Lee, S. L.;J. G. Yoo;Park, G. J.;Lee, H. J.;S. Y. Choe
Proceedings of the KSAR Conference
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2001.10a
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pp.62-62
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2001
Development of effective activation protocols is of great importance for improving the success of cloning and subsequent transgenic. Three methods for oocyte activation, including 5μM ionomycin (5 min) alone, ionomycin+1.9 mM 6-dimetylaminopurine (DMAP, 3 hrs) and ionomycin+10㎍/㎖ cycloheximide(CHX, 3 hrs) were compared for their effects of pronuclei(PN) formation, development, developmental velocity and ploidy of parthenotes to IVF control in bovine. In group of ionomycin+DMAP, the oocytes having more 3 PN were significantly(P〈0.05) higher than in groups of ionomycin alone and of ionomycin+CHX (45.5% vs. 0 and 0%, respectively). Activation with the ionomycin alone, ionomycin+DMAP and ionomycin+CHX resulted in cleavage rates of 30, 85.5 and 57.9%, respectively. The blastocysts rate of parthenotes activated by ionomycin+DMAP treatment was significantly higher (12.3%, P〈0.05) than those of other treated groups. Chromosome analysis shows that ionomycin+DMAP treatment greatly increases the incidence of chromosomal abnormality of the parthenotes. When compared the developmental velocity at 24 hrs after insemination and activation, 27% eggs in IVF control and 55% in DMAP treatment out of total cleaved eggs developed to 2-cell stage, respectively. Developmental velocity of parthenotes activated by ionomycin +DMAP treatment was significantly (P〈0.05) faster than others. From the results, we may conclude that DMAP treatment to the oocytes accelerates developmental velocity resulting in both the higher incidence of chromosome abnormality and of PN formation suggesting that CHX combined with ionomycin is suitable DMAP for the purpose of successful nuclear transplantation.
Development of effective activation protocols is of great importance for improving the success of cloning and subsequent transgenic. Three methods for oocyte activation, including 5$\mu$M ionomycin (5 min) alone, ionomycin + 1.9 mM 6-dimetylaminopurine (DMAP, 3 hrs) and ionomycin + 10 $\mu\textrm{g}$/ml cycloheximide (CHX, 3 hrs) were compared for their effects of pronuclei (PN) formation, development, developmental velocity and ploidy of parthenotes to IVF control in bovine. In group of ionomycin + DMAP, the oocytes having more 3PN were significantly (P<0.05) higher than in groups of ionomycin alone and of ionomycin + CHX (45.5% vs. 0 and 0%, respectively). Activation with the ionomycin alone, ionomycin + DMAP and ionomycin + CHX resulted in cleavage rates of 30, 85.5 and 57.9%, respectively. The blastocysts rate of parthenotes activated by ionomycin + DMAP treatment was significantly higher (12.3%. p<0.05) than those of other treated groups. Chromosome analysis shows that ionomycin + DMAP treatment greatly enhances the incidence of chromosomal abnormality of the parthenotes. From the results, we may conclude that DMAP treatment to the oocytes accelerates developmental velocity resulting in both the higher incidence of chromosome abnormality and of PN formation, and strongly suggest that CHX combined with ionomycin is better than DMAP for the purpose of successful nuclear transplantation. Developmental velocity of parthenotes activated by ionomycin + DMAP treatment was significantly (P<0.05) faster than others.
This study was carried out to determine the effects of ionomycin and 6-dimethylaminopurine (6-DMAP) treatments on parthenogenesis of rabbit oocytes. The oocytes were randomly assigned to the activation treatments with either ionomycin plus 6-DMAP or electric stimulation. The oocytes were colected from the oviducts of superovulated rabbits at 13~14 hours and 19~20 hours post hCG injection and were activated with 5$\mu$M ionomycin for 5 min and 2 hours incubation in 2mM 6-DMAP. The other oocytes were stimulated by three pulses of 3.6kV/cm for 60 $\mu$sec each 30 min apart, starting 19 hours post in hCG in 0.28M mannitol solution with 100$\mu$M Ca2+ and Mg2+. The results obtained were summarized as follows: 1. Following treatment of the oocytes with ionomycin plus 6-DMAP, the cleavage rate and in vitro developmental rate to blastocyst were significantly(P<0.01) higher in the oocytes collected bet ween 19~20 hours than between 13~14 hours after hCG injection. 2. When the oocytes were treated with ionomycin plus 6-DMAP, 85(98.8%) of 86 treated oocytes extruded the second polar bodies, with the entire chromatin complements outside ooplasm. However when the oocytes were restored during subsequent incubation in the drug-free medium, the cytoplasts regain their full capacity for parthenogenetic activation and nuclear remodelling. 3. The cleavage rate and the in vitro developmental rate to blastocyst were not significantly different in the oocytes activated by ionomycin plus 6-DMAP treatment(91.2 and 45.6%) or electrical stimulation(89.6 and 34.3%).
This study was to determine the effect of ionomycin and 6-dimethylaminopurine (6-DMAP) and/or elcetrical stimulation on the oocyte activation and production of rabbit nuclear transplant embryos. The oocytes were collected from the oviduct of superovulated rabbits at 14 h post hCG injection and cultured in TCM-199 containing 10% FBS until 19 h post hCG injection. To determine the optimum concentration and exposure time of 6-DMAP, some oocytes were activated with 5 $\mu$M ionomycin for 5 min and then in 2.0 mM 6-DMAP for 0.5 to 3.0 h, or in 1.0 to 3.0 mM 6-DMAP for 2.0 h. Other control oocytes were stimulated electrically(3X, 1.25 kV/cm, 60 $\mu$sec) in 0.3 M mannitol solution supplemented with 100 $\mu$M CaCl$_2$ and MgCl$_2$. The nuclear donor embryos of 8-cell stage were synchronized to G$_1$ phase of 16-cell stage, and the recipient cytoplasms were obtained from removal of the first polar body and a portion of membrane bound cytoplasm of the oocytes collected at 15 h post hCG injection. A separated blastomere was injected into the perivitelline space of the enucleated oocytes. The oocytes injected with nucleus were cultured until 19 h post hCG and then electrofused and activated by electrical stimulation with or without ionomycin and 6-DMAP. These nuclear transplant embryos were cultured in TCM-199 containing 10% FBS in 39˚C, 5% CO2 incubator for 120 h. For the oncytes activated parthenogenetically with electrical stimulation with or with-out ionomycin and the various concentration of exposure time of 6-DMAP, the highest cleavage(92.3%) and development to blastocyst stage(41.0%) were resulted from the oocytes activated by ionomycin and 2.0 mM 6-DMAP for 2.0 h, which were found to be significantly(P<0.05) higher than the cleavage(45.2%) and developement to blastocyst stage(14.3%) from the oocytes activated with electrical stimulation. The significantly(P<0.05) more oocytes(71.4%) developed to 4 cell stage at 24 h post activation by ionomycin and 6-DMAP than those by electrical stimulation(18.9%). For the nuclear transplant embryos, the cleavage rate was similarly high in oocyte activation by electrical stimulation with(79.4%) or without ionomycin and 6-DMAP(70.5%). However, the embryo development to blastocyst stage was significantly(P<0.05) higher in oocyte activation by electrical stimulation with ionomycin and 6-DMAP(44.4%) than by electrical stimulation only(25.0%). The significantly(P<0.05) more nuclear transplant embryos(45.6%) developed to 4 cell stage at 18 h post activation by electrical stimulation with ionomycin and 6-DMAP than those by electrical stimulation only(10.6%). These results indicated that the supplemental oocyte activation by ionomycin and 6-DMAP with electrical stimulation enhanced and accelerated the preimplanted in vitro development of the rabbit nuclear transplant embryos.
Efficient oocyte activation is a key step for the success of nuclear transfer in cloning. Ionomycin sequentially combined with 6-DMAP is now widely used to activate normal oocytes for analytical studies of oocyte activation and to activate reconstructed oocytes after nuclear transfer. The present study investigated sources of oocytes, duration of ionomycin and 6-DMAP, laser and electric stimulation in goat oocyte activation in order to optimize the protocols. Goat ovaries were collected in individual abattoirs during the breeding season and were delivered to the laboratory within 6 h in saline with 100 IU/ml streptomycin and 0.05 mg/ml penicillin. The oocytes were denuded from the cumulus cell by pipetting with 0.2% hyaluronidase in PBS at 20~22 hr post maturation. Oocytes with the polar body were selected and assigned to four groups for parthenogenetic activation. To examine the effect of duration of ionomycin treatment, oocytes after 20~22 hr of maturation were treated with 2.5 uM ionomycin for 1 or 5 min times and then cultured in 2 mM 6-DMAP for 2 or 4 hr. The activated oocytes were cultured in mSOF at $38.5^{\circ}C$ in $CO_2$ 5%, $O_2$ 5% and $N_2$ 90% multi incubator. Cleavage and blastocyst development was observed at 48 hr and day 8 of culture $in$$vitro$, respectively. Activation rates of oocytes exposed to ionomycin for 1 min(86.4%) were significantly higher than those treated for 5 min(74.3%) duration. This indicated that 1 min ionomycin treatment was most suitable for activation of goat oocytes. The duration of 6-DMAP treat duration was in 2 mM 6-DMAP for 2 hr after 1 min exposure to 2.5 uM ionomycin. The activation rate of oocytes incubated in 6-DMAP for 2 hour(82.5%) was significantly higher than those in oocytes treated with 4 hr(75.5%).
In this study I report that in vitro development rates of bovine nuclear transfer embryos activated either with boar sperm cytosolic factor (SCF) or with ionomycin followed by cycloheximide (CHX) and subsequent in vivo developmental rates after embryo transfer are related to blastocyst quality as evaluated by apoptosis analysis. SCF was extracted from porcine semen then purified for post-activation injection after nuclear transfer. The optimal timing for SCF injection was determined to be at least 22 h post-IVM for parthenogenetic activation of bovine oocyies. A total of 364 oocytes were successfully enucleated and 268 (73.6%) fused and were injected with SCF. The survival rate of fused and injected embryos was 109/113 (96.5%) after 2 h. The cleavage rates of nuclear transfer embryos after 3 d of culture in the ionomycin/CHX treated group were significantly higher than those of the SCF-activated group (93.3% vs 81.7%, p<0.01, respectively). However, at 7 d and 9 d there was no significant difference between the total developmental rates to blastocyst for either treatment group. Total blastocyst cell numbers were also not significantly different between the two activation treatments (ionomycin/CHX: 149.5${\pm}$7.7 vs. SCF: 139.3${\pm}$4.4 cells). In contrast, the apoptotic levels in the SCF blastocysts were higher than those produced after the chemical treatment (28.2${\pm}$5.1% vs. 8.8${\pm}$0.6%, respectively). A total of 18 expanded or hatching blastocysts was transferred to nine synchronized recipients in each activation group; 5/9 (55.5%) and 2/9 (22.2%) were pregnant at 40 d in the ionomycin/CHX treatment and SCF activated group, respectively. However, only one went to term in the ionomycin/CHX treatment while none of the pregnancies from the SCF group were maintained by 90 d. In conclusion, these results suggest that SCF derived from different species is a limited activator to be used for activation after bovine nuclear transfer in lieu of a chemical activation protocol.
Nugroho, Agung Endro;Wahyono, Wahyono;Wahyuono, Subagus;Maeyama, Kazutaka
Advances in Traditional Medicine
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v.10
no.3
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pp.200-207
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2010
The fruits of Piper cubeba L. are used traditionally to treat respiratory disorders in Indonesia. In order to determine the compounds responsible for this activity, the fruits were extracted with nhexane followed by ethanol to give n-hexane and ethanol extracts. Based on tracheospasmolytic assay on these two extracts, the n-hexane extract was more active to inhibit trachea contraction than that of ethanol extract. Upon bioassay guided isolation of the n-hexane extract, a tracheospasmolytic active compound was isolated and identified as dihydrocubebin [(3,4),(3',4')-bis-methylenedioxy-9,9'dihydroxylignan] $(\underline{1})$. Compound $\underline{1}$ was tested further for its ability to inhibit histamine released from mast cells, using rat basophilic leukemia (RBL-2H3) cell line and rat peritoneal mast cells RPMCs) as models; and $DNP_{24}$-BSA, thapsigargin, ionomycin, compound 48/80 and PMA were used as inducers for histamine released from mast cell. The test result showed that $\underline{1}$ inhibited histamine release from RBL-2H3 cells induced by $DNP_{24}$-BSA, thapsigargin and ionomycin. In addition, $\underline{1}$ suppressed histamine release from RPMC induced by either thapsigargin or ionomycin. However, $\underline{1}$ did not inhibit histamine release from RPMC induced by either compound 48/80 or combination PMA-sub optimum dose of ionomycin. Therefore, it was concluded that the inhibitory effects of $\underline{1}$ on the histamine released from mast cells may involve mechanisms related to intracellular $Ca^{2+}$ signaling events or downstream processes of intracellular $Ca^{2+}$ signaling in mast cells.
Jung Ho Lee;Brian H Lee;Soyoung Jeong;Christine Suh-Yun Joh;Hyo Jeong Nam;Hyun Seung Choi;Henry Sserwadda;Ji Won Oh;Chung-Gyu Park;Seon-Pil Jin;Hyun Je Kim
Genomics & Informatics
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v.21
no.2
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pp.18.1-18.11
/
2023
Immunologists have activated T cells in vitro using various stimulation methods, including phorbol myristate acetate (PMA)/ionomycin and αCD3/αCD28 agonistic antibodies. PMA stimulates protein kinase C, activating nuclear factor-κB, and ionomycin increases intracellular calcium levels, resulting in activation of nuclear factor of activated T cell. In contrast, αCD3/αCD28 agonistic antibodies activate T cells through ZAP-70, which phosphorylates linker for activation of T cell and SH2-domain-containing leukocyte protein of 76 kD. However, despite the use of these two different in vitro T cell activation methods for decades, the differential effects of chemical-based and antibody-based activation of primary human T cells have not yet been comprehensively described. Using single-cell RNA sequencing (scRNA-seq) technologies to analyze gene expression unbiasedly at the single-cell level, we compared the transcriptomic profiles of the non-physiological and physiological activation methods on human peripheral blood mononuclear cell-derived T cells from four independent donors. Remarkable transcriptomic differences in the expression of cytokines and their respective receptors were identified. We also identified activated CD4 T cell subsets (CD55+) enriched specifically by PMA/ionomycin activation. We believe this activated human T cell transcriptome atlas derived from two different activation methods will enhance our understanding, highlight the optimal use of these two in vitro T cell activation assays, and be applied as a reference standard when analyzing activated specific disease-originated T cells through scRNA-seq.
Immunosuppressive therapy after organ transplantation is routinely used to prevent rejection of the organ, because this decreases the risk of adverse events, infection, and malignancies. Recently, ursodeoxycholic acid (UDCA), which is isolated from the dried bile of adult Chinese bears, has been shown to reduce the incidence and severity of acute rejection of liver allograft during early phase of liver transplantation. Therefore, in this study, we investigated the effect of UDCA on the proliferation of splenocytes exposed to PMA plus ionomycin. Our results demonstrated that UDCA decreased the splenocytes' proliferation in a dose-dependent manner. The decreased cell proliferation was accompanied with the decreased secretion of cytokines such as IL-2, IFN-${\gamma}$ and TNF-${\alpha}$. In addition, the pretreatment of UDCA on splenocytes stimulated with PMA plus ionomycin decreased the mRNA levels of cytokines (IL-2, IFN-${\gamma}$ and TNF-${\alpha}$) and costimulatory molecules (B7.2 and PD-L1). These results suggest the beneficial effect of UDCA on organ transplantation by decreasing lymphocyte proliferation.
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