Name: creating anatomically accurate and reproducible intracranial xenografts of human brain tumors
Uploaded: 2014-09-24T15:00:00
Description: Watch this Scientific Journal Video about Creating Anatomically Accurate and Reproducible Intracranial Xenografts of Human Brain Tumors at JoVE.com

Dr. Keating is funded by DOD grant CA100335 and is a St. Baldrick&#8217;s Foundation Scholar.

All described procedures were reviewed and approved by our institutional animal care and use committee.
1. Plan the Experiment
<ol>
	<li>Choose cells to be injected. Cells from a variety of sources are candidates for injection: adherent cell culture lines, genetically modified clones, neurosphere cells, primary cultures, or disaggregated tumors. The type of model desired will define the most appropriate site of injection.
	<ol>
		<li>Determine cell number for injection. The number of cells r...

<ol>
	<li>Heyer, J., Kwong, L. N., Lowe, S. W., Chin, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-germline+genetically+engineered+mouse+models+for+translational+cancer+research.">Non-germline genetically engineered mouse models for translational cancer research.</a> Nature reviews. Cancer. 10, 470-480 (2010).</li><li>Yamada, 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=A+method+to+accurately+inject+tumor+cells+into+the+caudate/putamen+nuclei+of+the+mouse+brain.">A method to accurately inject tumor cells into the caudate/putamen nuclei of the mouse brain.</a> The Tokai journal of experimental and clinical medicine. 29, 167-173 (2004).</li><li>Brooks, A. 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=Reproducible+and+efficient+murine+CNS+gene+delivery+using+a+microprocessor-controlled+injector.">Reproducible and efficient murine CNS gene delivery using a microprocessor-controlled injector.</a> Journal of neuroscience. 80, 137-147 (1998).</li><li>Shankavaram, U. 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=Molecular+profiling+indicates+orthotopic+xenograft+of+glioma+cell+lines+simulate+a+subclass+of+human+glioblastoma.">Molecular profiling indicates orthotopic xenograft of glioma cell lines simulate a subclass of human glioblastoma.</a> Journal of cellular and molecular medicine. 16, 545-554 (2012).</li><li>Giannini, 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=Patient+tumor+EGFR+and+PDGFRA+gene+amplifications+retained+in+an+invasive+intracranial+xenograft+model+of+glioblastoma+multiforme.">Patient tumor EGFR and PDGFRA gene amplifications retained in an invasive intracranial xenograft model of glioblastoma multiforme.</a> Neuro-oncology. 7, 164-176 (2005).</li><li>Yi, D., Hua, T. X., Lin, H. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EGFR+gene+overexpression+retained+in+an+invasive+xenograft+model+by+solid+orthotopic+transplantation+of+human+glioblastoma+multiforme+into+nude+mice.">EGFR gene overexpression retained in an invasive xenograft model by solid orthotopic transplantation of human glioblastoma multiforme into nude mice.</a> Cancer investigation. 29, 229-239 (2011).</li><li>Carty, 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=Intracranial+injection+of+AAV+expressing+NEP+but+not+IDE+reduces+amyloid+pathology+in+APP+PS1+transgenic+mice.">Intracranial injection of AAV expressing NEP but not IDE reduces amyloid pathology in APP+PS1 transgenic mice.</a> PLos ONE. 8, e59626 (2013).</li><li>Thaci, 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=Pharmacokinetic+study+of+neural+stem+cell-based+cell+carrier+for+oncolytic+virotherapy:+targeted+delivery+of+the+therapeutic+payload+in+an+orthotopic+brain+tumor+model.">Pharmacokinetic study of neural stem cell-based cell carrier for oncolytic virotherapy: targeted delivery of the therapeutic payload in an orthotopic brain tumor model.</a> Cancer gene therapy. 19, 431-442 (2012).</li><li>Ozawa, T., James, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishing+intracranial+brain+tumor+xenografts+with+subsequent+analysis+of+tumor+growth+and+response+to+therapy+using+bioluminescence+imaging.">Establishing intracranial brain tumor xenografts with subsequent analysis of tumor growth and response to therapy using bioluminescence imaging.</a> J. Vis. Exp. (41), (2010).</li><li>Valadez, J. G., Sarangi, A., Lundberg, C. J., Cooper, M. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Primary+orthotopic+glioma+xenografts+recapitulate+infiltrative+growth+and+isocitrate+dehydrogenase+I+mutation.">Primary orthotopic glioma xenografts recapitulate infiltrative growth and isocitrate dehydrogenase I mutation.</a> J. Vis. Exp. (83), (2014).</li><li>Baumann, B. C., Dorsey, J. F., Benci, J. L., Joh, D. Y., Kao, G. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stereotactic+intracranial+implantation+and+in+vivo+bioluminescent+imaging+of+tumor+xenografts+in+a+mouse+model+system+of+glioblastoma+multiforme.">Stereotactic intracranial implantation and in vivo bioluminescent imaging of tumor xenografts in a mouse model system of glioblastoma multiforme.</a> J. Vis. Exp. (67), (2012).</li><li>Iwami, 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=A+novel+method+of+intracranial+injection+via+the+postglenoid+foramen+for+brain+tumor+mouse+models.">A novel method of intracranial injection via the postglenoid foramen for brain tumor mouse models.</a> Journal of neurosurgery. 116, 630-635 (2012).</li></ol>

Orthotopic mouse models of human brain cancer can be an excellent tool for assessing the effectiveness of clinical therapies, but care must be taken to optimize the placement of cells in brain tissue. Studies have shown that excessive aliquot volumes, suboptimal injection technique and hasty injection rates can lead to leakiness and the appearance of tumor cells in undesirable locations (ventricles, spinal cord, extradural regions, etc.) and high variation in tumor size2 (personal observations). An an...

In vitro studies of brain tumor cells are invaluable for dissecting molecular mechanisms driving growth, survival, migration, and invasion of cancer cells; cultured cell experiments can define signaling pathways, suggest potential therapeutic targets, and characterize cellular response to drug treatment. But in vitro systems are far too simplistic to predict organismal response to pharmaceuticals; they lack the physiological reactions, immune responses, cell microenvironment, and overall heterogeneity of living animal systems. Genetically engineered models can be invaluable, when available, but molecular differences exist between species and murine cells may not recapitulate events in human processes, resulting in significant discrepancies when comparing animal models to clinical observations1. Mouse xenograft models involving subcutaneous (SQ) injection of human brain tumor cell lines under the skin of the flank are easy to perform and measure; they can be used to address effects of gene modification and drug administration/delivery, metabolism and toxicity. Significant drawbacks, however, limit the utility of SQ models. The microenvironment does not recapitulate that of a naturally occurring brain tumor: the interactions of various cell types and tissues; the local vasculature, and myriad other factors unique to the brain cannot be replicated. To more accurately reproduce the unique milieu of a naturally occurring brain tumor and test the effects of pharmaceutical interventions, a mouse orthotopic model should be utilized. Furthermore, orthotopic techniques may be used as part of a genetically engineered approach in which human primary non-cancerous cells (differentiated or progenitor) are genetically modified and injected into the relevant site of a mouse, with or without human stroma cells, resulting in tumorigenesis similar to that seen in humans1.
This article describes a methodology to precisely and reproducibly create brain tumors in mice. Using this technique, the user can accurately inject a small aliquot of suspended cells into a specified location of the fronto-parieto-temporal region of the mouse cerebral cortex. Mouse mortality is extremely low; in our hands, no mice have died from surgical complications after 185 procedures. Characteristics of the resultant tumor can be compared with that of typical human clinical tumors; for example: rapidity of growth, degree of necrosis, extent of invasion, heterogeneity of cell type, presence of mitotic cells, markers of proliferation and apoptosis, etc. Cell lines or disaggregated human tissue or tumor samples can then be evaluated based on their ability to simulate actual clinical presentation. Pharmaceuticals, selected based on their performance in cell culture, can be tested in the context of a functioning metabolism, circulatory system, and blood-brain barrier as they exist in an animal burdened with a tumor, all in a relevant architectural context. Furthermore, the cells chosen for injection may be genetically modified to investigate the impact of specific knockdowns, deletions, knock-ins, mutations, etc. on tumor growth and survival.
A number of publications document tumors studies using a variety of intracranial techniques. Yamada et al. did a detailed study of the injection of dye and of U87 cells and found that minimizing volume and injection rate produced the best tumor2. Brooks et al. found superior reproducibility and efficiency using a microprocessor-controlled injector rather than a manual method to deliver viral vectors; their conclusions regarding optimal injection parameters are applicable to cell delivery3. Shankavaram et al. showed that glioblastoma multiforme (GBM) cell lines injected orthotopically (using a manual method) into the brain recapitulated the gene expression profile of the clinical tumors more closely than either in vitro or SQ xenografts, supporting the use of intracranial models for preclinical studies4. Giannini et al. injected cells from human surgical specimens that had been sustained in the flanks of nude mice by serial passaging into the brains of additional mice, and showed that this approach preserved patient tumor gene alterations in the model5. Similar results were reported by Yi et al6. Using a stereotaxic setup, carefully defined injection site, and a slow and steady injection rate, they obtained reproducible brain tumors with consistent growth rates and high (100%) engraftment rate. The validity of this technique has therefore been well established; a literature search suggests that the applications of this technique are extensive. Carty et al. used intracranial injections to successfully deliver viral vectors expressing therapeutic genes into the frontal cortex of transgenic model of Alzheimer&#8217;s disease7. Thaci et al. described the use of intracranial injections to deliver therapeutic oncolytic adenovirus in a neural stem cell based carrier into nude mice already carrying orthotopically injected GBM tumors8. Clearly, intracranial injections are a versatile and effective tool for preclinical research. Earlier publications in The Journal of Visualized Experiments describe fundamental approaches9-11, but we take the concept of intracranial tumor injection and orthotopic modeling to a higher level of precision using easy-to-master technology.

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			<td height="21" style="height:21px;width:349px;">Name of Reagent/ Equipment</td>
			<td style="width:87px;">Company</td>
			<td style="width:145px;">Catalog Number</td>
			<td style="width:287px;">Comments/Description</td>
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			<td height="21" style="height:21px;width:349px;">Equipment</td>
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			<td height="42" style="height:42px;width:349px;">Small Animal Stereotaxic Instrument with Digital Display Console.</td>
			<td style="width:87px;">Kopf</td>
			<td style="width:145px;">Model 940</td>
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			<td height="21" style="height:21px;width:349px;">Mouse Gas Anesthesia Head Holder</td>
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			<td style="width:145px;">Model 923-B</td>
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			<td height="21" style="height:21px;width:349px;">Mouse Ear Bars</td>
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			<td style="width:145px;">Medel 922</td>
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			<td height="21" style="height:21px;width:349px;">Fiber Optic Illuminator</td>
			<td style="width:87px;">Fisher</td>
			<td style="width:145px;">12-562-36</td>
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			<td height="21" style="height:21px;width:349px;">UltraMicroPump III</td>
			<td style="width:87px;">WPI</td>
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			<td height="21" style="height:21px;width:349px;">Micro4 microprocessor</td>
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			<td height="21" style="height:21px;width:349px;">Variable speed hand-held rotary drill</td>
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			<td style="width:145px;">Model 300</td>
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			<td height="21" style="height:21px;width:349px;">Dental drill bit, 1.0 mm</td>
			<td style="width:87px;">Spoelting</td>
			<td style="width:145px;">514554</td>
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			<td height="21" style="height:21px;width:349px;">Adaptor for dental drill bit: 3/32 inch collet</td>
			<td style="width:87px;">Dremel</td>
			<td style="width:145px;">481</td>
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			<td height="21" style="height:21px;width:349px;">Heating pad</td>
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			<td>for mice</td>
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			<td height="21" style="height:21px;width:349px;">Isoflurane vaporizer system</td>
			<td style="width:87px;"></td>
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			<td>for mice</td>
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			<td style="width:287px;">to connect isoflurane vaporizer with stereotaxic frame</td>
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			<td height="21" style="height:21px;width:349px;">Instruments</td>
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			<td height="21" style="height:21px;width:349px;">Precision 25 ul micro syringe</td>
			<td style="width:87px;">Hamilton&#160;</td>
			<td style="width:145px;">7636-01</td>
			<td>Model 702, without needle</td>
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			<td height="21" style="height:21px;width:349px;">Microsyringe needles, 26s gauge&#160;</td>
			<td style="width:87px;">Hamilton&#160;</td>
			<td style="width:145px;">7804-04</td>
			<td>RN, 25 mm point style 2</td>
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			<td height="21" style="height:21px;width:349px;">Fine-tipped scissors (straight, sharp/sharp)</td>
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			<td height="21" style="height:21px;width:349px;">Medium-sized standard scissors</td>
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			<td height="21" style="height:21px;width:349px;">Standard serrated forceps</td>
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			<td style="width:145px;"></td>
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			<td height="21" style="height:21px;width:349px;">Serrated hemostats (2)</td>
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			<td style="width:145px;"></td>
			<td></td>
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			<td height="21" style="height:21px;width:349px;">Fine-tipped forceps</td>
			<td style="width:87px;"></td>
			<td style="width:145px;"></td>
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			<td height="21" style="height:21px;width:349px;">Supplies</td>
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			<td height="21" style="height:21px;width:349px;">Sutures 5-0 vicryl P-3 13 mm (Ethicon)</td>
			<td style="width:87px;">MWI</td>
			<td style="width:145px;">J463G</td>
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			<td height="21" style="height:21px;width:349px;">Surgical blades #10, stainless (Feather)</td>
			<td style="width:87px;">Fisher</td>
			<td style="width:145px;">296#10</td>
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			<td height="84" style="height:84px;width:349px;">Isoflurane (Fluriso)&#160;</td>
			<td style="width:87px;">VetOne&#160;</td>
			<td style="width:145px;">NDC 13985-528-60</td>
			<td style="width:287px;">Item #502017. Liquid inhalation anesthetic. federal law restricts this drug to use by or on the order of a licensed veterinarian.</td>
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			<td height="21" style="height:21px;width:349px;">Carprofen (Rimadyl Injectable 50 mg/mL)&#160;</td>
			<td style="width:87px;">Pfizer</td>
			<td style="width:145px;">NDC 61106-8507-01</td>
			<td>dilute in saline</td>
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			<td height="21" style="height:21px;width:349px;">Ophthalmic ointment (artificial tears)</td>
			<td style="width:87px;">Rugby</td>
			<td style="width:145px;">NDC 0536-6550-91</td>
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			<td height="21" style="height:21px;width:349px;">Topical antibiotic (AK-Poly-Bac )</td>
			<td style="width:87px;">Akorn</td>
			<td style="width:145px;">NDC 17478-238-35</td>
			<td></td>
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			<td height="21" style="height:21px;width:349px;">Povidone-iodine topical antiseptic, 10% (Betadine)</td>
			<td style="width:87px;">Betadine</td>
			<td style="width:145px;">NDC 67618-150-04</td>
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			<td height="21" style="height:21px;width:349px;">Hydrogen Peroxide, 30%</td>
			<td style="width:87px;">Fisher&#160;</td>
			<td style="width:145px;">H325-100</td>
			<td>for visualizing skull landmarks</td>
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			<td height="21" style="height:21px;width:349px;">Sterile saline</td>
			<td style="width:87px;">VetOne&#160;&#160;</td>
			<td style="width:145px;">NDC 13985-807-25</td>
			<td>for diluting solutions, cleaning tissue</td>
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		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Bone wax</td>
			<td style="width:87px;">WPI</td>
			<td style="width:145px;">Item #501771</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Sterile drapes</td>
			<td style="width:87px;">McKesson</td>
			<td style="width:145px;">25-517</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Sterile surgical gloves</td>
			<td style="width:87px;">McKesson</td>
			<td style="width:145px;">(to fit)</td>
			<td></td>
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		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Sterile gauze pads, 2 x 2</td>
			<td style="width:87px;">Fisherbrand&#160;</td>
			<td style="width:145px;">22028556</td>
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		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Sterile gauze pads, 4 x 4</td>
			<td style="width:87px;">Fisherbrand&#160;</td>
			<td style="width:145px;">22-415-469</td>
			<td></td>
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			<td height="21" style="height:21px;width:349px;">Alcohol prep pads (medium)</td>
			<td style="width:87px;">PDI</td>
			<td style="width:145px;">B603</td>
			<td></td>
		</tr>
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			<td height="21" style="height:21px;width:349px;">Sterile cotton-tipped applicators</td>
			<td style="width:87px;">Fisherbrand&#160;</td>
			<td style="width:145px;">23-400-114</td>
			<td></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:349px;">Sterile 0.5 ml screw cap tube with caps for cells</td>
			<td style="width:87px;">USA Scientific</td>
			<td style="width:145px;">1405-4700</td>
			<td>for cells</td>
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		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Individually wrapped sterile dispo pipettes</td>
			<td style="width:87px;">Fisher</td>
			<td style="width:145px;">BD 357575</td>
			<td>for needle cleaning solutions</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:349px;">BD insulin syringes with needles&#160;</td>
			<td style="width:87px;">Fisher</td>
			<td style="width:145px;">329461</td>
			<td>for analgesic</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:349px;">70% ethanol</td>
			<td style="width:87px;"></td>
			<td style="width:145px;"></td>
			<td>for cleaning</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:349px;">Sterile di H2O</td>
			<td style="width:87px;"></td>
			<td style="width:145px;"></td>
			<td>for cleaning</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Microfuge tubes for cleaning solutions</td>
			<td style="width:87px;"></td>
			<td style="width:145px;"></td>
			<td>for needle cleaning solutions</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:349px;">Felt tip pen (dedicated)</td>
			<td style="width:87px;"></td>
			<td style="width:145px;"></td>
			<td>for marking skull</td>
		</tr>
	</tbody>
</table>

creating anatomically accurate and reproducible intracranial xenografts of human brain tumors

Orthotopic tumor models are currently the best way to study the characteristics of a tumor type, with and without intervention, in the context of a live animal &#8211;&#160;particularly in sites with unique physiological and architectural qualities such as the brain. In vitro and ectopic models cannot account for features such as vasculature, blood brain barrier, metabolism, drug delivery and toxicity, and a host of other relevant factors. Orthotopic models have their limitations too, but with proper technique tumor cells of interest can be accurately engrafted into tissue that most closely mimics conditions in the human brain. By employing methods that deliver precisely measured volumes to accurately defined locations at a consistent rate and pressure, mouse models of human brain tumors with predictable growth rates can be reproducibly created and are suitable for reliable analysis of various interventions. The protocol described here focuses on the technical details of designing and preparing for an intracranial injection, performing the surgery, and ensuring successful and reproducible tumor growth and provides starting points for a variety of conditions that can be customized for a range of different brain tumor models.

Reliable intracranial xenografts can be created with this described technique. Identifying the critical structures of the mouse skull (Figure 1) will allow for recognition of the bregma and guide the investigator to a precise and reproducible injection location. In these studies the U251 parental line, U251 cells transfected with luciferase (U251-Luc), or U87 immortalized human GBM tissue culture cells were suspended in 4 to 6 &#181;l of SF-DMEM and injected 2.5 mm lateral (right), 1.5 mm anterior, and 3...

Watch this Scientific Journal Video about Creating Anatomically Accurate and Reproducible Intracranial Xenografts of Human Brain Tumors at JoVE.com

Creating Anatomically Accurate and Reproducible Intracranial Xenografts of Human Brain Tumors

The brain is a unique site with qualities that are not well represented by in vitro or ectopic analyses. Orthotopic mouse models with reproducible location and growth characteristics can be reliably created with intracranial injections using a stereotaxic fixation instrument and a low pressure syringe pump.

Orthotopic tumor models are currently the best way to study the characteristics of a tumor type, with and without intervention, in the context of a live ...

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Research

JoVE Journal

Medicine

Establishment and Propagation of Human Retinoblastoma Tumors in Immune Deficient Mice

Culturing retinoblastoma tumor cells in defined stem cell media gives rise to primary tumorspheres that can be grown and maintained for only a limited time. These cultured tumorspheres may exhibit markedly different cellular phenotypes when compared to the original tumors. Demonstration that cultured cells have the capability of forming new tumors is important to ensure that cultured cells model the biology of the original tumor. 
Here we present a protocol for propagating human retinoblastoma tumors in vivo using Rag2-/- immune deficient mice. Cultured human retinoblastoma tumorspheres of low passage or cells obtained from freshly harvested human retinoblastoma tumors injected directly into the vitreous cavity of murine eyes form tumors within 2-4 weeks. These tumors can be harvested and either further passaged into murine eyes in vivo or grown as tumorspheres in vitro. Propagation has been successfully carried out for at least three passages thus establishing a continuing source of human retinoblastoma tissue for further experimentation. 
Wesley S. Bond and Lalita Wadhwa are co-first authors.

A method is described to propagate human retinoblastoma tumors in mice. Tumor cells are directly injected into the eyes of immune deficient mice. Secondary tumors have been successfully established using both cells directly harvested from human tumors and cultured tumorspheres.

Culturing retinoblastoma tumor cells in defined stem cell media gives rise to primary tumorspheres that can be grown and maintained for only a limited ...

Automated Midline Shift and Intracranial Pressure Estimation based on Brain CT Images

In this paper we present an automated system based mainly on the computed tomography (CT) images consisting of two main components: the midline shift estimation and intracranial pressure (ICP) pre-screening system. To estimate the midline shift, first an estimation of the ideal midline is performed based on the symmetry of the skull and anatomical features in the brain CT scan. Then, segmentation of the ventricles from the CT scan is performed and used as a guide for the identification of the actual midline through shape matching. These processes mimic the measuring process by physicians and have shown promising results in the evaluation. In the second component, more features are extracted related to ICP, such as the texture information, blood amount from CT scans and other recorded features, such as age, injury severity score to estimate the ICP are also incorporated. Machine learning techniques including feature selection and classification, such as Support Vector Machines (SVMs), are employed to build the prediction model using RapidMiner. The evaluation of the prediction shows potential usefulness of the model. The estimated ideal midline shift and predicted ICP levels may be used as a fast pre-screening step for physicians to make decisions, so as to recommend for or against invasive ICP monitoring.

An automated midline shift estimation and intracranial pressure (ICP) pre-screening system based on computed tomography (CT) images for patients with traumatic brain injury (TBI) is proposed using image processing and machine learning techniques.

In this paper we present an automated system based mainly on the computed tomography (CT) images consisting of two main components: the midline shift ...

Stereotactic Intracranial Implantation and In vivo Bioluminescent Imaging of Tumor Xenografts in a Mouse Model System of Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is a high-grade primary brain cancer with a median survival of only 14.6 months in humans despite standard tri-modality treatment consisting of surgical resection, post-operative radiation therapy and temozolomide chemotherapy 1. New therapeutic approaches are clearly needed to improve patient survival and quality of life. The development of more effective treatment strategies would be aided by animal models of GBM that recapitulate human disease yet allow serial imaging to monitor tumor growth and treatment response. In this paper, we describe our technique for the precise stereotactic implantation of bio-imageable GBM cancer cells into the brains of nude mice resulting in tumor xenografts that recapitulate key clinical features of GBM 2. This method yields tumors that are reproducible and are located in precise anatomic locations while allowing in vivo bioluminescent imaging to serially monitor intracranial xenograft growth and response to treatments 3-5. This method is also well-tolerated by the animals with low perioperative morbidity and mortality.

Stereotactic Intracranial Implantation and In vivo Bioluminescent Imaging of Tumor Xenografts in a Mouse Model System of Glioblastoma Multiforme

We describe an integrated method for the precise, stereotactic implantation of human glioblastoma multiforme cells into the brains of nude mice and subsequent serial in vivo imaging to monitor growth and response to treatment of the resultant xenografts.

Glioblastoma multiforme (GBM) is a high-grade primary brain cancer with a median survival of only 14.6 months in humans despite standard tri-modality ...

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

We have successfully integrated previously established Intracranial window (ICW) technology 1-4 with intravital 2-photon confocal microscopy to develop a novel platform that allows for direct long-term visualization of tissue structure changes intracranially. Imaging at a single cell resolution in a real-time fashion provides supplementary dynamic information beyond that provided by standard end-point histological analysis, which looks solely at 'snap-shot' cross sections of tissue.
Establishing this intravital imaging technique in fluorescent chimeric mice, we are able to image four fluorescent channels simultaneously. By incorporating fluorescently labeled cells, such as GFP+ bone marrow, it is possible to track the fate of these cells studying their long-term migration, integration and differentiation within tissue. Further integration of a secondary reporter cell, such as an mCherry glioma tumor line, allows for characterization of cell:cell interactions. Structural changes in the tissue microenvironment can be highlighted through the addition of intra-vital dyes and antibodies, for example CD31 tagged antibodies and Dextran molecules.
Moreover, we describe the combination of our ICW imaging model with a small animal micro-irradiator that provides stereotactic irradiation, creating a platform through which the dynamic tissue changes that occur following the administration of ionizing irradiation can be assessed.
Current limitations of our model include penetrance of the microscope, which is limited to a depth of up to 900 &mu;m from the sub cortical surface, limiting imaging to the dorsal axis of the brain. The presence of the skull bone makes the ICW a more challenging technical procedure, compared to the more established and utilized chamber models currently used to study mammary tissue and fat pads 5-7. In addition, the ICW provides many challenges when optimizing the imaging.

A Novel High-resolution In vivo Imaging Technique to Study the Dynamic Response of Intracranial Structures to Tumor Growth and Therapeutics

We describe a novel in vivo imaging technique that couples fluorescent chimeric mice with intracranial windows and high-resolution 2-photon microscopy. This imaging platform aids studies of dynamic changes in brain tissue and microvasculature, at a single-cell level, following pathological insults and is adaptable to assess intracranial drug delivery and distribution.

We have successfully integrated previously established Intracranial window (ICW) technology 1-4 with intravital 2-photon confocal microscopy to develop a ...

Generation of Subcutaneous and Intrahepatic Human Hepatocellular Carcinoma Xenografts in Immunodeficient Mice

In vivo experimental models of hepatocellular carcinoma (HCC) that recapitulate the human disease provide a valuable platform for research into disease pathophysiology and for the preclinical evaluation of novel therapies. We present a variety of methods to generate subcutaneous or orthotopic human HCC xenografts in immunodeficient mice that could be utilized in a variety of research applications. With a focus on the use of primary tumor tissue from patients undergoing surgical resection as a starting point, we describe the preparation of cell suspensions or tumor fragments for xenografting. We describe specific techniques to xenograft these tissues i) subcutaneously; or ii) intrahepatically, either by direct implantation of tumor cells or fragments into the liver, or indirectly by injection of cells into the mouse spleen. We also describe the use of partial resection of the native mouse liver at the time of xenografting as a strategy to induce a state of active liver regeneration in the recipient mouse that may facilitate the intrahepatic engraftment of primary human tumor cells. The expected results of these techniques are illustrated. The protocols described have been validated using primary human HCC samples and xenografts, which typically perform less robustly than the well-established human HCC cell lines that are widely used and frequently cited in the literature. In comparison with cell lines, we discuss factors which may contribute to the relatively low chance of primary HCC engraftment in xenotransplantation models and comment on technical issues that may influence the kinetics of xenograft growth. We also suggest methods that should be applied to ensure that xenografts obtained accurately resemble parent HCC tissues.

Human tumor xenografts in immunodeficient mice are valuable tools to study cancer biology. Specific protocols to generate subcutaneous and intrahepatic xenografts from human hepatocellular carcinoma cells or tumor fragments are described. Liver regeneration induced by partial hepatectomy in recipient mice is presented as a strategy to facilitate intrahepatic engraftment.

In  vivo experimental models of hepatocellular carcinoma (HCC) that recapitulate  the human disease provide a valuable platform for research into disease  ...

Lesion Explorer: A Video-guided, Standardized Protocol for Accurate and Reliable MRI-derived Volumetrics in Alzheimer's Disease and Normal Elderly

Obtaining in vivo human brain tissue volumetrics from MRI is often complicated by various technical and biological issues. These challenges are exacerbated when significant brain atrophy and age-related white matter changes (e.g. Leukoaraiosis) are present. Lesion Explorer (LE) is an accurate and reliable neuroimaging pipeline specifically developed to address such issues commonly observed on MRI of Alzheimer's disease and normal elderly. The pipeline is a complex set of semi-automatic procedures which has been previously validated in a series of internal and external reliability tests1,2. However, LE's accuracy and reliability is highly dependent on properly trained manual operators to execute commands, identify distinct anatomical landmarks, and manually edit/verify various computer-generated segmentation outputs.
LE can be divided into 3 main components, each requiring a set of commands and manual operations: 1) Brain-Sizer, 2) SABRE, and 3) Lesion-Seg. Brain-Sizer's manual operations involve editing of the automatic skull-stripped total intracranial vault (TIV) extraction mask, designation of ventricular cerebrospinal fluid (vCSF), and removal of subtentorial structures. The SABRE component requires checking of image alignment along the anterior and posterior commissure (ACPC) plane, and identification of several anatomical landmarks required for regional parcellation. Finally, the Lesion-Seg component involves manual checking of the automatic lesion segmentation of subcortical hyperintensities (SH) for false positive errors.
While on-site training of the LE pipeline is preferable, readily available visual teaching tools with interactive training images are a viable alternative. Developed to ensure a high degree of accuracy and reliability, the following is a step-by-step, video-guided, standardized protocol for LE's manual procedures.

Lesion Explorer: A Video-guided, Standardized Protocol for Accurate and Reliable MRI-derived Volumetrics in Alzheimer&#039;s Disease and Normal Elderly

Lesion Explorer (LE) is a semi-automatic, image-processing pipeline developed to obtain regional brain tissue and subcortical hyperintensity lesion volumetrics from structural MRI of Alzheimer's disease and normal elderly. To ensure a high level of accuracy and reliability, the following is a video-guided, standardized protocol for LE's manual procedures.

Obtaining in vivo human brain tissue volumetrics from MRI is often complicated by various technical and biological issues. These challenges are ...

Minimally Invasive Establishment of Murine Orthotopic Bladder Xenografts

Orthotopic bladder cancer xenografts are the gold standard to study molecular cellular manipulations and new therapeutic agents&#160;in vivo. Suitable cell lines are inoculated either by intravesical instillation (model of nonmuscle invasive growth) or intramural injection into the bladder wall (model of invasive growth). Both procedures are complex and highly time-consuming. Additionally, the superficial model has its shortcomings due to the lack of cell lines that are tumorigenic following instillation. Intramural injection, on the other hand, is marred by the invasiveness of the procedure and the associated morbidity for the host mouse.
With these shortcomings in mind, we modified previous methods to develop a minimally invasive approach for creating orthotopic bladder cancer xenografts. Using ultrasound guidance we have successfully performed percutaneous inoculation of the bladder cancer cell lines UM-UC1, UM-UC3 and UM-UC13 into 50 athymic nude. We have been able to demonstrate that this approach is time efficient, precise and safe. With this technique, initially a space is created under the bladder mucosa with PBS, and tumor cells are then injected into this space in a second step. Tumor growth is monitored at regular intervals with bioluminescence imaging and ultrasound. The average tumor volumes increased steadily in in all but one of our 50 mice over the study period.
In our institution, this novel approach, which allows bladder cancer xenograft inoculation in a minimally-invasive, rapid and highly precise way, has replaced the traditional model.

The established technique to inoculate primary invasive orthotopic bladder cancer xenografts requires laparotomy and mobilization of the bladder. This procedure inflicts significant morbidity on the mice, is technically challenging and time-consuming. We therefore developed a high-precision, percutaneous approach utilizing ultrasound guidance.

Orthotopic bladder cancer xenografts are the gold standard to study molecular cellular manipulations and new therapeutic agents&#160;in vivo. Suitable ...

In Vivo Optical Imaging of Brain Tumors and Arthritis Using Fluorescent SapC-DOPS Nanovesicles

We describe a multi-angle rotational optical imaging (MAROI) system for in vivo monitoring of physiopathological processes labeled with a fluorescent marker. Mouse models (brain tumor and arthritis) were used to evaluate the usefulness of this method. Saposin C (SapC)-dioleoylphosphatidylserine (DOPS) nanovesicles tagged with CellVue Maroon (CVM) fluorophore were administered intravenously. Animals were then placed in the rotational holder (MARS) of the in vivo imaging system. Images were acquired in 10&#176; steps over 380&#176;. A rectangular&#160;region of interest (ROI) was placed across the full image width at the model disease site. Within the ROI, and for every image, mean fluorescence intensity was computed after background subtraction. In the mouse models studied, the labeled nanovesicles were taken up in both the orthotopic and transgenic brain tumors, and in the arthritic sites (toes and ankles). Curve analysis of the multi angle image ROIs determined the angle with the highest signal. Thus, the optimal angle for imaging each disease site was characterized. The MAROI method applied to imaging of fluorescent compounds is a noninvasive, economical, and precise tool for in vivo quantitative analysis of the disease states in the described mouse models.

In Vivo Optical Imaging of Brain Tumors and Arthritis Using Fluorescent SapC-DOPS Nanovesicles

We describe a multi-angle rotational optical imaging (MAROI) system for in vivo quantitation of a fluorescent marker delivered by saposin C (SapC)-dioleoylphosphatidylserine (DOPS) nanovesicles. Employing mouse models of cancer and arthritis, we demonstrate how the MAROI signal curve analysis can be used for the precise mapping and biological characterization of disease processes.

We describe a multi-angle rotational optical imaging (MAROI) system for in vivo monitoring of physiopathological processes labeled with a fluorescent ...

Fast and Accurate Exhaled Breath Ammonia Measurement

This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. 
Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. 
The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations.

Ammonia is an important physiologic metabolite relevant to various disease and wellness states. It is also a difficult molecule to measure in breath, which demands particular precautions be taken to obtain accurate results. Not all factors influencing ammonia are known, but progress can be difficult without accounting for these factors.

This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that ...

Depletion of Mouse Cells from Human Tumor Xenografts Significantly Improves Downstream Analysis of Target Cells

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic patient tumors in different assays1. Human tumor xenografts represent the gold standard with respect to tumor biology, drug discovery, and metastasis research 2-4. Tumor xenografts can be derived from different types of material like tumor cell lines, tumor tissue from primary patient tumors4 or serially transplanted tumors. When propagated in vivo, xenografted tissue is infiltrated and vascularized by cells of mouse origin. Multiple factors such as the tumor entity, the origin of xenografted material, growth rate and region of transplantation influence the composition and the amount of mouse cells present in tumor xenografts. However, even when these factors are kept constant, the degree of mouse cell contamination is highly variable.
Contaminating mouse cells significantly impair downstream analyses of human tumor xenografts. As mouse fibroblasts show high plating efficacies and proliferation rates, they tend to overgrow cultures of human tumor cells, especially slowly proliferating subpopulations. Mouse cell derived DNA, mRNA, and protein components can bias downstream gene expression analysis, next-generation sequencing, as well as proteome analysis 5. To overcome these limitations, we have developed a fast and easy method to isolate untouched human tumor cells from xenografted tumor tissue. This procedure is based on the comprehensive depletion of cells of mouse origin by combining automated tissue dissociation with the benchtop tissue dissociator and magnetic cell sorting. Here, we demonstrate that human target cells can be can be obtained with purities higher than 96% within less than 20 min independent of the tumor type.

Human tumor xenografts are vascularized and infiltrated by cells of mouse origin during the growth phase in vivo. To circumvent the bias caused by these contaminating cells during downstream analysis, we developed a method allowing for comprehensive depletion of all mouse cells by magnetic cell sorting.

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic ...