Human sperm-egg recognition, adhesion and fusion are key steps in the whole reproductive process. Some abnormalities in human gamete interaction have been shown to be due to defects in the sperm, others attributed to defects in the zona pellucida (ZP) and the egg plasma membrane. This paper reviews the molecular basis and molecular mechanisms of human sperm-egg interaction. More and more advances in the studies of these aspects are shown to be of significant value to the diagnosis and treatment of infertility as well as to the development of assisted reproductive techniques.
Acrosome Reaction ; physiology ; Female ; Humans ; Infertility, Male ; physiopathology ; Male ; Sperm-Ovum Interactions ; physiology ; Zona Pellucida

No abstract available.
Sperm-Ovum Interactions* ; Spermatozoa*

No abstract available.
Sperm-Ovum Interactions* ; Spermatozoa*

OBJECTIVES: To evaluate the effects of sperm motility stimulants on the hyperactivation (HA), acrosomal reaction (AR) and sperm penetration assay (SPA) in fresh and frozen-thawed spermatozoa from fertile men. METHODS: We treated the semen samples obtained from 20 normospermic men (fresh semens from 10 and cryopreserved ones from 10) with pentoxiphylline (PF) and 2-deoxyadenosine (2-DXA) to evaluate the change of the patterns of motility using the computerized motility analyzer. The semen samples treated with motility stimulants were incubated in the medium with calcium ionophore A23187 for the examination of the proportion of acrosome lost spermatozoa. Finally we performed SPA in both groups for the evaluation of fertilizing capacity after stimulant treatments. RESULTS: In both fresh and cryopreserved semen samples, the addition of PF and 2-DXA significantly altered the patterns of motility (ALH, VCL, HA) known to have association with sperm quality without increasing the number of sperms with progressive motility and velocity. A23187 induced AR was also augmented by the treatment with PF and 2-DZA. Although the treatment with PF did not increase the mean rates of egg penetration significantly, in selected cases in the cryopreserved semen group, the improvement of the motility pattern was impressive. CONCLUSION: PF and 2-DXA can improve the quality of sperm function in both fresh and frozen-thawed semen from normal fertile men and may increase the sperm penetration rate of zona-free hamster eggs in selected samples of the frozen-thawed semen. The results suggest that PF and 2-DXA pretreatment can be used in the clinical practice for intrauterine insemination (IUI) program with frozen-thawed sperms as well as with samples from men with abnormal semen parameters. In addition, it may be a cost- effective therapy to try IUI combined with such a pretreatment for the couples planned to enter into the ART program.
Acrosome ; Acrosome Reaction ; Animals ; Calcimycin ; Calcium ; Cricetinae ; Eggs ; Family Characteristics ; Fertilization in Vitro* ; Humans ; Insemination ; Male ; Ovum ; Semen ; Sperm Motility* ; Sperm-Ovum Interactions ; Spermatozoa*

OBJECTIVE: This study was designed to investigate the interrelationship and clinical usefulness of sperm morphology by strict criteria (SM), acrosome reaction following ionophore challenge test (ARIC) and sperm penetration assay (SPA) using zona-free hamster ova as prognostic factors in in vitro fertilization. MATERIALS AND METHODS: Semen samples were provided by 83 patients undergoing IVF. We first evaluated the differences between normal fertilization group and poor fertilization group on three andrologic tests. Secondly, we analyzed the relationship between the three andrologic tests and in vitro fertilization on IVF settings. Finally, we evaluated the effectiveness of the three andrologic tests as the prognostic indicators for fertilizing ability. RESULTS: The fertilization rate of all men in the poor fertilization group was less than 30%; but there was no evidence that this poor fertilization was due to oocyte defects. The results of three andrologic tests were significatly higher in normal fertilization group. Fertilization rate (%) in vitro was highly correlated (p<0.001) with % normal sperm by SM, ARIC value (%), and SPA result. By using Receiver-Operator-Characteristic curve (ROC), we evaluated the effectiveness of these three tests. The sensitivity and specificity of SM, ARIC test and SPA in predicting fertilization potential in IVF setting were 76% and 75%, 84% and 90%, and 76% and 95%, respectively. CONCLUSION: Our data suggest that the three andrologic tests can be reliable tools as prognostic factors of sperm fertilizing ability. Among these test, ARIC test and SPA gave more accurate information on fertilizing capacity. ARIC test was shown to have a predictive value for fertilizing ability comparable to that of SPA that appears to be a simple and cost-effective addition to current andrology laboratory. Combined application of these three tests may give more information on predicting sperm fertilizing capacity.
Acrosome Reaction* ; Acrosome* ; Andrology ; Animals ; Cricetinae* ; Diagnosis* ; Fertilization ; Fertilization in Vitro* ; Humans ; Infertility, Male* ; Male ; Male* ; Oocytes ; Ovum* ; Semen ; Sensitivity and Specificity ; Sperm-Ovum Interactions* ; Spermatozoa*

OBJECTIVE: To determine the sperm-zona pellucida (ZP) binding and ZP-induced acrosome reaction in patients with unexplained infertility, and to discuss the relationship between ZP-induced acrosome reaction and fertilization rate. METHODS: We compared the fertilization rate and good embryo rate in patients with unexplained infertility after fertilization in 2 ways. Based on the causes of infertility, patients were divided into an unexplained infertility group (Group A) and a pure female tubal factor group (Group B). Oocytes which were obtained by super ovulation from 25 patients with unexplained infertility were randomly divided into 2 groups with conventional in vitro fertilization (IVF) (Group A1) and intracytoplasmic sperm injection (ICSI) fertilization (Group A2). The pure female tubal factor group (Group B) had conventional IVF. We conducted sperm-ZP binding and ZP-induced acrosome reaction experiments with 2 groups of men's sperms separately. We compared the number of sperm-egg binding and ZP-induced acrosome reaction rate and discussed the relationship between the ZP-induced acrosome reaction and fertilization rate, and also the fertilization rate, good embryo rate and pregnancy rate in patients with unexplained infertility after fertilization in 2 ways. RESULTS: The average number of sperm-egg binding (78.29 ± 16.31) and the ZP-induced acrosome reaction rate (55.87 ± 27.69) % in Group A were lower than those of Group B [94.63 ± 6.72, (82.53 ± 17.99)%]. The difference between the average number of sperm-egg binding and the ZP-induced acrosome reaction was significant (P <0.01). The fertilization rate of Group A1 was significantly lower than that of Group B and Group A2 (P <0.01). But there was no significant difference in the good embryo rate among the 3 groups. There was no significant difference between Group A2 and B in fertilization rate and good embryo rate (P <0.05). There was no significant difference in pregnancy rate between Group A and B (P <0.05). Fertilization rate and the rate of acrosome reaction had marked positive correlation with statistical significance (r =0.932, P <0.01). CONCLUSION ZP binding and ZP-induced acrosome reaction are very important experiments in sperm function test for patients with unexplained infertility. It can not only effectively avoid no embryo transferring due to complete failure of fertilization but also get a desirable outcome of pregnancy using half-ICSI fertilization in patients with unexplained infertility.
Acrosome Reaction ; Embryo Transfer ; Female ; Fertilization in Vitro ; Humans ; Infertility ; etiology ; therapy ; Male ; Oocytes ; physiology ; Ovulation Induction ; Sperm Injections, Intracytoplasmic ; Sperm-Ovum Interactions ; physiology ; Treatment Outcome ; Zona Pellucida ; physiology

OBJECTIVE: Lectins are cell-agglutinating and sugar specific proteins or glycoproteins of non-immune origin that precipitate glycoconjugates having saccharides of appropriate complementarity. Because of these properties, plant lectins have been used to help characterize the carbohydrate moieties of glycoproteins in the zona pellucida (ZP) of several mammalian species including pigs. Treatment of oocytes with various lectins blocks sperm binding to the ZP in various mammalian species. This study was undertaken to examine the distribution of sugar residues in the ZP of pig oocytes matured in vitro and the ability of spermatozoa to bind to ZP and in vitro penetration in oocytes treated with fluorescein isothiocyanate (FITC)-labelled lectins. MATERIALS AND METHODS: The lectins of Banderiaea simplicifolia (BS-II, bind to beta-D-Nacetylglucosamine), Canavalin ensiformis (Con A, bind to alpha-D-Mannose), Lens culinaris (LCA, bind to alpha-D-Mannose), Ricinus communis (RCA-I, bind to beta-D-Galactose) and Ulex europaeus (UEA-I, bind to alpha-L-Fucose) were examined for spermatozoa penetration, binding capacity to ZP and distribution of lectins. RESULTS: The penetration rates were significantry (p<0.05) higher in control oocytes (63%) than those treated with all lectins, but penetration rates (40~49%) were simililar in group treated with lectins. The incidence of monospermy was similar in oocytes untreated and UEA-I, but it was higher in oocytes treated with BS-II, Con A, RCA-I and LCA. The porcine oocytes cultured for 48 h in TC-199 medium were freed from cumulus cells and treated for 30 min with fluorescein isothiocyanate-labelled lectins. When examined under fluorescein illumination, higher (p<0.001) proportions of oocytes showed fluorescein of zona pellucida after treatment with Con A (93%), LCA (93%) and RCA-I (100%) than BS-II (37%) and UEA-I (50%). All of the oocytes treated with RCA-I exhibited strong fluorescein in the outer region of the zona pellucida while those treated with LCA exhibited strong fluorescein throughout the zona pellucida. BS-II bounded mainly to the outer region and UEA-I bounded mainly to the inner region of the zona pellucida, with either strong or weak fluorescein. At 120 min after insemination in vitro, fewer spermatozoa were bound to the zona pellucida of the oocytes treated with BS-II, Con-A and RCA-I. Of the lectins, Con A most inhibited sperm binding. CONCLUSIONS: These results suggest that beta-D-Galactose residues in the porcine zona pellucida may act as primary sperm receptors and inducers of the sperm acrosome reaction and these sugar residues may be involved in the block to polyspermy.
Acrosome Reaction ; Cumulus Cells ; Fluorescein ; Glycoconjugates ; Glycoproteins ; Herpes Zoster* ; Incidence ; Insemination ; Lectins* ; Lens Plant ; Lighting ; Oocytes ; Plant Lectins ; Ricinus ; Sperm-Ovum Interactions ; Spermatozoa ; Swine ; Ulex ; Zona Pellucida*

No abstract available.
Chromatin* ; Humans* ; Population Characteristics* ; Sperm-Ovum Interactions* ; Spermatozoa*

Sperm membrane fluidity is one of the causes of male infertility, and it is thought to be related with temperature, reactive oxygen species, oxygen free radicals, anti-sperm antibodies, stilbestrol, and fenvalerate. A deeper insight into the influencing factors of sperm membrane fluidity is of vital importance for in vitro sperm preservation, revival of frozen-thawed sperm, in vitro fertilization and management of male infertility.
Humans ; Infertility, Male ; Male ; Membrane Fluidity ; Semen Preservation ; Sperm Motility ; Sperm-Ovum Interactions ; Spermatozoa ; physiology

To establish sperm penetrating assay (SPA) with using cryopreserved hamster oocyte, we performed the stepwise SPA with 1) fresh hamster oocyte and hamster sperm, 2) cryopreserved hamster oocyte and hamster sperm, 3) fresh hamster oocyte and human sperm, and 4) cryopreserved hamster oocyte and human sperm, in 4 cases of male hamster and 12 cases of fertile human. In SPA of hamster sperm with fresh hamster oocyte, the oocyte penetration rate (PR) were 100+0%, and the penetration index(mean penetration per oocyte, PI) was 22.4 +/- 1.8. In SPA of hamster sperm with cryopreserved hamster oocyte, the PR were 100 +/- 0%, and the Pl was 14.1 +/- 2.9 (p<0.01). When the oocytes were examined at 1, 2, 3, and 6 hour post insemination, hamster sperm penetration was 1 hour slower in cryopreserved oocytes than in fresh ones. In SPA of human sperm with fresh hamster oocyte, the PR was 79.5 +/- 10%, and the Pl was 2.78 +/- 2.6. In SPA of hamster sperm with cryopreserved hamster oocyte, the PR was 73.9+/- 16%, and the PI was 2.82 +/- 2.7. There`s no significant difference in SPA using human sperm. These results suggest that them may be some functional damages on cryopreserved oocyte, because Pl of fresh oocytes is higher than that of cryopreserved oocytes. However in sperm of human, it dose not make significant difference in Pl between fresh and cryopreserved oocytes. The SPA using cryopreserved hamster oocyte would appear to have wide application of the evaluation of infertility, the assessment of the treatment of infertility and the experiment in infertility field.
Animals ; Cricetinae* ; Humans ; Infertility ; Insemination ; Male ; Oocytes* ; Sperm-Ovum Interactions* ; Spermatozoa*