Name: computed tomography and optical imaging of osteogenesis-angiogenesis coupling to assess integration of cranial bone autografts and allografts
Uploaded: 2015-12-22T13:00:00
Description: Watch this Scientific Journal Video about Computed Tomography and Optical Imaging of Osteogenesis-angiogenesis Coupling to Assess Integration of Cranial Bone Autografts and Allografts at JoVE.com

The authors acknowledge funding from the NIDCR (Grant No. DE019902) and from the Israeli Science Foundation (Grant No. 382/13).

The protocol follows the guidelines of the institutional animal care and use committee (IACUC) of The Hebrew University of Jerusalem, Israel (Request No. MD-12-13524-4), an AAALAC approved facility, and by the Cedars-Sinai Medical Center IACUC (Request No. 3770). The animals were treated in strict adherence to NIH guidelines.
1. Preparation of Bone Allografts
<ol>
	<li>Euthanize 7- to 8-week-old Balb/C mice, or any strain different from the recipient, using the standard method of CO2</s...

<ol>
	<li>Finkemeier, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone-grafting+and+bone-graft+substitutes.">Bone-grafting and bone-graft substitutes.</a> J Bone Joint Surg Am. 84-A (3), 454-464 (2002).</li><li>Kanczler, J. M., Oreffo, R. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Osteogenesis+and+angiogenesis:+the+potential+for+engineering+bone.">Osteogenesis and angiogenesis: the potential for engineering bone.</a> Eur Cell Mater. 15, 100-114 (2008).</li><li>Schipani, E., Maes, C., Carmeliet, G., Semenza, G. L. <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+osteogenesis-angiogenesis+coupling+by+HIFs+and+VEGF.">Regulation of osteogenesis-angiogenesis coupling by HIFs and VEGF.</a> J Bone Miner Res. 24 (8), 1347-1353 (2009).</li><li>Huang, 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=Spatiotemporal+Analyses+of+Osteogenesis+and+Angiogenesis+via+Intravital+Imaging+in+Cranial+Bone+Defect.">Spatiotemporal Analyses of Osteogenesis and Angiogenesis via Intravital Imaging in Cranial Bone Defect.</a> J Bone Miner Res. , (2015).</li><li>Kimelman-Bleich, 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=The+use+of+a+synthetic+oxygen+carrier-enriched+hydrogel+to+enhance+mesenchymal+stem+cell-based+bone+formation+in+vivo.">The use of a synthetic oxygen carrier-enriched hydrogel to enhance mesenchymal stem cell-based bone formation in vivo.</a> Biomaterials. 30 (27), 4639-4648 (2009).</li><li>Iris, 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=Molecular+imaging+of+the+skeleton:+quantitative+real-time+bioluminescence+monitoring+gene+expression+in+bone+repair+and+development.">Molecular imaging of the skeleton: quantitative real-time bioluminescence monitoring gene expression in bone repair and development.</a> J Bone Miner Res. 18 (3), 570-578 (2003).</li><li>Bouxsein, M. 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=Guidelines+for+assessment+of+bone+microstructure+in+rodents+using+micro-computed+tomography.">Guidelines for assessment of bone microstructure in rodents using micro-computed tomography.</a> J Bone Miner Res. 25 (7), 1468-1486 (2010).</li><li>Lim, E., Modi, K. D., Kim, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vivo+bioluminescent+imaging+of+mammary+tumors+using+IVIS+spectrum.">In vivo bioluminescent imaging of mammary tumors using IVIS spectrum.</a> J Vis Exp. (26), (2009).</li><li>Kallai, 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=Microcomputed+tomography-based+structural+analysis+of+various+bone+tissue+regeneration+models.">Microcomputed tomography-based structural analysis of various bone tissue regeneration models.</a> Nat Protoc. 6 (1), 105-110 (2011).</li><li>Fleming, J. 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=Bone+blood+flow+and+vascular+reactivity.">Bone blood flow and vascular reactivity.</a> Cells Tissues Organs. 169 (3), 279-284 (2001).</li><li>Dhillon, R. 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=PTH-enhanced+structural+allograft+healing+is+associated+with+decreased+angiopoietin-2-mediated+arteriogenesis,+mast+cell+accumulation,+and+fibrosis.">PTH-enhanced structural allograft healing is associated with decreased angiopoietin-2-mediated arteriogenesis, mast cell accumulation, and fibrosis.</a> J Bone Miner Res. 28 (3), 586-597 (2013).</li><li>Nebuloni, L., Kuhn, G. A., Vogel, J., Muller, R. A. <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+in+vivo+vascular+imaging+approach+for+hierarchical+quantification+of+vasculature+using+contrast+enhanced+micro-computed+tomography.">A novel in vivo vascular imaging approach for hierarchical quantification of vasculature using contrast enhanced micro-computed tomography.</a> PLoS One. 9 (1), e86562 (2014).</li><li>Zhang, 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=Periosteal+progenitor+cell+fate+in+segmental+cortical+bone+graft+transplantations:+implications+for+functional+tissue+engineering.">Periosteal progenitor cell fate in segmental cortical bone graft transplantations: implications for functional tissue engineering.</a> J Bone Miner Res. 20 (12), 2124-2137 (2005).</li><li>Movahed, R., Pinto, L. P., Morales-Ryan, C., Allen, W. R., Wolford, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+cranial+bone+grafts+for+reconstruction+of+maxillofacial+deformities.">Application of cranial bone grafts for reconstruction of maxillofacial deformities.</a> Proc (Bayl Univ Med Cent). 26 (3), 252-255 (2013).</li><li>Putters, T. F., Schortinghuis, J., Vissink, A., Raghoebar, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+prospective+study+on+the+morbidity+resulting+from+calvarial+bone+harvesting+for+intraoral+reconstruction.">A prospective study on the morbidity resulting from calvarial bone harvesting for intraoral reconstruction.</a> Int J Oral Maxillofac Surg. , (2015).</li><li>Kline, R. M., Wolfe, 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=Complications+associated+with+the+harvesting+of+cranial+bone+grafts.">Complications associated with the harvesting of cranial bone grafts.</a> Plast Reconstr Surg. 95 (1), 5-13 (1995).</li><li>Hassanein, A. 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=Effect+of+calvarial+burring+on+resorption+of+onlay+cranial+bone+graft.">Effect of calvarial burring on resorption of onlay cranial bone graft.</a> J Craniofac Surg. 23 (5), 1495-1498 (2012).</li><li>Yin, J., Jiang, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Completely+resorption+of+autologous+skull+flap+after+orthotopic+transplantation:+a+case+report.">Completely resorption of autologous skull flap after orthotopic transplantation: a case report.</a> Int J Clin Exp Med. 7 (4), 1169-1171 (2014).</li><li>Schuss, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone+flap+resorption:+risk+factors+for+the+development+of+a+long-term+complication+following+cranioplasty+after+decompressive+craniectomy.">Bone flap resorption: risk factors for the development of a long-term complication following cranioplasty after decompressive craniectomy.</a> J Neurotrauma. 30 (2), 91-95 (2013).</li><li>Ben Arav, 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=Adeno-associated+virus-coated+allografts:+a+novel+approach+for+cranioplasty.">Adeno-associated virus-coated allografts: a novel approach for cranioplasty.</a> J Tissue Eng Regen Med. 6 (10), e43-e50 (2012).</li><li>Ito, 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=Remodeling+of+cortical+bone+allografts+mediated+by+adherent+rAAV-RANKL+and+VEGF+gene+therapy.">Remodeling of cortical bone allografts mediated by adherent rAAV-RANKL and VEGF gene therapy.</a> Nat Med. 11 (3), 291-297 (2005).</li><li>Sheyn, 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=PTH+promotes+allograft+integration+in+a+calvarial+bone+defect.">PTH promotes allograft integration in a calvarial bone defect.</a> Mol Pharm. 10 (12), 4462-4471 (2013).</li><li>Jain, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+regulation+of+vessel+maturation.">Molecular regulation of vessel maturation.</a> Nat Med. 9 (6), 685-693 (2003).</li><li>Reginato, S., Gianni-Barrera, R., Banfi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Taming+of+the+wild+vessel:+promoting+vessel+stabilization+for+safe+therapeutic+angiogenesis.">Taming of the wild vessel: promoting vessel stabilization for safe therapeutic angiogenesis.</a> Biochem Soc Trans. 39 (6), 1654-1658 (2011).</li><li>Moutsatsos, I. 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=Exogenously+regulated+stem+cell-mediated+gene+therapy+for+bone+regeneration.">Exogenously regulated stem cell-mediated gene therapy for bone regeneration.</a> Mol Ther. 3 (4), 449-461 (2001).</li><li>Deckers, M. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone+morphogenetic+proteins+stimulate+angiogenesis+through+osteoblast-derived+vascular+endothelial+growth+factor.">Bone morphogenetic proteins stimulate angiogenesis through osteoblast-derived vascular endothelial growth factor.</a> A. Endocrinology. 143 (4), 1545-1553 (2002).</li><li>Cornejo, 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=Effect+of+adipose+tissue-derived+osteogenic+and+endothelial+cells+on+bone+allograft+osteogenesis+and+vascularization+in+critical-sized+calvarial+defects.">Effect of adipose tissue-derived osteogenic and endothelial cells on bone allograft osteogenesis and vascularization in critical-sized calvarial defects.</a> Tissue Eng Part A. 18 (15-16), 1552-1561 (2012).</li></ol>

The aim of the multimodal imaging approaches described here is to enable meticulous investigation of the angiogenesis-osteogenesis axis in the context of cranial bone grafting. Neovascularization was imaged using a &#181;CT protocol, which allowed an accurate high-resolution 3D demonstration of the vascular tree feeding the entire cranial defect. &#181;CT data can be readily analyzed using advanced tools such as IPL software. For example, the thickness analysis shown in Figure 3C revealed that the main d...

Craniofacial bone loss due to trauma, tumor resection, decompressive craniotomy, and congenital defect rarely heals by itself and presents a clear unmet clinical need. Autologous bone grafts and allogeneic bone grafts are extensively used to treat these conditions1.
It is widely accepted that osteogenesis is tightly coupled with angiogenesis2,3. Thus, the complete study of a proposed therapy for bone regeneration should include a comprehensive investigation of the vascular tree forming throughout the entire defect site. There are several available methods to characterize vascularization in research models. The vascular tree can be investigated by histological analysis. Since histology relies on sectioning tissue, there is a high probability that the resulting image will be distorted. To address this problem, intravital microscopy can be performed to image intact blood vessels4; however, this method is limited to one-plane imaging. &#181;CT scanning of specimens obtained from an animal perfused with contrast agent allows 3D imaging of the vascular network that feeds the regeneration site5. This approach allows a highly detailed demonstration of an organ&#8217;s vasculature as a whole, as well as a meticulous analysis of blood vessel distribution. Furthermore, &#181;CT enables differentiation between varied diameters of blood vessels, which characterize the different subtypes of blood vessels.
We hypothesized that implantation of a calvarial autograft will induce greater neovascularization than implantation of an allograft, and this increased neovascularization will lead, in turn, to enhanced bone formation.To pursue this hypothesis we employed a variety of techniques. We investigated patterns of the newly formed vascular tree by performing a &#181;CT-based analysis. We measured blood perfusion using a blood-pool fluorescent probe. Next, we assessed bone tissue mineralization by FLI of a hydroxyapatite-directed probe and &#181;CT analysis. Finally, we monitored stem cell recruitment and differentiation, performing BLI in transgenic mice in which luciferase is expressed in osteocalcin-positive cells.

<table border="0" cellpadding="0" cellspacing="0" width="614">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">C57BL/C&#160; Mice</td>
			<td style="width:112px;">Harlan laboratories</td>
			<td align="right" style="width:119px;">57</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">FVB/n Mice</td>
			<td style="width:112px;">Harlan laboratories</td>
			<td align="right" style="width:119px;">862</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Phenobarbital</td>
			<td style="width:112px;">West waro</td>
			<td style="width:119px;">NDC 0641-0477-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Rodent hair clipper</td>
			<td style="width:112px;">Wahl animal</td>
			<td style="width:119px;">8786-451A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Scalpel 11</td>
			<td style="width:112px;">Miltex</td>
			<td align="right" style="width:119px;">27111504</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Dental micro motor</td>
			<td style="width:112px;">marathon III</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">5mm trephine</td>
			<td style="width:112px;">Fine Science tools</td>
			<td style="width:119px;">18004-50</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Hair removing cream</td>
			<td style="width:112px;">Veet</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">KetaVed (Ketamine)</td>
			<td style="width:112px;">Vedco</td>
			<td style="width:119px;">NDC 50989-996-06</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Domitor</td>
			<td style="width:112px;">Zoetis</td>
			<td style="width:119px;">NADA 141-267</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">carprofen</td>
			<td style="width:112px;">Norbrook</td>
			<td style="width:119px;">02000/4229</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Eye ointment</td>
			<td style="width:112px;">Puralube</td>
			<td style="width:119px;">NDC 17033-211-38</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Operating binocular</td>
			<td style="width:112px;">Kent scientific</td>
			<td style="width:119px;">KSCXTS-1121</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Fine scissors&#160;</td>
			<td style="width:112px;">Fine Science tools</td>
			<td style="width:119px;">14060-11</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Curve tweezers</td>
			<td style="width:112px;">Fine Science tools</td>
			<td style="width:119px;">11274-20</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Spoon shaped spatula</td>
			<td style="width:112px;">Fine Science tools</td>
			<td style="width:119px;">10090-13</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Tisseel Fibin gel kit&#160;</td>
			<td style="width:112px;">Baxter</td>
			<td align="right" style="width:119px;">718971</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">needle holder</td>
			<td style="width:112px;">Fine Science tools</td>
			<td style="width:119px;">12060-01</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">vicryl suture 4-0</td>
			<td style="width:112px;">Ethicon</td>
			<td style="width:119px;">J392H</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Antisedan</td>
			<td style="width:112px;">Zoetis</td>
			<td style="width:119px;">NADA#141033</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Heparin</td>
			<td style="width:112px;">Sigma</td>
			<td style="width:119px;">H3393</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">20ml luerlock&#160;</td>
			<td style="width:112px;">BD</td>
			<td align="right" style="width:119px;">302830</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">23G scalp vein set (butterfly needle)</td>
			<td style="width:112px;">BD</td>
			<td align="right" style="width:119px;">367342</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hemostat</td>
			<td style="width:112px;">Fine Science tools</td>
			<td style="width:119px;">13008-12</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Syringe pump</td>
			<td style="width:112px;">Harvard apparatus</td>
			<td style="width:119px;">PHD 2000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">3sec gel glue&#160;</td>
			<td style="width:112px;">Scotch</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">rodent dissection board</td>
			<td style="width:112px;">Leica</td>
			<td style="width:119px;">38DI02313</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Microfil MV-122</td>
			<td style="width:112px;">flow-tech</td>
			<td style="width:119px;">MV-122</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">uCT40 scanner</td>
			<td style="width:112px;">Scanco</td>
			<td style="width:119px;">uCT40</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">TCA6%</td>
			<td style="width:112px;">Sigma</td>
			<td style="width:119px;">T6399</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Osteosense 680</td>
			<td style="width:112px;">PerkinElmar</td>
			<td style="width:119px;">NEV10020EX</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Angiosense750</td>
			<td style="width:112px;">PerkinElmar</td>
			<td style="width:119px;">NEV10011</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Oxigen 100% medical grade</td>
			<td style="width:112px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">isoflurane (furane)</td>
			<td style="width:112px;">Baxter</td>
			<td align="right" style="width:119px;">1001936040</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">IVIS kinetics</td>
			<td style="width:112px;">Xenogen</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Beetle luciferin</td>
			<td style="width:112px;">Promega</td>
			<td style="width:119px;">E160A</td>
			<td></td>
		</tr>
	</tbody>
</table>

computed tomography and optical imaging of osteogenesis-angiogenesis coupling to assess integration of cranial bone autografts and allografts

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that implantation of a bone autograft would induce greater bone regeneration by abundant blood vessel formation. To investigate the effect of the graft on neovascularization at the defect site, we developed a micro&#8211;computed tomography (&#181;CT) approach to characterize newly forming blood vessels, which involves systemic perfusion of the animal with a polymerizing contrast agent. This method enables detailed vascular analysis of an organ in its entirety. Additionally, blood perfusion was assessed using fluorescence imaging (FLI) of a blood-borne fluorescent agent. Bone formation was quantified by FLI using a hydroxyapatite-targeted probe and &#181;CT analysis. Stem cell recruitment was monitored by bioluminescence imaging (BLI) of transgenic mice that express luciferase under the control of the osteocalcin promoter. Here we describe and demonstrate preparation of the allograft, calvarial defect surgery, &#181;CT scanning protocols for the neovascularization study and bone formation analysis (including the in vivo perfusion of contrast agent), and the protocol for data analysis.
The 3D high-resolution analysis of vasculature demonstrated significantly greater angiogenesis in animals with implanted autografts, especially with respect to arteriole formation. Accordingly, blood perfusion was significantly higher in the autograft group by the 7th day after surgery. We observed superior bone mineralization and measured greater bone formation in animals that received autografts. Autograft implantation induced resident stem cell recruitment to the graft-host bone suture, where the cells differentiated into bone-forming cells between the 7th and 10th postoperative day. This finding means that enhanced bone formation may be attributed to the augmented vascular feeding that characterizes autograft implantation. The methods depicted may serve as an optimal tool to study bone regeneration in terms of tightly bounded bone formation and neovascularization.

Neovascularization was assessed by &#181;CT volumetric analysis and by FLI using a fluorescent blood-borne agent to quantify blood perfusion. Seven days after surgery, &#181;CT scanning demonstrated a significantly higher volume of small- and medium-diameter blood vessels in mice that had received autografts than in mice that had received allografts harvested from C57BL/6&#160;(Figure 3A). Interestingly, in the autograft group the newly formed vascular tree appeared to reach the entire defect area, where...

Watch this Scientific Journal Video about Computed Tomography and Optical Imaging of Osteogenesis-angiogenesis Coupling to Assess Integration of Cranial Bone Autografts and Allografts at JoVE.com

Computed Tomography and Optical Imaging of Osteogenesis-angiogenesis Coupling to Assess Integration of Cranial Bone Autografts and Allografts

Implantation of autologous and allogeneic bone grafts constitute accepted approaches to treat major craniofacial bone loss. Yet the effect of graft composition on the interplay among neovascularization, cell differentiation and bone formation is unclear. We present a multimodal imaging protocol aimed to elucidate the angiogenesis-osteogenesis interdependence at the graft proximity.

A major parameter determining the success of a bone-grafting procedure is vascularization of the area surrounding the graft. We hypothesized that ...

Research

JoVE Journal

Bioengineering

Three-dimensional Optical-resolution Photoacoustic Microscopy

Optical microscopy, providing valuable insights at the cellular and organelle levels, has been widely recognized as an enabling biomedical technology. As ...

Attaching Biological Probes to Silica Optical Biosensors Using Silane Coupling Agents

In order to interface with biological environments, biosensor platforms, such as the popular Biacore system (based on the Surface Plasmon Resonance (SPR) ...

Integrated Photoacoustic Ophthalmoscopy and Spectral-domain Optical Coherence Tomography

Both the clinical diagnosis and fundamental investigation of major ocular diseases greatly benefit from various non-invasive ophthalmic imaging ...

Wideband Optical Detector of Ultrasound for Medical Imaging Applications

Optical sensors of ultrasound are a promising alternative to piezoelectric techniques, as has been recently demonstrated in the field of optoacoustic ...

An Improved Mechanical Testing Method to Assess Bone-implant Anchorage

Recent advances in material science have led to a substantial increase in the topographical complexity of implant surfaces, both on a micro- and a ...

In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography

In Vivo Quantitative Assessment of Myocardial Structure, Function, Perfusion and Viability Using Cardiac Micro-computed Tomography

The use of Micro-Computed Tomography (MicroCT) for in vivo studies of small animals as models of human disease has risen tremendously due to the fact that ...

Proper Positioning and Restraint of a Rat Hind Limb for Focused High Resolution Imaging of Bone Micro-architecture Using In Vivo Micro-computed Tomography

Proper Positioning and Restraint of a Rat Hind Limb for Focused High Resolution Imaging of Bone Micro-architecture Using In Vivo Micro-computed Tomography

The use of in vivo micro-computed tomography (&#181;CT) is a powerful tool which involves the non-destructive imaging of internal structures at high ...

Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy (oSLO) and Optical Coherence Tomography (OCT)

Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy oSLO and Optical Coherence Tomography OCT

While fluorescence imaging is widely used in ophthalmology, a large field of view (FOV) three-dimensional (3D) fluorescence retinal image is still a big ...

Use of Micro X-ray Computed Tomography with Phosphotungstic Acid Preparation to Visualize Human Fibromuscular Tissue

Manual dissection and histological observation are common methods used to investigate human tissues. However, manual dissection can damage delicate ...

Optical Imaging of Isolated Murine Ventricular Myocytes

The ability to isolate adult cardiac myocytes has permitted researchers to study a variety of cardiac pathologies at the single cell level. While advances ...