics, Inc., The Woodlands, Texas 77381
c Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology, University of North Carolina, Chapel Hill, North Carolina 27599
 |
ABSTRACT |
|---|
 TOP ABSTRACT INTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
vß3 integrin on both embryo and endometrium in women and mice coincides with the time of initial attachment during implantation. In mice, the endometrial and embryonic vß3 integrin is present at the time of implantation, as shown by reverse transcription-polymerase chain reaction and immunohistochemistry. In situ hybridization demonstrates the presence of the vß3 integrin on the subluminal stromal cells of the uterus. Functional blockade of this integrin on the day of implantation by intrauterine injection of neutralizing monoclonal antibodies against v or ß3 integrin subunits, arg-gly-asp (RGD)-containing peptides, or of the disintegrin echistatin, reduced the number of implantation sites compared to controls receiving BSA. These studies demonstrate that, like the human, the murine vß3 integrin is expressed at the time of implantation in the endometrium and on the blastocyst, and may play a critical role in the cascade of events leading to successful implantation.
|
INTRODUCTION |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
vß3 integrin has increased as a result of a number of earlier studies that correlate its expression with the window of implantation [6], and its absence with certain types of infertility including luteal phase defect [4], endometriosis [12], hydrosalpinx [13], and unexplained infertility [14]. Recent studies by Simón et al. have demonstrated that embryonic signaling may stimulate the expression of this integrin in the mouse [15] and human [16] endometrium as well.
Rodents appear to be excellent models for studying implantation and the role of cytokines, growth factors, and other factors during implantation. Integrin expression has been shown to be regulated during the estrous cycle in rats [17, 18], and several factors have been shown to be essential for normal implantation in the mouse and rat [19–23]. Implantation in the mouse has been shown to involve extracellular matrix and specifically the three amino-acid peptide sequence, arg-gly-asp (RGD) [24–28]. In these studies, RGD has been shown to block trophoblast attachment and outgrowth both in vivo and in vitro. As this amino acid combination forms the ligand recognition sequence for the vß3 integrin, we have examined the expression of this integrin during early pregnancy in the mouse, and reported a temporal expression that is similar to that of leukemia inhibitory factor (LIF) [18]. In the present study, we expand on these findings by neutralization of this integrin during the time of implantation in the mouse model.
|
MATERIALS AND METHODS |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
Virgin 6- to 8-wk-old female CD1 mice (Charles River Laboratories, Raleigh, NC) were housed in the animal care facility in rooms with a controlled light schedule (14L:10D) and controlled temperature range (22–24°C), and were fed ad libitum. Females were bred with CD1 males and checked the following morning for vaginal plugs. The day of vaginal plug was recorded as Day 1 of pregnancy.
Immunohistochemistry
Embryos were obtained from 3 female mice after i.p. injection of 7.5 IU eCG. After 48 h, the mice received an i.p. injection of 7.5 IU hCG and were mated. The mice were killed on the morning of Day 4, and embryos were harvested by laparotomy and flushing of the uterine horns. Immunohistochemistry was performed using biotin-labeled v specific (biotinylated anti-mouse CD51; PharMingen, San Diego, CA) or ß3 specific antibodies (fluorescein isothiocyanate-labeled anti-mouse CD61; PharMingen). The embryos were placed in Biocoat Insert Controls (Becton Dickinson, Franklin Lakes, NJ) during the entire staining process. Embryos were fixed with 2% paraformaldehyde in PBS pH 7.2 with 10% sucrose for 15 min and then rinsed two times with PBS. Embryos were treated with 2% hamster serum in PBS for 30 min to block nonspecific staining, then placed in primary antibody overnight at 4°C (1:10 dilution for v or ß3 in 1% hamster serum). The embryos were then rinsed twice with PBS and incubated with avidin-Texas Red (Vector, Burlingame, CA; 1:200 dilution in PBS) for 30 min at room temperature (RT). The embryos were rinsed twice with PBS and then fixed a final time with 2% paraformaldehyde in PBS with 10% sucrose and again rinsed twice with PBS. The Biocoat Insert Control filters were cut out of the plastic containers and placed on a slide, coverslips were placed, and the slides were viewed under a fluorescence microscope. Uteri from Day 4 pregnant mice were snap-frozen in liquid nitrogen, and immunohistochemistry was performed on cross sections for v and ß3 integrin subunits.
Reverse Transcription (RT)-Polymerase Chain Reaction (PCR) Assays
Poly(A)+ RNA was isolated from mouse embryos and uteri using the Micro-Fast kit (Invitrogen, Carlsbad, CA), from which single-strand cDNA was synthesized using the cDNA cycle kit (Invitrogen). One half microliter of cDNA was used per 50 µl PCR reaction. The reaction mixture contained 100 mM Tris-HCL pH 9.0; 500 mM KCL; 1% Triton X-100; 2 mM MgCl2; 0.2 mM each of dATP, dGTP, dCTP, dTTP; and 0.5 U Taq DNA polymerase (Promega, Madison, WI). The primers used for PCR are shown in Table 1 along with the expected size of the product based on primer location. PCR amplification was performed by a three-step process: 1) initial denaturation at 95°C, for 10 min; 2) annealing at 60°C for 2 min and extension at 72°C for 3 min; and 3) final extension at 72°C for 10 min. The amplified products were separated on 1% agarose gels using a 1-kilobase (kb) DNA ladder (Promega) for size comparison. The cDNA probes for v and ß3 subunits were generated by RT-PCR using primers previously described [18] (Table 1).
|
In Situ Hybridization
A hybridization-digoxigenin staining protocol was used according to the method of Schaeren-Wiemers and Gerfin-Moser [29]. Briefly, uteri from pregnant CD-1 females were excised, placed directly in OCT Tissue Tek (Bayer Corp., Elkhart, IN), frozen on dry ice, sectioned in a cryostat at 10-µm-thick sections, and collected onto ribonuclease (RNase)-free Fisherbrand Plus glass microscope slides (Fisher Scientific, Pittsburgh, PA). Slides were air-dried for 20 min to 3 h. Sections were fixed for 10 min at 25°C in 4% paraformaldehyde in PBS, washed 3 times in PBS, and acetylated using a solution of acetic anhydride. Hybridization buffer (50% formamide, 5-strength SSC [single-strength SSC is 0.15 M sodium chloride, 0.015 M sodium citrate], 5-strength Denhardt's solution, 250 µg/ml yeast RNA, and 500 µg/ml herring sperm DNA) was placed on each section and incubated for 2 h at RT in a 5-strength SSC humidified chamber. The hybridization buffer was removed and replaced with fresh hybridization buffer containing 200–400 ng/ml of digoxigenin-labeled sense and antisense RNA probes (see above). Sections were covered with a coverslip, and samples were incubated in humidified 5-strength SSC, 50% formamide at 72°C. After hybridization, the coverslips were removed, and the specimens were transferred first into 0.2-strength SSC at 72°C for 1 h, and then into 0.2-strength SSC at 25°C for 5 min to remove unbound probe. Slides were placed in a blocking buffer (0.1 M Tris pH 7.6, 0.15 M NaCl containing 1% heat-inactivated goat serum) for 1 h at RT in a humidified chamber. After the blocking buffer was poured off, anti-digoxigenin antibody (1:5000 dilution; Fab fragment conjugated to alkaline phosphatase; Boehringer Mannheim, Indianapolis, IN) was added, and samples were incubated at 4°C overnight. After extensive washing in 0.1 M Tris pH 9.4, 0.1 M NaCl, and 50 mM MgCl2 to reduce background, the color reaction was carried out for 6 h to 3 days at RT using 4-nitro blue tetrazolium chloride (NBT; Boehringer Mannheim), 5-bromo-4-chloro-3-indolyl-phosphate (BCIP; Boehringer Mannheim), and levamisole (Sigma Chemical Co., St. Louis, MO) in dimethylformamide. Samples were mounted with glass coverslips using Aquamount (Baxter Scientific, Westchester, PA).
Digoxigenin-labeled RNA sense and antisense probes (~10 µg) were prepared by mixing 10-strength transcription buffer (Promega), 0.2 M dithiothreitol, digoxigenin nucleotide mix (Boehringer Mannheim; 10 mM GTP, 10 mM ATP, 10 mM CTP, 6.5 mM UTP, 3.5 mM digoxigenin-UTP, pH 8.0), 1 µg of linearized ß3 integrin cDNA, placental RNase inhibitor (100 U/ml), and SP6, T7, or T3 RNA polymerase (10 U/ml; Promega). The synthesis of probe was monitored by electrophoresis of an aliquot through a 1% agarose Tris-borate-EDTA gel (with 0.5 mg/ml ethidium bromide). An RNA band ~10-fold more intense than the plasmid band indicated the successful synthesis of the probe. Deoxyribonuclease (RNase-free; Promega) was added to the digoxigenin RNA synthesized probes and incubated for 15 min at 37°C. A solution containing 50 mM Tris, 1 mM EDTA pH 8.0, 10 µl 4 M LiCl, and 300 µl ethanol was added to the probes, mixed, and maintained at -20°C for 30 min. RNA was pelleted and dried.
Function Blocking Studies
To determine whether the vß3 integrin may play a role in implantation, we investigated the effect of blocking this integrin using intrauterine injection of various bioactive compounds on the day of implantation. After coitus and documentation of a vaginal plug, each female underwent midventral laparotomy on Day 4 of pregnancy between 0900 and 1100 h. The right horn of each mouse was fixed with forceps, and the needle was very slowly introduced as close as possible to the cervix into the uterine horn. One of the following substances was injected into the right horn of each animal: the v-specific neutralizing monoclonal antibody (H9.1C; PharMingen; 0.2 or 4 µg in 100 µl; n = 10), the neutralizing antibody against ß3 subunit (2C9.G2; PharMingen; 5 µg in 100 µl; n = 3), echistatin (Sigma; 0.1 or 0.5 µg in 100 µl; n = 10), RGD-containing hexapeptides (GRGDSP; Gibco, Grand Island, NY; 200–500 µg in 100 µl in 0.9% saline; n = 11), and a non-RGD sequence (GRGESP; Gibco; 500 µg in 100 µl in 0.9% saline; n = 4). The total amount of each injection was infused slowly over 3 min, injected from the cervix toward the uterotubal junction. Each animal served as her own control, with the left uterine horn receiving 100 µl of 0.9% saline. As controls, some pregnant females received 500 µg BSA in 100 µl of 0.9% saline into the right horn (n = 5). On Day 7 of pregnancy, all animals were killed, the uteri were removed by laparotomy, and the number of implants was counted in each uterine horn.
Statistical Comparisons
The numbers of implantation sites were compared between groups. Data are presented as percentage of control, comparing the number of implantation sites in the left (control) horn to the right (treatment) horn. Overall statistical comparison was made of the number of implantation sites in the treated horn, between groups, using ANOVA with Scheffe's correction for multiple comparisons.
|
RESULTS |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
v and ß3 subunits was examined first with RT-PCR, as shown in Figure 1. Both subunits were present on mouse blastocysts (upper panel) and on the endometrium of mice at the time of implantation (lower panel). As seen in Figure 2, the localization of expression of the vß3 integrin was shown in both blastocyst (A) and endometrium (B), using the ß3 specific antibody, 2C9.G2. The pattern was similar using both v and ß3 specific monoclonal antibodies. While the embryo was uniformly positive, the endometrium expressed this integrin in the subluminal stroma as previously reported [15, 18]. This pattern of expression was also shown by in situ hybridization (Figure 3), using the specific ß3 antisense strand, with specific staining localized in the stromal cells immediately below the luminal surface. Only nonspecific labeling was seen using the ß3 sense probe.
|
|
|
To investigate the potential role of vß3 on implantation using the mouse model, several reagents that specifically block the ability of this integrin to bind ligand were injected into the uterine horn at the time of initial attachment on the morning of Day 4 of pregnancy (Fig. 4A). Injections of BSA (bar 1) were compared to immunologic neutralization with v specific monoclonal antibody (H9.2B8; bar 2) or ß3 specific antibody (2C9.G2; bar 3); the snake venom disintegrin, echistatin (bar 4), which specifically inactivates the vß3 integrin; or competitive inhibition with peptides containing the RGD sequence (GRGDSP; bar 5). As a secondary control, some animals received the non-RGD-containing peptides (GRGESP; bar 6). In each case the contralateral horn served as an internal control. As shown in Figure 4C, mouse uteri from controls receiving BSA contained 6–8 implanted embryos in the injected right uterine horn similar to the left control horn. In a typical experiment, when one uterine horn received injection of substances that neutralize or block vß3 integrin activity, there was a significant reduction in the number of implantation sites in that experimental horn (injection of RDG peptides into the right horn; Fig. 4B). Normal or near normal implantation rates were seen in the saline-injected left uterine horn. Using ANOVA with Scheffe's correction, there was an overall significant difference in the number of implantation sites between groups (P < 0.0001). RGD (bar 4), and echistatin (bar 5) resulted in significant reduction in the number of implants compared to those in the non-injected horn (P = 0.024 and 0.02, respectively). Injection with the monoclonal antibody against the v subunit, H9.2B8 (bar 2) and the anti-ß3 antibody (2C9.G2; bar 3) reduced the number of implantation sites, but this did not reach significance (P = 0.07).
|
The effect of these reagents was found to be dose-dependent (Fig. 5). Comparison of 0.2 µg/ml of the anti-v antibody H9.1C to a higher concentration of 4 µg/ml showed little difference. Marginal differences were noted in implantation site numbers using different concentrations of echistatin (0.1 vs. 0.5 µg/ml; P = 0.0.1), and a significant difference was noted using high vs. low concentrations of RDG peptide (20 vs. 50 µg/ml; P < 0.04). The higher dose of each reagent resulted in a significant reduction in the number of implantation sites compared to the BSA control sites (all < 0.01). It is likely that the "low" concentration of the neutralizing antibody was already saturating, and this prevented us from observing a true dose response using that chosen dose of the anti-v antibody H9.1C.
|
|
DISCUSSION |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
vß3 integrin appears to be specifically present in the endometrium during the window of implantation in both humans and mice. Ligand binding to vß3 is dependent on the three-amino acid sequence arg-gly-asp (RGD), which is involved in embryo attachment and outgrowth in vivo [24–27]. In addition, studies have been reported to suggest the involvement of RGD in implantation in vivo [28].
Studies from other species suggest that RGD and integrin expression at the time of implantation may define the period of receptivity. In the human, the vß3, 4ß1, and 1ß1 integrins are all co-expressed during the putative window of implantation on Days 20–24 [6]. Integrin and extracellular matrix expression has also been examined in several large animal models. In the sheep, vß3 and its putative ligand osteopontin are both expressed during the periimplantation period [30]. Porcine endometrium has been shown to express a different complement of integrins, including regulation of 5ß1 integrin [31]. The baboon also expresses the vß3 integrin, but the timing of its expression is delayed [32]. These differences in RGD-dependent integrin expression may ultimately be shown to contribute to the differences noted between temporal and spatial patterns of placental invasion that exists between these species.
Competitive inhibition of the vß3 integrin binding site by RGD-containing peptides or neutralization with disintegrins and monoclonal antibodies significantly reduced the number of implantation sites observed in the treated uterine horn compared to the untreated horn and to controls receiving a non-RGD peptide or BSA. Not all evidence supports a critical role of the vß3 vitronectin receptor in implantation. The mouse null mutant for vß3 is fertile and undergoes implantation, even though the embryos have reduced survival and placental defects [33]. This finding in the null mutant mouse may represent developmental compensation, given the presence of alternative ß subunits, such as ß5, which can also pair with v. Glanzmann's thromboasthenia patients who have a mutation in the ß3 subunit of the IIb/ß3 platelet integrin have platelet dysfunction but remain fertile. The bones of such patients are also normal. Since osteoclasts normally employ the vß3 for osteoclast-mediated remodeling, this finding suggests that other v integrins (vß5 or vß6) can compensate for and restore normal osteoclast function when the ß3 integrin is missing or dysfunctional.
In light of these controversies, our findings should be interpreted with caution. Injection of function-perturbing agents could interfere with implantation at many levels. Embryonic integrin function may be the target of our intervention, disrupting embryo survival or function. It was recently shown that RGD peptides block mouse embryo attachment to human endometrial stromal cells [34]. Our studies and those of others have shown that the ß3 subunit is present on the outer surface of the mouse [3] and human [2] blastocyst. Cheresh and coworkers [35] have demonstrated that vß3 integrin is critical for angiogenesis. Neutralization of this integrin at the time of implantation could reduce embryo survival by preventing new vessel formation at the site of implantation and could account for the reduced number of implantation sites following injection of integrin neutralization agents.
In summary, the expression of embryonic and endometrial vß3 integrin during the window of implantation in the mouse suggests that this molecule does play a role in the implantation process. As previously shown both in vitro and in vivo, RGD peptides are competitive inhibitors of certain integrins and may interfere with implantation-mediated events. Our study further supports a role for vß3 integrin in this process and suggests a potentially critical function for this integrin in endometrial-embryo interactions. Targeting integrins may provide a new avenue for the development of contraceptive technologies, and the loss of this integrin in certain infertility states may signify the presence of implantation defects that reduce cycle fecundity in women.
|
FOOTNOTES |
|---|
1 Financial support provided by National Institutes of Health grants HD 35041 and HD-34824–1 (B.A.L.). This work was supported in part by the National Cooperative Program on Markers of Uterine Receptivity and the Fogerty International Fellowship Program (Y.G.). Sabbatical stay supported by Subprograma general de estancias en el extrajero grant from the Spanish Governnment, Ministry of Science and Education, Madrid, Spain. 
2 Correspondence: Bruce A. Lessey, CB #7570 MacNider Bldg., University of North, Carolina, Chapel Hill, NC 27599. FAX: 919 966 5214; lessey{at}med.unc.edu
Accepted: December 13, 1999.
Received: October 4, 1999.
|
REFERENCES |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
v are apically distributed in endometrial epithelium. Mol Hum Reprod 1996; 2:527–534.4, and 1 in human endometrial epithelial cells in vitro. J Clin Endocrinol Metab 1997; 82:2607–2616.vß3 integrin expression in the uterus and conceptus during the peri-implantation period. Biol Reprod 1999; 61:892–899.v/ß3 for angiogenesis. Science 1994; 264:569–571.This article has been cited by other articles:
|
|
 |
|
  R. C Burghardt, J. R Burghardt, J. D Taylor II, A. T Reeder, B. T Nguen, T. E Spencer, K. J Bayless, and G. A Johnson Enhanced focal adhesion assembly reflects increased mechanosensation and mechanotransduction at maternal-conceptus interface and uterine wall during ovine pregnancy Reproduction, March 1, 2009; 137(3): 567 - 582. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. J White, R. C Burghardt, J. Hu, M. M Joyce, T. E Spencer, and G. A Johnson Secreted phosphoprotein 1 (osteopontin) is expressed by stromal macrophages in cyclic and pregnant endometrium of mice, but is induced by estrogen in luminal epithelium during conceptus attachment for implantation. Reproduction, December 1, 2006; 132(6): 919 - 929. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H.-C. Ruan, X.-M. Zhu, Q. Luo, A.-X. Liu, Y.-L. Qian, C.-Y. Zhou, F. Jin, H.-F. Huang, and J.-Z. Sheng Ovarian stimulation with GnRH agonist, but not GnRH antagonist, partially restores the expression of endometrial integrin beta3 and leukaemia-inhibitory factor and improves uterine receptivity in mice Hum. Reprod., October 1, 2006; 21(10): 2521 - 2529. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. S. Daftary and H. S. Taylor Endocrine Regulation of HOX Genes Endocr. Rev., June 1, 2006; 27(4): 331 - 355. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. P. Ramos, B. R. Rueda, P. C. Leavis, and R. R. Gonzalez Leptin Serves as an Upstream Activator of an Obligatory Signaling Cascade in the Embryo-Implantation Process Endocrinology, February 1, 2005; 146(2): 694 - 701. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. E Spencer, G. A Johnson, F. W Bazer, and R. C Burghardt Implantation mechanisms: insights from the sheep Reproduction, December 1, 2004; 128(6): 657 - 668. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Y Lee and F. J DeMayo Animal models of implantation Reproduction, December 1, 2004; 128(6): 679 - 695. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. K. Dey, H. Lim, S. K. Das, J. Reese, B. C. Paria, T. Daikoku, and H. Wang Molecular Cues to Implantation Endocr. Rev., June 1, 2004; 25(3): 341 - 373. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. I. Rodriguez, J.-G. Cheng, L. Liu, and C. L. Stewart Cochlin, a Secreted von Willebrand Factor Type A Domain-Containing Factor, Is Regulated by Leukemia Inhibitory Factor in the Uterus at the Time of Embryo Implantation Endocrinology, March 1, 2004; 145(3): 1410 - 1418. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. A. Johnson, R. C. Burghardt, F. W. Bazer, and T. E. Spencer Osteopontin: Roles in Implantation and Placentation Biol Reprod, November 1, 2003; 69(5): 1458 - 1471. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Nagaoka, H. Nojima, F. Watanabe, K.-T. Chang, R. K. Christenson, S. Sakai, and K. Imakawa Regulation of Blastocyst Migration, Apposition, and Initial Adhesion by a Chemokine, Interferon {gamma}-inducible Protein 10 kDa (IP-10), during Early Gestation J. Biol. Chem., August 1, 2003; 278(31): 29048 - 29056. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. A. Johnson, R. C. Burghardt, M. M. Joyce, T. E. Spencer, F. W. Bazer, C. A. Gray, and C. Pfarrer Osteopontin Is Synthesized by Uterine Glands and a 45-kDa Cleavage Fragment Is Localized at the Uterine-Placental Interface Throughout Ovine Pregnancy Biol Reprod, July 1, 2003; 69(1): 92 - 98. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K.B.C. Apparao, M. J. Illera, S. A. Beyler, G. E. Olson, K. G. Osteen, M. H. Corjay, K. Boggess, and B. A. Lessey Regulated Expression of Osteopontin in the Peri-Implantation Rabbit Uterus Biol Reprod, May 1, 2003; 68(5): 1484 - 1490. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Zhang, Y.-G. Zhao, Y.-J. Cao, Q.-X. A. Sang, and E.-K. Duan Expression and implications of tissue inhibitor of metalloproteinases-4 in mouse embryo Mol. Hum. Reprod., March 1, 2003; 9(3): 143 - 149. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Inagaki, C. Stern, J. McBain, A. Lopata, L. Kornman, and D. Wilkinson Analysis of intra-uterine cytokine concentration and matrix-metalloproteinase activity in women with recurrent failed embryo transfer Hum. Reprod., March 1, 2003; 18(3): 608 - 615. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Illera, P.L. Lorenzo, Y.-t. Gui, S. A. Beyler, K.B.C. Apparao, and B. A. Lessey A Role for {alpha}v{beta}3 Integrin During Implantation in the Rabbit Model Biol Reprod, March 1, 2003; 68(3): 766 - 771. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. C. Ajonuma, L. N. Chan, E. H. Y. Ng, P. H. Chow, L. S. Kung, A. N. Y. Cheung, C. Briton-Jones, I. H. Lok, C. J. Haines, and H. C. Chan Characterization of epithelial cell culture from human hydrosalpinges and effects of its conditioned medium on embryo development and sperm motility Hum. Reprod., February 1, 2003; 18(2): 291 - 298. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Kabir-Salmani, S. Shiokawa, Y. Akimoto, H. Hasan-Nejad, K. Sakai, S. Nagamatsu, K. Sakai, Y. Nakamura, A. Hosseini, and M. Iwashita Characterization of Morphological and Cytoskeletal Changes in Trophoblast Cells Induced by Insulin-Like Growth Factor-I J. Clin. Endocrinol. Metab., December 1, 2002; 87(12): 5751 - 5759. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Rosbottom, C. L. Scudamore, H. von der Mark, E. M. Thornton, S. H. Wright, and H. R. P. Miller TGF-{beta}1 Regulates Adhesion of Mucosal Mast Cell Homologues to Laminin-1 Through Expression of Integrin {alpha}7 J. Immunol., November 15, 2002; 169(10): 5689 - 5695. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Creus, J. Ordi, F. Fabregues, R. Casamitjana, B. Ferrer, E. Coll, J. A. Vanrell, and J. Balasch {alpha}v{beta}3 integrin expression and pinopod formation in normal and out-of-phase endometria of fertile and infertile women Hum. Reprod., September 1, 2002; 17(9): 2279 - 2286. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Basak, R. Dhar, and C. Das Steroids Modulate the Expression of {alpha}4 Integrin in Mouse Blastocysts and Uterus During Implantation Biol Reprod, June 1, 2002; 66(6): 1784 - 1789. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Strandell and A. Lindhard Why does hydrosalpinx reduce fertility?: The importance of hydrosalpinx fluid Hum. Reprod., May 1, 2002; 17(5): 1141 - 1145. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. B. C. Apparao, M. J. Murray, M. A. Fritz, W. R. Meyer, A. F. Chambers, P. R. Truong, and B. A. Lessey Osteopontin and Its Receptor {alpha}v{beta}3 Integrin Are Coexpressed in the Human Endometrium during the Menstrual Cycle But Regulated Differentially J. Clin. Endocrinol. Metab., October 1, 2001; 86(10): 4991 - 5000. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. A. Johnson, F. W. Bazer, L. A. Jaeger, H. Ka, J. E. Garlow, C. Pfarrer, T. E. Spencer, and R. C. Burghardt Muc-1, Integrin, and Osteopontin Expression During the Implantation Cascade in Sheep Biol Reprod, September 1, 2001; 65(3): 820 - 828. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. S. Smyth, E. D. Reis, H. Vaananen, W. Zhang, and B. S. Coller Variable protection of {beta}3-integrin-deficient mice from thrombosis initiated by different mechanisms Blood, August 15, 2001; 98(4): 1055 - 1062. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
