This work was supported in part by NIH awards F30HL154324 to O.T. and K08HL121191 and R03HL154301 to S.R.K. The authors would like to acknowledge that the schematic in Figure 1 in this manuscript was created with biorender.com.

<ol>
	<li>Ho, H. Y. H., 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=Wnt5a-Ror-Dishevelled+signaling+constitutes+a+core+developmental+pathway+that+controls+tissue+morphogenesis.">Wnt5a-Ror-Dishevelled signaling constitutes a core developmental pathway that controls tissue morphogenesis.</a> Proceedings of the National Academy of Sciences of the United States of America. 109 (11), 4044-4051 (2012).</li><li>&#268;apek, D., 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=Light-activated+Frizzled7+reveals+a+permissive+role+of+noncanonical+wnt+signaling+in+mesendoderm+cell+migration.">Light-activated Frizzled7 reveals a permissive role of noncanonical wnt signaling in mesendoderm cell migration.</a> Elife. (8), 42093 (2019).</li><li>Li, D., 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=Planar+cell+polarity+signaling+regulates+polarized+second+heart+field+morphogenesis+to+promote+both+arterial+and+venous+pole+septation.">Planar cell polarity signaling regulates polarized second heart field morphogenesis to promote both arterial and venous pole septation.</a> Development. 146 (20), 181719 (2019).</li><li>Lutze, G., 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=Noncanonical+WNT-signaling+controls+differentiation+of+lymphatics+and+extension+lymphangiogenesis+via+RAC+and+JNK+signaling.">Noncanonical WNT-signaling controls differentiation of lymphatics and extension lymphangiogenesis via RAC and JNK signaling.</a> Scientific Reports. 9 (1), 4739 (2019).</li><li>Buttler, K., 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=Maldevelopment+of+dermal+lymphatics+in+Wnt5a-knockout-mice.">Maldevelopment of dermal lymphatics in Wnt5a-knockout-mice.</a> Developmental Biology. 381 (2), 365-376 (2013).</li><li>Betterman, K. L., 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=Atypical+cadherin+FAT4+orchestrates+lymphatic+endothelial+cell+polarity+in+response+to+flow.">Atypical cadherin FAT4 orchestrates lymphatic endothelial cell polarity in response to flow.</a> Journal of Clinical Investigation. 130 (6), 3315-3328 (2020).</li><li>Descamps, 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=Frizzled+4+regulates+arterial+network+organization+through+noncanonical+Wnt/planar+cell+polarity+signaling.">Frizzled 4 regulates arterial network organization through noncanonical Wnt/planar cell polarity signaling.</a> Circulation Research. 110 (1), 47-58 (2012).</li><li>Weeraratna, A. T., 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=Wnt5a+signaling+directly+affects+cell+motility+and+invasion+of+metastatic+melanoma.">Wnt5a signaling directly affects cell motility and invasion of metastatic melanoma.</a> Cancer Cell. 1 (3), 279-288 (2002).</li><li>Henry, C., 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=Expression+of+the+novel+Wnt+receptor+ROR2+is+increased+in+breast+cancer+and+may+regulate+both+&#946;-catenin+dependent+and+independent+Wnt+signalling.">Expression of the novel Wnt receptor ROR2 is increased in breast cancer and may regulate both &#946;-catenin dependent and independent Wnt signalling.</a> Journal of Cancer Research and Clinical Oncology. 141 (2), 243-254 (2014).</li><li>Anastas, J. N., 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=A+protein+complex+of+SCRIB,+NOS1AP+and+VANGL1+regulates+cell+polarity+and+migration,+and+is+associated+with+breast+cancer+progression.">A protein complex of SCRIB, NOS1AP and VANGL1 regulates cell polarity and migration, and is associated with breast cancer progression.</a> Oncogene. 31 (32), 3696-3708 (2012).</li><li>Niehrs, 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+complex+world+of+WNT+receptor+signalling.">The complex world of WNT receptor signalling.</a> Nature Reviews Molecular Cell Biology. 13 (12), 767-779 (2012).</li><li>Dong, 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=Functional+redundancy+of+frizzled+3+and+frizzled+6+in+planar+cell+polarity+control+of+mouse+hair+follicles.">Functional redundancy of frizzled 3 and frizzled 6 in planar cell polarity control of mouse hair follicles.</a> Development. 145 (19), (2018).</li><li>Bernascone, I., 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=Sfrp3+modulates+stromal-epithelial+crosstalk+during+mammary+gland+development+by+regulating+Wnt+levels.">Sfrp3 modulates stromal-epithelial crosstalk during mammary gland development by regulating Wnt levels.</a> Nature Communications. 10 (1), 2481 (2019).</li><li>Hendrickx, G., 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=WNT16+requires+G&#945;+subunits+as+intracellular+partners+for+both+its+canonical+and+noncanonical+WNT+signalling+activity+in+osteoblasts.">WNT16 requires G&#945; subunits as intracellular partners for both its canonical and noncanonical WNT signalling activity in osteoblasts.</a> Calcified Tissue International. 106 (3), 294-302 (2020).</li><li>Avgustinova, A., 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=Tumour+cell-derived+Wnt7a+recruits+and+activates+fibroblasts+to+promote+tumour+aggressiveness.">Tumour cell-derived Wnt7a recruits and activates fibroblasts to promote tumour aggressiveness.</a> Nature Communications. (7), 10305 (2016).</li><li>Tseng, J. C., 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=CAPE+suppresses+migration+and+invasion+of+prostate+cancer+cells+via+activation+of+noncanonical+Wnt+signaling.">CAPE suppresses migration and invasion of prostate cancer cells via activation of noncanonical Wnt signaling.</a> Oncotarget. 7 (25), 38010-38024 (2016).</li><li>Wang, Q., 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=A+novel+role+for+Wnt/Ca2++signaling+in+actin+cytoskeleton+remodeling+and+cell+motility+in+prostate+cancer.">A novel role for Wnt/Ca2+ signaling in actin cytoskeleton remodeling and cell motility in prostate cancer.</a> PLoS One. 5 (5), 10456 (2010).</li><li>Gibbs, B. C., 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=Prickle1+mutation+causes+planar+cell+polarity+and+directional+cell+migration+defects+associated+with+cardiac+outflow+tract+anomalies+and+other+structural+birth+defects.">Prickle1 mutation causes planar cell polarity and directional cell migration defects associated with cardiac outflow tract anomalies and other structural birth defects.</a> Biology Open. 5 (3), 323-335 (2016).</li><li>Cui, C., 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=a+PCP+protein+required+for+ciliogenesis,+regulates+directional+cell+migration+and+cell+polarity+by+direct+modulation+of+the+actin+cytoskeleton.">a PCP protein required for ciliogenesis, regulates directional cell migration and cell polarity by direct modulation of the actin cytoskeleton.</a> PLoS Biology. 11 (11), 1001720 (2013).</li><li>Gombos, R., 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=The+formin+DAAM+functions+as+molecular+effector+of+the+planar+cell+polarity+pathway+during+axonal+development+in+Drosophila.">The formin DAAM functions as molecular effector of the planar cell polarity pathway during axonal development in Drosophila.</a> The Journal of Neuroscience. 35 (28), 10154-10167 (2015).</li><li>Toubat, O., 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=Neural+Crest+Cell-derived+Wnt5a+Regulates+Planar+Cell+Polarity+in+Cranial+Second+Heart+Field+Progenitor+Cells.">Neural Crest Cell-derived Wnt5a Regulates Planar Cell Polarity in Cranial Second Heart Field Progenitor Cells.</a> Circulation. 142, 12540 (2020).</li><li>Li, D., 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=Spatial+regulation+of+cell+cohesion+by+Wnt5a+during+second+heart+field+progenitor+deployment.">Spatial regulation of cell cohesion by Wnt5a during second heart field progenitor deployment.</a> Developmental Biology. 412 (1), 18-31 (2016).</li><li>Sinha, T., 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=Loss+of+Wnt5a+disrupts+second+heart+field+cell+deployment+and+may+contribute+to+OFT+malformations+in+DiGeorge+syndrome.">Loss of Wnt5a disrupts second heart field cell deployment and may contribute to OFT malformations in DiGeorge syndrome.</a> Human Molecular Genetics. 24 (6), 1704-1716 (2015).</li><li>Humphries, A. C., 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=From+instruction+to+output:+Wnt/PCP+signaling+in+development+and+cancer.">From instruction to output: Wnt/PCP signaling in development and cancer.</a> Current Opinion in Cell Biology. (51), 110-116 (2018).</li><li>Shi, 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=Decoding+Dishevelled-Mediated+Wnt+Signaling+in+Vertebrate+Early+Development.">Decoding Dishevelled-Mediated Wnt Signaling in Vertebrate Early Development.</a> Frontiers in Cell and Developmental Biology. (8), 588370 (2020).</li><li>Butler, M. T., 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=Planar+cell+polarity+in+development+and+disease.">Planar cell polarity in development and disease.</a> Nature Reviews Molecular Cell Biology. 18 (6), 375-388 (2017).</li><li>Bradshaw, L., 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=Dual+role+for+neural+crest+cells+during+outflow+tract+septation+in+the+neural+crest-deficient+mutant+Splotch2H.">Dual role for neural crest cells during outflow tract septation in the neural crest-deficient mutant Splotch2H.</a> Journal of Anatomy. 214 (2), 245-257 (2009).</li><li>Kodo, K., 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=Regulation+of+Sema3c+and+the+interaction+between+cardiac+neural+crest+and+second+heart+field+during+outflow+tract+development.">Regulation of Sema3c and the interaction between cardiac neural crest and second heart field during outflow tract development.</a> Scientific Reports. 7 (1), 6771 (2017).</li><li>Waldo, K. L., 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=Cardiac+neural+crest+is+necessary+for+normal+addition+of+the+myocardium+to+the+arterial+pole+from+the+secondary+heart+field.">Cardiac neural crest is necessary for normal addition of the myocardium to the arterial pole from the secondary heart field.</a> Developmental Biology. 281 (1), 66-77 (2005).</li><li>Schleiffarth, J. R., 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=Wnt5a+is+required+for+cardiac+outflow+tract+septation+in+mice.">Wnt5a is required for cardiac outflow tract septation in mice.</a> Pediatric Research. 61 (4), 386-391 (2007).</li><li>Nguyen, B. H., 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=Culturing+and+Manipulation+of+O9-1+Neural+Crest+Cells.">Culturing and Manipulation of O9-1 Neural Crest Cells.</a> Journal of Visualized Experiments. (140), e58346 (2018).</li><li>Suarez-Arnedo, A., 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=An+image+J+plugin+for+the+high+throughput+image+analysis+of+in+vitro+scratch+wound+healing+assays.">An image J plugin for the high throughput image analysis of in vitro scratch wound healing assays.</a> PLoS One. 15 (7), 0232565 (2020).</li><li>Martinotti, 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=Scratch+wound+healing+assay.">Scratch wound healing assay.</a> Methods in Molecular Biology. (2109), 225-229 (2020).</li></ol>

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

The noncanonical Wnt/planar cell polarity (PCP) signaling pathway is a critically important cellular signaling pathway that has been implicated in multiple developmental24,25 and disease processes24,26. During embryonic development, noncanonical Wnt signaling involves an expansive network of molecular signals from signal-sending cells that ultimately induce changes in morphology, asymmetric organ...

Noncanonical Wnt signaling is an evolutionarily conserved pathway that regulates cellular filament organization and directional migration. This pathway has been implicated in multiple biological processes, including embryonic tissue morphogenesis1,2,3, lymphatic and vascular angiogenesis4,5,6,7, and cancer growth and metastasis8,9,10. At the cellular level, noncanonical Wnt signaling is carried out through coordinated paracrine interactions between signal-sending and signal-receiving cells. These interactions frequently occur between cells of different lineages or types and involve a diverse molecular network that includes up to 19 ligands and multiple receptors, co-receptors, and downstream signal transduction effectors11. Further complicating this signaling process, previous studies have shown that ligand-receptor combinations can vary in a context- and tissue-dependent manner12,13, and that the same source ligands that drive noncanonical Wnt signaling in signal-receiving cells can be produced by multiple signal-sending cell types14,15. Given the cellular and molecular complexity associated with noncanonical Wnt signaling, the ability to study individual and clinically relevant mechanisms in vivo has been limited.
Attempts have been made to study noncanonical Wnt signaling using cell culture&#160;techniques in vitro. For example, wound-healing assays performed in cellular monolayers have been used to functionally assess cellular directional migration4,16,17,18,19. Immunostaining techniques have been used to perform spatial analyses of surface protein expression to evaluate noncanonical Wnt-induced changes in cellular morphology7,10, architecture, and asymmetric polarization18,19,20. Although these approaches have provided important tools for characterizing Wnt-related phenotypes in signal-receiving cells, the lack of signal-sending components in these protocols limits their ability to accurately model paracrine signaling mechanisms observed in vivo. As a result, there remains a critical need to develop in vitro systems that allow robust and reproducible evaluation of paracrine signaling interactions between signal-sending and receiving cells of the noncanonical Wnt pathway, particularly those of different cell types.
To this end, the primary objective of this study was to establish a protocol to model paracrine noncanonical Wnt signaling interactions in vitro. We developed a non-contact coculture system that recapitulates signal-sending and signal-receiving components of these interactions and allows the use of standard molecular, genetic, or pharmacologic approaches to independently study specific ligand-receptor mechanisms in the noncanonical Wnt pathway. Mechanisms of NCC-mediated Wnt signaling were examined in myoblasts using established murine cell lines. As proof of principle, this model was used to corroborate findings of prior in vivo studies in mice that implicate the Wnt5a-ROR2 axis as a relevant noncanonical Wnt signaling pathway between NCCs21 and SHF cardiomyoblast progenitors3,22,23.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>2-Mercaptoethanol</td>
			<td>Sigma Aldrich</td>
			<td>M-7522</td>
			<td></td>
		</tr>
		<tr>
			<td>Antifade mounting medium with DAPI</td>
			<td>Vector Laboratories</td>
			<td>H-1200-10</td>
			<td>Stored at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Bovine serum albumin</td>
			<td>Santa Cruz Biotechnology</td>
			<td>sc-2323</td>
			<td>Stored at 4 &#176;C</td>
		</tr>
		<tr>
			<td>C2C12 murine myoblast cell line</td>
			<td>ATCC</td>
			<td>CRL-1772</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture flasks, 75 cm2</td>
			<td>ThermoFisher Scientific</td>
			<td>156499</td>
			<td></td>
		</tr>
		<tr>
			<td>Chamber Slide System, 4-well</td>
			<td>ThermoFisher Scientific</td>
			<td>154526</td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#8217;s Modified Eagle&#8217;s Medium (DMEM), high glucose (4.5 g/L), L-glutamine (2 mM)</td>
			<td>Corning</td>
			<td>10-017-CV</td>
			<td>Stored at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Falcon conical centrifuge tubes, 15 mL</td>
			<td>Fisher Scientific</td>
			<td>14-959-53A</td>
			<td></td>
		</tr>
		<tr>
			<td>Falcon permeable support for 24-well plate with 0.4 &#181;M transparent PET membrane</td>
			<td>Corning</td>
			<td>353095</td>
			<td></td>
		</tr>
		<tr>
			<td>Fetal bovine serum</td>
			<td>Fisher Scientific</td>
			<td>W3381E</td>
			<td>Stored in 50 mL aliquots at -20 &#176;C</td>
		</tr>
		<tr>
			<td>Gelatin solution, 0.1%</td>
			<td>ATCC</td>
			<td>PCS-999-027</td>
			<td>Stored at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Graduated and sterile pipette tips, 10 &#181;L</td>
			<td>USA Scientific</td>
			<td>1111-3810</td>
			<td></td>
		</tr>
		<tr>
			<td>Leukemia inhibitory factor (LIF), 106 unit/mL</td>
			<td>Millipore Sigma</td>
			<td>ESG1106</td>
			<td></td>
		</tr>
		<tr>
			<td>L-glutamine 200 mM (100x)</td>
			<td>Gibco</td>
			<td>25030-081</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipofectamine RNAiMAX</td>
			<td>Thermo Fisher Scientific</td>
			<td>13778-075</td>
			<td></td>
		</tr>
		<tr>
			<td>MEM non-essential amino acids (MEM NEAA) 100x</td>
			<td>Gibco</td>
			<td>11140-050</td>
			<td></td>
		</tr>
		<tr>
			<td>Minimum essential medium (MEM)</td>
			<td>Corning</td>
			<td>10-022-CV</td>
			<td></td>
		</tr>
		<tr>
			<td>Mitomycin C</td>
			<td>Roche</td>
			<td>10107409001</td>
			<td></td>
		</tr>
		<tr>
			<td>Non-stick auto-glass coverslips, 24 x 55 mm</td>
			<td>Springside Scientific</td>
			<td>HRTCG2455</td>
			<td></td>
		</tr>
		<tr>
			<td>O9-1 neural crest cell line</td>
			<td>Millipore Sigma</td>
			<td>SCC049</td>
			<td></td>
		</tr>
		<tr>
			<td>Opti-MEM I, 1x</td>
			<td>Gibco</td>
			<td>31985-070</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraformaldehyde solution in PBS, 4%</td>
			<td>Santa Cruz Biotechnology</td>
			<td>sc-281692</td>
			<td>Stored at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Penicillin-streptomycin (10,000 U/mL penicillin and 10,000 &#956;g/mL streptomycin)</td>
			<td>Fisher Scientific</td>
			<td>W3470H</td>
			<td>Stored in 10 mL aliquots at -20 &#176;C</td>
		</tr>
		<tr>
			<td>Phalloidin-iFluor 488</td>
			<td>Abcam</td>
			<td>ab176753</td>
			<td>Stored at -20 &#176;C, Keep out of light</td>
		</tr>
		<tr>
			<td>Phosphate-buffer saline (PBS), 1x, without calcium and magnesium, pH 7.4</td>
			<td>Corning</td>
			<td>21-040-CV</td>
			<td>Stored at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Recombinant human fibroblast growth factor-basic (rhFGF-basic)</td>
			<td>R&#38;D Systems</td>
			<td>233-FB-025</td>
			<td></td>
		</tr>
		<tr>
			<td>Recombinant human/mouse Wnt5a protein</td>
			<td>R&#38;D Systems</td>
			<td>645-WN-010</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium pyruvate, 100 mM</td>
			<td>Gibco</td>
			<td>11360-070</td>
			<td></td>
		</tr>
		<tr>
			<td>Square Petri dish with grid</td>
			<td>Thomas Scientific</td>
			<td>1219C98</td>
			<td></td>
		</tr>
		<tr>
			<td>STO murine fibroblast feeder cells</td>
			<td>ATCC</td>
			<td>CRL-1503</td>
			<td></td>
		</tr>
		<tr>
			<td>Triton X-100 solution</td>
			<td>Sigma Aldrich</td>
			<td>X100-100ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin-EDTA, 0.25%</td>
			<td>Fisher Scientific</td>
			<td>W3513C</td>
			<td>Stored at 4 &#176;C</td>
		</tr>
		<tr>
			<td>Zeiss Apotome.2 fluoresence microscope</td>
			<td>Carl Zeiss AG</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Zeiss inverted Axio Vert.A1 light microscope</td>
			<td>Carl Zeiss AG</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Zen lite 2012 microscopy software</td>
			<td>Carl Zeiss AG</td>
			<td></td>
			<td>imaging software</td>
		</tr>
	</tbody>
</table>

modeling paracrine noncanonical wnt signaling in vitro

Noncanonical Wnt signaling regulates intracellular actin filament organization and polarized migration of progenitor cells during embryogenesis. This process requires complex and coordinated paracrine interactions between signal-sending and signal-receiving cells. Given that these interactions can occur between various types of cells from different lineages, in vivo evaluation of cell-specific defects can be challenging. The present study describes a highly reproducible method to evaluate paracrine noncanonical Wnt signaling in vitro. This protocol was designed with the ability to (1) conduct functional and molecular assessments of noncanonical Wnt signaling between any two cell types of interest; (2) dissect the role of signal-sending versus signal-receiving molecules in the noncanonical Wnt signaling pathway; and (3) perform phenotypic rescue experiments with standard molecular or pharmacologic approaches.
This protocol was used to evaluate neural crest cell (NCC)-mediated noncanonical Wnt signaling in myoblasts. The presence of NCCs is associated with an increased number of phalloidin-positive cytoplasmic filopodia and lamellipodia in myoblasts and improved myoblast migration in a wound-healing assay. The Wnt5a-ROR2 axis was identified as a crucial noncanonical Wnt signaling pathway between NCC and second heart field (SHF) cardiomyoblast progenitors. In conclusion, this is a highly tractable protocol to study paracrine noncanonical Wnt signaling mechanisms in vitro.

Effects of NCCs on migratory capacity of murine myoblasts 
This assay was first applied to evaluate the impact of NCCs on the migratory capacity of myoblasts. Figure 1 outlines the schematic model of the assay. To test this impact, scratch assays were performed with myoblasts that were grown in isolation (without NCC inserts) compared to those grown in the presence of inserts. As a positive control, 500 ng/mL of recombinant Wnt5a (rWnt5a) was added to chamber wells with...

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Modeling Paracrine Noncanonical Wnt Signaling In Vitro

The present study outlines a highly reproducible and tractable method to study paracrine noncanonical Wnt signaling events in vitro. This protocol was applied to evaluate the impact of paracrine Wnt5a signaling in murine neural crest cells and myoblasts.

Modeling Paracrine Noncanonical Wnt Signaling In Vitro

Noncanonical Wnt signaling regulates intracellular actin filament organization and polarized migration of progenitor cells during embryogenesis. This ...

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Developmental Biology

1.5K Views.  Keck School of Medicine of USC. The present study outlines a highly reproducible and tractable method to study paracrine noncanonical Wnt signaling events in vitro. This protocol was applied to evaluate the impact of paracrine Wnt5a signaling in murine neural crest cells and myoblasts. 

Video: Modeling Paracrine Noncanonical Wnt Signaling In Vitro

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

Characterizing thymic settling progenitors is important to understand the pre-thymic stages of T cell development, essential to devise strategies for T cell replacement in lymphopenic patients. We studied thymic settling progenitors from murine embryonic day 13 and 18 thymi by two complementary in vitro and in vivo techniques, both based on the &#8220;hanging drop&#8221; method. This method allowed colonizing irradiated fetal thymic lobes with E13 and/or E18 thymic progenitors distinguished by CD45 allotypic markers and thus following their progeny. Colonization with mixed populations allows analyzing cell autonomous differences in biologic properties of the progenitors while colonization with either population removes possible competitive selective pressures. The colonized thymic lobes can also be grafted in immunodeficient male recipient mice allowing the analysis of the mature T cell progeny in vivo, such as population dynamics of the peripheral immune system and colonization of different tissues and organs. Fetal thymic organ cultures revealed that E13 progenitors developed rapidly into all mature CD3+ cells and gave rise to the canonical &#947;&#948; T cell subset, known as dendritic epithelial T cells. In comparison, E18 progenitors have a delayed differentiation and were unable to generate dendritic epithelial T cells. The monitoring of peripheral blood of thymus-grafted CD3-/- mice further showed that E18 thymic settling progenitors generate, with time, larger numbers of mature T cells than their E13 counterparts, a feature that could not be appreciated in the short term fetal thymic organ cultures.

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

This article describes in vivo and in vitro methodology to characterize the thymic settling progenitors by the analysis of the kinetics of generation, phenotype and numbers of their T cell progeny.

Characterizing thymic settling progenitors is important to understand the pre-thymic stages of T cell development, essential to devise strategies for T ...

Using Confocal Analysis of Xenopus laevis to Investigate Modulators of Wnt and Shh Morphogen Gradients

This protocol describes a method to visualise ligands distributed across a field of cells. The ease of expressing exogenous proteins, together with the large size of their cells in early embryos, make Xenopus laevis a useful model for visualising GFP-tagged ligands. Synthetic mRNAs are efficiently translated after injection into early stage Xenopus embryos, and injections can be targeted to a single cell. When combined with a lineage tracer such as membrane tethered RFP, the injected cell (and its descendants) that are producing the overexpressed protein can easily be followed. This protocol describes a method for the production of fluorescently tagged Wnt and Shh ligands from injected mRNA. The methods involve the micro dissection of ectodermal explants (animal caps) and the analysis of ligand diffusion in multiple samples. By using confocal imaging, information about ligand secretion and diffusion over a field of cells can be obtained. Statistical analyses of confocal images provide quantitative data on the shape of ligand gradients. These methods may be useful to researchers who want to test the effects of factors that may regulate the shape of morphogen gradients.

Using Confocal Analysis of Xenopus laevis to Investigate Modulators of Wnt and Shh Morphogen Gradients

The manuscript here provides a simple set of methods for analysing the secretion and diffusion of fluorescently tagged ligands in Xenopus. This provides a context for testing the ability of other proteins to modify ligand distribution and allowing experiments that may give insight into mechanisms regulating morphogen gradients.

This protocol describes a method to visualise ligands distributed across a field of cells. The ease of expressing exogenous proteins, together with the ...

Studying Wnt Signaling During Patterning of Conducting Airways

Wnt signaling pathways play critical roles during development of the respiratory tract. Defining precise mechanisms of differentiation and morphogenesis controlled by Wnt signaling is required to understand how tissues are patterned during normal development. This knowledge is also critical to determine the etiology of birth defects such as lung hypoplasia and tracheobronchomalacia. Analysis of earliest stages of development of respiratory tract imposes challenges, as the limited amount of tissue prevents the performance of standard protocols better suited for postnatal studies. In this paper, we discuss methodologies to study cell differentiation and proliferation in the respiratory tract. We describe techniques such as whole mount staining, processing of the tissue for confocal microscopy and immunofluorescence in paraffin sections applied to developing tracheal lung. We also discuss methodologies for the study of tracheal mesenchyme differentiation, in particular cartilage formation. Approaches and techniques discussed in the current paper circumvent the limitation of material while working with embryonic tissue, allowing for a better understanding of the patterning process of developing conducting airways.

The use of reporter mice coupled to whole mount and section staining, microscopy and in vivo assays facilitates the analysis of mechanisms underlying the normal patterning of the respiratory tract. Here we describe how these techniques contributed to the analysis of Wnt signaling during tracheal development.

Wnt signaling pathways play critical roles during development of the respiratory tract. Defining precise mechanisms of differentiation and morphogenesis ...

In Vitro Differentiation of Mature Myofibers for Live Imaging

Skeletal muscles are composed of myofibers, the biggest cells in the mammalian body and one of the few syncytia. How the complex and evolutionarily conserved structures that compose it are assembled remains under investigation. Their size and physiological features often constrain manipulation and imaging applications. The culture of immortalized cell lines is widely used, but it can only replicate the early steps of differentiation.
Here, we describe a protocol that enables easy genetic manipulation of myofibers originating from primary mouse myoblasts. After one week of differentiation, the myofibers display contractility, aligned sarcomeres and triads, as well as peripheral nuclei. The entire differentiation process can be followed by live imaging or immunofluorescence. This system combines the advantages of the existing ex vivo and in vitro protocols. The possibility of easy and efficient transfection as well as the ease of access to all differentiation stages broadens the potential applications. Myofibers can subsequently be used not only to address relevant developmental and cell biology questions, but also to reproduce muscle disease phenotypes for clinical applications.

In Vitro Differentiation of Mature Myofibers for Live Imaging

Muscle cells are among the most complex eukaryotic cells. We present a protocol for the in vitro differentiation of highly mature myofibers that allows for genetic manipulation and clear imaging during all developmental stages.

Skeletal muscles are composed of myofibers, the biggest cells in the mammalian body and one of the few syncytia. How the complex and evolutionarily ...

Stimulation of Notch Signaling in Mouse Osteoclast Precursors

Notch signaling is a key component of multiple physiological and pathological processes. The nature of Notch signaling, however, makes in vitro investigation of its varying and sometimes contradictory roles a challenge. As a component of direct cell-cell communication with both receptors and ligands bound to the plasma membrane, Notch signaling cannot be activated in vitro by simple addition of ligands to culture media, as is possible with many other signaling pathways. Instead, Notch ligands must be presented to cells in an immobilized state. 
Variations in methods of Notch signaling activation can lead to different outcomes in cultured cells. In osteoclast precursors, in particular, differences in methods of Notch stimulation and osteoclast precursor culture and differentiation have led to disagreement over whether Notch signaling is a positive or negative regulator of osteoclast differentiation. While closer comparisons of osteoclast differentiation under different Notch stimulation conditions in vitro and genetic models have largely resolved the controversy regarding Notch signaling and osteoclasts, standardized methods of continuous and temporary stimulation of Notch signaling in cultured cells could prevent such discrepancies in the future.
This protocol describes two methods for stimulating Notch signaling specifically in cultured mouse osteoclast precursors, though these methods should be applicable to any adherent cell type with minor adjustments. The first method produces continuous stimulation of Notch signaling and involves immobilizing Notch ligand to a tissue culture surface prior to the seeding of cells. The second, which uses Notch ligand bound to agarose beads allows for temporary stimulation of Notch signaling in cells that are already adhered to a culture surface. This protocol also includes methods for detecting Notch activation in osteoclast precursors as well as representative transcriptional markers of Notch signaling activation.

Notch signaling is a form of cellular communication that relies upon direct contact between cells. To properly induce Notch signaling in vitro, Notch ligands must be presented to cells in an immobilized state. This protocol describes methods for in vitro stimulation of Notch signaling in mouse osteoclast precursors.

Notch signaling is a key component of multiple physiological and pathological processes. The nature of Notch signaling, however, makes in vitro ...

Precise Cellular Ablation Approach for Modeling Acute Kidney Injury in Developing Zebrafish

Acute Kidney Injury (AKI) is a common medical condition with a high mortality rate. With the repair abilities of the kidney, it is possible to restore adequate kidney function after supportive treatment. However, a better understanding of how nephron cell death and repair occur on the cellular level is required to minimize cell death and to enhance the regenerative process. The zebrafish pronephros is a good model system to accomplish this goal because it contains anatomical segments that are similar to the mammalian nephron. Previously, the most common model used to study kidney injury in fish was the pharmacological gentamicin model. However, this model does not allow for precise spatiotemporal control of injury, and hence it is difficult to study cellular and molecular processes involved in kidney repair. To overcome this limitation, this work presents a method through which, in contrast to the gentamicin approach, a specific Green Fuorescent Protein (GFP)-expressing nephron segment can be photoablated using a violet laser light (405 nm). This novel model of AKI provides many advantages that other methods of epithelial injury lack. Its main advantages are the ability to &#34;dial&#34; the level of injury and the precise spatiotemporal control in the robust in vivo animal model. This new method has the potential to significantly advance the level of understanding of kidney injury and repair mechanisms.

This work presents a new in vivo model of segmental kidney injury using kidney GFP transgenic zebrafish. The model allows for the induction of the targeted ablation of kidney epithelial cells to show the cellular mechanisms of nephron injury and repair.

Acute Kidney Injury (AKI) is a common medical condition with a high mortality rate. With the repair abilities of the kidney, it is possible to restore ...

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

The pancreas is a complex organ composed of many different cell types that work together to regulate blood glucose homeostasis and digestion. These cell types include enzyme-secreting acinar cells, an arborized ductal system responsible for the transportation of enzymes to the gut, and hormone-producing endocrine cells. 
Endocrine beta-cells are the sole cell type in the body that produce insulin to lower blood glucose levels. Diabetes, a disease characterized by a loss or the dysfunction of beta-cells, is reaching epidemic proportions. Thus, it is essential to establish protocols to investigate beta-cell development that can be used for screening purposes to derive the drug and cell-based therapeutics. While the experimental investigation of mouse development is essential, in vivo studies are laborious and time-consuming. Cultured cells provide a more convenient platform for screening; however, they are unable to maintain the cellular diversity, architectural organization, and cellular interactions found in vivo. Thus, it is essential to develop new tools to investigate pancreatic organogenesis and physiology.
Pancreatic epithelial cells develop in the close association with mesenchyme from the onset of organogenesis as cells organize and differentiate into the complex, physiologically competent adult organ. The pancreatic mesenchyme provides important signals for the endocrine development, many of which are not well understood yet, thus difficult to recapitulate during the in vitro culture. Here, we describe a protocol to culture three-dimensional, cellular complex mouse organoids that retain mesenchyme, termed pancreatoids. The e10.5 murine pancreatic bud is dissected, dissociated, and cultured in a scaffold-free environment. These floating cells self-assemble with mesenchyme enveloping the developing pancreatoid and a robust number of endocrine beta-cells developing along with the acinar and the duct cells. This system can be used to study the cell fate determination, structural organization, and morphogenesis, cell-cell interactions during organogenesis, or for the drug, small molecule, or genetic screening.

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

Here, we present a protocol to generate insulin expressing 3D murine pancreatoids from free-floating e10.5 dissociated pancreatic progenitors and the associated mesenchyme.

The pancreas is a complex organ composed of many different cell types that work together to regulate blood glucose homeostasis and digestion. These cell ...

RNA-based Reprogramming of Human Primary Fibroblasts into Induced Pluripotent Stem Cells

Induced pluripotent stem cells (iPSCs) have proven to be a valuable tool to study human development and disease. Further advancing iPSCs as a regenerative therapeutic requires a safe, robust, and expedient reprogramming protocol. Here, we present a clinically relevant, step-by-step protocol for the extremely high-efficiency reprogramming of human dermal fibroblasts into iPSCs using a non-integrating approach. The core of the protocol consists of expressing pluripotency factors (SOX2, KLF4, cMYC, LIN28A, NANOG, OCT4-MyoD fusion) from in vitro transcribed messenger RNAs synthesized with modified nucleotides (modified mRNAs). The reprogramming modified mRNAs are transfected into primary fibroblasts every 48 h together with mature embryonic stem cell-specific microRNA-367/302 mimics for two weeks. The resulting iPSC colonies can then be isolated and directly expanded in feeder-free conditions. To maximize efficiency and consistency of our reprogramming protocol across fibroblast samples, we have optimized various parameters including the RNA transfection regimen, timing of transfections, culture conditions, and seeding densities. Importantly, our method generates high-quality iPSCs from most fibroblast sources, including difficult-to-reprogram diseased, aged, and/or senescent samples.

Here we describe a clinically relevant, high-efficiency, feeder-free method to reprogram human primary fibroblasts into induced pluripotent stem cells using modified mRNAs encoding reprogramming factors and mature microRNA-367/302 mimics. Also included are methods to assess reprogramming efficiency, expand clonal iPSC colonies, and confirm expression of the pluripotency marker TRA-1-60.

Induced pluripotent stem cells (iPSCs) have proven to be a valuable tool to study human development and disease. Further advancing iPSCs as a regenerative ...

Real-time Bioluminescence Imaging of Notch Signaling Dynamics during Murine Neurogenesis

Notch signaling regulates the maintenance of neural stem/progenitor cells by cell-cell interactions. The components of Notch signaling exhibit dynamic expression. Notch signaling effector Hes1 and the Notch ligand Delta-like1 (Dll1) are expressed in an oscillatory manner in neural stem/progenitor cells. Because the period of the oscillatory expression of these genes is very short (2 h), it is difficult to monitor their cyclic expression. To examine such rapid changes in the gene expression or protein dynamics, fast response reporters are required. Because of its fast maturation kinetics and high sensitivity, the bioluminescence reporter luciferase is suitable to monitor rapid gene expression changes in living cells. We used a destabilized luciferase reporter for monitoring the promoter activity and a luciferase-fused reporter for visualization of protein dynamics at single cell resolution. These bioluminescence reporters show rapid turnover and generate very weak signals; therefore, we have developed a highly sensitive bioluminescence imaging system to detect such faint signals. These methods enable us to monitor various gene expression dynamics in living cells and tissues, which are important information to help understand the actual cellular states.

Neural stem/progenitor cells exhibit various expression dynamics of Notch signaling components that lead to different outcomes of cellular events. Such dynamic expression can be revealed by real-time monitoring, not by static analysis, using a highly sensitive bioluminescence imaging system that enables visualization of rapid changes in gene expressions.

Notch signaling regulates the maintenance of neural stem/progenitor cells by cell-cell interactions. The components of Notch signaling exhibit dynamic ...

A Co-Culture Method to Study Neurite Outgrowth in Response to Dental Pulp Paracrine Signals

Tooth innervation allows teeth to sense pressure, temperature and inflammation, all of which are crucial to the use and maintenance of the tooth organ. Without sensory innervation, daily oral activities would cause irreparable damage. Despite its importance, the roles of innervation in tooth development and maintenance have been largely overlooked. Several studies have demonstrated that DP cells secrete extracellular matrix proteins and paracrine signals to attract and guide TG axons into and throughout the tooth. However, few studies have provided detailed insight into the crosstalk between the DP mesenchyme and neuronal afferents. To address this gap in knowledge, researchers have begun to utilize co-cultures and a variety of techniques to investigate these interactions. Here, we demonstrate the multiple steps involved in co-culturing primary DP cells with TG neurons dispersed on an overlying transwell filter with large diameter pores to allow axonal growth through the pores. Primary DP cells with the gene of interest flanked by loxP sites were utilized to facilitate gene deletion using an Adenovirus-Cre-GFP recombinase system. Using TG neurons from the Thy1-YFP mouse allowed for precise afferent imaging, with expression well above background levels by confocal microscopy. The DP responses can be investigated via protein or RNA collection and analysis, or alternatively, through immunofluorescent staining of DP cells plated on removable glass coverslips. Media can be analyzed using techniques such as proteomic analyses, although this will require albumin depletion due to the presence of fetal bovine serum in the media. This protocol provides a simple method that can be manipulated to study the morphological, genetic, and cytoskeletal responses of TG neurons and DP cells in response to the controlled environment of a co-culture assay.

We describe the isolation, dispersion and plating of dental pulp (DP) primary cells with trigeminal (TG) neurons cultured atop overlying transwell filters. Cellular responses of DP cells can be analyzed with immunofluorescence or RNA/protein analysis. Immunofluorescence of neuronal markers with confocal microscopy permits the analysis of neurite outgrowth responses.

Tooth innervation allows teeth to sense pressure, temperature and inflammation, all of which are crucial to the use and maintenance of the tooth organ. ...