scholarly journals Rat in vitro spermatogenesis promoted by chemical supplementations and oxygen-tension control

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Takafumi Matsumura ◽  
Takuya Sato ◽  
Takeru Abe ◽  
Hiroyuki Sanjo ◽  
Kumiko Katagiri ◽  
...  
Keyword(s):  
Oxygen Tension ◽  
Culture Medium ◽  
Animal Species ◽  
Culture Method ◽  
Tension Control ◽  
Significant Progress ◽  
In Vitro Spermatogenesis ◽  
Lower Oxygen ◽  
Rat Spermatogenesis

AbstractIn vitro spermatogenesis (IVS) using air–liquid interphase organ culture method is possible with mouse testis tissues. The same method, however, has been hardly applicable to animals other than mice, only producing no or limited progression of spermatogenesis. In the present study, we challenged IVS of rats with modifications of culture medium, by supplementing chemical substances, including hormones, antioxidants, and lysophospholipids. In addition, reducing oxygen tension by placing tissues in an incubator of lower oxygen concentration and/or applying silicone cover ceiling on top of the tissue were effective for improving the spermatogenic efficiency. Through these modifications of the culture condition, rat spermatogenesis up to round spermatids was maintained over 70 days in the cultured tissue. Present results demonstrated a significant progress in rat IVS, revealing conditions commonly favorable for mice and rats as well as finding rat-specific optimizations. This is an important step towards successful IVS in many animal species, including humans.

92 Culture method for long-distance transport of bovine embryos derived from IVF before blastulation using microtubes

2019 ◽  
Vol 31 (1) ◽  
pp. 172
Author(s):  
T. Yamanouchi ◽  
H. Matsuda ◽  
K. Ogata ◽  
Y. Hashiyada
Keyword(s):  
Culture Medium ◽  
Liquid Paraffin ◽  
Calf Serum ◽  
Petri Dish ◽  
Culture Method ◽  
Optimal Number ◽  
Blastocyst Development ◽  
Long Distance

In vitro-produced (IVP) embryos are more easily damaged by cryopreservation than in vivo-derived embryos. Therefore, transportation of fresh IVP embryos in a manner that can maintain viability is necessary. This study was conducted to determine the preferable culture conditions for transport of embryos at 5 days post-insemination (dpi) in 1.5-mL microtubes. Cumulus-oocyte complexes derived from an abattoir were matured and then inseminated with frozen-thawed semen. Presumptive zygotes were cultured in mCR1aa (CR1)+5% calf serum (CS) until use. In Exp. 1, embryos with 5 blastomeres at 5 dpi were randomly assigned to 1 of 3 groups: 25mM Hepes-CR1aa (H-CR1)+5% CS or 25mM Hepes-M199 (H-M199)+5% CS in air, or CR1 in 5% CO2. Embryos were cultured in microdrops overlaid with liquid paraffin in a petri dish for 48h at 38.5°C. In Exp. 2, the optimal number of embryos to culture per microtube was assessed. Presumptive zygotes were cultured in groups of 20, 40, or 80 in 1mL of CR1 covered with liquid paraffin in microtubes in an incubator at 38.5°C in 5% CO2 until 7 dpi. For Exp. 3, culture of embryos in microtubes in a portable incubator was tested. At 5 dpi, 5-cell embryos (n=17 to 36 per microtube) were statically cultured in 1mL of CR1 or H-CR1 in microtubes in a portable incubator set at 38.5°C for 48h. The CR1 was pre-equilibrated in an incubator in 5% CO2 for 24h before use. Embryos were harvested from microtubes after 48h and were then cultured in microdrops of CR1 overlaid with liquid paraffin in a petri dish in an incubator at 38.5°C in 5% CO2 until 8 dpi. In Exp. 4, embryos (n=29 to 39 five-cell embryos per microtube) were transported in a portable incubator by land for 1000km over a period of 44h using the same conditions as in Exp. 3. Control embryos were statically cultured in microdrops of CR1 in an incubator in 5% CO2. Statistical analyses were carried out by ANOVA (Exp. 1 and 2), t-test (Exp. 3), or Fisher’s exact test (Exp. 4). In Exp. 1, there was no effect (P>0.05) of culture medium on blastocyst development at 7 dpi (27.6±2.3, 25.7±7.2, and 17.3±2.9% for CR1, H-CR1, and H-M199, respectively). In Exp. 2, blastocyst development at 7 dpi was not affected (P>0.05) by the number of presumptive zygotes cultured per microtube (43.6±8.3, 42.4±4.0, and 39.9±2.9% for 20, 40, and 80 presumptive zygotes, respectively). In Exp. 3, blastocyst development at 8 dpi was not affected (P>0.05) by culture medium (60.7±7.4 and 53.1±4.4% for CR1 and H-CR1, respectively); however, the pH of CR1 changed from 7.5 to 8.1 at 48h after culture. In Exp. 4, blastocyst development at 8 dpi was not affected (P>0.05) by transport (57.1, 64.4, and 75.5% for CR1, H-CR1, and control, respectively). These results indicate that IVP embryos harvested at 5 dpi can be transported by portable incubator with no effect on embryo development to the blastocyst stage. This work was supported by grants from the Project of the Bio-oriented Technology Research Advancement Institution, NARO (the special scheme project on advanced research and the development for next-generation technology).

Hypoxia Alters the Main Characteristics of the Hematopoietic Stem and Progenitor Cell Microenvironment in Vitro

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4803-4803
Author(s):  
Manja Wobus ◽  
Jing Duohui ◽  
David M Poitz ◽  
Katrin Müller ◽  
Rainer Ordemann ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Stem Cell ◽  
Osteogenic Differentiation ◽  
Oxygen Tension ◽  
Cell Phenotype ◽  
Low Oxygen ◽  
Hematopoietic Stem ◽  
Hypoxic Conditions ◽  
Lower Oxygen

Abstract Abstract 4803 Background: Hematopoietic stem and progenitor cells (HSPC) are located in a specialized microenvironment, called the stem cell niche, where their stem cell phenotype and differentiation are tightly regulated via interactions with the supporting mesenchymal stromal cells (MSC). These niches have been shown to be localized in regions with a lower oxygen tension which may also impact on the functional properties of MSC. For a better understanding to what extent hypoxia contributes to the establishment of an undifferentiated niche microenvironment that prevents inopportune differentiation of HSPC, we investigated MSC/HSPC co-cultures as well as MSC single cultures under low oxygen conditions. Design and Methods: Distribution, functional and phenotypical characteristics of CD34+ HSPC in hypoxic co-cultures (0.5% O2) were analyzed by flow cytometry. The effect of co-culture medium on the HSPC migration potential was tested in a transwell assay. The secretion of vascular endothelial growth factor A (VEGF-A), stromal-derived factor 1 (SDF-1), IL-6 and IL-8 by MSC was determined using ELISA whereas the expression of cell surface molecules was detected by flow cytometry. Moreover, the MSC proliferation as well as adipogenic and osteogenic differentiation was compared between hypoxic and normoxic culture conditions. Results: In the hypoxic co-culture, the adhesion of HSPC to the MSC layer was inhibited, whereas HSPC transmigration beneath the MSC layer was favoured. Increased VEGF-A secretion by MSC under hypoxic conditions, which enhanced the permeability of the MSC monolayer, was responsible for this effect. Furthermore, VEGF expression in hypoxic MSC was induced via hypoxia-inducible factor (HIF) signalling. Whereas IL-6 and IL-8 secretion were increased, SDF-1 expression by MSC was down-regulated under hypoxic conditions in a HIF-independent manner. The MSC immunophenotype which is characterized by expression of CD73, CD90, CD105, and CD166 was not significantly changed by hypoxia. Interestingly, a significant decrease of CD146 mRNA and protein expression levels was observed. The MSC proliferation was not significantly affected by lower oxygen tension. Culture of MSC in adipogenic induction medium for 14 days under hypoxia resulted in a reduced appearance of adipocyte-like cells containing lipid droplets and almost 50 % lower mRNA levels of fatty acid binding protein 2. The ALP activity as readout for osteogenic differentiation was decreased between 10% and 60% in hypoxic MSC. Conclusions: Low oxygen tension reduces the in vitro differentiation capacity and alters the cytokine secretion profile of primary human MSC. These functional changes may favour the homing and maintenance of quiescent HSC simulating the physiologically hypoxic niche conditions in vitro. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Cryopreservation of testicular tissue: an alternative to maintain the reproductive capacity in different animal species

2017 ◽  
Vol 47 (11) ◽  
Author(s):  
David Baruc Cruvinel Lima ◽  
Lúcia Daniel Machado da Silva
Keyword(s):  
Clinical Practice ◽  
Germ Cells ◽  
Animal Species ◽  
Testicular Tissue ◽  
Reproductive Capacity ◽  
Significant Progress ◽  
Breeding Programs ◽  
Artificial Breeding ◽  
Made In

ABSTRACT: Cryopreservation of testicular tissue enables the maintenance of reproductive capacity in different animal species, and contributes to the formation of gene banks for endangered species. The spermatogonia present in the testes can be grown in vitro and the sperm obtained can be used in artificial breeding programs. This review aimed to describe the main techniques of testicular cryopreservation, the main cryoprotectants used, as well as the progress made in different animal species thus far. In the last decade, significant progress has been made in obtaining viable and functional germ cells from testicular tissue. However, more research is needed to better establish protocols that can be used in clinical practice with various species.

scholarly journals A new microcirculation culture method with a self-organized capillary network

2020 ◽  
Author(s):  
Kei Sugihara ◽  
Yoshimi Yamaguchi ◽  
Shiori Usui ◽  
Yuji Nashimoto ◽  
Sanshiro Hanada ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Culture Medium ◽  
Culture Method ◽  
Inflammatory Cells ◽  
Capillary Network ◽  
The Self ◽  
Lung Fibroblasts ◽  
Collective Cell Migration ◽  
Self Organized

AbstractA lack of microcirculation has been one of the most significant obstacles for three-dimensional culture systems of organoids and embryonic tissues. Here, we developed a simple and reliable method to implement a perfusable capillary network in vitro. The method employed the self-organization of endothelial cells to generate a capillary network and a static pressure difference for culture medium circulation, which can be easily introduced to standard biological laboratories and enables long-term cultivation of vascular structures. Using this culture system, we perfused the lumen of the self-organized capillary network and observed a flow-induced vascular remodeling process, cell shape changes, and collective cell migration. We also observed an increase in cell proliferation around the synthetic vasculature induced by flow, indicating functional perfusion of the culture medium. We also reconstructed extravasation of tumor and inflammatory cells, and circulation inside spheroids including endothelial cells and human lung fibroblasts. In conclusion, this system is a promising tool to elucidate the mechanisms of various biological processes related to vascular flow.

Effect of culture Po2on macrophage (RAW 264.7) nitric oxide production

2001 ◽  
Vol 280 (2) ◽  
pp. C280-C287 ◽  
Author(s):  
Cynthia M. Otto ◽  
James E. Baumgardner
Keyword(s):  
Nitric Oxide ◽  
Cell Culture ◽  
Oxygen Tension ◽  
Inflammatory Responses ◽  
No Production ◽  
Inos Activity ◽  
Lower Oxygen ◽  
Oxygen Tensions

Macrophages are commonly cultured at a Po2of 149 Torr, but tissue macrophages in vivo live in an environment of much lower oxygen tension. Despite the many potential mechanisms for changes in oxygen tension to influence nitric oxide (NO) synthesis, there have been few reports investigating the effect of Po2on macrophage NO production. With the use of a culture chamber designed to rigorously control oxygen tension, we investigated the effects of culture Po2on macrophage NO production, inducible nitric oxide synthase (iNOS) activity, iNOS protein, and tumor necrosis factor production. NO production and iNOS activity were linearly related in the range of 39.4 to 677 Torr, but not in the range of 1.03 to 39.4 Torr. Therefore, results obtained in vitro for the high oxygen tensions commonly used in cell culture were quantitatively and qualitatively different from results obtained in cells cultured at the lower oxygen tensions that more accurately reflect the in vivo environment. The influence of oxygen tension on NO production has implications for cell culture methodology and for the relationship between microcirculatory dysfunction and inflammatory responses in rodent models of sepsis.

154 THE EFFECT OF OXYGEN TENSION ON IN VITRO DEVELOPMENT OF BOVINE EMBRYOS IN POLYDIMETHYLSILOXANE-BASED WELL OF THE WELL DISHES PREPARED UNDER ATMOSPHERIC OR REDUCED AIR PRESSURE

2010 ◽  
Vol 22 (1) ◽  
pp. 235
Author(s):  
T. Somfai ◽  
Y. Inaba ◽  
Y. Aikawa ◽  
M. Ohtake ◽  
S. Kobayashi ◽  
...  
Keyword(s):  
Oxygen Tension ◽  
Culture Medium ◽  
Production Method ◽  
Total Cell ◽  
Air Pressure ◽  
Bovine Embryos ◽  
Cell Numbers ◽  
Significant Difference ◽  
And Control

Polydimethylsiloxane (PDMS) is a non-toxic silicon compound. Its excellent optical characteristics and easy preparation make it a good candidate material for the molding of custom-shaped dishes for embryo culture. We investigated the feasibility of PDMS-based well of the well (WOW) dishes for in vitro culture of bovine embryos under different oxygen tensions. The WOW dishes with 25 micro-wells (each of 175 μm depth and 250 μm width in diameter arranged in 5 columns and 5 rows) were molded from PDMS prepared either under atmospheric (Experiment 1) or reduced (0.1 MPa) (Experiment 2) air pressure to remove air bubbles. Presumptive zygotes obtained by the in vitro maturation and fertilization of follicular oocytes were placed and cultured for 7 days in traditional micro-drops of culture medium (Control) or in the micro-wells of PDMS-based WOW dishes (PDMS-WOW), both covered by paraffin oil. The culture medium was CR1aa supplemented with 5% calf serum. The culture drop size was 125 μL (5 μL/oocyte) in both groups. Embryo development and blastocyst cell numbers between Control and PDMS-WOW groups were compared either under 20% or 5% O2 tensions. There was no statistical difference in cleavage and blastocyst rates (ranging between 82.3-86.4% and 34.0-45.8%, respectively) between Control and PDMS-WOW embryos irrespective of oxygen tension and dish production method. In Experiment 1, the mean total cell numbers in blastocysts were lower in the PDMS-WOW group than that in Control under 20% O2 (105.0 ± 5.5 and 130.4 ± 9.9, respectively) (P < 0.05, ANOVA); however, the application of 5% O2 significantly improved the cell numbers and eliminated the difference between the PDMS-WOW and Control groups (135.4 ± 6.2 and 148.0 ± 9.0, respectively). In Experiment 2, there was no significant difference in mean total cell numbers in blastocysts between the PDMS-WOW and Control either under 20% O2 (97.2 ± 5.7 and 103.9 ± 8.9, respectively) or 5% O2 (147.5 ± 12.1 and 157.3 ± 3.9, respectively). The numbers and rates of inner cell mass and trophectoderm cells did not differ between the Control and PDMS-WOW groups, irrespective of O2 tension and production method. Our results demonstrate that bovine embryos can develop to the blastocyst stage in PDMS-based WOW dishes; however, it may express detrimental effects on embryonic cell numbers, which can be neutralized by the application of low O2 tension during culture or reduced air pressure during the PDMS preparation. This work was supported by the Research and Development Program for New Bio-Industry Initiatives.

scholarly journals Cell-cycle manipulation of human leukemic progenitor cells with humoral adjustment in vitro

Blood ◽  
1981 ◽  
Vol 58 (1) ◽  
pp. 179-182 ◽  
Author(s):  
CH Park
Keyword(s):  
Cell Cycle ◽  
Progenitor Cells ◽  
Conditioned Medium ◽  
Culture Medium ◽  
Culture Method ◽  
Leukemic Cells ◽  
Agar Culture ◽  
Daily Feeding

Abstract The cell-cycle change of human leukemic colony-forming cells was studied using a new agar culture method featuring daily feeding of new culture medium with or without leukocyte conditioned medium (LCM). Leukemic cells could be kept out of cycle by withholding LCM from daily feeding and put back into cycle by adding LCM to the daily feeding.

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