- Email: [email protected]
C-1014
Abstracts / Cryobiology 69 (2014) 503–523 suppressed colony formation but promoted mesenchymal cell appearanced proliferation http://dx.doi.org/10.1016/j.cryobiol.2014.09.340
C-1012 Cholesterol-loaded cyclodextrin improves goat semen cryosurvival by enhancing sperm cholesterol content and osmotic tolerance V. Salmon 1, P. Leclerc 2, J. Bailey 2, 1 Centre de Recherche en Biologie de la Reproduction (CRBR), 909 Rue Monseigneur-Grandin Appt 201, Quebec G1V3X8, Canada, 2 Laval University, 2425, Rue de l’agriculture, Quebec GIV0A6, Canada. Email address: [email protected] The success of semen cryopreservation mainly resides in maintaining sperm membrane integrity and function after thawing. Cholesterol-loaded cyclodextrin (CLC) is used for in vitro incorporation of cholesterol into cells to protect them against cold temperature. We hypothesized that CLC treatment enhances sperm cholesterol content to increase its tolerance to osmotic shock and cryo-resistance, thereby improving fertility. Alpine goat sperm were treated ± 3 mg/ml CLC and lipids extracted by the Folch method, then cholesterol was quantified with Liebermann-Burchard reagent, which confirmed that CLC treatment increases the cholesterol content of fresh sperm in either PBS or skim milk extender. Sperm were then treated ± CLC in skim milk extender and cryopreserved. After thawing, sperm cholesterol dramatically fell, even in the presence of CLC, and likely explains the mechanism of ‘‘cryo-capacitation”. However, CLC treatment helped maintain a normal pre-freeze cholesterol level in the sperm after cryopreservation. Labelling sperm cholesterol with filipin confirmed this result on sperm membranes. Furthermore, fresh sperm in skim milk extender treated 3 mg/ml CLC and incubated for 20 min in hypo-, iso- and hyperosmotic PBS have increased hypoosmotic tolerance, corresponding to the beneficial effects of CLC at thawing. As expected, CLC treatment in skim milk extender improved sperm viability, motility and acrosome integrity after thawing. Furthermore, ultrasonography after artificial insemination revealed that sperm treated with CLC are 10% more fertile than control semen without CLC.
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C-1014 High survival of mouse oocytes and preimplantation embryos after vitrification in the absence of permeating cryoprotectants and ultra-rapid warming by an IR laser pulse B. Jin, P. Mazur, The University of Tennessee, Department of Biochemistry and Cellular and Molecular Biology, Room 191N Hoskins Library, White Street, Knoxville, TN 37996-0840, United States. Email address: [email protected] In a companion presentation at this meeting and in a full paper published 3/22/14 on line in Cryobiology, we have reported that when Metaphase II mouse oocytes or 2-cell mouse embryos are suspended in EAFS vitrification media that contain only one-third the concentration of solutes as standard, over 90% survive when assessed by osmotic/morphological criteria and up to 85% survive when assessed by the functional ability to undergo IVF and/or develop in vitro to expanded blastocysts, provided that they are warmed at 10,000,000 °C/min by a powerful pulse from an IR laser. The base 0.3 EAFS medium that we used contains ethylene glycol (EG) [0.70 molal], acetamide [0.71 molal], 70,000 MW Ficoll [0.0013 molal], sucrose [0.16 molal], and PBS salts [0.15 molal]. Variants included 0, 0.16, 0.25, 0.5, and 1.0 molal sucrose, and 0.0062 molal Ficoll. Sucrose, Ficoll, and the salts cannot penetrate the cells; the EG and acetamide can readily do so, but the 2-min exposure time is too short for this to occur. As a consequence, the cells are strongly dehydrated osmotically when vitrification is initiated. This raises the question of whether permeating solutes are needed to achieve high survivals after vitrification. In the companion presentation, we argued that the most important factor aside from ultra-rapid warming was the total molality (and hence, osmolality) of the medium. In the present presentation we address the matter of survival of not only oocytes, but of 2-cell and 8-cell embryos, and morluae and blastocysts vitrified in the total absence of permeating solutes. The morphological and functional survivals of vitrified 2-cell and 8-cell embryos were 92%; the survivals of vitrified oocytes and blastocysts were above 70%. All four of these survivals were obtained with laser-induced warming at 10,000,000 °C/min. If warming was slowed 100-fold to the previous standard maximum of 100,000 °C/min, morphological and functional survivals were zero. Since no one has heretofore warmed oocytes and embryos at the ultra-high rates used here, we believe that this is the first time it has been shown that these cells can be cryopreserved in a solution that is free of any permeating compounds.
http://dx.doi.org/10.1016/j.cryobiol.2014.09.341
http://dx.doi.org/10.1016/j.cryobiol.2014.09.343
C-1013 Cryopreservation of spermic milt in the model species Ambystoma tigrinum (Tiger salamander) for application in endangered salamanders R. Marcec 1, C. Langhorne 1, C. Vance 2, A. Kouba 2, S. Willard 1, 1 Mississippi State University, Room 244, Box 9655, Dorman Hall, 32 Creelman St., MS 39762, United States, 2 The Memphis Zoo, 2000 Prentiss Place, Memphis, TN 38112, United States. Email address: [email protected]
C-1015 Implications of the consequences of laser-induced ultra-rapid warming of mouse oocytes and embryos to vitrification theory and to the successful vitrification of other cell types P. Mazur, The University of Tennessee, Department of Biochemistry and Cellular and Molecular Biology, Room 191N Hoskins Library, White Street, Knoxville, TN 379960840, United States. Email address: [email protected]
In the face of the amphibian extinction crisis, captive assurance colonies have been established to preserve genetic diversity. Sadly, many captive assurance colonies fail due to reproductive cues which are not entirely understood. In addition, the majority of amphibian conservation and genome banking research has focused on anurans (frogs/toads), despite the fact that caudates (salamanders/newts) face a larger threat of extinction. Therefore, it is critical that assisted reproductive technologies, such as gamete cryopreservation and artificial fertilization, be developed as conservation tools for application in genetic management of threatened caudates. It was hypothesized that a modified anuran sperm freezing protocol could be successfully used in cryopreservation of Ambystoma tigrinum (tiger salamander) sperm as a caudate model. Spermiation in male tiger salamanders was hormonally induced via injection with hCG, LHRH, or a combination of these two hormones. Average spermic milt concentrations were 2.75 107(±7.2 106)/mL. Average total motility upon collection of fresh milt was 53.6% (±17.6%). After collection and initial analysis, fresh milt samples were diluted 1:1 in chilled cryoprotectant treatment solutions. They were then frozen in 0.25 mL French straws using a stepwise slowrate freezing process. Upon thawing, milt suspensions were diluted 1:10 with a 10% Holtfreter’s solution in order to activate the sperm for post thaw analysis. Frozen-thawed sperm in the 5% Me2SO treatment group had an average total motility of 19.1% (±15.8%) and sperm in the 5% Me2SO with 0.5% BSA treatment group had an average total motility of 21.75% (±14.8%). Early trials showed that caudate sperm are not susceptible to toxicity from several cryoprotective media. Moreover, initial fertilization trials indicate that frozen-thawed caudate sperm are capable of producing early cleavage stage embryos. Optimizing cryopreservation protocols for salamander sperm is an important step in building a global genetic resource bank for endangered caudates.
Jin, Kleinhans, and Mazur have reported in this meeting that up to 100% of oocytes and 2-cell embryos survive vitrification in a 3-fold dilution of EAFS medium if warmed at 10,000,000 °C/min by an IR laser pulse. The usual cooling rate was 69,000 °C/min, but 95% also survived when cooled at 10,000 °C/min. Thus, survival is far more dependent on the rate of warming than on the rate of cooling, the reason being that very high warming rates prevent or impede the recrystallization of intracellular ice. In all our experiments, the oocytes or embryos were held for 2.0 min in 1/3 EAFS before vitrification That time was chosen because Pedro (1997) found it to produce the best survival after vitrification. EAFS media are strongly hyperosmotic so that oocytes/embryos placed in them, undergo an osmotic shrink-swell pattern with time. There is an initial rapid shrinkage to a minimum volume due to water loss, followed by a much slower re-swelling due to the slow influx of the permeating solutes. Based on Pedro’s data, that minimum occurs near 2 min, and osmotic theory argues that at that point, the cells have lost 85% of their original water and very little permeating solute has entered them. The strong inference, then, is that the high subsequent survivals are a consequence of the 85% osmotic dehydration and are not due to the intracellular presence of permeating solutes. Supporting that conclusion is Jin and Mazur’s report that 77% of oocytes and 95% of 2-cell and 8-cell embryos survive vitrification when suspended in media containing only the non-permeating solutes sucrose provided they are warmed at 1 107 °C/min by a pulse from our IR laser. None survived when warmed 100 more slowly in the absence of the laser. These findings are at odds with orthodox beliefs about the causes of injury from vitrification. They could possibly open the way to the successful vitrification of important cell types that to date have been partially or fully refractory to this approach.
http://dx.doi.org/10.1016/j.cryobiol.2014.09.342
http://dx.doi.org/10.1016/j.cryobiol.2014.09.344
C-1012 Cholesterol-loaded cyclodextrin improves goat semen cryosurvival by enhancing sperm cholesterol content and osmotic tolerance V. Salmon 1, P. Leclerc 2, J. Bailey 2, 1 Centre de Recherche en Biologie de la Reproduction (CRBR), 909 Rue Monseigneur-Grandin Appt 201, Quebec G1V3X8, Canada, 2 Laval University, 2425, Rue de l’agriculture, Quebec GIV0A6, Canada. Email address: [email protected] The success of semen cryopreservation mainly resides in maintaining sperm membrane integrity and function after thawing. Cholesterol-loaded cyclodextrin (CLC) is used for in vitro incorporation of cholesterol into cells to protect them against cold temperature. We hypothesized that CLC treatment enhances sperm cholesterol content to increase its tolerance to osmotic shock and cryo-resistance, thereby improving fertility. Alpine goat sperm were treated ± 3 mg/ml CLC and lipids extracted by the Folch method, then cholesterol was quantified with Liebermann-Burchard reagent, which confirmed that CLC treatment increases the cholesterol content of fresh sperm in either PBS or skim milk extender. Sperm were then treated ± CLC in skim milk extender and cryopreserved. After thawing, sperm cholesterol dramatically fell, even in the presence of CLC, and likely explains the mechanism of ‘‘cryo-capacitation”. However, CLC treatment helped maintain a normal pre-freeze cholesterol level in the sperm after cryopreservation. Labelling sperm cholesterol with filipin confirmed this result on sperm membranes. Furthermore, fresh sperm in skim milk extender treated 3 mg/ml CLC and incubated for 20 min in hypo-, iso- and hyperosmotic PBS have increased hypoosmotic tolerance, corresponding to the beneficial effects of CLC at thawing. As expected, CLC treatment in skim milk extender improved sperm viability, motility and acrosome integrity after thawing. Furthermore, ultrasonography after artificial insemination revealed that sperm treated with CLC are 10% more fertile than control semen without CLC.
515
C-1014 High survival of mouse oocytes and preimplantation embryos after vitrification in the absence of permeating cryoprotectants and ultra-rapid warming by an IR laser pulse B. Jin, P. Mazur, The University of Tennessee, Department of Biochemistry and Cellular and Molecular Biology, Room 191N Hoskins Library, White Street, Knoxville, TN 37996-0840, United States. Email address: [email protected] In a companion presentation at this meeting and in a full paper published 3/22/14 on line in Cryobiology, we have reported that when Metaphase II mouse oocytes or 2-cell mouse embryos are suspended in EAFS vitrification media that contain only one-third the concentration of solutes as standard, over 90% survive when assessed by osmotic/morphological criteria and up to 85% survive when assessed by the functional ability to undergo IVF and/or develop in vitro to expanded blastocysts, provided that they are warmed at 10,000,000 °C/min by a powerful pulse from an IR laser. The base 0.3 EAFS medium that we used contains ethylene glycol (EG) [0.70 molal], acetamide [0.71 molal], 70,000 MW Ficoll [0.0013 molal], sucrose [0.16 molal], and PBS salts [0.15 molal]. Variants included 0, 0.16, 0.25, 0.5, and 1.0 molal sucrose, and 0.0062 molal Ficoll. Sucrose, Ficoll, and the salts cannot penetrate the cells; the EG and acetamide can readily do so, but the 2-min exposure time is too short for this to occur. As a consequence, the cells are strongly dehydrated osmotically when vitrification is initiated. This raises the question of whether permeating solutes are needed to achieve high survivals after vitrification. In the companion presentation, we argued that the most important factor aside from ultra-rapid warming was the total molality (and hence, osmolality) of the medium. In the present presentation we address the matter of survival of not only oocytes, but of 2-cell and 8-cell embryos, and morluae and blastocysts vitrified in the total absence of permeating solutes. The morphological and functional survivals of vitrified 2-cell and 8-cell embryos were 92%; the survivals of vitrified oocytes and blastocysts were above 70%. All four of these survivals were obtained with laser-induced warming at 10,000,000 °C/min. If warming was slowed 100-fold to the previous standard maximum of 100,000 °C/min, morphological and functional survivals were zero. Since no one has heretofore warmed oocytes and embryos at the ultra-high rates used here, we believe that this is the first time it has been shown that these cells can be cryopreserved in a solution that is free of any permeating compounds.
http://dx.doi.org/10.1016/j.cryobiol.2014.09.341
http://dx.doi.org/10.1016/j.cryobiol.2014.09.343
C-1013 Cryopreservation of spermic milt in the model species Ambystoma tigrinum (Tiger salamander) for application in endangered salamanders R. Marcec 1, C. Langhorne 1, C. Vance 2, A. Kouba 2, S. Willard 1, 1 Mississippi State University, Room 244, Box 9655, Dorman Hall, 32 Creelman St., MS 39762, United States, 2 The Memphis Zoo, 2000 Prentiss Place, Memphis, TN 38112, United States. Email address: [email protected]
C-1015 Implications of the consequences of laser-induced ultra-rapid warming of mouse oocytes and embryos to vitrification theory and to the successful vitrification of other cell types P. Mazur, The University of Tennessee, Department of Biochemistry and Cellular and Molecular Biology, Room 191N Hoskins Library, White Street, Knoxville, TN 379960840, United States. Email address: [email protected]
In the face of the amphibian extinction crisis, captive assurance colonies have been established to preserve genetic diversity. Sadly, many captive assurance colonies fail due to reproductive cues which are not entirely understood. In addition, the majority of amphibian conservation and genome banking research has focused on anurans (frogs/toads), despite the fact that caudates (salamanders/newts) face a larger threat of extinction. Therefore, it is critical that assisted reproductive technologies, such as gamete cryopreservation and artificial fertilization, be developed as conservation tools for application in genetic management of threatened caudates. It was hypothesized that a modified anuran sperm freezing protocol could be successfully used in cryopreservation of Ambystoma tigrinum (tiger salamander) sperm as a caudate model. Spermiation in male tiger salamanders was hormonally induced via injection with hCG, LHRH, or a combination of these two hormones. Average spermic milt concentrations were 2.75 107(±7.2 106)/mL. Average total motility upon collection of fresh milt was 53.6% (±17.6%). After collection and initial analysis, fresh milt samples were diluted 1:1 in chilled cryoprotectant treatment solutions. They were then frozen in 0.25 mL French straws using a stepwise slowrate freezing process. Upon thawing, milt suspensions were diluted 1:10 with a 10% Holtfreter’s solution in order to activate the sperm for post thaw analysis. Frozen-thawed sperm in the 5% Me2SO treatment group had an average total motility of 19.1% (±15.8%) and sperm in the 5% Me2SO with 0.5% BSA treatment group had an average total motility of 21.75% (±14.8%). Early trials showed that caudate sperm are not susceptible to toxicity from several cryoprotective media. Moreover, initial fertilization trials indicate that frozen-thawed caudate sperm are capable of producing early cleavage stage embryos. Optimizing cryopreservation protocols for salamander sperm is an important step in building a global genetic resource bank for endangered caudates.
Jin, Kleinhans, and Mazur have reported in this meeting that up to 100% of oocytes and 2-cell embryos survive vitrification in a 3-fold dilution of EAFS medium if warmed at 10,000,000 °C/min by an IR laser pulse. The usual cooling rate was 69,000 °C/min, but 95% also survived when cooled at 10,000 °C/min. Thus, survival is far more dependent on the rate of warming than on the rate of cooling, the reason being that very high warming rates prevent or impede the recrystallization of intracellular ice. In all our experiments, the oocytes or embryos were held for 2.0 min in 1/3 EAFS before vitrification That time was chosen because Pedro (1997) found it to produce the best survival after vitrification. EAFS media are strongly hyperosmotic so that oocytes/embryos placed in them, undergo an osmotic shrink-swell pattern with time. There is an initial rapid shrinkage to a minimum volume due to water loss, followed by a much slower re-swelling due to the slow influx of the permeating solutes. Based on Pedro’s data, that minimum occurs near 2 min, and osmotic theory argues that at that point, the cells have lost 85% of their original water and very little permeating solute has entered them. The strong inference, then, is that the high subsequent survivals are a consequence of the 85% osmotic dehydration and are not due to the intracellular presence of permeating solutes. Supporting that conclusion is Jin and Mazur’s report that 77% of oocytes and 95% of 2-cell and 8-cell embryos survive vitrification when suspended in media containing only the non-permeating solutes sucrose provided they are warmed at 1 107 °C/min by a pulse from our IR laser. None survived when warmed 100 more slowly in the absence of the laser. These findings are at odds with orthodox beliefs about the causes of injury from vitrification. They could possibly open the way to the successful vitrification of important cell types that to date have been partially or fully refractory to this approach.
http://dx.doi.org/10.1016/j.cryobiol.2014.09.342
http://dx.doi.org/10.1016/j.cryobiol.2014.09.344