Oviduct Epithelial Cell Co-culture Research Articles

Development of buffalo embryo derived from ICSI: effects of various somatic-cell co-culture

Context Somatic-cell co-culture of intracytoplasmic sperm injection (ICSI) buffalo embryos has not been reported earlier. Aim This study aimed to determine the effects of buffalo oviductal epithelial-cell, granulosa-cell, and cumulus-cell co-culture on in vitro culture of early embryo development as ICSI and post-activation. Methods Selected oocyte–cumulus complexes were cultured for 19–20 h in 50-μL drop of tissue culture medium (TCM199 + 10% buffalo follicular fluid, hCG 50 IU/mL, 0.02% arbitrary units (AU)/mL follicle-stimulating hormone and 1 μg/mL estradiol-17βE2). Oocytes reaching Metaphase II were subjected to ICSI with immobilised spermatozoa. All ICSI oocytes were activated with calcium ionophore for 5 min, followed by cycloheximide for 5 h. The embryos at 6–8-cell stages were co-cultured. Key results The morula, blastocyst, and hatched blastocyst rates when co-cultured with oviductal epithelial cells were 68.18%, 48.18%, and 30.00% respectively. The morula, blastocyst, and hatched blastocyst rates when co-cultured with cumulus cells were 51.49%, 34.33%, and 16.42% respectively. The morula, blastocyst, and hatched blastocyst rates when co-cultured with granulosa cells were 52.14%, 32.48%, and 13.68% respectively. Conclusions In vitro maturation buffalo oocytes can be fertilised in vitro with ICSI and co-cultured with different types of cells. Oviductal epithelial cell co-culture was shown to be superior in supporting in vitro embryo development in this study. Implications The oviductal epithelial cells are easy to prepare and may be used for co-culture to increase the efficiency of in vitro production of buffalo embryos.

Peroxiredoxin 6 Plays Essential Role in Mediating Fertilization and Early Embryonic Development in Rabbit Oviduct.

The oviduct is a site for early reproductive events including gamete maturation, fertilization, and early embryo development. Secretory cells lining the oviduct lumen synthesize and secrete proteins that interact with gametes and developing embryos. Although previous studies have identified some of the secretory proteins in the oviduct, however, knowledge and their precise specific functions in the oviduct are poorly understood. In this study, by using proteomic approach, we identified a secretory protein, Peroxiredoxin 6 (PRDX6), and evaluated its role in mediating early pregnancy events, fertilization, and embryo development in rabbit oviduct. The expression of PRDX6 was significantly higher in ampulla and isthmus sections of the oviduct in mated animal groups compared to non-mated controls. Furthermore, significant reduction in number of embryos recovered from PRDX6 siRNA-transfected oviductal horn was observed compared to the control contralateral horn. Moreover, in animals receiving PRDX6 siRNA in their oviductal horn, the number of implanted blastocysts was significantly less in the uterus as observed on day 9 post-coital (p.c.). Further, during embryo-rabbit oviduct epithelial cell (ROEC) co-culture, siRNA-mediated PRDX6 silencing attenuated the early embryonic development. Mechanistically, increased levels of ROS and expression of oxidative stress- and inflammation-related proteins were found in PRDX6 siRNA-treated ROEC cells as compared to control cells, implicating that ablation of PRDX6 in the oviduct creates a stress-induced micro-environment detrimental to early embryonic development in oviduct. Taken together, our data suggest that PRDX6 maintains an optimal micro-environment conducive to successful embryo development and can be considered as a candidate to evaluate its therapeutic potential in IVF strategies.

Frozen-thawed ampullary cell monolayer improves bovine embryo in vitro development and quality.

The aim of this study was to evaluate the effects of different timing for frozen-thawed bovine ampullary epithelial cell (BAEC) and bovine oviductal epithelial cell (BOEC) co-culture on the development and quality of bovine embryos produced in vitro. Embryo development was assessed by day 8 blastocyst yield, whereas embryo quality was determined using blastocyst differential cell count, cryotolerance and the expression of selected genes related to embryo quality. The results showed that the presence of BAECs during the last 6 h of in vitro maturation (IVM) increased blastocyst yield and survival of the vitrified-warmed blastocysts. In addition, embryos produced in the presence of BAECs during the last 6 h of IVM or in the presence of BOECs during the first 4 days of in vitro culture (IVC) showed a greater number of trophectoderm cells and a greater inner cell mass. In terms of gene expression, IFN-T was downregulated and PLAC8, AQP3 and ATP1A1 were upregulated in the presence of the BAECs during the last 6 h of the IVM and/or in the presence of BOECs during the first 4 days of IVC. In conclusion, co-culturing bovine oocytes with a frozen-thawed ampullary cell monolayer during the last 6 h of maturation increased blastocyst yield and quality.

Supplementation of 17β-estradiol and progesterone in the co-culture medium of bovine oviductal epithelial cells and ovine spermatozoa reduces the sperm kinematics and capacitation

This study investigated the effect that bovine oviductal epithelial cell (BOEC) and ovine spermatozoa co-culture exposed to different hormonal environments had on ram sperm function over the course of a 24-h incubation period. Ram cooled-stored spermatozoa were selected by swim-up and then co-cultured separately for 24 h at 38.5 °C under 5% CO2 with either: (1) Fert-TALP medium (positive control [POSControl]), (2) Fert-TALP medium supplemented with 17β-estradiol (E2) and progesterone (P4) at concentrations similar to follicular phase (Follicular NEGControl), (3) Fert-TALP medium supplemented with E2 and P4 concentrations similar to luteal phase (Luteal NEGControl), (4) BOEC cultured in the same medium as that of the Follicular NEGControl group (Follicular BOEC group), or (5) BOEC cultured in the same medium as that of the Luteal NEGControl group (Luteal BOEC group). The sperm kinematics, capacitation status, and plasma membrane (PM) integrity were evaluated at different intervals. Sperm PM integrity was not affected (P ˃ 0.05) by BOEC co-culture, regardless of the phase of the estrous cycle. After 4 h of incubation, the Luteal BOEC group presented lower (P < 0.05) progressive motility and total motility than the Luteal NEGControl group while the Follicular BOEC group showed lower (P < 0.05) velocimetric parameters and progressive motility than the Follicular NEGControl group. Throughout the incubation period, both BOEC co-culture groups showed a decrease (P < 0.05) in their capacitation rate in comparison to the POSControl group. Conversely, the Luteal BOEC group presented a higher (P < 0.05) non-capacitated rate than both the POSControl and Luteal NEGControl groups. In conclusion, BOEC co-culture with ovine spermatozoa at either the follicular or luteal phase decreases sperm kinematics and delays sperm capacitation.

Enhanced in vitro maturation of canine oocytes by oviduct epithelial cell co-culture

Canine-assisted reproductive techniques have been successful for several years; however, the lack of an oocyte in vitro maturation system has limited their application. The aim of this study was to evaluate the effect of canine oviduct epithelial cells (cOECs) on canine oocyte maturation in vitro. Specifically, the method used for isolation of cOECs did not affect the expression of epithelial markers, E-cadherin and cytokeratin, on fresh, cultured and cryopreserved cells. Moreover, BrdU analysis showed that cOECs cultured in Medium 171 supplemented with mammary epithelial growth supplement were more proliferative than counterparts in advanced Dulbecco's modified Eagle medium or Medium 199. Maturation rate of canine oocytes collected from bitches at diestrus was significantly increased when oocytes were co-cultured with either fresh, cultured or frozen/thawed cOECs (13.23 ± 1.15%, 10.38 ± 4.89%, or 10.54 ± 2.96%, respectively) than that of control oocytes cultured without cOECs (2.48 ± 2.16%, p < 0.05). Additionally, the number of oocytes collected from bitches at estrus the reached metaphase II was increased ∼4 fold in co-culture with fresh, cultured, or frozen/thawed cOECs (47.2 ± 3.82%, 45.4 ± 7.34%, and 46.9 ± 1.51%, respectively) as compared with oocytes cultured without cOECs (11.9 ± 3.18%, p < 0.05). Nuclear maturation was further confirmed by assessing the formation of normal metaphase-II spindles, whereas cytoplasmic maturation was confirmed by inducing parthenogenetic oocyte activation. Embryonic development to the 8-cell stage was similar between in vivo and in vitro matured oocytes. These results suggested that co-culturing immature canine oocytes with cOECs facilitated canine oocyte maturation and early stages of embryonic development.

The Motility of Bovine Sperm and Fertilization Rate of Oocytes during In-Vitro Fertilization following Oviduct Epithelial Cell Co-culture

The Motility of Bovine Sperm and Fertilization Rate of Oocytes during In-Vitro Fertilization following Oviduct Epithelial Cell Co-culture

Melatonin Attenuates Nitric Oxide Induced Oxidative Stress on Viability and Gene Expression in Bovine Oviduct Epithelial Cells, and Subsequently Increases Development of Bovine IVM/IVF Embryos

The objective of the present study was to elucidate the fundamental mechanism of bovine oviduct epithelial cell (BOEC) co-culture on developmental capacity of bovine IVM/IVF embryos and to determine whether or not melatonin acts as an antioxidant in BOEC culture and subsequent embryo development. These studies examined the effects of melatonin against NO-induced oxidative stress on cell viability, lipid peroxidation (LPO) and the expression of antioxidant genes (CuZnSOD, MnSOD and Catalase) or apoptosis genes (Bcl-2, Caspase-3 and Bax) during BOECs culture. We also evaluated the developmental rates of bovine IVM/IVF embryos with BOEC co-culture, which were pre-treated with melatonin () in the presence or absence of sodium nitroprusside (SNP, ) for 24 h. Cell viability in BOECs treated with SNP (50-) decreased while melatonin addition (1-) increased viability in a dose-dependent manner. Cell viability in melatonin plus SNP () gradually recovered according to increasing melatonin addition (1-). The LPO products were measured by thiobarbituric acid (TBA) reaction for malondialdehyde (MDA). Addition of melatonin in BOEC culture indicated a dose-dependent decrease of MDA, and in the SNP group among BOECs treated with SNP or melatonin plus SNP groups MDA was significantly increased compared with SNP plus melatonin groups (p melatonin group. These results suggest that melatonin has an anti-oxidative effect against NO-induced oxidative stress on cell viability of BOECs and on the developmental competence of bovine IVM/IVF embryo co-culture with BOEC.

Antioxidative Effects of Astaxanthin against Nitric Oxide‐Induced Oxidative Stress on Cell Viability and Gene Expression in Bovine Oviduct Epithelial Cell and the Developmental Competence of Bovine IVM/IVF Embryos

The aim of the present study was to elucidate the fundamental mechanism of bovine oviduct epithelial cell (BOEC) co-culture on developmental capacity of bovine in vitro oocyte maturation/in vitro fertilization (IVM/IVF) embryos. We examined the effects of astaxanthin against nitric oxide-induced oxidative stress on cell viability by MTT assay, lipid peroxidation (LPO) by using thiobarbituric acid (TBA) reaction for malondialdehyde (MDA) and the expression of antioxidant genes (CuZnSOD, MnSOD and Catalase) or apoptosis genes (Bcl-2, Caspase-3 and Bax) by RT-PCR in BOEC. We also evaluated the developmental rates of bovine IVM/IVF embryos co-cultured with BOEC pre-treated with astaxanthin (500 μM) in the presence or absence of sodium nitroprusside (SNP, 1000 μM) for 24 h. Cell viability in BOEC treated with SNP (50-2000 μM) lowered, while astaxanthin addition (50-500 μM) increased it in a dose-dependent manner. Cell viability in astaxanthin plus SNP (1000 μM) gradually recovered according to the increase in astaxanthin additions (100-500 mM). The LPO in astaxanthin group (50-500 μM) gradually decreased in a dose dependent manner and among SNP or astaxanthin plus SNP group, SNP alone and astaxanthin (50 μM) plus SNP shown a significant increase than other groups (p < 0.05). Expression of apoptosis or antioxidant genes was detected by RT-PCR. Bcl-2 and antioxidant genes were detected in astaxanthin or astaxanthin plus SNP group, and Caspase-3 and Bax genes were only found in SNP group. When bovine IVM/IVF embryos were cultured for 6-7 days under co-culture system such as BOEC treated with astaxanthin in the presence or absence of SNP, the developmental ability to blastocysts in 500 μM astaxanthin group was the highest of all groups. These results suggest that astaxanthin has a antioxidative effect on cell viability and LPO of BOEC, and development of bovine IVM/IVF embryos due to the induction of antioxidant genes and suppression of apoptosis genes.

Direct contact between boar spermatozoa and porcine oviductal epithelial cell (OEC) cultures is needed for optimal sperm survival in vitro

Oviductal epithelial cell (OEC) co-culture prolongs sperm viability and motility in vitro in a number of species including humans and horses. This study has sought to determine the effects of homologous OEC co-culture on boar sperm function. To determine whether the effects on spermatozoa were specifically caused by co-culture with or by OEC secretions, or by both factors together, a number of co-culture and cell-conditioned medium (CM) experiments were conducted. Firstly, Percoll-washed spermatozoa were co-cultured with OECs and pig kidney epithelial (LLC-PK1) cells, and in medium without cells. Secondly, Percoll-washed spermatozoa were incubated with CM derived from both OECs and LLC-PK1 cells and in unconditioned medium. A number of sperm function parameters were assessed after 5, 30, 60, 90, 120, and 180 min, and 24 h of co-culturing or incubation with CM. Of all the sperm function parameters investigated, the percentage (%) viability data yielded the most interesting results. OECs (mean ± S.E.M.; 31.2 ± 1.10) were better than LLC-PK1 cells (24.3 ± 0.93) at prolonging the viability of unbound spermatozoa after 24 h of co-culturing ( P < 0.05). Also after 24 h, the viability of spermatozoa bound to the OECs (77.6 ± 1.83) was significantly higher than in the case of the LLC-PK1 cells (53.5 ± 1.43; P < 0.001). Other sperm function parameters, e.g., capacitation and motility, were also influenced by OEC co-culturing and incubation with CM, although to a lesser degree. In conclusion, porcine homologous OEC co-culture and CM incubation specifically affect sperm function. However, we propose that it is OEC co-culturing, rather than OEC-CM, that has the greater influence.

Effect of LH Treated Ovine Oviductal Epithelial Cell Co-Culture System on Murine Pre-Embryo Development

Background This study was designed to develop a new co-culture system, assess the effect of luteinizing hormone (LH) using sequential media to promote development and increase the quality of 2-cell murine embryos through the 8-16 cell stage to morula and blastocyst stages. Materials and methods Monolayers for co-culture were prepared from ovine oviduct epithelial cells (OOEC) in DMEM/F12 medium and in-vivo-fertilized 2-cell embryos were collected by flushing from superovulated mice. Co-culture media was treated with 10ng/ml LH. For the control groups, embryos were cultured solely in G1/G2™Ver.5 drop s and containing LH; and on OOEC monolayers in G1/G2™Ver.5 drop s alone and containing LH as the experimental groups. Development and quality rates were determined for all embryos daily and statistically compared. At the end of the cultivation period, differentially stained trophectoderm (TE) and inner cell mass (ICM) of expanded blastocysts from each group were examined microscopically. Results The embryos cultured on an OOEC monolayer in G1/G2™Ver.5 drops treated with LH had a significantly higher developmental rate than those of the group without LH and the control groups (p≤0.05). The blastocysts from the LH treated co-culture, in comparison with the group without LH and the control groups, also had a significantly higher mean cell number (p≤0.05). Conclusion These findings suggest that elevated periovulatory LH levels may promote preimplantation embryo development. These results have important implications for assisted reproductive technologies in which co-cultures are used to improve pregnancy rates. OOEC cell co-culture system treated by LH could improve in vitro preimplantation embryo development both in terms of quality (increasing blastocyst cellularity) and developmental rate.

Somatic cell nuclear transfer in buffalos: effect of the fusion and activation protocols and embryo culture system on preimplantation embryo development

The present study was conducted primarily to evaluate several factors that affect the nuclear transfer programme in water buffalos, in which relatively few studies have been performed. Embryos reconstructed with quiescent fetal fibroblasts and metaphase II cytoplasts were matured for 24 h, and activation was found to be comparatively better than in those matured for 30 h. A significantly higher proportion of embryos fused (52.0 +/- 1.9) and cleaved (51.2 +/- 1.7) when the couplets were fused 4-6 h before activation than when fused and activated simultaneously (46.5 +/- 1.6 and 44.5 +/- 2.0, respectively). Development of nuclear transfer embryos to the blastocyst stage (4.8 +/- 2.2) was supported by a commercially available sequential medium, and cleavage (76.5 +/- 2.8) was significantly higher in this medium compared with cleavage in TCM-199 with oviduct epithelial cell coculture (45.6 +/- 1.5) and synthetic oviduct fluid (21.8 +/- 6.6). Of the 16 cloned embryos transferred, none resulted in pregnancy. The present study demonstrates that optimal numbers of cloned buffalo blastocysts can be obtained from oocytes matured for 24 h, fused 3-4 h before activation and cultured in a commercially available sequential media (G1/G2), thus providing further information to enable successful nuclear transfer in buffalos.

Successful use of oviduct epithelial cell coculture for in vitro production of viable red deer ( Cervus elaphus) embryos

Techniques for in vitro production (IVP) of viable embryos have been thoroughly developed in several domestic species in view to improve breeding efficiency. When applied to wild life, these techniques may also help the maintenance of biodiversity through amplification of sparse animals offspring and facilitation of genetic material exchange. During the successive steps of IVP, i.e. oocyte in vitro maturation (IVM), fertilization (IVF) and early embryo development (IVD) to the blastocyst stage, gametes and embryos are faced with unusual environment, including oxidative stress, known to be detrimental to their survival. In the present study, starting from methods developed in domestic species, we have adapted IVP to produce viable red deer embryos. In a first experiment, cumulus cells were removed from in vitro matured oocytes either before or after IVF. The presence of cumulus cells during IVF did not affect final cleavage or development rates. In a second experiment, in vitro matured oocytes were fertilized in the presence of cumulus cells and cultured in SOFaaBSA medium alone or in the presence of ovine oviduct epithelial cell (oOEC) monolayer. Whereas, oviduct cells did not improve the cleavage rate, they significantly increased the rate of embryos reaching the blastocyst stage (from 3 to 25% of total oocytes). Ten blastocysts from oOEC coculture were transferred after freezing and thawing to five recipient hinds and gave rise to three pregnancies. The three pregnant hinds gave birth to three live and normal calves.

Effects of bovine oviduct epithelial cells, fetal calf serum and bovine serum albumin on gene expression in single bovine embryos produced in the synthetic oviduct fluid culture system

In this study the synthetic oviduct fluid (SOF) system with bovine oviduct epithelial cell (BOEC) co-culture is compared with an SOF system with common protein supplements. One thousand six hundred bovine embryos were cultured in SOF media supplemented with BOEC, fetal calf serum (FCS) and bovine serum albumin (BSA). Eight different culture groups were assigned according to the different supplementation factors. Developmental competence and the expression levels of five genes, namely glucose transporter-1 (Glut-1), heat shock protein 70 (HSP), connexin43 (Cx43), (2)-actin (ACTB) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH), analysed as mRNA by using reverse transcription-polymerase chain reaction, were measured on bovine embryos cultured for 9 days. Gene expression of these in vitro-produced embryos was compared with the gene expression of in vivo-produced embryos. There was no significant difference found in embryo developmental competence between the Day 9 embryos in BOEC co-culture, FCS and BSA supplements in SOF media. However, differences in gene expression were observed. With respect to gene expression in in vivo and in vitro embryos, BOEC co-culture affected the same genes as did supplementation with FCS and BSA. HSP was the only gene that differed significantly between in vitro and in vivo embryos. When the different in vitro groups were compared, a significant difference between the BOEC co-culture and the FCS supplementation groups due to Glut-1 expression was observed.

The effect of oviductal epithelial cell co-culture during in vitro maturation on sow oocyte morphology, fertilization and embryo development

In vitro embryo production in the sow is challenged by poor cytoplasmic maturation, low sperm penetration and low normal fertilization, leading to the development of poor quality blastocysts containing a small number of nuclei. In prepubertal gilt oocytes, the presence of porcine oviductal epithelial cells (pOECs) during maturation increases cytoplasmic maturation and blastocyst development. These aspects, as well as blastocyst quality, may be improved when adult sow oocytes are matured with pOEC. Therefore, the effect of the presence of pOEC on sow oocyte morphology, fertilization and the progression of embryo development was evaluated. The pOEC were cultured in M199 for 18 h, then cultured in NCSU23 for 4 h before the oocytes were added. Oocytes from 2 to 6 mm follicles were matured in 500 μl NCSU23, with eCG and hCG, for 24 h, and then cultured with or without pOEC, in NCSU23 without hormones, for 18 h. In vitro fertilization took place in modified Tris-buffered medium, for 6 h, and the presumptive zygotes were then cultured for 162 h in NCSU23. Morphology of the IVM oocytes was compared to that of immature oocytes and in vivo matured MII oocytes from slaughtered sows in estrus. The in vitro matured oocytes had a greater diameter and a wider perivitelline space than the immature and in vivo matured MII oocytes ( P<0.01). Penetration, polyspermy and pronucleus formation did not differ between the pOEC and Control groups, although the total penetration rate was higher for the Control oocytes (26% versus 39%; P<0.01). Fewer blastocysts developed in the pOEC group than in the Control group (19% versus 27%; P<0.01), but blastocyst growth was accelerated, leading to a higher percentage of hatched blastocysts (3% versus 10%; P<0.01). Finally, the average blastocyst cell number was higher in the pOEC group (47 versus 40; P<0.05) and a greater percentage of blastocysts contained a superior number of nuclei. In conclusion, the addition of pOEC during the second half of in vitro maturation resulted in fewer blastocysts formed, but of those blastocysts that did form the quality was improved.

Effects of bovine serum albumin on function of cryopreserved stallion spermatozoa during medium culture and uterine tube epithelial cell coculture

Abstract Objective To compare function of cultured cryopreserved stallion spermatozoa in a modified Tyrode’s medium (TM), with or without bovine serum albumin (BSA), or in uterine tube (oviduct) epithelial cell (OEC) coculture in TM, with or without BSA. Sample Population Cryopreserved spermatozoa from 6 proven stallions and OEC from bovine reproductive tracts in follicular phase. Procedure Thawed spermatozoa were cultured in TM, with or without BSA, or cocultured with OEC monolayers in TM, with or without BSA. Percentages of capacitated and acrosome-reacted spermatozoa were measured at 5 hours for TM cultures. Spermatozoal survival and motility characteristics were observed over time for all culture methods. Number of spermatozoa attaching to OEC were compared for cocultures. Results Use of TM without BSA altered spermatozoal function in cell-free medium culture and OEC coculture. A higher percentage of spermatozoa were acrosome reacted in TM with BSA, although percentages of capacitated spermatozoa did not differ. Spermatozoa survived longer and maintained superior motion in TM culture without BSA and in OEC cocultures. More spermatozoa were able to attach to OEC in TM without BSA. Conclusions Incubation of cryopreserved spermatozoa in media with BSA resulted in rapid decrease in percentage of intact, motile spermatozoa and limited their ability to interact with OEC. Clinical Relevance Current culture media used for assisted reproduction techniques in horses do not provide functionally capacitated spermatozoa. Removal of BSA from such media improves spermatozoal quality and survival. (Am J Vet Res 1999;60: 363–367)

Coculture of Human Sperm With Bovine Oviduct Epithelial Cells Decreases Sperm Chromatin Structural Changes Seen During Culture in Media Alone

Objective: To compare sperm chromatin structural changes seen in media only culture or in coculture with bovine oviduct epithelial cells. Design: Three freshly ejaculated and three cryopreserved sperm samples in media culture or in oviduct epithelial cell coculture. Sperm in each treatment were evaluated by the sperm chromatin structure assay during a 72-hour time course. Setting: An academic research laboratory. Patient(s): Normospermic donors with children. Intervention(s): Semen collection through masturbation after 48 hours of abstinence. Main Outcome Measure(s): The sperm chromatin structure assay using flow cytometry to detect the susceptibility of sperm in either treatment to denaturation of DNA in situ. Result(s): The sperm chromatin structure assay data differed for sperm type (fresh or cryopreserved), over time, and between treatments within 6 hours of culture. In oviduct epithelial cell coculture, fresh sperm chromatin structure assay values for fresh sperm were stable, whereas in control medium higher chromatin degeneration levels were seen by 10 hours. For cryopreserved sperm, chromatin degeneration had increased by 1 hour postthaw in both treatments, although levels were higher in the control treatment thereafter. Conclusion(s): Sperm chromatin structural changes occur over time in culture. Such changes were observed within 2 hours for cryopreserved sperm. Coculture of sperm with oviduct epithelial cells results in a stabilizing effect for sperm against chromatin changes.

Effect of estrogen-treated porcine ampulla oviductal epithelial cells on early embryonic development in vitro and characterization of their protein synthetic activity.

Recent studies by Buhi et al. have demonstrated that estrogen (E2) is responsible for the induction of de novo synthesis and secretion of certain oviductal secretory proteins (OSP) and inhibition of other OSP in porcine oviductal explant cultures. The present work was undertaken to evaluate the effect of E2-treated oviductal epithelial cell coculture on the development of early porcine embryos derived from in vitro matured and fertilized oocytes. In vitro synthesis of secretory proteins by E2-treated oviductal cells used for coculture was also investigated by one-dimensional (1D) and two-dimensional (2D) sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE). The results showed that the cleavage rate was significantly enhanced by coculturing fertilized eggs with E2-treated oviductal epithelial cells. The in vitro protein synthetic pattern of oviductal secretory proteins was influenced by E2 treatment. These variations included the disappearance of one protein (82,000 M(r)) and the appearance of another (33,000 M(r)) in the E2-treated group as assessed by 1D-SDS-PAGE. Additional proteins of M(r) 97,000 and an M(r) 36,000-45,000 complex were increased in abundance by the E2 treatment. Analyses by 2D-SDS-PAGE revealed three major E2-dependent proteins, of M(r) 45,000 (pI 5.5), 43,000 (pI 5.5) and a 36,000-45,000 M(r) (pI 4.8) protein complex, whereas polypeptides of M(r) 97,000 (pI 5.1), 36,000 (pI 8.0) and 25,000 (pI 6.8) were inhibited by E2 treatment. The results demonstrated that porcine epithelial cell protein synthetic patterns are influenced by E2 treatment and that estradiol treatment of oviductal cells may increase the rate of zygote cleavage during early development in vitro in pigs.

What is the relationship between the metabolism of preimplantation embryos and their developmental competence?

What is the relationship between the metabolism of preimplantation embryos and their developmental competence?

In vitro fertilization and development of llama () oocytes using epididymal spermatozoa and oviductal cell co-culture

A study was designed to determine the feasibility of developing in vitro maturation, fertilization and culture systems utilizing follicular oocytes and epididymal spermatozoa collected from llamas at slaughter. From a total of 1324 cumulus oocyte complexes (COCs) recovered, 972 were cultured in 50-ul drops of TCM-199 medium with 10% heat inactivated steer serum (DBS) and hormones for 30 h. After maturation, the oocytes were randomly allocated into 4 groups in a 2x2 factorial design: cumulus-enclosed oocytes, 2 ug/ml heparin (Group 1); cumulus-enclosed oocytes, 5 ug/ml heparin (Group 2); denuded oocytes, 2 ug/ml heparin (Group 3); and denuded oocytes, 5 ug/ml heparin (Group 4). Denuded oocytes were obtained for groups 3 and 4 by vortexing. Epididymides were also collected at slaugther and fresh spermatozoa (for each replicate) were obtained by mincing the cauda epididymis with a scalpel blade. A total of 721 oocytes were inseminated with 2-3 x 10(6) epididymal spermatozoa/ml in a 50-ul drop of FERT-TALP medium. After 18 h of in vitro insemination, 234 oocytes were placed in a llama oviductal epithelial cell (LLOEC) co-culture in TCM-199 for 9 d. All cultures were done at 38.5 degrees C under 5% CO(2) in air with high humidity. The rate of fertilization, initial cleavage and development in co-culture were evaluated and compared. Of 192 oocytes examined for signs of fertilization, 56 (29.2%) were penetrated by spermatozoa with 57.1% (32 56 ) of the penetrated oocytes having a male and female pronucleus. There were no differences among treatment groups in total fertilization. However, the frequency of oocytes fertilized normally tended to be higher in the denuded oocytes 67.7% (21 31 ) than the oocytes inseminated with cumulus cells 44.0% (11 25 ) independent of heparin concentration (P<0.06). The total embryo development rate to the 2 cells to blastocyst stage was 32.1% (75 234 ). There was no difference in development rate between groups. From the 234 oocytes co-cultured in LLOEC for 9 d, 15.8% developed into 2 to 16 cells, 5.6% into morulae, 6.0% into early/expanded blastocysts and 4.7% into hatching/hatched blastocysts. The results indicate that an in vitro fertilization system is possible in the llama utilizing slaughterhouse material and that llama oocytes can be fertilized in the presence of heparin and epididymal spermatozoa.

Ability of epididymal or ejaculated bull spermatozoa to bind to cow zonae before and after oviduct epithelial cell co-culture

Both bone marrow stromal cells (BMSC) and olfactory ensheathing cells (OEC) have been demonstrated experimentally as promising for therapy of spinal cord injury (SCI). However, clinical use may be constrained by the margin neuronal differentiation capacity of BMSC as well as the limited number of isolatable OEC. This study therefore tested the efficacy of co-grafting human BMSC and OEC in treating thoracic SCI.Rat SCI models were created with cushion forces. OEC were labeled with Hoechst 33342 and BMSC with BrdU or GFP. BMSC, OEC and BMSC plus OEC were injected into the injured sites of rat spinal cords. Histologic, electrophysiologic and functional approaches were applied to assess the effects of transplantation of these cell types.Behavioral evaluation showed an improvement in animals with all cell-based treatments. The co-graft led to significantly higher gait scaling. The latency of transcranial magnetic motor-evoked potential (tcMMEP) responses was also better restored in the co-graft group. Larger numbers and sizes of axon bundles through the transitional zone between the normal and injured regions were observed in the co-graft animals in comparison with all other animals. Transplanted bone marrow stromal cells were identified as neurofilament-positive in the co-grafted animals although the number of glial fibrillary acidic protein-positive cells remained the same in all groups.Taken together, our results suggest that the combined use of BMSC and OEC may provide an improved approach for the treatment of SCI.