The authors thank UT AgResearch and the Department of Animal Science for supporting and optimizing this protocol. This work was funded by USDA grant.

<ol>
	<li>Fryar, C. D., Carroll, M. D., Ogden, C. 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> Prevalence of overweight, obesity, and severe obesity among children and adolescents aged 2-19 years: United States, 1963-1965 through 2015-2016. , (2018).</li><li>Siegel, P. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evolution+of+the+modern+broiler+and+feed+efficiency.">Evolution of the modern broiler and feed efficiency.</a> Annual Review of Animal Biosciences. 2 (1), 375-385 (2014).</li><li>Zuidhof, M. J., Schneider, B. L., Carney, V. L., Korver, D., Robinson, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Growth,+efficiency,+and+yield+of+commercial+broilers+from+1957,+1978,+and+2005.">Growth, efficiency, and yield of commercial broilers from 1957, 1978, and 2005.</a> Poultry Science. 93 (12), 2970-2982 (2014).</li><li>Poulos, S. P., Dodson, M. V., Hausman, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+line+models+for+differentiation:+preadipocytes+and+adipocytes.">Cell line models for differentiation: preadipocytes and adipocytes.</a> Experimental Biology and Medicine. 235 (10), 1185-1193 (2010).</li><li>Vilaboa, S. D. -. A., Navarro-Palou, M., Llull, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Age+influence+on+stromal+vascular+fraction+cell+yield+obtained+from+human+lipoaspirates.">Age influence on stromal vascular fraction cell yield obtained from human lipoaspirates.</a> Cytotherapy. 16 (8), 1092-1097 (2014).</li><li>Speake, B. K., Noble, R. C., McCartney, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue-specific+changes+in+lipid+composition+and+lipoprotein+lipase+activity+during+the+development+of+the+chick+embryo.">Tissue-specific changes in lipid composition and lipoprotein lipase activity during the development of the chick embryo.</a> Biochimica et Biophysica Acta (BBA)-Lipids and Lipid Metabolism. 1165 (3), 263-270 (1993).</li><li>Chen, P., Suh, Y., Choi, Y. 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I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+morphology,+development,+and+function+of+blood+cells+in+nonmammalian+vertebrates.">Comparative morphology, development, and function of blood cells in nonmammalian vertebrates.</a> Journal of Exotic Pet Medicine. 18 (2), 87-97 (2009).</li><li>. Corning Cell Counter Demo Video Available from: <a target="_blank" href="https://www.youtube.com/watch?v=JWjckEHO6Wg">https://www.youtube.com/watch?v=JWjckEHO6Wg</a> (2022)</li><li>Nema, R., Khare, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+animal+cell+culture:+Advance+technology+for+modern+research.">An animal cell culture: Advance technology for modern research.</a> Advances in Bioscience and Biotechnology. 3 (3), 219-226 (2012).</li><li>Regassa, A., Kim, W. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+oleic+acid+and+chicken+serum+on+the+expression+of+adipogenic+transcription+factors+and+adipogenic+differentiation+in+hen+preadipocytes.">Effects of oleic acid and chicken serum on the expression of adipogenic transcription factors and adipogenic differentiation in hen preadipocytes.</a> Cell Biology International. 37 (9), 961-971 (2013).</li><li>Temkin, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+crude+oil/dispersant+mixture+and+dispersant+components+on+PPAR+&#947;+activity+in+vitro+and+in+vivo:+identification+of+dioctyl+sodium+sulfosuccinate+(DOSS;+CAS#+577-11-7)+as+a+probable+obesogen.">Effects of crude oil/dispersant mixture and dispersant components on PPAR &#947; activity in vitro and in vivo: identification of dioctyl sodium sulfosuccinate (DOSS; CAS# 577-11-7) as a probable obesogen.</a> Environmental Health Perspectives. 124, 112-119 (2016).</li><li>Hausman, D. B., Park, H. J., Hausman, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Adipose Tissue Protocols. , 201-219 (2008).</li><li>Lee, M. J., Wu, Y., Fried, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+modified+protocol+to+maximize+differentiation+of+human+preadipocytes+and+improve+metabolic+phenotypes.">A modified protocol to maximize differentiation of human preadipocytes and improve metabolic phenotypes.</a> Obesity. 20 (12), 2334-2340 (2012).</li><li>Church, C. D., Berry, R., Rodeheffer, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+study+of+adipocyte+precursors.">Isolation and study of adipocyte precursors.</a> Methods in Enzymology. 537, 31-46 (2014).</li><li>Akbar, N., Pinnick, K. E., Paget, D., Choudhury, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+characterization+of+human+adipocyte-derived+extracellular+vesicles+using+filtration+and+ultracentrifugation.">Isolation and characterization of human adipocyte-derived extracellular vesicles using filtration and ultracentrifugation.</a> Journal of Visualized Experiments. (170), e61979 (2021).</li><li>Perlman, D., Giuffre, N. A., Brindle, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+Fungizone+in+control+of+fungi+and+yeasts+in+tissue+culture.">Use of Fungizone in control of fungi and yeasts in tissue culture.</a> Proceedings of the Society for Experimental Biology and Medicine. 106 (4), 880-883 (1961).</li><li>Kuhlmann, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+prophylactic+use+of+antibiotics+in+cell+culture.">The prophylactic use of antibiotics in cell culture.</a> Cytotechnology. 19 (2), 95-105 (1995).</li><li>Yang, X., 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=Black+swimming+dots+in+cell+culture:+the+identity,+detection+method+and+judging+criteria.">Black swimming dots in cell culture: the identity, detection method and judging criteria.</a> bioRxiv. , 366906 (2018).</li><li>Freshney, R. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Culture of animal cells: a manual of basic technique and specialized applications. , 163-186 (2015).</li></ol>

The authors have nothing to disclose.

Although several well-described protocols have reported the isolation of preadipocytes14,15,16,17, isolation for embryonic preadipocytes has been optimized, which can be used for functional analyses of early life fat growth and development in broiler chicks. This protocol yields high viability embryonic adipocyte progenitors with high differentiation potential. Moreover, the presented procedure for isolating preadipocytes is not limited to embryos but can be used in post-hatch chicks. However, it has been optimized for use with E16 embryos, and yields from chicks after hatch are considerably lower (Table 1), likely due to increases in the relative amount of connective tissue as chicks grow rapidly.
The success of cell isolation is ultimately evaluated by observing the shape and number of attached cells (Figure 3A). Low cell number or damaged cells can be observed when the tissue fractions are digested too long, especially when tissue dissociation progresses for more than 1.5 h (Figure 3E). Therefore, it is recommended that 1.5 h of digestion is not exceeded. On the other hand, if the tissue fragment remains clearly after an hour of digestion, the digestive time or the amount should be increased. The obtained adipose tissue amount also might be varied depending on the genetic strain of the chicken. If this protocol is used to isolate cells of other ages or species, both the amount of collagenase and digestion time will likely need to be modified.
A common limitation of primary cell culture is that isolated cells begin to lose adipogenic potential after several passages in culture; thus, it is important to induce differentiation within a few days of isolation to ensure the embryonic preadipocytes do not lose their adipogenic ability. Adipogenic precursors of embryos readily differentiate into mature adipocytes in the media formulation described above, without the need for confluence or hormonal induction. The cells up to passage 4 (10-14 days) are easily differentiated within 48 h of inducement (Figure 3D).
Controlling cell contamination in primary cell culture is another challenge, where fungal contamination is the most common. The use of Amphotericin B, as described, is generally effective at preventing fungal growth18,19. It can be included at low concentrations in the culture media with no noticeable effects on viability or adipogenic potential. Unidentifiable microbial contaminants have been observed in the form of black swimming dots appearing a few days after cell isolation (Figure 3F). These adversely affected cell growth and were impossible to remove once this infection occured20. Whether these contaminants were an unknown microbial species found in or on eggs or arose from another source is unknown. This protocol attempts to minimize the risk of contamination by extracting embryos aseptically from the egg21. Using a heat-based instrument sterilizer in the hood during dissection also helps to minimize the potential for contamination, especially when multiple embryos are dissected.
One consideration in the process is decreased cell adhesion to tissue culture plate during differentiation, resulting from physical changes as cells form and expand lipid droplets. Although contained within the cells, lipid droplets are buoyant and, when large, appear to act as balloons that tend to promote cells lifting from the surface. Thus, care should be taken in handling preadipocytes while inducing differentiation, and particularly when adipogenesis is assessed. While the protocol presented here does not modify the culture surface, cell adhesion can be enhanced when plating cells on dishes coated with 2% gelatin. It is also important to confirm the pH of wash solutions to be 7.4 and to use pre-warmed PBS solution when washing cells and mixing with the DNA stain to reduce cold stress.
Using multiple embryos, sufficient numbers of cells can be isolated to yield experimental replicates without the need for multiple passages, expansion and the risk of cells losing their adipogenic potential. RNA can be easily isolated from both pre- and differentiated chick embryo adipocytes isolated using phenol- or membrane-based commercial methods for gene expression studies. Sufficient RNA can be obtained from a single well of a six-well plate for use in cDNA synthesis and follow-on qPCR or RNAseq.
In summary, the accessibility of adipose depots in the chick embryo to isolate a cell model is highly relevant for both poultry and humans. This protocol is relatively simple to perform, and it yields a high percentage of viable cells that can be readily induced to undergo adipogenic differentiation in vitro. Fertilized chicken eggs can be obtained from various commercial sources for minimal cost, making these cells a readily available model for practical use.

Obesity is a global health threat to both adults and children. Children who are overweight or obese are approximately five times more likely to be obese as adults, placing them at significantly increased risk for cardiovascular disease, diabetes, and many other comorbidities. About 13.4% of US children aged 2-5 have obesity1, illustrating that the tendency to accumulate excess body fat can be set in motion very early in life. For very different reasons, the accumulation of excess adipose tissue is a concern for broiler (meat-type) chickens. Modern broilers are incredibly efficient but still accumulate more lipid than is physiologically necessary2,3. This tendency begins soon after hatch and effectively wastes feed, the most expensive production component, by allocating it away from muscle growth. Therefore, for both children and broiler chickens, albeit for very different reasons, there is a need to understand factors that influence adipose tissue development and identify ways to limit adipose expansion early in life.
Adipocytes form from preadipocytes, adipose tissue-derived stem cells that undergo differentiation to develop mature, lipid-storing fat cells. Accordingly, preadipocytes in vitro are a valuable experimental model for obesity studies. These cells, isolated from the stromal vascular fraction of adipose depots, can provide a fundamental understanding of molecular pathways controlling adipocyte differentiation and metabolism4,5. Chick embryos are a favorable experimental model in developmental studies because culturing eggs on the desired schedule makes experimental manipulation easier, as it enables obtaining embryos without the mother's sacrifice to observe a series of developmental stages of embryos. Moreover, complicated surgical procedures and lengthy periods of time are not required to obtain embryos relative to larger animal models. Therefore, the chick embryo presents an opportunity to obtain preadipocytes from the earliest stages of adipose tissue development. Subcutaneous adipose tissue becomes visible in the chick around embryonic day 12 (E12) as a clearly defined depot located around the thigh. This depot is enriched in highly proliferative preadipocytes that actively undergo differentiation under developmental cues to form mature adipocytes6,7. The process of adipogenic differentiation is comparable between chickens and humans. Therefore, preadipocytes isolated from chick embryos can be used as a dual-purpose model for studies relevant to humans and poultry. However, the yield of preadipocytes declines with aging as cells grows into mature adipocytes5.
The present protocol optimizes the isolation of preadipocytes from adipose tissue during the stage (E16-E18) at which adipogenic differentiation and adipocyte hypertrophy are at their peak in broiler chick embryos8. This procedure can assess the effects of factors to which the developing embryo is exposed in ovo, such as the hen diet, on adipocyte development and adipogenic potential ex vivo. It can also test the impact of various manipulations (e.g., hypoxia, nutrient additions, pharmacological agonists, and antagonists) on adipogenesis or the various 'omes (e.g., transcriptome, metabolome, methylome) of adipocyte progenitors. As a representation of the earliest stage of adipose formation, cells obtained using this protocol are valuable models for studies relevant to poultry and humans.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1 mL Pipette</td>
			<td>Eppendorf</td>
			<td>Z683825</td>
			<td>Single Channel Pipette, 100 - 1000 &#181;L</td>
		</tr>
		<tr>
			<td>1 mL Pipette Tip</td>
			<td>Fisher Scientific</td>
			<td>02-707-402</td>
			<td></td>
		</tr>
		<tr>
			<td>100% Isopropanol</td>
			<td>Fisher Scientific</td>
			<td>A426P4</td>
			<td></td>
		</tr>
		<tr>
			<td>1x PBS</td>
			<td>Gibco</td>
			<td>10010023</td>
			<td></td>
		</tr>
		<tr>
			<td>25 mL Flask</td>
			<td>Pyrex</td>
			<td>4980-25</td>
			<td></td>
		</tr>
		<tr>
			<td>37% Formaldehyde</td>
			<td>Fisher Scientific</td>
			<td>F75P-1GAL</td>
			<td></td>
		</tr>
		<tr>
			<td>6-Well Plate</td>
			<td>Falcon</td>
			<td>353046</td>
			<td>Tissue Culture-treated</td>
		</tr>
		<tr>
			<td>96-Well Assay Plate</td>
			<td>Costar</td>
			<td>3632</td>
			<td></td>
		</tr>
		<tr>
			<td>96-Well Plate, Black Bottom</td>
			<td>Costar</td>
			<td>3603</td>
			<td>Tissue Culture-treated</td>
		</tr>
		<tr>
			<td>AdipoRed</td>
			<td>Lonza</td>
			<td>PT-7009</td>
			<td></td>
		</tr>
		<tr>
			<td>Amphotericin B</td>
			<td>Gibco</td>
			<td>15290026</td>
			<td></td>
		</tr>
		<tr>
			<td>Bench Top Wiper (Kimtechwiper)</td>
			<td>Kimberly-Clark</td>
			<td>34155</td>
			<td></td>
		</tr>
		<tr>
			<td>Betadine</td>
			<td>Up &#38; Up</td>
			<td>NDC 1167300334</td>
			<td>20% Working Solution</td>
		</tr>
		<tr>
			<td>Cell Counter</td>
			<td>Corning</td>
			<td>6749</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell Strainer, 40 &#181;m</td>
			<td>SPL</td>
			<td>93040</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifugaton</td>
			<td>Eppendorf</td>
			<td>5702</td>
			<td></td>
		</tr>
		<tr>
			<td>Chicken Serum</td>
			<td>Gibco</td>
			<td>16110082</td>
			<td></td>
		</tr>
		<tr>
			<td>Conical Centrifuge Tubes, 15 mL</td>
			<td>VWR</td>
			<td>10025-690</td>
			<td></td>
		</tr>
		<tr>
			<td>Conical Centrifuge Tubes, 50 mL</td>
			<td>Falcon</td>
			<td>352098</td>
			<td></td>
		</tr>
		<tr>
			<td>Cryovial</td>
			<td>Nunc</td>
			<td>343958</td>
			<td></td>
		</tr>
		<tr>
			<td>Curved Forceps, 100 mm</td>
			<td>Roboz Surgical</td>
			<td>RS-5137</td>
			<td></td>
		</tr>
		<tr>
			<td>Curved Surgical Scissors, 115 mm</td>
			<td>Roboz Surgical</td>
			<td>RS-6839</td>
			<td></td>
		</tr>
		<tr>
			<td>Distilled Water</td>
			<td>Millipore</td>
			<td>SYNSV0000</td>
			<td>Despensed as needed</td>
		</tr>
		<tr>
			<td>DMEM/F12</td>
			<td>HyClone</td>
			<td>SH30023.01</td>
			<td></td>
		</tr>
		<tr>
			<td>DMSO</td>
			<td>Sigma</td>
			<td>D2650</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>Decon Labs</td>
			<td>2701</td>
			<td>70% Working Solution</td>
		</tr>
		<tr>
			<td>Fetal Bovine Serum (FBS)</td>
			<td>Gibco</td>
			<td>10437028</td>
			<td></td>
		</tr>
		<tr>
			<td>Fluorescent Microscope</td>
			<td>Evos</td>
			<td>M7000</td>
			<td></td>
		</tr>
		<tr>
			<td>Fluorescent Plate Reader</td>
			<td>Biotek</td>
			<td>Synergy H1</td>
			<td></td>
		</tr>
		<tr>
			<td>Foil</td>
			<td>Reynolds</td>
			<td></td>
			<td>Reynolds Wrap Heavy Duty Aluminum Foil, 125 SQ. FT.</td>
		</tr>
		<tr>
			<td>Freezing Container</td>
			<td>Thermo Scientific</td>
			<td>5100-0001</td>
			<td></td>
		</tr>
		<tr>
			<td>Gelatin</td>
			<td>Millipore</td>
			<td>4055</td>
			<td>2% Working Solution</td>
		</tr>
		<tr>
			<td>Hematocytometer (Counting Chamber)</td>
			<td>Corning</td>
			<td>480200</td>
			<td>0.1 mm deep</td>
		</tr>
		<tr>
			<td>Incubator</td>
			<td>Fisher Scientific</td>
			<td>6845</td>
			<td></td>
		</tr>
		<tr>
			<td>Instrument Sterilizer</td>
			<td>VWR</td>
			<td>B1205</td>
			<td></td>
		</tr>
		<tr>
			<td>Linoleic Acid-Oleic Acid-Albumin</td>
			<td>Sigma</td>
			<td>L9655</td>
			<td>1x Working Solution</td>
		</tr>
		<tr>
			<td>Microscope</td>
			<td>Evos</td>
			<td>AMEX1000</td>
			<td></td>
		</tr>
		<tr>
			<td>Multi-Channel Pipette</td>
			<td>Thermo Scientific</td>
			<td>4661070</td>
			<td>12-Channel Pipetters, 30 - 300 &#181;L</td>
		</tr>
		<tr>
			<td>Na2HPO4</td>
			<td>Sigma</td>
			<td>S-7907</td>
			<td></td>
		</tr>
		<tr>
			<td>NaH2PO4</td>
			<td>Sigma</td>
			<td>S-3139</td>
			<td></td>
		</tr>
		<tr>
			<td>NucBlue</td>
			<td>Invitrogen</td>
			<td>R37605</td>
			<td></td>
		</tr>
		<tr>
			<td>Oil Red O</td>
			<td>Sigma</td>
			<td>O-0625</td>
			<td></td>
		</tr>
		<tr>
			<td>Orbital Shaker</td>
			<td>IKA</td>
			<td>KS130BS1</td>
			<td></td>
		</tr>
		<tr>
			<td>Paper Towel</td>
			<td>Tork</td>
			<td>RK8002</td>
			<td></td>
		</tr>
		<tr>
			<td>Parafilm</td>
			<td>Parafilm M</td>
			<td>PM996</td>
			<td></td>
		</tr>
		<tr>
			<td>Penicillin/Steptomycin (P/S)</td>
			<td>Gibco</td>
			<td>15140122</td>
			<td>1x Working Solution</td>
		</tr>
		<tr>
			<td>Petri dishes, 100 mm</td>
			<td>Falcon</td>
			<td>351029</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dishes, 60 mm</td>
			<td>Falcon</td>
			<td>351007</td>
			<td></td>
		</tr>
		<tr>
			<td>Plate Shaker</td>
			<td>VWR</td>
			<td>200</td>
			<td></td>
		</tr>
		<tr>
			<td>RBC Lysis Buffer</td>
			<td>Roche</td>
			<td>11814389001</td>
			<td></td>
		</tr>
		<tr>
			<td>Reagent Reservior</td>
			<td>VWR</td>
			<td>89094-680</td>
			<td></td>
		</tr>
		<tr>
			<td>Small Beaker, 100 mL</td>
			<td>Pyrex</td>
			<td>1000-100</td>
			<td></td>
		</tr>
		<tr>
			<td>Spectrophotometer Plate Reader</td>
			<td>Biotek</td>
			<td>Synergy H1</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile Gauze</td>
			<td>McKesson</td>
			<td>762703</td>
			<td></td>
		</tr>
		<tr>
			<td>Straight Forceps, 120 mm</td>
			<td>Roboz Surgical</td>
			<td>RS-4960</td>
			<td></td>
		</tr>
		<tr>
			<td>Straight Scissors, 140 mm</td>
			<td>Roboz Surgical</td>
			<td>RS-6762</td>
			<td></td>
		</tr>
		<tr>
			<td>T-25 Flask</td>
			<td>Corning</td>
			<td>430639</td>
			<td>Tissue Culture-treated</td>
		</tr>
		<tr>
			<td>Tissue Culture Incubator</td>
			<td>Thermo Scientific</td>
			<td>50144906</td>
			<td></td>
		</tr>
		<tr>
			<td>Tissue Strainer, 250 &#181;m</td>
			<td>Pierce</td>
			<td>87791</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypan Blue Stain</td>
			<td>Gibco</td>
			<td>15250061</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin</td>
			<td>Gibco</td>
			<td>15400054</td>
			<td>0.1% Working Solution</td>
		</tr>
		<tr>
			<td>Tweezers, 110 mm</td>
			<td>Roboz Surgical</td>
			<td>RS-5035</td>
			<td></td>
		</tr>
		<tr>
			<td>Type 1 Collagenase</td>
			<td>Gibco</td>
			<td>17100017</td>
			<td></td>
		</tr>
		<tr>
			<td>Water Bath</td>
			<td>Fisher Scientific</td>
			<td>15-462-10</td>
			<td></td>
		</tr>
		<tr>
			<td>Whatman Grade 1 Filter Paper</td>
			<td>Whatman</td>
			<td>1001-110</td>
			<td></td>
		</tr>
	</tbody>
</table>

isolation of preadipocytes from broiler chick embryos

Primary preadipocytes are a valuable experimental system for understanding the molecular pathways that control adipocyte differentiation and metabolism. Chicken embryos provide the opportunity to isolate preadipocytes from the earliest stage of adipose development. This primary cell can be used to identify factors influencing preadipocyte proliferation and adipogenic differentiation, making them a valuable model for studies related to childhood obesity and control of excess fat deposition in poultry. The rapid growth of postnatal adipose tissue effectively wastes feed by allocating it away from muscle growth in broiler chickens. Therefore, methods to understand the earliest stages of adipose tissue development may provide clues to regulate this tendency and identify ways to limit adipose expansion early in life. The present study was designed to develop an efficient method for isolation, primary culture, and adipogenic differentiation of preadipocytes isolated from developing adipose tissue of commercial broiler (meat-type) chick embryos. The procedure has been optimized to yield cells with high viability (~98%) and increased capacity to differentiate into mature adipocytes. This simple method of embryonic preadipocyte isolation, culture, and differentiation supports functional analyses of fat growth and development in early life.

Primary preadipocytes are morphologically similar to fibroblasts, with irregular, star-like shapes and a central nucleus (Figure 2A-C). The cells readily adhere to tissue culture plastic and begin to proliferate soon after attachment. They rapidly differentiate and accumulate lipid droplets (Figure 3D) when provided with fatty acids in the media. The viability (98%, based on dye exclusion) reported in the isolations represented here is typical. While the cells are fairly robust, aggressive handling during isolation leads to cell damage (Figure 3E), yielding cells that attach poorly and fail to proliferate. Despite the procedures incorporated to prevent microbial contamination, transfer of non-sterile material can occur (Figure 3F). Because of their rapid growth rate, chick embryo preadipocytes consume glucose in the media at high rates. Media should be changed every 48 h to maintain their supply of energy.
The representative results presented here illustrate the adipogenic potential of chick embryo preadipocytes. These cells quickly accumulate to develop lipid droplets under adipogenic conditions, and accumulation progresses over time (Figure&#160;4 and Figure 5). Two methods have been presented which can be used to better visualize and quantify the degree of lipid accumulation in these cells, which is a direct reflection of adipogenesis. Staining lipids with Oil Red O is a low-cost method to visualize and quantify the accumulation of lipid droplets (Figure 4). A light microscope is used to collect images, and stained cells can be held on the benchtop until images are collected. Lipid accumulation in each dish of cells can be quantified as described by extracting the stain and reading the absorbance at 495 nm using a spectrophotometer. Using the combination of the selected lipid and DNA stains, it was possible to quantify the lipid accumulation relative to cell number, which compensates for non-adipogenic cells that may persist in culture (Figure 5). If measures are taken over several time points (Figure 5B-C), this combination makes it possible to assess both adipogenesis and proliferation, for example in response to added hormones or peptides.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/63861/63861fig01.jpg" /> 
Figure 1: Adipose tissue collection. (A) On breaking the eggshell, the white shell membrane was revealed. (B) Piercing the amnion using sterile tweezers. (C) A total of ~80 mg of femoral subcutaneous fat can be obtained from E16. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63861/63861fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/63861/63861fig02.jpg" /> 
Figure 2: Tissue fragments for enzymatic digestion and cell pellet after digestion. (A)&#160;Minced adipose tissue in enzymatic solution (~1 mm3). (B) Arrows indicate cell pellets after RBC lysis. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63861/63861fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/63861/63861fig03.jpg" /> 
Figure 3: Cell morphology comparisons of isolated primary preadipocytes. (A) Preadipocytes at 24 h after isolation. (B) Preadipocytes at 48 h after isolation. (C) Preadipocytes with 80% confluency at 72 h after isolation. (D) Preadipocytes after 48 h adipogenic induction at passage 4, lipid droplets are visible. Inset indicates the magnified image of lipid droplets. (E) Representative image of damaged cells. (F) Arrow indicates black swimming dots in contaminated culture. Scale bars = 100 &#181;m. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63861/63861fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/63861/63861fig04.jpg" /> 
Figure 4: Evaluation of lipid accumulation by Oil Red O staining. (A) Representative images of Oil Red O staining of E16 preadipocytes after 24 h, 48 h, and 72 h adipogenic differentiation ex vivo. Scale bars = 100 &#181;m. (B) Quantification of lipid droplets measured by elution of Oil Red O staining. Values are expressed as mean &#177; SD. a,b,c P &#60; 0.05 by one-way ANOVA with posthoc Tukey&#39;s HSD test. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63861/63861fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/63861/63861fig05.jpg" /> 
Figure 5: Assessment of adipocyte differentiation by lipid stain/DNA stain. (A) Representative images of the lipid stain (red) and the DNA (blue) staining of E16 preadipocytes after 24 h, 48 h, and 72 h adipogenic differentiation ex vivo. Scale bars = 150 &#181;m. (B) Lipid staining (Excitation: 485 nm/Emission: 572 nm) was performed to assess lipid accumulation in differentiated preadipocytes. (C) DNA staining (Excitation: 359 nm/Emission: 450 nm) was performed to assess variations in the number of cells. (D) The ratio of lipid and DNA stain. Lipid accumulation is normalized to the DNA content. Values are expressed as mean &#177; SD. a,b,c P &#60; 0.05 by one-way ANOVA with posthoc Tukey&#39;s HSD test. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63861/63861fig05large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Age (n=)</td>
			<td>x106 cells/100 mg tissue</td>
			<td>Viability (%)</td>
		</tr>
		<tr>
			<td>E12 (4)</td>
			<td>0.97 &#177; 0.115 a,b</td>
			<td>98.5 &#177; 0.58 a</td>
		</tr>
		<tr>
			<td>E14 (4)</td>
			<td>1.22 &#177; 0.232 a,b</td>
			<td>98.3 &#177; 0.96 a,b</td>
		</tr>
		<tr>
			<td>E16 (21)</td>
			<td>1.61 &#177; 1.717 a</td>
			<td>97.6 &#177; 1.58 a</td>
		</tr>
		<tr>
			<td>E17 (4)</td>
			<td>0.81 &#177; 0.282 a,b</td>
			<td>96.8 &#177; 2.63 a,b</td>
		</tr>
		<tr>
			<td>E18 (7)</td>
			<td>0.72 &#177; 0.611 a,b</td>
			<td>95.9 &#177; 1.81 a,b</td>
		</tr>
		<tr>
			<td>E20 (4)</td>
			<td>0.94 &#177; 0.171 a,b</td>
			<td>97.8 &#177; 0.8 a,b</td>
		</tr>
		<tr>
			<td>D4 (9)</td>
			<td>0.24 &#177; 0.164 a,b</td>
			<td>93.6 &#177; 4.28 b</td>
		</tr>
		<tr>
			<td>D5 (4)</td>
			<td>0.25 &#177; 0.073 a,b</td>
			<td>98.5 &#177; 0.71 a,b</td>
		</tr>
		<tr>
			<td>D7 (10)</td>
			<td>0.17 &#177; 0.162 b</td>
			<td>96.8 &#177; 3.49 a,b</td>
		</tr>
		<tr>
			<td>D14 (4)</td>
			<td>0.25 &#177; 0.051 a,b</td>
			<td>99.0 &#177; 0.00 a,b</td>
		</tr>
	</tbody>
</table>
Table 1: Average cell number and viability of isolated cells from embryo and post-hatch chicks. 
Values are expressed as mean &#177; SD. a,b P &#60; 0.05 by one-way ANOVA with posthoc Tukey&#39;s HSD test.

Watch this Scientific Journal Video about Isolation of Preadipocytes from Broiler Chick Embryos at JoVE.com

Isolation of Preadipocytes from Broiler Chick Embryos

The present protocol describes a simple method for isolating preadipocytes from adipose tissue in broiler embryos. This method enables isolation with high yield, primary culture, and adipogenic differentiation of preadipocytes. Oil Red O staining and lipid/DNA stain measured the adipogenic ability of isolated cells induced with differentiation media.

Primary preadipocytes are a valuable experimental system for understanding the molecular pathways that control adipocyte differentiation and metabolism. ...

isolation-of-preadipocytes-from-broiler-chick-embryos

Nanyang Technological University

Research

JoVE Journal

Developmental Biology

2.2K Views.  University of Tennessee. The present protocol describes a simple method for isolating preadipocytes from adipose tissue in broiler embryos. This method enables isolation with high yield, primary culture, and adipogenic differentiation of preadipocytes. Oil Red O staining and lipid/DNA stain measured the adipogenic ability of isolated cells induced with differentiation media.

Video: Isolation of Preadipocytes from Broiler Chick Embryos

Optimized Ex-ovo Culturing of Chick Embryos to Advanced Stages of Development

Research in anatomy, embryology, and developmental biology has largely relied on the use of model organisms. In order to study development in live embryos model organisms, such as the chicken, are often used. The chicken is an excellent model organism due to its low cost and minimal maintenance, however they present observational challenges because they are enclosed in an opaque eggshell. In order to properly view the embryo as it develops, the shell must be windowed or removed. Both windowing and ex ovo techniques have been developed to assist researchers in the study of embryonic development. However, each of the methods has limitations and challenges. Here, we present a simple, optimized ex ovo culture technique for chicken embryos that enables the observation of embryonic development from stage HH 19 into late stages of development (HH 40), when many organs have developed. This technique is easy to adopt in both undergraduate classes and more advanced research laboratories where embryo manipulations are conducted.

Optimized Ex-ovo Culturing of Chick Embryos to Advanced Stages of Development

Viewing and accessing the chicken embryo during development can be challenging. We have developed an ex ovo method that is simple, cost effective, and can easily be used in a classroom or research setting. This method provides access to the embryo into late stages of embryonic development (HH 40).

Research in anatomy, embryology, and developmental biology has largely relied on the use of model organisms. In order to study development in live embryos ...

Forward Genetic Approach to Uncover Stress Resistance Genes in Mice &#8212; A High-throughput Screen in ES Cells

Phenotype-driven genetic screens in mice is a powerful technique to uncover gene functions, but are often hampered by extremely high costs, which severely limits its potential. We describe here the use of mouse embryonic stem (ES) cells as surrogate cells to screen for a phenotype of interest and subsequently introduce these cells into a host embryo to develop into a living mouse carrying the phenotype. This method provides (1) a cost effective, high-throughput platform for genetic screen in mammalian cells; (2) a rapid way to identify the mutated genes and verify causality; and (3) a short-cut to develop mouse mutants directly from these selected ES cells for whole animal studies. We demonstrated the use of paraquat (PQ) to select resistant mutants and identify mutations that confer oxidative stress resistance. Other stressors or cytotoxic compounds may also be used to screen for resistant mutants to uncover novel genetic determinants of a variety of cellular stress resistance.

Stress resistance is one of the hallmarks for longevity and is known to be genetically governed. Here, we developed an unbiased high-throughput method to screen for mutations that confer stress resistance in ES cells with which to develop mouse models for longevity studies.

Phenotype-driven genetic screens in mice is a powerful technique to uncover gene functions, but are often hampered by extremely high costs, which severely ...

Whole Retinal Explants from Chicken Embryos for Electroporation and Chemical Reagent Treatments

The retina is a good model for the developing central nervous system. The large size of the eye and most importantly the accessibility for experimental manipulations in ovo/in vivo makes the chicken embryonic retina a versatile and very efficient experimental model. Although the chicken retina is easy to target in ovo by intraocular injections or electroporation, the effective and exact concentration of the reagents within the retina may be difficult to fully control. This may be due to variations of the exact injection site, leakage from the eye or uneven diffusion of the substances. Furthermore, the frequency of malformations and mortality after invasive manipulations such as electroporation is rather high.
This protocol describes an ex ovo technique for culturing whole retinal explants from chicken embryos and provides a method for controlled exposure of the retina to reagents. The protocol describes how to dissect, experimentally manipulate, and culture whole retinal explants from chicken embryos. The explants can be cultured for approximately 24 hr and be subjected to different manipulations such as electroporation. The major advantages are that the experiment is not dependent on the survival of the embryo and that the concentration of the introduced reagent can be varied and controlled in order to determine and optimize the effective concentration. Furthermore, the technique is rapid, cheap and together with its high experimental success rate, it ensures reproducible results. It should be emphasized that it serves as an excellent complement to experiments performed in ovo.

This protocol describes a method to dissect, experimentally manipulate and culture whole retinal explants from chicken embryos. The explant cultures are useful when high success rate, efficacy and reproducibility are needed to test the effects of plasmids for electroporation and/or reagent substances, i.e., enzymatic inhibitors.

The retina is a good model for the developing central nervous system. The large size of the eye and most importantly the accessibility for experimental ...

Primary Endodermal Epithelial Cell Culture from the Yolk Sac Membrane of Japanese Quail Embryos

We established an endodermal epithelial cell culture model (EEC) for studying the function of certain enzymes and proteins in mediating nutrient utilization by avian embryos during development. Fertilized Japanese quail eggs were incubated at 37 &#176;C for 5 days and then yolk sac membranes (YSM) were collected to establish the EEC culture system. We isolated the embryonic endoderm layer from YSM, and sliced the membrane into 2 - 3 mm pieces and partially digested with collagenase before seeding in 24-well culture plates. The EECs proliferate out of the tissue and are ready for cell culture studies. We found that the EECs had typical characteristics of YSM in vivo, for example, accumulation of lipid droplets, expression of sterol O-acyltransferase and lipoprotein lipase. The partial digestion treatment significantly increased the successful rate of EEC culture. Utilizing the EECs, we demonstrated that the expression of SOAT1 was regulated by the cAMP dependent protein kinase A related pathway. This primary Japanese quail EEC culture system is a useful tool to study embryonic lipid transportation and to clarify the role of genes involved in mediating nutrient utilization in YSM during avian embryonic development.

To study the mechanism of lipid utilization in yolk sac membranes during the late stages of avian embryonic development, we established a primary Japanese quail embryonic endodermal epithelial cell culture system.

We established an endodermal epithelial cell culture model (EEC) for studying the function of certain enzymes and proteins in mediating nutrient ...

Isolation and Characterization of Single Cells from Zebrafish Embryos

The zebrafish (Danio rerio) is a powerful model organism to study vertebrate development. Though many aspects of zebrafish embryonic development have been described at the morphological level, little is known about the molecular basis of cellular changes that occur as the organism develops. With recent advancements in microfluidics and multiplexing technologies, it is now possible to characterize gene expression in single cells. This allows for investigation of heterogeneity between individual cells of specific cell populations to identify and classify cell subtypes, characterize intermediate states that occur during cell differentiation, and explore differential cellular responses to stimuli. This study describes a protocol to isolate viable, single cells from zebrafish embryos for high throughput multiplexing assays. This method may be rapidly applied to any zebrafish embryonic cell type with fluorescent markers. An extension of this method may also be used in combination with high throughput sequencing technologies to fully characterize the transcriptome of single cells. As proof of principle, the relative abundance of cardiac differentiation markers was assessed in isolated, single cells derived from nkx2.5 positive cardiac progenitors. By evaluation of gene expression at the single cell level and at a single time point, the data support a model in which cardiac progenitors coexist with differentiating progeny. The method and work flow described here is broadly applicable to the zebrafish research community, requiring only a labeled transgenic fish line and access to microfluidics technologies.

This protocol describes a method for isolating single cells from zebrafish embryos, enriching for cells of interest, capturing zebrafish cells in microfluidic based single cell multiplex systems, and assessing gene expression from single cells.

The zebrafish (Danio rerio) is a powerful model organism to study vertebrate development. Though many aspects of zebrafish embryonic development have been ...

Affinity Labeling Detection of Endogenous Receptors from Zebrafish Embryos

By combining the powers of Affinity Labeling and Immunoprecipitation (AFLIP), a technique for the detection of low abundance receptors in zebrafish embryos has been implemented. This technique takes advantage of the selectivity and sensitivity conferred by affinity labeling of a given receptor by its ligand with the specificity of the immunoprecipitation. We have used AFLIP to detect the type III TGF-&#946; receptor (TGFBR3), also know as betaglycan, during early zebrafish development. AFLIP was instrumental in validating the efficacy of a TGFBR3 morphant zebrafish phenotype. In the first step, embryo protein extracts are prepared and used to generate 125I-TGF-&#946;2-TGFBR3 complexes that are purified by immunoprecipitation. Later, these complexes are covalently cross-linked and revealed using SDS-PAGE separation and autoradiography detection. This technique requires the availability of a labeled ligand for, and a specific antibody against, the receptor to be detected, and shall be easily adapted to identify any growth factor or cytokine receptor that meets these requirements.

A novel technique for the detection of low abundance endogenous receptors present in zebrafish embryos is described. We have named it AFLIP because it consists of affinity labeling of the receptor by its ligand linked to immunoprecipitation.

By combining the powers of Affinity Labeling and Immunoprecipitation (AFLIP), a technique for the detection of low abundance receptors in zebrafish ...

A Submerged Filter Paper Sandwich for Long-term Ex Ovo Time-lapse Imaging of Early Chick Embryos

Due to its availability, low cost, flat geometry, and transparency, the ex ovo chick embryo has become a major vertebrate animal model for the study of morphogenetic events, such as gastrulation2, neurulation3-5, somitogenesis6, heart bending7,8, and brain formation9-13, during early embryogenesis. Key to understanding morphogenetic processes is to follow them dynamically by time-lapse imaging. The acquisition of time-lapse movies of chick embryogenesis ex ovo has been limited either to short time windows or to the need for an incubator to control temperature and humidity around the embryo14. Here, we present a new technique to culture chick embryos ex ovo for high-resolution time-lapse imaging using transmitted light microscopy. The submerged filter paper sandwich is a variant of the well-established filter paper carrier technique (EC-culture)1 and allows for the culturing of chick embryos without the need for a climate chamber. The embryo is sandwiched between two identical filter paper carriers and is kept fully submerged in a simple, temperature-controlled medium covered by a layer of light mineral oil. Starting from the primitive streak stage (Hamburger-Hamilton stage 5, HH5)15 up to at least the 28-somite stage (HH16)15, embryos can be cultured with either their ventral or dorsal side up. This allows the acquisition of time-lapse movies covering about 30 hr of embryonic development. Representative time-lapse frames and movies are shown. Embryos are compared morphologically to an embryo cultured in the standard EC-culture.
The submerged filter paper sandwich provides a stable environment to study early dorsal and ventral morphogenetic processes. It also allows for live fluorescence imaging and micromanipulations, such as microsurgery, bead implantation, microinjection, gene silencing, and electroporation, and has a strong potential to be combined with immersion objectives for laser-based imaging (including light-sheet microscopy).

A Submerged Filter Paper Sandwich for Long-term Ex Ovo Time-lapse Imaging of Early Chick Embryos

Here, we present a new technique to culture chick embryos ex ovo for time-lapse imaging using transmitted light and fluorescence microscopy. The submerged filter paper sandwich is a variant of the well-established filter paper carrier technique1 that allows for the culturing of chick embryos fully-submerged in a liquid culture medium.

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Perfusion-based islet-isolation protocols from large mammalian pancreata are well established. Such protocols are readily conducted in many laboratories due to the large size of the pancreatic duct that allows for ready collagenase injection and subsequent tissue perfusion. In contrast, islet isolation from small pancreata, like that of neonatal mice, is challenging because perfusion is not readily achievable in the small pancreata. Here we describe a detailed simple procedure that recovers substantial numbers of islets from newly born mice with visual assistance. Freshly dissected whole pancreata were digested with 0.5 mg/mL collagenase IV dissolved in Hanks&#39; Balanced Salt Solution (HBSS) at 37 &#176;C, in microcentrifuge tubes. Tubes were tapped regularly to aid tissue dispersal. When most of the tissue was dispersed to small clusters around 1 mm, lysates were washed three to four times with culture media with 10% fetal bovine serum (FBS). Islet clusters, devoid of recognizable acinar tissues, can then be recovered under dissecting stereoscope. This method recovers 20 - 80 small- to large-sized islets per pancreas of newly born mouse. These islets are suitable for most conceivable downstream assays, including insulin secretion, gene expression, and culture. An example of insulin secretion assay is presented to validate the isolation process. The genetic background and degree of digestion are the largest factors determining the yield. Freshly made collagenase solution with high activity is preferred, as it aids in endocrine-exocrine isolation. The presence of cations [calcium (Ca2+) and magnesium (Mg2+)] in all solutions and fetal bovine serum in the wash/picking media are necessary for good yield of islets with proper integrity. A dissecting scope with good contrast and magnification will also help.

We describe a protocol herein for isolating intact islets from neonatal mice. Pancreata were partially digested with collagenase, followed by washing and hand picking. 20 - 80 islet clusters can be obtained per pancreas from newly born mice, which are suitable for several islet studies.

Perfusion-based islet-isolation protocols from large mammalian pancreata are well established. Such protocols are readily conducted in many laboratories ...

Derivation of Stem Cell Lines from Mouse Preimplantation Embryos

Mouse embryonic stem cell (mESC) derivation is the process by which pluripotent cell lines are established from preimplantation embryos. These lines retain the ability to either self-renew or differentiate under specific conditions. Due to these properties, mESC are a useful tool in regenerative medicine, disease modeling, and tissue engineering studies. This article describes a simple protocol to obtain mESC lines with high derivation efficiencies (60-80%) by culturing blastocysts from permissive mouse strains on feeder cells in defined medium supplemented with leukemia inhibitory factor. The protocol can also be applied to efficiently derive mESC lines from non-permissive mouse strains, by the simple addition of a cocktail of two small-molecule inhibitors to the derivation medium (2i medium). Detailed procedures on the preparation and culture of feeder cells, collection and culture of mouse embryos, and derivation and culture of mESC lines are provided. This protocol does not require specialized equipment and can be carried out in any laboratory with basic mammalian cell culture expertise.

This article describes a protocol to efficiently derive and culture pluripotent stem cell lines from mouse embryos at the blastocyst stage.

Mouse embryonic stem cell (mESC) derivation is the process by which pluripotent cell lines are established from preimplantation embryos. These lines ...

Isolation of Specific Neuron Populations from Roundworm Caenorhabditis elegans

During the aging process, many cells accumulate high levels of damage leading to cellular dysfunction, which underlies many geriatric and pathological conditions. Post-mitotic neurons represent a major cell type affected by aging. Although multiple mammalian models of neuronal aging exist, they are challenging and expensive to establish. The roundworm Caenorhabditis elegans is a powerful model to study neuronal aging, as these animals have short lifespan, an available robust genetic toolbox, and well-cataloged nervous system. The method presented herein allows for seamless isolation of specific cells based on the expression of a transgenic green fluorescent protein (GFP). Transgenic animal lines expressing GFP under distinct, cell type-specific promoters are digested to remove the outer cuticle and gently mechanically disrupted to produce slurry containing various cell types. The cells of interest are then separated from non-target cells through fluorescence-activated cell sorting, or by anti-GFP-coupled magnetic beads. The isolated cells can then be cultured for a limited time or immediately used for cell-specific ex vivo analyses such as transcriptional analysis by real time quantitative PCR. Thus, this protocol allows for rapid and robust analysis of cell-specific responses within different neuronal populations in C. elegans.

Isolation of Specific Neuron Populations from Roundworm Caenorhabditis elegans

Here, we present a protocol for simple isolation of specific groups of live neuronal cells expressing green fluorescent protein from transgenic Caenorhabditis elegans lines. This method enables a variety of ex vivo studies focused on specific neurons and has the capacity to isolate cells for further short-term culturing.

During the aging process, many cells accumulate high levels of damage leading to cellular dysfunction, which underlies many geriatric and pathological ...

Isolation of Preadipocytes from Broiler Chick Embryos

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Optimized Ex-ovo Culturing of Chick Embryos to Advanced Stages of Development

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Whole Retinal Explants from Chicken Embryos for Electroporation and Chemical Reagent Treatments

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Effective Isolation of Functional Islets from Neonatal Mouse Pancreas

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