The effects of prolactin on human sperm capacitation and acrosome reaction

OBJECTIVE: To study the effects of human prolactin (PRL) on human sperm capacitation and acrosome reaction. DESIGN: Acrosome reactions were induced by the addition of follicular fluid (FF) and progesterone (P). Experiments were performed to determine time and dose-dependent effects of PRL on sperm capacitation, potentiation of the acrosome reaction, decapacitating effects, and potential for PRL to induce an acrosome reaction. RESULTS: An average of 31.5% of spermatozoa underwent acrosome reaction with addition of FF and P. No time- or dose-dependent PRL effects on sperm capacitation or acrosome reaction were found (P greater than 0.05). CONCLUSION: Prolactin does not play an important role in human sperm capacitation or acrosome reaction.     

An antisperm monoclonal antibody inhibits sperm fusion with zona-free hamster eggs but not homologous eggs

The zona-free hamster egg penetration assay (HEPA) was evaluated as a test for identifying fertilization-blocking antibodies. A monoclonal antibody, AH-20, that binds to the surface of guinea pig sperm was used to test antibody inhibition of sperm-egg fusion. AH-20 strongly inhibited guinea pig sperm fusion with zona-free hamster eggs but had no effect on guinea pig sperm fusion with zona-free guinea pig eggs. No inhibition by AH-20 was found in the homologous fusion assay over a wide range of sperm concentration, fertilization rate, and fertilization index. The results suggest that although guinea pig sperm can fuse with both hamster and guinea pig eggs, some aspect of the fusion mechanism is different in the two cases. The findings also indicate that HEPA, which is frequently used to assess the fertility potential of human sperm, can identify as blockers of sperm-egg fusion antibodies that have no effect on homologous sperm-egg fusion.     

Inconsistent reactivity of an anti-sperm monoclonal antibody and its relationship to sperm capacitation

An anti-sperm monoclonal antibody was developed from female C57BL/6 mice immunized with epididymal sperm from a syngeneic male mouse. Immunofluorescence staining revealed that the antibody did not react to fresh epididymal sperm but attached to the capacitated sperm found in the peri-vitelline spaces of the ova. When the antibody was applied to sperm incubated in vitro, variously stained sperm were observed. It was presumed that the antigenic site detected by the antibody was hidden in the fresh epididymal sperm and was spread from the acrosomal cap region to the entire head during the capacitation process.     

Interactions between zona pellucida glycoproteins and sperm proacrosin/acrosin during fertilization.

Fertilization is one of the most specific and carefully regulated cell-cell interactions in the animal body and is determined to a large extent by compatibility between ligand and receptor molecules on the surface of each gamete. On the zona pellucida (ZP), sperm receptor activity is associated with glycoproteins ZP3 (primary receptor for acrosome-intact sperm) and ZP2 (secondary receptor for acrosome-reacted sperm) but their complementary binding proteins on sperm are less well defined. In this communication we review the evidence for proacrosin as a secondary ZP binding protein. Proacrosin/acrosin binds non-enzymically to ZP glycoproteins. Binding is a strong ionic interaction between polysulphate groups on ZP glycoproteins (probably on their carbohydrate moieties) and basic residues on the surface of proacrosin. The stereochemistry of the reactants is crucial and determines to a large extent the affinity of binding. Site-directed mutagenesis and a 3D-structural analysis of boar and ram acrosin have identified 2 clusters of basic residues potentially involved in binding. A polysulphonated anticancer drug, suramin, has been shown to bind strongly to proacrosin/acrosin and to inhibit sperm-egg binding in vitro. In the mouse model, 125I-ZP2 and 3H-suramin bind approximately 65% less effectively to acrosin 'null' sperm than to wild-type sperm. Neither ZP2 nor suramin bind to acrosome intact sperm and can, therefore, only exert their effects after exposure of the acrosomal contents. Overall, this combination of biochemical, genetic and functional data supports the hypothesis that proacrosin is a multifunctional protein with a significant role in retaining acrosome-reacted sperm on the ZP surface long enough to enable ZP penetration to begin.     

The biological significance of phospholipase C beta 1 gene mutation in mouse sperm in the acrosome reaction, fertilization, and embryo development

Purpose: We carried out this study to evaluate the biological significance of phospholipase C 1 gene mutation in mouse sperm in the acrosome reaction, fertilization, and embryo development.Methods: Study subjects were divided into two groups according to the sperm [intact phospholipase C (PLC) 1 and PLC 1^–/– C57BL/6J × CBA F₁ mouse sperm] used. The positive acrosome reaction rate labeled with fluorescein isothiocyanate–Pisum sativum agglutinin, the fertilization rate, and the rate of embryos developed to the stage of morula or blastocyst in the two groups were compared.Results: The mouse sperm null for the PLC 1 gene showed a lower acrosome reaction rate than control sperm (69.2 vs 50.9%, P < 0.05). And the fertilization rate and the rate of embryos developed to the stage of morula or blastocyst were also lower in the group using PLC 1^–/– mouse sperm compared to the intact group (P < 0.05; 73.5 vs 51.8% and 15.7 vs 4.3%, respectively).Conclusions: Mutation of the PLC 1 gene in the mouse sperm reduces the acrosome reaction rate, fertilization rate, and embryo development rate, which may be the etiologic factors responsible for the low reproductive rate of PLC 1^–/– mouse.     

Relationship between zona pellucida-induced acrosome reaction,sperm morphology,sperm-zona pellucida binding,and in vitro fertilization

OBJECTIVE: To evaluate the possible relationships between sperm morphology, acrosome responsiveness to solubilized human zona pellucida, and sperm-zona binding potential among [1] consecutive andrology referrals and [2] randomly selected in vitro fertilization (IVF) cases. DESIGN: Prospective analytical study. SETTING: Academic training hospital.Randomly selected couples consulting for infertility. INTERVENTION(S): Acrosome reaction response to solubilized human zona pellucida was recorded. MAIN OUTCOME MEASURE(S): We determined the difference in the percentage of sperm that acrosome reacted after exposure to solubilized zona pellucida and spontaneous acrosome reaction. The results were expressed as percentage zona induced acrosome reaction (ZIAR). RESULT(S): Data were analyzed using correlation coefficients (r) and receiver operator characteristics (ROC curve analyses). The ROC curve analyses indicated ZIAR to be a sensitive indicator for fertilization failure during IVF therapy, with sensitivity and specificity of 81% and 75%, respectively. For andrology referrals, a positive and statistically significant correlation existed between ZIAR data and sperm morphology (r = 0.65) and sperm-zona binding (r = 0.57). CONCLUSION(S): ZIAR results provide further information regarding dysfunctional sperm and can be used as an additional diagnostic test. Our results predicted fertilization failure during IVF treatment.     

The kinetics of the acrosome reaction of human spermatozoa and its correlation with in vitro fertilization.

OBJECTIVE: To study the reaction pattern of acrosome reaction in human semen and correlate it to the results of in vitro fertilization (IVF). DESIGN: The percentage of acrosome-reacted spermatozoa of 41 IVF semen samples was determined after 0, 2, 4, and 24 hours of incubation in human tubal fluid medium supplemented with 10% human pool serum. SETTING: St. Radboud Hospital, Catholic University of Nijmegen, The Netherlands. PATIENTS: Forty-one IVF couples. INTERVENTIONS: None. MAIN OUTCOME MEASURE: Acrosome reaction was determined using fluorescein isothiocyanate conjugated concanavalin A lectin. To avoid false-positive signals from dead spermatozoa, the sperm viability was determined. RESULTS: Three kinetic patterns of acrosome reaction could be distinguished: (1) normal reacting pattern (percentage of acrosome-reacted spermatozoa less than 10% at 2 hours and greater than 5% at 4 hours; 75% fertilization in IVF); (2) a quickly reacting pattern (percentage of acrosome-reacted spermatozoa greater than 10% at 2 hours; 22% fertilization in IVF); and (3) a nonreacting pattern (percentage of acrosome-reacted spermatozoa less than 5% at all time intervals studied; 15% fertilization in IVF). CONCLUSIONS: The timing of acrosome reaction and the percentage of acrosome-reacted spermatozoa are very important parameters in IVF.     

The effects of calmodulin and it's antagonist, W-7, on the acrosome reaction and fertilization of human spermatozoa

The acrosome reaction of mammalian spermatozoa has been shown to be dependent upon an influx of Ca2+ following capacitation. Recently it was shown that calmodulin which activates various enzymatic activities in a calcium-dependent manner is contained in the acrosomal portion of sperm obtained from diverse species including human. Therefore calmodulin appears to be the primary target for Ca2+-dependent regulatory process involved in the acrosome reaction. This report examines the effects of calmodulin and it's antagonist, W-7, on the acrosome reaction in human spermatozoa and the fertilization with zona free hamster eggs. The results are as follows: 1) In the experiment on fertilization in mBWW medium with 30nM of calmodulin, there was no significant difference between the calmodulin and the control. (2) In fertilization in mBWW medium with 2.5 to 25 microM of W-7, there were no significant changes in the fertilization rate, but there was a significant decrease in the fertilization rate when the concentration of W-7 was elevated up to 50 microM. (3) When fertilization in mBWW was performed using spermatozoa pretreated with W-7, the fertilization rates were more markedly and promptly elevated with insemination times than the control. (4) When the eggs and spermatozoa were pretreated with W-7 before insemination and then placed in mBWW medium, the fertilization rate was markedly decreased. (5) Triple stain method and transmission electron microscopy showed that a large proportion of spermatozoa had undergone the acrosome reaction in mBWW medium containing W-7 with normal manner. From the results given above, it appears that calmodulin plays an important role in the acrosome reaction and fertilization in human spermatozoa.     

A monoclonal antibody,EC-1, derived from a syngeneically multiparous mouse alters in vitro fertilization and development

A monoclonal antibody designated ‘EC-1’ was derived from a fusion of myeloma cells with lymphoid tissue from a syngeneically multiparous, but otherwise unimmunized, mouse and was selected by screening for reactivity with teratocarcinoma cells. The IgM antibody binds to the cell surface of ova, zygotes, and 2-cell embryos. Binding is not detected on the 4- or 8-cell embryo but reappears on the morula and blastocyst. EC-1 binds to the trophoblast but not to the inner cell mass of in vitro attached blastocysts and the ectoplacental cone of the peri-implantation embryo. In adult tissues, EC-1 binds to the follicular cells of the ovary, the lining epithelium of the pregnant uterus, the interstitial region of the testes and to epidydimal but not testicular sperm. In nongonadal tissues EC-1 binds to an epitope located in some, but not all, regions of connectives tissues associated with basement membrane. The antigen detected by EC-1, as expressed on teratocarcinoma-derived cell line PYS-2, is a large glycoprotein which is sensitive to reduction. EC-1 inhibits in vitro fertilization and partially inhibits in vitro development of in vitro fertilized ova. The possible implications of EC-1 binding and activity are discussed.     

Round cells and sperm fertilizing capacity: the presence of immature germ cells but not seminal leukocytes are associated with reduced success of in vitro fertilization.

Fifty semen samples produced for IVF by patients diagnosed as having unexplained infertility were screened for leukocytes, leukocyte subsets, and immature germ cells using a mAB-based staining procedure. Nonfertilizing ejaculates were found to contain significantly larger numbers of immature germ cells, although no significant differences in leukocyte content were observed between groups. Neither sperm density or progressive motility were significantly different between fertilizing and nonfertilizing groups. We conclude that seminal leukocytes have little if any influence on the fertilizing capacity of the spermatozoa in patients undergoing IVF for unexplained infertility, but the presence of large numbers of germinal elements is associated with reduced fertilizing capacity and may be indicative of an immature sperm population.     

WBP2NL/PAWP mRNA and protein expression in sperm cells are not related to semen parameters,fertilization rate,or reproductive outcome

Purpose

WBP2NL/PAWP, a protein found in the post-acrosomal region of mammalian spermatozoa, has been proposed as a sperm-borne oocyte-activating factor (SOAF) contributing to Ca²⁺ release within the oocyte and subsequent fertilization and embryo development. However, its relevance as either a diagnostic or a prognostic marker of fertilization failure has been questioned in the recent literature. We analyzed WBP2NL/PAWP gene and protein expression level and localization in patients without previous intracytoplasmic sperm injection (ICSI) cycles in order to assess its association with both sperm characteristics and ability to fertilize.

Methods

Raw frozen-thawed semen samples from 33 couples referred for oocyte donation were included in the study during 2015. Relative protein expression versus α-tubulin (western blot, WB), proportion of post-acrosomal WBP2NL/PAWP-positive spermatozoa over the total number of sperm cells (immunofluorescence), and WBP2NL/PAWP gene expression (RT-qPCR) were analyzed and correlated with semen analysis parameters (number, motility, and morphology) and with reproductive outcomes.

Results

WBP2NL/PAWP protein was expressed in all samples with high variability: relative protein expression (1.77 ± 0.8, range [0.4–3.7]), proportion of positive cells (49.6% ± 16.1, range [22–89]), and relative gene expression (7.3 ± 8.2). No significant correlation (R ² < 0.1) was found between gene and protein expression, neither between WBP2NL/PAWP gene or protein expression, and fertilization rate or other reproductive outcomes (i.e., pregnancy). In contrast, we found significant correlation between sperm morphology and WBP2NL/PAWP semiquantitative analysis in WB (r = ?0.42, p < 0.05) and for sperm motility and WBP2NL/PAWP expression in IF (r = 0.52, p < 0.05).

Conclusion

Taken into account that WBP2NL/PAWP gene and protein levels and distribution did not correlate with fertilization rates, this study questions the interest of WBP2NL/PAWP protein and gene expression analysis in sperm cells as a prognostic factor for the outcome of ICSI cycles. Larger studies focusing on WBP2NL/PAWP protein and gene expression are needed in order to evaluate the role of WBP2NL/PAWP as a prognostic factor for ART.

     

The production and characterization of monoclonal antibody, 1C5, reactive with cervical adenocarcinoma of the uterus

A new monoclonal antibody, 1C5, was produced by fusion of spleen cells obtained from mice immunized with CAC-1, a human cell line of cervical adenocarcinoma of the uterus, and NS-1 myeloma cell. The objectives of this study were to obtain moAb that can be used for routine histology and cytology, and to examine the histogenesis of cervical adenocarcinoma. 1. 1C5 reacted with 88% of cervical adenocarcinoma of the uterus, but did not react with cervical squamous cell carcinoma of the uterus and other squamous cell carcinoma. However, 1C5 reacted with some adenocarcinomas, such as endometrial carcinoma of the uterus and ovarial carcinoma. 2. The staining pattern by 1C5 was different, in cervical adenocarcinoma from that in endometrial carcinoma of the uterus, and also different in the endocervical type from that in the endometrioid type of cervical adenocarcinoma. Therefore, 1C5 is useful in distinguishing between two types of adenocarcinoma of the uterus. 3. 1C5 did not react with normal squamous cells or normal columnar cells of the uterine cervix, or with normal endometrial cells of the uterus. However, the columnar cells in a limited area of the squamocolumnar junction were strongly stained with 1C5. 4. 1C5 reacted with ethanol-fixed, and routine formalin-fixed and paraffin-embedded tissue. Thus, 1C5 may be used for clinical diagnosis. 5. 1C5 was found to be IgG1. 6. The molecular weight of the 1C5-defined antigen was 26,000 daltons, and the epitope of the 1C5-defined antigen was carbohydrate moiety. 7. We examined the histogenesis of cervical adenocarcinoma of the uterus by utilizing the reactivity of 1C5.(ABSTRACT TRUNCATED AT 250 WORDS)     

Presence of expression products of c-erbB-1 and c-erbB-2/HER2 genes on mammalian sperm cell, and effects of their regulation on fertilization.

The present study was conducted to investigate the presence of expression products of c-erbB-1 and c-erbB-2/HER2 genes on mammalian sperm cell, and study the effects of their antibodies on fertilization. The mature sperm cells from various mammalian species (human, mouse, rabbit and rat) were found to have EGF-receptors but not the p185HER2 molecules by indirect immunofluorescence technique (IFT) and Western blot procedure. Though the EGF-receptors present on sperm cells were functionally active and responded to ligand binding, their activation by EGF or blocking by antibodies did not affect the sperm cells in acquiring their fertilization potential. These results indicate that the products of c-erbB-1 and c-erbB-2/HER2 genes, though they have been shown to have tyrosine kinase enzyme activity, do not seem to play a major role in the development of the fertilizing capacity of sperm cells.     

The different dosages of estrogen affect endometrial fibrosis and receptivity,but not SDF-1/CXCR4 axis in the treatment of intrauterine adhesions

Objective: The study was to evaluate whether fibrotic markers, endometrial receptivity markers and SDF-1/CXCR4 had been changed in the treatment of intrauterine adhesions (IUAs) by different dosages of estrogen.

Study design: A total of 39 patients with IUAs were treated with EV 4?mg or 9?mg randomly post-surgery. TGF-β1/MMP-9, VEGF/αvβ3 and SDF-1/CXCR4 were detected in endometrial tissue before and after treatment by real-time PCR and Western blot.

Results: TGF-β1 and MMP-9 expression significantly decreased after treatment for 3?months than before (p?p?p?p?p?>?.05). SDF-1 presented an upward tendency at early phase, and it came back to the level of pre-surgery. But there were no significant difference between treatment with 4?mg and 9?mg in the rate of menstrual restoration and pregnancy follow-up 3?months after the treatment.

Conclusions: Endometrium fibrosis may be inhibited and endometrium receptivity may be improved by estrogen with moderate dosage therapy. Compared to the large one, it seems to be advantageous.