The authors have no acknowledgements.

The protocol follows the guidelines of the University Hospital Zurich Human Research Ethics Committee.
1. Diagnoses of Neuromata and Patient Selection
<ol>
	<li>Perform preoperative nerve blocks proximal to the neuroma in order to confirm the diagnoses. Assess the blocks in the middle third of the forearm and exclude potential triggers of the overlapping innervation areas of the SBRN, such as the lateral antebrachial cutaneous nerve (LACN), posterior interosseous nerve (PIN), and a dorsal branch of ulnar nerve10.</li>
	<li>Perform surgery only in patients with considerable pain reduction (at least 5 points on the Visual Analog Scale (VAS) for pain)11.</li>
</ol>
2. Surgical Preparation
<ol>
	<li>Forbid the patient any food or liquid intake 6 h prior to the surgery.</li>
	<li>Place the patient in the middle of the surgical suite on a universal operative table in a beach chair position.</li>
	<li>Place the affected arm/hand on an arm rest.</li>
	<li>Ask the anesthetists to perform endotracheal anesthesia (fentanyl 2 &#181;g/kg, rocuronium 0.6 mg/kg, propofol 150 - 250 mg).</li>
	<li>Disinfect the skin with povidone iodine in the area of liposuction (e.g. inner thigh and/or upper/lower abdomen) and the site of neuroma excision.</li>
	<li>Cover the patient with sterile surgical drapes, leaving exposed the site of liposuction and the surgical site.</li>
</ol>
3. Tumescent Liposuction
<ol>
	<li>Make several small stab (puncture) incisions of approximately 3 - 5 mm diameter with a #11-blade scalpel in the area of liposuction. Incise as far as the subcutaneous layer is reached.</li>
	<li>Inject the tumescent solution containing a dilute lidocaine and epinephrine (500 mL Ringer&#39;s lactate solution, 20 mL of 1% lidocaine, and 1 mg epinephrine) via the 14-gauge infiltrator (infiltrating cannula) into the subcutaneous fat layer (3 mm in depth) in the region of fat harvesting.</li>
	<li>Wait for at least 20 min allowing the tumescent solution to take effect.</li>
	<li>Hook the 3 mm-collecting cannula (outer diameter 3 mm, length 26 cm) to a 60-mL Toomey syringe and start harvesting adipose via the stab incisions. 
	NOTE: The nondominant hand continually controls placement and course of the cannula.</li>
	<li>Pull back the plunger of the Toomey syringe to the 60-mL mark and place a mosquito clamp along the withdrawn plunger in order to maintain negative pressure in the syringe and avoid a continuous vacuum creation by the dominant hand.</li>
	<li>Harvest a minimum of 220 mL of adipose tissue by positioning the Toomey syringes in a vertical position in the provided Toomey syringe stand; this allows the sedimentation of the fat and separation from the fluid.</li>
	<li>Take special care to obtain a good quality fat graft without substantial amount of blood. 
	NOTE: Change the region of liposuction when augmented blood content is noticed.</li>
	<li>Suture the stab incisions with simple stitches and apply pressure as required (e.g. compressive belt).</li>
	<li>Transfer the lipoaspirate into a single-use sterile disposable set of the isolation system.</li>
	<li>Keep one Toomey syringe with lipoaspirate in the provided stand in order to obtain the fat fraction for later lipofilling.</li>
</ol>
4. Adipose Tissue Processing
<ol>
	<li>Close the sterile consumable set. 
	NOTE: The isolation system (see Table of Materials) confirms the completeness by performing a wet test.</li>
	<li>Follow the instructions on the display. 
	NOTE: The process is mostly software controlled and only requires the manual confirmation for the listed steps below by pressing the buttons &#34;next&#34; or &#34;back&#34; on the control panel. The lipoaspirate is transferred into the tissue collection canister. In the tissue collection canister, the lipoaspirate is weighed and automatically cleaned with Ringer&#39;s lactate solution in order to remove the residual blood cells and wetting solution.</li>
	<li>Add more fat if required. 
	NOTE: Depending on the weight of harvested adipose tissue the isolation system asks the user to add more fat or it calculates the amount of additional enzyme reagent to add.</li>
	<li>Add the required amount of enzyme reagent when prompted by the isolation system. 
	NOTE: During the process of enzymatic digestion, separation of lipid and the SVF is achieved. Thereby, the tissue is in oscillating motion. After the enzymatic digestion is completed, the SVF is automatically transferred into the centrifuge chamber for cell concentration. In the centrifuge chamber, the SVF is concentrated to a cell pellet (centrifuge speed is approximately 3,000 x g) . Finally, the cell pellet undergoes a series of washes with Ringer&#39;s lactate solution to reduce residual enzyme levels in the output. When the process is completed, 5 mL of clear fluid (SVF) is obtained.</li>
</ol>
5. Surgical Procedure
<ol>
	<li>To approach the neuroma, make a skin incision over the previously diagnosed neuroma site in the distal third of the forearm.</li>
	<li>Under the usage of surgical binocular loupes magnifier glasses (2.5 - 3.5X), continue to dissect the subcutaneous tissue and identify the involved nerve proximal to the neuroma.
	<ol>
		<li>Subsequently, follow the nerve distally and identify the neuroma (based on visual inspection).</li>
	</ol>
	</li>
	<li>Once the full extension of the neuroma is clear, begin to excise the neuroma by a straight trans-neural scissor cut. If no neuroma is identified, only neurolysis of the nerve is performed.</li>
	<li>Continue with the neurolysis of the remaining nerve stump until 3 cm proximal to the wrist. 
	NOTE: The end of the nerve stump should be located in the middle of the principal incision.</li>
	<li>Arrange two to four small puncture (stab) incisions (1 mm in diameter) with a scalpel through epidermal and dermal cutis around the principal approach.</li>
	<li>Place two to four blunt cannulas (16-gauge, length 9 cm) via the stab incisions perineural to the stump. 
	NOTE: The tip of the cannulas should be directed towards the nerve stump.</li>
	<li>Secure the cannulas in place by adhesive dressing.</li>
	<li>Place the stitches around the cannulas and leave the suture material in situ without securing the node.</li>
	<li>Suture the main incision tightly in order to prevent the outflow of grafting. 
	NOTE: Ensure that cannulas remain in situ.</li>
</ol>
6. Application of the SVF-enriched Fat Graft
NOTE: After approximately 1.5 h of processing, the 5 mL of the processed SVF is ready for further use.
<ol>
	<li>Aspirate 5 mL of SVF in a 10-mL communicating syringe.</li>
	<li>In the same manner, aspirate 2 mL of the sedimented lipid fraction in the opposing 10-mL syringe.</li>
	<li>Mix the 5 mL of SVF with the 2 mL of the sedimented lipid fraction by alternating pulling back the plunger of one syringe and pulling down the plunger of the communicating, opposing syringe until sufficient mixing is obtained.</li>
	<li>Divide the SVF-enriched fat graft equally in two to four 10 mL syringes.</li>
	<li>Distribute the prepared SVF-enriched fat graft one after the other equally around the nerve stump by connecting the syringes to the blunt cannulas. 
	NOTE: Before applying the graft, ensure that the cannulas are secured in the correct position and be careful not to dislocate the cannulas while applying the fat graft.</li>
	<li>Remove the cannulas carefully.</li>
	<li>Then, tape the small puncture incisions with steri-strips.</li>
	<li>Immobilize the hand by applying a splint in the intrinsic plus position (metacarpophalangeal (MCP) joints flexed at 60 -&#160;70&#176;, the interphalangeal (IP) joints fully extended, thumb in the fist projection, wrist in dorsal flexion of 25&#176;).&#160;If only neurolysis of the nerve is performed, no splint is needed and arm and wrist are bandaged for 10 days.</li>
</ol>
7. Postoperative Patient Handling
<ol>
	<li>Transfer the patient to the post-anesthesia recovery unit post-surgery, and allow for sufficient monitoring in the ward.</li>
	<li>Continue to immobilize the wrist for 10 days after the surgery.</li>
	<li>Perform the first change of bandages after 48 h post-surgery and continue at regular intervals (i.e. every second day until discharge).</li>
	<li>Remove the sutures 12 - 14 days postoperatively.</li>
	<li>Perform clinical assessment of pain during follow-up at 2, 6, 12, and 36 months.</li>
</ol>

<ol>
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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intraosseous+nerve+transposition+for+treatment+of+painful+neuromas.">Intraosseous nerve transposition for treatment of painful neuromas.</a> J Hand Surg Am. 10 (2), 270-274 (1985).</li><li>Koch, H., Haas, F., Hubmer, M., Rappl, T., Scharnagl, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Treatment+of+painful+neuroma+by+resection+and+nerve+stump+transplantation+into+a+vein.">Treatment of painful neuroma by resection and nerve stump transplantation into a vein.</a> Ann Plast Surg. 51 (1), 45-50 (2003).</li><li>Vaienti, L., Merle, M., Battiston, B., Villani, F., Gazzola, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perineural+fat+grafting+in+the+treatment+of+painful+end-neuromas+of+the+upper+limb:+a+pilot+study.">Perineural fat grafting in the treatment of painful end-neuromas of the upper limb: a pilot study.</a> J Hand Surg Eur. 38 (1), 36-42 (2013).</li><li>Zuk, P. 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=Multilineage+cells+from+human+adipose+tissue:+implications+for+cell-based+therapies.">Multilineage cells from human adipose tissue: implications for cell-based therapies.</a> Tissue Eng. 7 (2), 211-228 (2001).</li><li>Fraser, J. 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C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interposition+of+a+pedicle+fat+flap+significantly+improves+specificity+of+reinnervation+and+motor+recovery+after+repair+of+transected+nerves+in+adjacency+in+rats.">Interposition of a pedicle fat flap significantly improves specificity of reinnervation and motor recovery after repair of transected nerves in adjacency in rats.</a> Plast Reconstr Surg. 107 (1), 116-123 (2001).</li><li>Calcagni, 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=The+novel+treatment+of+SVF-enriched+fat+grafting+for+painful+end-neuromas+of+superficial+radial+nerve.">The novel treatment of SVF-enriched fat grafting for painful end-neuromas of superficial radial nerve.</a> Microsurgery. , (2016).</li><li>Hawker, G. 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The authors have nothing to disclose.

The purpose of the present study is to methodically illustrate the technical aspects of SVF-enriched fat grafting as a novel treatment for symptomatic end-neuromata.
Neuromata of the SBRN are associated with a surgical success rate of only 33%12. Vaienti et al. presented a series of favorable results in early follow-up using perineural fat grafting (PFG) without adding the SVF in 8 patients with painful neuromata of the upper limb<sup c...

The management of symptomatic end-neuromata of the SBRN remains challenging with a multitude of existing surgical treatments. Principally, the neuroma is excised and the remaining nerve stump is relocated into neighboring structures such as muscles1,2, bone3, or veins4. This is assumed to prevent the out-sprouting of the regenerating neural fascicles by mimicking the ambience of an end-organ. However, none of these techniques proved superior, as high rates of pain relapse and insufficient pain reduction were often observed.
Recently, fat grafting around the remaining nerve stump yielded promising results and was advocated as a new treatment option for painful end-neuromata of the upper limb5. Besides acting as a mechanical barrier to prevent continuing motion and tap pain, the beneficial aspect of fat grafting is rather attributed to the cellular level. Human adipose tissue contains multiple cell types, including preadipocytes, mast cells, pericytes, endothelial cells, vascular smooth muscle cells, fibroblasts, and adipose derived stem cells (ADSCs) along with hematopoietic stem cells6. This heterogeneous cell population is referred to as Adipose-Derived Regeneration Cells (ADRCs) or SVF, and can be obtained from the lipoaspirate by an isolation system (see the Table Of Materials) and applied enzyme reagent (see Table of Materials)7. The exact mechanism of action is still not fully understood; however, SVF has been associated with improvements in angiogenesis, immunomodulation, differentiation, and secretion of extracellular matrix8.
The concentrated cell population of the SVF is added to the fat graft with the purpose to reduce the resorption rate and to increase the regenerative potential of the fat graft, as recent studies revealed pain relapse after 12 months with fat grafting without added SVF5. Moreover, the biological action also provides beneficial effects on the nerve itself by reducing disorganized axonal sprouting of the stump9 and subsequent scar adherences which might result in nerve entrapment.
The first clinical study to describe SVF-enriched fat grafting as a novel surgical option for the treatment of symptomatic end-neuromata of SBRN has been recently published10. In general, the technique can be applied to any neuroma occurring after accidental or iatrogenic nerve injury. The aim of the present subsequent study is to methodically illustrate the technical aspects of this procedure.

<table border="0" cellpadding="0" cellspacing="0" width="688">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">Cytori Celution System</td>
			<td style="width:71px;">Cytori</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">isolation system</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Celase</td>
			<td style="width:71px;">Cytori</td>
			<td style="width:119px;"></td>
			<td>enyzme reagent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">liposuction system</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:331px;">tumescent solution (500 ml Lactated Ringers, 20 ml of 1% lidocaine and 1 mg epinephrine)</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">14-gauge infiltrator</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">3 mm-collecting cannula (15, 26, 32 cm)</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">60 mL Tommey syringes</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">mosquito clamp</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Toomey syringe stand</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:331px;">4 cannulas (fat injecting cannulas 1.5 mm, syringe NO.2, 90 mm)</td>
			<td style="width:71px;">Chalybs</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">10 mL syringes</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">connecting device for syringes</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">#11- and #15-blade scalpel</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">stevens scissors</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">pins pincette</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">bipolar electrocautery</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:331px;">suture material</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">adhesive dressing</td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">binocular loupes magnifier glasses (2.5-3.5x)</td>
			<td style="width:71px;">Carl Zeiss</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:331px;">Statistical Package for Social Sciences, version 22</td>
			<td>IBM</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

stromal vascular fraction-enriched fat grafting for the treatment of symptomatic end-neuromata

The purpose of this study was to methodically illustrate and highlight the crucial steps of stromal vascular fraction (SVF)-enriched fat grafting as a novel treatment of symptomatic end-neuromata of peripheral sensory nerves, and in this study, specifically of the superficial branch of the radial nerve (SBRN). Despite a multitude of existing treatments, persistent postoperative pain and common pain relapse are still very common, independent of the procedure assessed. The neuroma is microsurgically excised accordingly to standardized protocol. Instead of the relocation of the regenerating nerve stump in neighboring anatomical structures, such as muscle or bone, a fat graft is applied perifocally and acts as a mechanical barrier. In order to reduce the fat resorption rate and boost the regenerative potential of the graft, the highly concentrated SVF is integrated in the grafting. The SVF is isolated from subcutaneous fat by enzymatic and mechanic separation of the lipoaspirate by a specific commercial isolation system. The SVF-enriched fat graft provides both a mechanical barrier and various biological effects at the cellular level, including improving angiogenesis, inflammation, and fibrosis. Both mechanical and biologic effects help to reduce the disorganized axonal outgrowth of the nerve stump during nerve regeneration and hence prevent the recurrence of painful end-neuromata.

Data were analyzed using statistical software and presented as means &#177; standard deviations. The Kolmogorov-Smirnov test was applied to verify the nonparametric distribution of the study population and confirmed a negative empirical distribution. Based on the nonparametric nature of the study population, the Wilcoxon&#39;s test for related samples was employed to compare preoperative and postoperative outcomes. Statistical significance was regarded at p-values less than 0.05<s...

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Stromal Vascular Fraction-enriched Fat Grafting for the Treatment of Symptomatic End-neuromata

The purpose of the study is to illustrate the technical procedure of stromal vascular fraction (SVF)-enriched fat grafting as a novel treatment of symptomatic end-neuromata. This technique provides advantages of both the mechanical barrier and the biological action at the cellular level by the processed and concentrated SVF.

The purpose of this study was to methodically illustrate and highlight the crucial steps of stromal vascular fraction (SVF)-enriched fat grafting as a ...

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Medicine

7.6K Views.  University Hospital Zurich. The purpose of the study is to illustrate the technical procedure of stromal vascular fraction (SVF)-enriched fat grafting as a novel treatment of symptomatic end-neuromata. This technique provides advantages of both the mechanical barrier and the biological action at the cellular level by the processed and concentrated SVF.

Video: Stromal Vascular Fraction-enriched Fat Grafting for the Treatment of Symptomatic End-neuromata

Experimental Generation of Carcinoma-Associated Fibroblasts (CAFs) from Human Mammary Fibroblasts

Carcinomas are complex tissues comprised of neoplastic cells and a non-cancerous compartment referred to as the 'stroma'. The stroma consists of extracellular matrix (ECM) and a variety of mesenchymal cells, including fibroblasts, myofibroblasts, endothelial cells, pericytes and leukocytes 1-3.
The tumour-associated stroma is responsive to substantial paracrine signals released by neighbouring carcinoma cells. During the disease process, the stroma often becomes populated by carcinoma-associated fibroblasts (CAFs) including large numbers of myofibroblasts. These cells have previously been extracted from many different types of human carcinomas for their in vitro culture. A subpopulation of CAFs is distinguishable through their up-regulation of &alpha;-smooth muscle actin (&alpha;-SMA) expression4,5. These cells are a hallmark of 'activated fibroblasts' that share similar properties with myofibroblasts commonly observed in injured and fibrotic tissues 6. The presence of this myofibroblastic CAF subset is highly related to high-grade malignancies and associated with poor prognoses in patients.
Many laboratories, including our own, have shown that CAFs, when injected with carcinoma cells into immunodeficient mice, are capable of substantially promoting tumourigenesis 7-10. CAFs prepared from carcinoma patients, however, frequently undergo senescence during propagation in culture limiting the extensiveness of their use throughout ongoing experimentation. To overcome this difficulty, we developed a novel technique to experimentally generate immortalised human mammary CAF cell lines (exp-CAFs) from human mammary fibroblasts, using a coimplantation breast tumour xenograft model.
In order to generate exp-CAFs, parental human mammary fibroblasts, obtained from the reduction mammoplasty tissue, were first immortalised with hTERT, the catalytic subunit of the telomerase holoenzyme, and engineered to express GFP and a puromycin resistance gene. These cells were coimplanted with MCF-7 human breast carcinoma cells expressing an activated ras oncogene (MCF-7-ras cells) into a mouse xenograft. After a period of incubation in vivo, the initially injected human mammary fibroblasts were extracted from the tumour xenografts on the basis of their puromycin resistance 11.
We observed that the resident human mammary fibroblasts have differentiated, adopting a myofibroblastic phenotype and acquired tumour-promoting properties during the course of tumour progression. Importantly, these cells, defined as exp-CAFs, closely mimic the tumour-promoting myofibroblastic phenotype of CAFs isolated from breast carcinomas dissected from patients. Our tumour xenograft-derived exp-CAFs therefore provide an effective model to study the biology of CAFs in human breast carcinomas. The described protocol may also be extended for generating and characterising various CAF populations derived from other types of human carcinomas.

Experimental Generation of Carcinoma-Associated Fibroblasts CAFs from Human Mammary Fibroblasts

Carcinoma-associated fibroblasts (CAFs) rich in myofibroblasts present within the tumour stroma, play a major role in driving tumour progression. We developed a coimplantation tumour xengraft model for experimentally generating CAFs from human mammary fibroblasts. The protocol describes how to establish CAF myofibroblasts that acquire an ability to promote tumourigenesis.

Carcinomas are complex tissues comprised of neoplastic cells and a non-cancerous compartment referred to as the 'stroma'. The stroma consists of ...

Orthotopic Aortic Transplantation in Mice for the Study of Vascular Disease

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. This is largely true, but there are a number of important principles that can reduce the difficulty of these procedures and enhance reproducibility. Orthotopic aortic transplantation is an excellent procedure in which to learn these principles because it involves only two end-to-end anastomoses, but requires good suturing technique and handling of the vessels for consistent success. This procedure begins with the procurement of a length of abdominal aorta from a donor animal, followed by division of the native aorta in the recipient. The procured aorta is then placed between the divided ends of the recipient aorta and sutured into place using end-to-end anastomoses. To accomplish this objective successfully requires a high degree of concentration, good tools, a steady hand, and an appreciation of how easily the vasculature of a mouse can be damaged, resulting in thrombosis. Learning these important principles is what occupies most of the beginner's time when learning microsurgery in small rodents. Throughout this protocol, we refer to these important points. This model can be used to study vascular disease in a variety of different experimental systems1-8. In the context shown here, it is most often used for the study of post-transplant vascular disease, a common long-term complication of solid organ transplantation in which intimal hyperplasia occurs within the allograft. The primary advantage of the model is that it facilitates quantitative morphometric analyses and the transplanted vessel lies contiguous to the endogenous vessel, which can serve as an additional control9. The technique shown here is most often used for mice weighing 18-25 grams. We have accumulated most of our experience using the C57BL/6J, BALB/cJ, and C3H/HeJ strains.

We describe a technique in which a section of the abdominal aorta from a mouse is transplanted orthotopically to just below the renal arteries in an allogeneic or syngeneic recipient. This technique can be useful in studies in which transplantation of large arteries of uniform size is deemed advantageous.

Vascular procedures involving anastomoses in the mouse are generally thought to be difficult and highly dependent on the skill of the individual surgeon. ...

Technical Aspects of the Mouse Aortocaval Fistula

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.

The goal is to produce an arteriovenous fistula that is simple and reproducible. This method does not use sutures or glue adhesive. Therefore the samples can be used with the least amount of foreign materials for analysis.

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta ...

Three-dimensional Co-culture Model for Tumor-stromal Interaction

Cancer progression (initiation, growth, invasion and metastasis) occurs through interactions between malignant cells and the surrounding tumor stromal cells. The tumor microenvironment is comprised of a variety of cell types, such as fibroblasts, immune cells, vascular endothelial cells, pericytes and bone-marrow-derived cells, embedded in the extracellular matrix (ECM). Cancer-associated fibroblasts (CAFs) have a pro-tumorigenic role through the secretion of soluble factors, angiogenesis and ECM remodeling. The experimental models for cancer cell survival, proliferation, migration, and invasion have mostly relied on two-dimensional monocellular and monolayer tissue cultures or Boyden chamber assays. However, these experiments do not precisely reflect the physiological or pathological conditions in a diseased organ. To gain a better understanding of tumor stromal or tumor matrix interactions, multicellular and three-dimensional cultures provide more powerful tools for investigating intercellular communication and ECM-dependent modulation of cancer cell behavior. As a platform for this type of study, we present an experimental model in which cancer cells are cultured on collagen gels embedded with primary cultures of CAFs.

Here we present a protocol to co-culture in three-dimensions, which is useful for investigating multicellular interactions and extracellular matrix-dependent modulation of cancer cell behavior. In this experimental model, cancer cells are cultured on collagen gels embedded with human cancer-associated fibroblasts.

Cancer progression (initiation, growth, invasion and metastasis) occurs through interactions between malignant cells and the surrounding tumor stromal ...

Transplantation Into the Mouse Ovarian Fat Pad

Orthotopic transplantation assays in mice are invaluable for studies of cell regeneration and neoplastic transformation. Common approaches for orthotopic transplantation of ovarian surface and tubal epithelia include intraperitoneal and intrabursal administration of cells. The respective limitations of these methods include poorly defined location of injected cells and limited space volume. Furthermore, they are poorly suited for long-term structural preservation of transplanted organs. To address these challenges, we have developed an alternative approach, which is based on the introduction of cells and tissue fragments into the mouse fat pad. The mouse ovarian fat pad is located in the immediate vicinity of the ovary and uterine tube (aka oviduct, fallopian tube), and provides a familiar microenvironment for cells and tissues of these organs. In our approach fluorescence-labeled mouse and human cells, and fragments of the uterine tube are engrafted by using minimally traumatic dorsal incision surgery. Transplanted cells and their outgrowths are easily located in the ovarian fat pad for over 40 days. Long-term transplantation of the entire uterine tube allows correct preservation of all principle tissue components, and does not result in adverse side effects, such as fibrosis and inflammation. Our approach should be uniquely applicable for answering important biological questions such as differentiation, regenerative and neoplastic potential of specific cell populations. Furthermore, it should be suitable for studies of microenvironmental factors in normal development and cancer.

We describe an ovarian fad pad transplantation assay suitable for studies of normal and transformed epithelia of the female reproductive tract. The mouse fat pad allows transplantation of large tissue fragments, is easily accessible for surgery and imaging, and provides the most favorable native environment for tissues of M&#252;llerian origin.

Orthotopic transplantation assays in mice are invaluable for studies of cell regeneration and neoplastic transformation. Common approaches for orthotopic ...

Network Analysis of Foramen Ovale Electrode Recordings in Drug-resistant Temporal Lobe Epilepsy Patients

Approximately 30% of epilepsy patients are refractory to antiepileptic drugs. In these cases, surgery is the only alternative to eliminate/control seizures. However, a significant minority of patients continues to exhibit post-operative seizures, even in those cases in which the suspected source of seizures has been correctly localized and resected. The protocol presented here combines a clinical procedure routinely employed during the pre-operative evaluation of temporal lobe epilepsy (TLE) patients with a novel technique for network analysis. The method allows for the evaluation of the temporal evolution of mesial network parameters. The bilateral insertion of foramen ovale electrodes (FOE) into the ambient cistern simultaneously records electrocortical activity at several mesial areas in the temporal lobe. Furthermore, network methodology applied to the recorded time series tracks the temporal evolution of the mesial networks both interictally and during the seizures. In this way, the presented protocol offers a unique way to visualize and quantify measures that considers the relationships between several mesial areas instead of a single area.

This protocol describes a procedure to track the evolution of mesial network measures in temporal lobe epilepsy (TLE) patients. It is based on the combination of intracranial recordings with a novel numerical technique for data analysis. Specifically, we present a protocol for network analyses of foramen ovale recordings.

Approximately 30% of epilepsy patients are refractory to antiepileptic drugs. In these cases, surgery is the only alternative to eliminate/control ...

Trans-Tympanic Drug Delivery for the Treatment of Ototoxicity

The systemic administration of protective agents to treat drug-induced ototoxicity is limited by the possibility that these protective agents could interfere with the chemotherapeutic efficacy of the primary drugs. This is especially true for the drug cisplatin, whose anticancer actions are attenuated by antioxidants which provide adequate protection against hearing loss. Other current or potential otoprotective agents could pose a similar problem, if administered systemically. The application of various biologicals or protective agents directly to the cochlea would allow for high levels of these agents locally with limited systemic side effects. In this report, we demonstrate a trans-tympanic method of delivery of various drugs or biological reagents to the cochlea, which should enhance basic science research on the cochlea and provide a simple way of directing the use of otoprotective agents in the clinics. This report details a method of trans-tympanic drug delivery and provides examples of how this technique has been used successfully in experimental animals to treat cisplatin ototoxicity.

We present a technique for localized administration of drugs through the trans-tympanic route into the cochlea. Drug delivery through this route would not interfere with the anti-cancer efficacy of the chemotherapeutic drugs such as cisplatin.

The systemic administration of protective agents to treat drug-induced ototoxicity is limited by the possibility that these protective agents could ...

Clinical Protocol of Producing Adipose Tissue-Derived Stromal Vascular Fraction for Potential Cartilage Regeneration

Osteoarthritis (OA) is one of the most common debilitating disorders.&#160;Recently, numerous attempts have been made to improve the functions of the knees by using different forms of mesenchymal stem cells (MSCs). In Korea, bone marrow concentrates and cord blood-derived stem cells have been approved by the Korean Food and Drug Administration (KFDA) for cartilage regeneration. In addition, an adipose tissue-derived stromal vascular fraction (SVF) has been allowed by the KFDA for joint injections in human patients. Autologous adipose tissue-derived SVF contains extracellular matrix (ECM) in addition to mesenchymal stem cells. ECM excretes various cytokines that, along with hyaluronic acid (HA) and platelet-rich plasma (PRP) activated by calcium chloride, may help MSCs to regenerate cartilage and improve knee functions. In this article, we presented a protocol to improve knee functions by regenerating cartilage-like tissue in human patients with OA. The result of the protocol was first reported in 2011 followed by a few additional publications. The protocol involves liposuction to obtain autologous lipoaspirates that are mixed with collagenase. This lipoaspirates-collagenase mixture is then cut and homogenized to remove large fibrous tissue that may clog up the needle during the injection. Afterwards, the mixture is incubated to obtain adipose tissue-derived SVF. The resulting adipose tissue-derived SVF, containing both adipose tissue-derived MSCs and remnants of ECM, is injected into knees of patients, combined with HA and calcium chloride activated PRP. Included are three cases of patients who were treated with our protocol resulting in improvement of knee pain, swelling, and range of motion along with MRI evidence of hyaline cartilage-like tissue.

Here, we present a protocol to produce an adipose tissue-derived stromal vascular fraction and its application to improve knee functions by regenerating cartilage-like tissue in human patients with osteoarthritis.

Osteoarthritis (OA) is one of the most common debilitating disorders.&#160;Recently, numerous attempts have been made to improve the functions of the ...

Isolation of Adipose Derived Regenerative Cells for the Treatment of Erectile Dysfunction Following Radical Prostatectomy

Stem cells are used in many research areas within regenerative medicine in part because these treatments can be curative rather than symptomatic. Stem cells can be obtained from different tissues and several methods for isolation have been described. The presented method for the isolation of adipose-derived regenerative cells (ADRCs) can be used within many therapeutic areas because the method is a general procedure and, therefore, not limited to erectile dysfunction (ED) therapy. ED is a common and serious side effect to radical prostatectomy (RP) since ED often is not well treated with conventional therapy. Using ADRC&#8217;s as treatment for ED has attracted great interest due to the initial positive results after a single injection of cells into the corpora cavernosum. The method used for the isolation of ADRC&#8217;s is a simple, automated process, that is reproducible and ensures a uniform product. Furthermore, the sterility of the isolated product is ensured because the entire process takes place in a closed system. It is important to minimize the risk of contamination and infection since the stem cells are used for injection in humans. The whole procedure can be done within 2.5-3.5 hours and does not require a classified laboratory which eliminates the need for shipping tissue to an off-site. However, the procedure has some limitations since the minimum amount of drained lipoaspirate for the isolation device to function is 100 g.

Precise disclosure of methods and protocols is crucial for large scale uptake of stem cell therapies. Here, we present a protocol to isolate adipose-derived regenerative cells, used for a single intracavernous injection as treatment of erectile dysfunction (ED) following radical prostatectomy (RP).

Stem cells are used in many research areas within regenerative medicine in part because these treatments can be curative rather than symptomatic. Stem ...

Establishing a Swine Model of Post-myocardial Infarction Heart Failure for Stem Cell Treatment

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major causes of mortality and morbidity around the world. Cell-based therapies for cardiac repair and improvement of left ventricular function after MI have attracted considerable attention. Accordingly, the safety and efficacy of these cell transplantations should be tested in a preclinical large animal model of HF prior to clinical use. Pigs are widely used for cardiovascular disease research due to their similarity to humans in terms of heart size and coronary anatomy. Therefore, we sought to present an effective protocol for the establishment of a porcine chronic HF model using closed-chest coronary balloon occlusion of the left circumflex artery (LCX), followed by rapid ventricular pacing induced with pacemaker implantation. Eight weeks later, the stem cells were administered by intramyocardial injection in the peri-infarct area. Then the infarct size, cell survival, and left ventricular function (including echocardiography, hemodynamic parameters, and electrophysiology) were evaluated. This study helps establish a stable preclinical large animal HF model for stem cell treatment.

We sought to establish a swine model of heart failure induced by left circumflex artery blockage and rapid pacing to test the effect and safety of intramyocardial administration of stem cells for cell-based therapies.

Although advances have been achieved in the treatment of heart failure (HF) following myocardial infarction (MI), HF following MI remains one of the major ...