We would like to thank Dr. Julie Gordon and Dr. Nancy Manley for their helpful advice with the culture technique. This work has been supported by the Children&#8217;s Glaucoma Foundation and Sharon-Stewart Aniridia Research Trust.

Mouse embryo culture:
All experimental procedures were conducted in strict accordance with National Institutes of Health guidelines following protocol # A2010 07-119, which was reviewed and approved by the University of Georgia Institutional Animal Care and Use Committee, which maintains continued regulatory oversight.
1. Preparation of Culture Media
<ol>
	<li>Prepare culture medium using commercially available stem cell media and supplements in the following amounts...

<ol>
	<li>Behesti, H., Holt, J. K., Sowden, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+level+of+BMP4+signaling+is+critical+for+the+regulation+of+distinct+T-box+gene+expression+domains+and+growth+along+the+dorso-ventral+axis+of+the+optic+cup.">The level of BMP4 signaling is critical for the regulation of distinct T-box gene expression domains and growth along the dorso-ventral axis of the optic cup.</a> BMC Dev. Biol. 6, 62 (2006).</li><li>Gray, J., Ross, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neural+tube+closure+in+mouse+whole+embryo+culture.">Neural tube closure in mouse whole embryo culture.</a> J. Vis. Exp. , (2011).</li><li>Tam, P. 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Natl. Acad. Sci. U.S.A. 102, 3296-3300 (2005).</li><li>Sadler, T. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Culture+of+early+somite+mouse+embryos+during+organogenesis.">Culture of early somite mouse embryos during organogenesis.</a> J. Embryol. Exp. Morphol. 49, 17-25 (1979).</li><li>Kitchin, K. T., Ebron, M. 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R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serum-Free+Culture+of+Mid-gestation+Mouse+Embryos:+A+Tool+for+the+Study+of+Endoderm-Derived+Organs.">Serum-Free Culture of Mid-gestation Mouse Embryos: A Tool for the Study of Endoderm-Derived Organs.</a> Methods Mol. Biol. 1092, 183-194 (2014).</li><li>New, D. A., Cockroft, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+rotating+bottle+culture+method+with+continuous+replacement+of+the+gas+phase.">A rotating bottle culture method with continuous replacement of the gas phase.</a> Experientia. 35, 138-140 (1979).</li><li>Cockroft, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+in+culture+of+rat+foetuses+explanted+at+12.5+and+13.5+days+of+gestation.">Development in culture of rat foetuses explanted at 12.5 and 13.5 days of gestation.</a> J. Embryol. Exp. Morphol. 29, 473-483 (1973).</li><li>Zeeb, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pharmacological+manipulation+of+blood+and+lymphatic+vascularization+in+ex+vivo-cultured+mouse+embryos.">Pharmacological manipulation of blood and lymphatic vascularization in ex vivo-cultured mouse embryos.</a> Nat. Protoc. 7, 1970-1982 (2012).</li><li>Wawersik, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=BMP7+acts+in+murine+lens+placode+development.">BMP7 acts in murine lens placode development.</a> Dev. Biol. 207, 176-188 (1999).</li><li>Thut, C. J., Rountree, R. B., Hwa, M., Kingsley, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+large-scale+in+situ+screen+provides+molecular+evidence+for+the+induction+of+eye+anterior+segment+structures+by+the+developing+lens.">A large-scale in situ screen provides molecular evidence for the induction of eye anterior segment structures by the developing lens.</a> Dev. Biol. 231, 63-76 (2001).</li><li>Greenfield, J. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estrogen+lowers+Alzheimer+beta-amyloid+generation+by+stimulating+trans-Golgi+network+vesicle+biogenesis.">Estrogen lowers Alzheimer beta-amyloid generation by stimulating trans-Golgi network vesicle biogenesis.</a> J. Biol. Chem. 277, 12128-12136 (2002).</li><li>Cheng, J., Dutra, A., Takesono, A., Garrett-Beal, L., Schwartzberg, P. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+generation+of+C57BL/6J+mouse+embryonic+stem+cells+in+a+defined+serum-free+media.">Improved generation of C57BL/6J mouse embryonic stem cells in a defined serum-free media.</a> Genesis. 39, 100-104 (2004).</li><li>Kim, J. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+reprogramming+of+human+neural+stem+cells+by+OCT4.">Direct reprogramming of human neural stem cells by OCT4.</a> Nature. 461, 649-643 (2009).</li><li>Totonchi, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Feeder-+and+serum-free+establishment+and+expansion+of+human+induced+pluripotent+stem+cells.">Feeder- and serum-free establishment and expansion of human induced pluripotent stem cells.</a> Int. J. Dev. Biol. 54, 877-886 (2010).</li></ol>

We do not have any competing financial interests.

Mid-gestation stage mouse embryos were cultured in a serum-free culture media in an atmosphere of 95% O2 / 5% CO2 in a rolling bottle culture apparatus at 37 &#176;&#8203;C. Embryo development ex utero was critically dependent on multiple factors at each step during the procedure from the time the uterus is isolated from the euthanized mice to the completion of the culture (Figure 1). The most important factor that influenced the development was the time taken to start the ...

In vitro culture methods utilizing whole embryos are well suited to study signaling mechanisms involved in embryonic organogenesis that are otherwise difficult to access in utero. Whole embryos provide the tissue integrity and support appropriate for the tissue interactions that are crucial for timely occurrence of signaling mechanisms essential for different cellular processes during organogenesis. While whole embryo cultures provide a platform for a plethora of applications such as transplantation studies, genetic and tissue manipulations, bead implantation studies, toxicological studies, etc., currently utilized embryo culture systems are mainly dependent on serum for proper growth and maintenance of the embryos in the culture1-9.
Serum has been utilized as one of the major components ranging from 10-100% of the culture media6-8,10,11.&#160; However, the composition of serum is not well defined and can differ from animal to animal and each time the serum is collected. While laboratory preparation of serum is time consuming and involves stringent procedures, serum procured commercially exhibits considerable variability among different lots and raises experimental costs. Added to these, the serum may contain unknown factors such as growth factors, hormones, or other proteins, which can potentially affect the outcome of certain experiments, especially those that involve the study of signaling molecules important in tissue interactions. Studies have shown that addition of serum to culture can potentially alter the intracellular levels of certain signaling molecules such as cyclic adenosine monophosphate (cAMP) and proteins involved in mitogenic signaling and phosphoinositide 3 (PI 3)-kinase signaling pathways12-14. Contrary to these, a serum-free culture system provides the advantages of antigen free environment, abstinence from biologically active enzymes that can alter the cellular processes and enables consistency among experiments.
In the present study, we utilized a serum-free culture medium prepared from commercially available stem cell media supplements to culture mid-gestation stage whole embryos in an atmosphere of 95% O2 / 5% CO2 in a rolling bottle culture apparatus at 37 &#176;&#8203;C15,16.&#160; Mouse embryos cultured for 16 to 40 hr&#160;under these defined conditions exhibited progression in morphological development of overall embryonic body and different structures such as the heart, limbs, brain and eyes indicating appropriate levels of cellular proliferation, migration, differentiation and tissue interactions. Molecular analysis of the embryonic development in the culture for one of the complex organ systems such as the eye revealed the ocular development to be consistent with that observed in ocular tissue in embryos developing in utero (Kalaskar and Lauderdale, in preparation). Thus we show that mouse embryos cultured at mid-gestation stage, exhibit progressive growth and morphological development comparable to that observed in embryos developing in utero.

<table border="0" cellpadding="0" cellspacing="0" width="634">
	<tbody>
		<tr>
			<td>KnockOut DMEM</td>
			<td>Invitrogen</td>
			<td>10829-018</td>
			<td></td>
		</tr>
		<tr>
			<td>KnockOut Serum Replacement</td>
			<td>Invitrogen</td>
			<td>10828-028</td>
			<td></td>
		</tr>
		<tr>
			<td>N-2 Supplement</td>
			<td>Invitrogen</td>
			<td>17502-048</td>
			<td>Stock: 100x</td>
		</tr>
		<tr>
			<td>Albumin, from Bovine Serum</td>
			<td>Sigma</td>
			<td>A9418-50G</td>
			<td>Stock: 100%</td>
		</tr>
		<tr>
			<td>Antibiotic - Antimycotic Solution</td>
			<td>Cellgro</td>
			<td>30-004-Cl</td>
			<td>Stock: Penicillin (10000 IU/ml); Streptomycin (10000 &#181;g/ml; Amphotericin (250&#181;g/ml)&#160;</td>
		</tr>
		<tr>
			<td>DMEM&#160;&#160;</td>
			<td>Cellgro</td>
			<td>15-013-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Precision Incubator Unit</td>
			<td>B.T.C. Engineering Milton Cambridge England</td>
			<td>Id.No. 840-374</td>
			<td></td>
		</tr>
		<tr>
			<td>Glass Bottles for Rotating Unit</td>
			<td>B.T.C. Engineering</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Silicone Rubber Cork</td>
			<td>B.T.C. Engineering</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>95% O2/5% CO2 Cylinder</td>
			<td>AirGas Inc.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Stemi SV11 Apo Dissecting Microscope</td>
			<td>Zeiss</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Stemi SV6 Microscope</td>
			<td>Zeiss</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>CO2 Water Jacketed Incubator</td>
			<td>Forma Scientific</td>
			<td>Model: 3110</td>
			<td></td>
		</tr>
		<tr>
			<td>Culture Hood</td>
			<td>Nuaire Biological Safety Cabinets Class II TypeA2</td>
			<td>Model: Nu-425-600</td>
			<td></td>
		</tr>
		<tr>
			<td>Water Bath</td>
			<td>Fisher Scientific</td>
			<td>IsoTemp205</td>
			<td></td>
		</tr>
		<tr>
			<td>Weigh Balance</td>
			<td>Mettler Toledo&#160;</td>
			<td>AG285</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge Tube &#8211; 50ml</td>
			<td>Corning</td>
			<td>430291</td>
			<td></td>
		</tr>
		<tr>
			<td>Light Operating Scissors</td>
			<td>Roboz</td>
			<td>RS-6702</td>
			<td></td>
		</tr>
		<tr>
			<td>Operating Sharp-Blunt Scissors&#160;</td>
			<td>Roboz</td>
			<td>RS-6812</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro Dissecting Forceps &#8211; 4&#8221;</td>
			<td>Roboz</td>
			<td>RS-5211</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro Dissecting Forceps - Hudson (cWALD) &#8211; 4-3/4&#8221;</td>
			<td>Roboz</td>
			<td>RS-5237</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro Dissecting Tweezers (5/45)</td>
			<td>Roboz</td>
			<td>RS-5005</td>
			<td>Modified - Sharp ends were made blunt</td>
		</tr>
		<tr>
			<td>Micro Dissecting Tweezers (5)</td>
			<td>Roboz</td>
			<td>RS-5060</td>
			<td>Modified - Sharp ends were made blunt</td>
		</tr>
		<tr>
			<td>Micro Dissecting Tweezers (55)</td>
			<td>Roboz</td>
			<td>RS-5063</td>
			<td>Modified - Sharp ends were made blunt</td>
		</tr>
		<tr>
			<td>Instrument Tray</td>
			<td>Roboz</td>
			<td>RT-1401S</td>
			<td></td>
		</tr>
		<tr>
			<td>Instrument Tray Lid</td>
			<td>Roboz</td>
			<td>RT-1401L</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri Dish-100mm</td>
			<td>Fisher Scientific</td>
			<td>087571Z</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri Dish-60mm</td>
			<td>Fisher Scientific</td>
			<td>0875713A</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri Dish-35mm</td>
			<td>Fisher Scientific</td>
			<td>0875711YZ</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter System ( 0.22um Cellulose Acetate)-150ml</td>
			<td>Corning</td>
			<td>431153</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter System ( 0.22um Cellulose Acetate)-250ml</td>
			<td>Corning</td>
			<td>430756</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter System ( 0.22um Cellulose Acetate)-500ml</td>
			<td>Corning</td>
			<td>430758</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipet-aid Pipetter</td>
			<td>Drummond Scientific Co.</td>
			<td>D57849</td>
			<td></td>
		</tr>
		<tr>
			<td>Serological Pipette-10ml</td>
			<td>VWR</td>
			<td>89130-898</td>
			<td></td>
		</tr>
		<tr>
			<td>Disposable Serological Pipette-25ml</td>
			<td>Corning</td>
			<td>4251</td>
			<td></td>
		</tr>
		<tr>
			<td>Transfer Pipette - 7.7ml</td>
			<td>Thermo Scientific</td>
			<td>202-20S</td>
			<td></td>
		</tr>
	</tbody>
</table>

mouse embryonic development in a serum-free whole embryo culture system

Mid-gestation stage mouse embryos were cultured utilizing a serum-free culture medium prepared from commercially available stem cell media supplements in an oxygenated rolling bottle culture system. Mouse embryos at E10.5 were carefully isolated from the uterus with intact yolk sac and in a process involving precise surgical maneuver the embryos were gently exteriorized from the yolk sac while maintaining the vascular continuity of the embryo with the yolk sac. Compared to embryos prepared with intact yolk sac or with the yolk sac removed, these embryos exhibited superior survival rate and developmental progression when cultured under similar conditions. We show that these mouse embryos, when cultured in a defined medium in an atmosphere of 95% O2 / 5% CO2 in a rolling bottle culture apparatus at 37 &#176;&#8203;C for 16-40 hr, exhibit morphological growth and development comparable to the embryos developing in utero. We believe this method will be useful for investigators needing to utilize whole embryo culture to study signaling interactions important in embryonic organogenesis.

Development of mouse embryos ex utero depends on multiple factors starting from the time the uterus is isolated from the body to the time the embryos are cultured. As depicted in Figure 1, the procedure involves a series of steps including, separation of the gravid uterus from the body (Figure 1A), isolation of the embryos with intact yolk sac (Figure 1B), exteriorization of the embryos from the yolk sac (Figure 1C) and culturing the embryos in ...

Watch this Scientific Journal Video about Mouse Embryonic Development in a Serum-free Whole Embryo Culture System at JoVE.com

Mouse Embryonic Development in a Serum-free Whole Embryo Culture System

Serum utilized in embryo cultures contains unknown components that can affect the outcome of experiments especially in studies involving signaling interactions. Here we utilized a serum-free oxygenated culture system and show that mid-gestation mouse embryos cultured for 16-40 hr&#160;exhibit morphological development comparable to embryos developing in utero.

Mid-gestation stage mouse embryos were cultured utilizing a serum-free culture medium prepared from commercially available stem cell media supplements in ...

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Biology

25.5K Görüntüleme.  University of Georgia.  Embriyo kültürlerinde kullanılan serum, özellikle sinyalizasyon etkileşimler içeren çalışmalarda deney sonucunu etkileyebilecek bilinmeyen bileşenleri içerir. Burada bir serum içermeyen kültür sistemi kullanılan oksijenli ve 16-40 saat süre ile kültüre orta gebelik fare embriyo utero gelişen embriyo benzer morfolojik gelişimini gösteren göstermektedir. 