Name: construction and characterization of a novel vocal fold bioreactor
Uploaded: 2014-08-01T13:00:00
Description: Watch this Scientific Journal Video about Construction and Characterization of a Novel Vocal Fold Bioreactor at JoVE.com

We thank Dr. Jeffrey Caplan for his training and advice on confocal imaging. We also thank the Keck Electron Microscopy Lab and Dr. Chaoying Ni for SEM assistance. This work is funded by National Institutes of Health (NIDCD, R01DC008965 and R01DC011377). ABZ acknowledges NSF Integrative Graduate Education &#38; Research Traineeship (IGERT) program for funding.

1. Bioreactor Assembly (Video 1)
<ol>
	<li>Make an aluminum mold (circular die + spacer pin) with pre-determined inner and outer dimensions (Figure&#160;1).</li>
	<li>Using the mold from step 1.1, fabricate a silicone membrane (diameter: 42 mm, thickness: 1.5 mm, Figure&#160;1) with an entrenched sleeve (diameter: 12 mm, thickness ~0.25 mm, shaped by the spacer pin in Figure 1) in the middle using a commercially available silicone elastomer kit.</li>
	<li>Make a pair o...

<ol>
	<li>Titze, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical-Stress+in+Phonation.">Mechanical-Stress in Phonation.</a> J. Voice. 8, 99-105 (1994).</li><li>Titze, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+Relation+Between+Subglottal+Pressure+and+Fundamental-Frequency+in+Phonation.">On the Relation Between Subglottal Pressure and Fundamental-Frequency in Phonation.</a> J. Acoust. Soc. Am. 85, 901-906 (1989).</li><li>Gray, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+physiology+of+the+vocal+folds.">Cellular physiology of the vocal folds.</a> Otolaryngol. Clin. N. Am. 33, 679-698 (2000).</li><li>Thibeault, S. L., Gray, S. D., Bless, D. M., Chan, R. W., Ford, C. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Histologic+and+rheologic+characterization+of+vocal+fold+scarring.">Histologic and rheologic characterization of vocal fold scarring.</a> J. Voice. 16, 96-104 (2002).</li><li>Hansen, J. K., Thibeault, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+understanding+and+review+of+the+literature:+Vocal+fold+scarring.">Current understanding and review of the literature: Vocal fold scarring.</a> J. Voice. 20, 110-120 (2006).</li><li>Pittenger, M. F., 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+potential+of+adult+human+mesenchymal+stem+cells.">Multilineage potential of adult human mesenchymal stem cells.</a> Science. 284, 143-147 (1999).</li><li>Hanson, S. E., 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=Characterization+of+Mesenchymal+Stem+Cells+From+Human+Vocal+Fold+Fibroblasts.">Characterization of Mesenchymal Stem Cells From Human Vocal Fold Fibroblasts.</a> Laryngoscope. 120, 546-551 (2010).</li><li>Tong, Z., Duncan, R. L., Jia, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Modulating+the+behaviors+of+mesenchymal+stem+cells+via+the+combination+of+high-frequency+vibratory+stimulations+and+fibrous+scaffolds.">Modulating the behaviors of mesenchymal stem cells via the combination of high-frequency vibratory stimulations and fibrous scaffolds.</a> Tissue Eng. Part A. 19, 1862-1878 (2013).</li><li>Tong, Z., Sant, S., Khademhosseini, A., Jia, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlling+the+Fibroblastic+Differentiation+of+Mesenchymal+Stem+Cells+Via+the+Combination+of+Fibrous+Scaffolds+and+Connective+Tissue+Growth+Factor.">Controlling the Fibroblastic Differentiation of Mesenchymal Stem Cells Via the Combination of Fibrous Scaffolds and Connective Tissue Growth Factor.</a> Tissue Eng. Part A. 17, 2773-2785 (2011).</li><li>Jones, D. L., Wagers, A. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=No+place+like+home:+anatomy+and+function+of+the+stem+cell+niche.">No place like home: anatomy and function of the stem cell niche.</a> Nat. Rev. Mol. Cell Biol. 9, 11-21 (1038).</li><li>Wang, J. H., Thampatty, B. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanobiology+of+Adult+and+Stem+Cells.">Mechanobiology of Adult and Stem Cells.</a> Int. Rev. of Cell Mol. Biol. 271, 301-346 (2008).</li><li>Doroski, D. M., Levenston, M. E., Temenoff, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclic+tensile+culture+promotes+fibroblastic+differentiation+of+marrow+stromal+cells+encapsulated+in+poly+(ethylene+glycol)-based+hydrogels.">Cyclic tensile culture promotes fibroblastic differentiation of marrow stromal cells encapsulated in poly (ethylene glycol)-based hydrogels.</a> Tissue Eng. Part A. 16, 3457-3466 (2010).</li><li>Kim, B. S., Nikolovski, J., Bonadio, J., Mooney, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclic+mechanical+strain+regulates+the+development+of+engineered+smooth+muscle+tissue.">Cyclic mechanical strain regulates the development of engineered smooth muscle tissue.</a> Nat. Biotechnol. 17, 979-983 (1999).</li><li>Webb, 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=Cyclic+strain+increases+fibroblast+proliferation,+matrix+accumulation,+and+elastic+modulus+of+fibroblast-seeded+polyurethane+constructs.">Cyclic strain increases fibroblast proliferation, matrix accumulation, and elastic modulus of fibroblast-seeded polyurethane constructs.</a> J. Biomech. 39, 1136-1144 (2006).</li><li>Kim, Y. J., Sah, R. L. Y., Grodzinsky, A. J., Plaas, A. H. K., Sandy, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+Regulation+of+Cartilage+Biosynthetic+Behavior+-+Physical+Stimuli..">Mechanical Regulation of Cartilage Biosynthetic Behavior - Physical Stimuli..</a> Arch. Biochem. Biophys. 311, 1-12 (1994).</li><li>Titze, I. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+validation+of+a+bioreactor+for+engineering+vocal+fold+tissues+under+combined+tensile+and+vibrational+stresses.">Design and validation of a bioreactor for engineering vocal fold tissues under combined tensile and vibrational stresses.</a> J. Biomech. 37, 1521-1529 (2004).</li><li>Kutty, J. K., Webb, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vibration+stimulates+vocal+mucosa-like+matrix+expression+by+hydrogel-encapsulated+fibroblasts.">Vibration stimulates vocal mucosa-like matrix expression by hydrogel-encapsulated fibroblasts.</a> J. Tissue Eng. Regen. Med. 4, 62-72 (2010).</li><li>Farran, A. J. E., 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=Design+and+Characterization+of+a+Dynamic+Vibrational+Culture+System.">Design and Characterization of a Dynamic Vibrational Culture System.</a> J. Tissue Eng. Regen. Med. , (2011).</li><li>Reneker, D. H., Yarin, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrospinning+jets+and+polymer+nanofibers.">Electrospinning jets and polymer nanofibers.</a> Polymer. 49, 2387-2425 (2008).</li><li>Wang, Y., Theobald, P., Tyrer, J., Lepper, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+application+of+scanning+vibrometer+in+mapping+ultrasound+fields.">The application of scanning vibrometer in mapping ultrasound fields.</a> J. Phys.: Conf. Ser. 1, 167-173 (2004).</li><li>Brown, W. S., Morris, R. J., Hollien, H., Howell, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Speaking+Fundamental-Frequency+Characteristics+as+a+Function+of+Age+and+Professional.">Speaking Fundamental-Frequency Characteristics as a Function of Age and Professional.</a> J. Voice. 5, 310-315 (1991).</li><li>Ingber, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+mechanotransduction:+putting+all+the+pieces+together+again.">Cellular mechanotransduction: putting all the pieces together again.</a> Faseb J. 20, 811-827 (2006).</li><li>Titze, I. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+validation+of+a+bioreactor+for+engineering+vocal+fold+tissues+under+combined+tensile+and+vibrational+stresses.">Design and validation of a bioreactor for engineering vocal fold tissues under combined tensile and vibrational stresses.</a> J. Biomech. 37, 1521-1529 (2004).</li><li>Moore, J., Thibeault, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Insights+Into+the+Role+of+Elastin+in+Vocal+Fold+Health+and+Disease.">Insights Into the Role of Elastin in Vocal Fold Health and Disease.</a> J. Voice. 26, 269-275 (2012).</li><li>Thibeault, S. L., Bless, D. M., Gray, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interstitial+protein+alterations+in+rabbit+vocal+fold+with+scar.">Interstitial protein alterations in rabbit vocal fold with scar.</a> J. Voice. 17, 377-383 (2003).</li><li>Branski, R. C., Verdolini, K., Sandulache, V., Rosen, C. A., Hebda, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vocal+fold+wound+healing:+A+review+for+clinicians.">Vocal fold wound healing: A review for clinicians.</a> J. Voice. 20, 432-442 (2006).</li><li>Clark, I. A., Swingler, T. E., Sampieri, C. L., Edwards, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+regulation+of+matrix+metalloproteinases+and+their+inhibitors.">The regulation of matrix metalloproteinases and their inhibitors.</a> Int. J. Biochem. Cell B. 40, 1362-1378 (2008).</li><li>Silver, F. H., Horvath, I., Foran, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Viscoelasticity+of+the+vessel+wall:+The+role+of+collagen+and+elastic+fibers.">Viscoelasticity of the vessel wall: The role of collagen and elastic fibers.</a> Crit. Rev. Biomed. Eng. 29, 279-301 (2001).</li><li>Kutty, J. K., Webb, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue+Engineering+Therapies+for+the+Vocal+Fold+Lamina+Propria.">Tissue Engineering Therapies for the Vocal Fold Lamina Propria.</a> Tissue Eng. Part B: Rev. 15, 249-262 (2009).</li></ol>

Successful engineering of functional vocal fold tissues in vitro requires the recreation of a vocal fold-like microenvironment to mediate the behaviors of multipotent cells. It is generally accepted that tissue or organ structures reflect the functions they are required to perform.22 For vocal fold tissues, the high frequency vibrations that occur during phonation are proposed to be important for tissue maturation. In our study, PCL scaffolds are used to provide a ligament-like structural support whil...

The human vocal fold, composed of an epithelial layer, the lamina propria (LP) and the vocalis muscle, is a specialized soft tissue that converts air flow from the lungs into acoustic waves for sound production.1 Vocal folds oscillate regularly during normal phonation, exhibiting strains of up to 30% at fundamental frequencies ranging from 100-300 Hz.2 Adult vocal fold LP is a gradient structure composed of a superficial (SLP), an intermediate (ILP) and a deep (DLP) layer. Further classification groups the epithelium and the SLP as the mucosa layer, and combines the ILP and DLP into the vocal ligament.3 The SLP layer contains primarily an amorphous matrix with sparsely dispersed collagenous fibers, while the ligament is enriched with mature collagen and elastin fibers to provide sufficient strength.4 The structure and mechanics of newborn vocal folds vary significantly from their mature counterparts. Although mechanisms regulating vocal fold development and maturation are not yet fully understood, experimental evidence has pointed to the defining roles of vocalization-derived mechanical stress.
Several medical conditions, including voice abuse, infections, chemical irritants and surgical procedures, can damage the vocal fold. Vocal fold disorders affect an estimated 3-9% of the U.S. population. Current treatment methods for vocal fold disorders are limited5 and a stem cell-based tissue engineering approach has emerged as a promising strategy for restoring vocal fold function. Mesenchymal stem cells (MSCs) are a suitable alternative to the primary vocal fold fibroblasts for vocal fold tissue engineering.6-9 Stem cell fate specification and subsequent tissue development are mediated by the specific niche they reside in, of which the mechanical condition is a vital factor.10 Mechanical forces are essential regulators of tissue morphogenesis and homeostasis, especially for tissues that are routinely subjected to loading.11 From a tissue engineering perspective, it has been demonstrated that exposure to physiologically relevant mechanical stimulations promotes stem cell differentiation and tissue-specific matrix remodeling.12-15
Tissue culture bioreactors are designed to simulate the desired physiological environment for cell or tissue growth in vitro. For vocal fold tissue engineering, it is especially critical to recreate the mechanical environment of the phonating vocal folds. An ideal vocal fold bioreactor should effectively deliver vibratory cues to culture cells, allowing facile control over frequency, amplitude and duration of vibrations. Titze and coworkers devised a vocal fold bioreactor (T1 bioreactor)16 that combines static stretch with high frequency (20-200 Hz) oscillations to stimulate the cellular production of matrix proteins. Using this bioreactor, Webb and colleagues17 studied the effects of 10-day, 100-Hz vibrations on dermal fibroblasts cultured in a hyaluronic acid (HA)-based hydrogel. Constructs subjected to vibration exhibited an elevated expression of HA synthase-2 (HAS2), decorin, fibromodulin and matrix metalloproteinase-1 (MMP1), relative to the static controls. The stimulatory effects were found to be time dependent. More recently, our group18 assembled a vocal fold bioreactor (J1 bioreactor) using a power amplifier, a function generator, an enclosed loud speaker and a circumferentially-anchored silicone membrane that transfers the oscillating air to the attached cells. Neonatal foreskin fibroblasts cultivated in the J1 bioreactor were subjected to 1 hr of vibration at 60, 110 or 300 Hz, with an in-plane strain of up to 0.05%. The qPCR results suggested that the expression of some ECM genes was moderately altered in response to the varied vibratory frequencies and amplitudes.
These bioreactor designs, while intriguing, have several limitations. For example, the T1 system requires a large number of connectors and bars for mechanical coupling, limiting the maximum frequencies attainable. Moreover, cells may be subjected to undesirable mechanical agitation and fluid perturbation that complicate the data interpretation. The J1 bioreactor, on the other hand, exhibits relatively low energy conversion efficiency and is not user-friendly. In addition, vibration frequently detaches the cell-laden constructs from the underlying silicone membrane. The J2 vocal fold bioreactor reported here, designed based on the same principle as the J1 version, is optimized for consistency and reproducibility. The phonation-mimicking vibrations are generated aerodynamically in individually fitted vibration chambers where MSC-populated fibrous poly(&#949;-caprolactone) (PCL) scaffolds are effectively secured. Laser Doppler Vibrometry (LDV) allows the user to verify the vibratory profile of the membrane/scaffold assembly. In our demonstration, MSCs are exposed to 200-Hz sinusoidal vibrations with a 1-hr-on-1-hr-off (OF) pattern for a total of 12 hr daily for 7 days. Cellular responses to the imposed vibratory cues are investigated systematically. Overall, the J2 vocal fold provides the most user-friendly features, allowing dynamic cell culture studies to be conducted in a high throughput and reproducible fashion.

<table border="0" cellpadding="0" cellspacing="0" width="853">
	<tbody>
		<tr height="16">
			<td height="16" style="height:17px;width:248px;">silicone elastomer kit</td>
			<td style="width:188px;">Dow Corning</td>
			<td style="width:124px;">Sylgard 184</td>
			<td style="width:293px;">cure the membrane at 100 C for 2 hr</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">PCL</td>
			<td>Sigma Aldrich</td>
			<td>440744-500G</td>
			<td>Mn ~ 80 kDa, dissolve overnight</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">chloroform</td>
			<td>Sigma Aldrich</td>
			<td>C7559-5VL</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">human bone marrow-derived MSCs</td>
			<td>Lonza</td>
			<td>PT-2501</td>
			<td>received with passage 2</td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">MSC maintenance media</td>
			<td>Lonza</td>
			<td>PT-3001</td>
			<td style="width:293px;">10% FBS in basal media supplemented 
			with L-glutamine, gentamicin and amphotericin</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Accutase cell dissociation reagent</td>
			<td>Life Technologies</td>
			<td>A11105-01</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">ethanol</td>
			<td>Sigma Aldrich</td>
			<td>E7023-500ML</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">fibronectin</td>
			<td>Sigma Aldrich</td>
			<td>F2006-1MG</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">MMP1 DuoSet ELISA kit</td>
			<td>R&#38;D systems</td>
			<td>DY901</td>
			<td></td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">HA ELISA kit</td>
			<td>Echelon Biosciences</td>
			<td>&#160;K-1200&#160;&#160;</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">PBS</td>
			<td>Life Technologies</td>
			<td>14190-136</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">propidium iodide&#160;</td>
			<td>Life Technologies</td>
			<td>P1304MP</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Syto-13&#160;</td>
			<td>Life Technologies</td>
			<td>S7575</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">QuantiTect reverse transcription kit&#160;</td>
			<td>Qiagen</td>
			<td>205311</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">SYBR Green PCR master mix</td>
			<td>Life Technologies</td>
			<td>4309155</td>
			<td></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">replacement speaker</td>
			<td style="width:188px;">DAYTON audio 
			(via Parts Express)</td>
			<td>DS90-8</td>
			<td>paper cone, full range (80-13000 Hz), 85dB</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Ergo Micro torque screwdriver</td>
			<td>Mountz</td>
			<td># 020377</td>
			<td>torque range: 20-120 cN.m</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">stereo speaker selector</td>
			<td>RadioShack</td>
			<td>40-244</td>
			<td>maximum power handling 50 W</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">function generator&#160;</td>
			<td>Agilent&#160;</td>
			<td>33220A</td>
			<td>frequency range 1 &#181;Hz- 20 MHz</td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">power amplifier&#160;</td>
			<td>PYLE audio</td>
			<td>PylePro PT2400</td>
			<td style="width:293px;">frequency response: 10 Hz-50 kHz, two speaker 
			channels</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">cell culture incubator&#160;</td>
			<td>Thermo Fisher&#160;</td>
			<td>Steri-Cult 3307</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">syringe pump&#160;</td>
			<td>New Era Pump Systems</td>
			<td>NE-300</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">High voltage power supply</td>
			<td>Spellman</td>
			<td>CZE 1000R</td>
			<td>output voltage: 0-30 kV</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">scanning electron microscope&#160;</td>
			<td>JEOL-USA</td>
			<td>JSM-7400F</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">desk gold sputter coater</td>
			<td>Denton Vacuum</td>
			<td>DSK00V-0013</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Doppler laser vibrometer&#160;</td>
			<td>Polytec</td>
			<td>PDV-100</td>
			<td>non-contact velocity measurement (0-22 kHz)</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">PCR sequence detection system&#160;</td>
			<td>Applied Biosystems</td>
			<td>ABI7300</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">multiphoton confocal microscope</td>
			<td>Zeiss</td>
			<td>Zeiss 510Meta NLO</td>
			<td></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;">UV-VIS Spectrophotometer&#160;</td>
			<td style="width:188px;">NanoDrop Products 
			via Thermo Scientific</td>
			<td>ND-2000</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">VibSoft Data Acquisition Software</td>
			<td>Polytec</td>
			<td></td>
			<td>acquisition bandwidth up to 40 MHz</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Origin 8.5 data analysis software&#160;</td>
			<td>OriginLab</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">qbasePlus qPCR data analysis software&#160;</td>
			<td>Biogazelle</td>
			<td>V2.3</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">aluminium alloy&#160;</td>
			<td>McMaster-Carr</td>
			<td>Alloy 6061</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">acrylic blocks</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;">polycarbonate anti-humidity chamber</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td style="width:293px;">Impact-Resistant&#160;Polycarbonate</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">screws&#160;</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">electronic cable/wire</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">medical grade PVC tubing</td>
			<td>US Plastic Corp.</td>
			<td>Tygon S-50-HL</td>
			<td>clear, biocompatible</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">10 mL syringe&#160;</td>
			<td>Becton Dickinson</td>
			<td>309604</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">21 G blunt ended needle</td>
			<td>Small Parts</td>
			<td>NE-213PL-25</td>
			<td>1-1/2&#34; length</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">Alligator clip adapters&#160;</td>
			<td>RadioShack</td>
			<td>270-354</td>
			<td>fully insulated</td>
		</tr>
		<tr height="17">
			<td height="17" style="height:17px;">8 mm biopsy punch</td>
			<td><a href="http://www.sklarcorp.com/ProductListUS.aspx?DepartmentID=10&amp;CategoryID=96">Sklar&#160;Surgical Instruments</a></td>
			<td>96-1152</td>
			<td>sterile, disposable</td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">12 mm biopsy punch</td>
			<td>Acuderm (via Fisher Scientific)</td>
			<td style="width:124px;">NC9998681</td>
			<td></td>
		</tr>
		<tr height="16">
			<td height="16" style="height:17px;">tissue culture flasks</td>
			<td>Corning</td>
			<td></td>
			<td>cell culture treated</td>
		</tr>
	</tbody>
</table>

construction and characterization of a novel vocal fold bioreactor

In vitro engineering of mechanically active tissues requires the presentation of physiologically relevant mechanical conditions to cultured cells. To emulate the dynamic environment of vocal folds, a novel vocal fold bioreactor capable of producing vibratory stimulations at fundamental phonation frequencies is constructed and characterized. The device is composed of a function generator, a power amplifier, a speaker selector and parallel vibration chambers. Individual vibration chambers are created by sandwiching a custom-made silicone membrane between a pair of acrylic blocks. The silicone membrane not only serves as the bottom of the chamber but also provides a mechanism for securing the cell-laden scaffold. Vibration signals, generated by a speaker mounted underneath the bottom acrylic block, are transmitted to the membrane aerodynamically by the oscillating air. Eight identical vibration modules, fixed on two stationary metal bars, are housed in an anti-humidity chamber for long-term operation in a cell culture incubator. The vibration characteristics of the vocal fold bioreactor are analyzed non-destructively using a Laser Doppler Vibrometer (LDV). The utility of the dynamic culture device is demonstrated by culturing cellular constructs in the presence of 200-Hz sinusoidal vibrations with a mid-membrane displacement of 40 &#181;m. Mesenchymal stem cells cultured in the bioreactor respond to the vibratory signals by altering the synthesis and degradation of vocal fold-relevant, extracellular matrix components. The novel bioreactor system presented herein offers an excellent in vitro platform for studying vibration-induced mechanotransduction and for the engineering of functional vocal fold tissues.

The PCL scaffolds fabricated by electrospinning contain micron sized interstitial pores and randomly entangled fibers with an average diameter of 4.7 &#181;m (Figure&#160;4A). At a higher magnification, nanoscale grooves and pores are visible on individual fibers (Figure&#160;4B). Coating of the scaffolds with fibronectin improves hydrophilicity and facilitates the initial cell adhesion/spreading on the PCL scaffold (unpublished observation).
Sinusoidal wavefo...

Watch this Scientific Journal Video about Construction and Characterization of a Novel Vocal Fold Bioreactor at JoVE.com

Construction and Characterization of a Novel Vocal Fold Bioreactor

A novel vocal fold bioreactor capable of delivering physiologically relevant, vibratory stimulation to cultured cells is constructed and characterized. This dynamic culture device, when combined with a fibrous poly(&#949;-caprolactone) scaffold, creates a vocal fold-mimetic environment that modulates the behaviors of mesenchymal stem cells.

In vitro engineering of mechanically active tissues requires the presentation of physiologically relevant mechanical conditions to cultured cells. To ...

Research

JoVE Journal

Bioengineering

Engineering Biological-Based Vascular Grafts Using a Pulsatile Bioreactor

Much effort has been devoted to develop and advance the methodology to regenerate functional small-diameter arterial bypasses. In the physiological ...

Synthetic, Multi-Layer, Self-Oscillating Vocal Fold Model Fabrication

Sound for the human voice is produced via flow-induced vocal fold vibration. The vocal folds consist of several layers of tissue, each with differing ...

Design of a Biaxial Mechanical Loading Bioreactor for Tissue Engineering

We  designed a loading device that is capable of applying uniaxial or biaxial  mechanical strain to a tissue engineered biocomposites fabricated for  ...

Operation of a Benchtop Bioreactor

Fermentation systems are used to provide an optimal growth environment for many different types of cell cultures. The ability afforded by fermentors to ...

Nonhuman Primate Lung Decellularization and Recellularization Using a Specialized Large-organ Bioreactor

There are an insufficient number of lungs available to meet current and future organ transplantation needs. Bioartificial tissue regeneration is an ...

Investigating the Three-dimensional Flow Separation Induced by a Model Vocal Fold Polyp

The fluid-structure energy exchange process for normal speech has been studied extensively, but it is not well understood for pathological conditions. ...

Characterization of Leukocyte-platelet Rich Fibrin, A Novel Biomaterial

Autologous platelet concentrates represent promising innovative tools in the field of regenerative medicine and have been extensively used in oral ...

A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Past ...

Construction and Setup of a Bench-scale Algal Photosynthetic Bioreactor with Temperature, Light, and pH Monitoring for Kinetic Growth Tests

The optimal design and operation of photosynthetic bioreactors (PBRs) for microalgal cultivation is essential for improving the environmental and economic ...

Preparation and Characterization of Novel HDL-mimicking Nanoparticles for Nerve Growth Factor Encapsulation

The objective of this article is to introduce preparation and characterization methods for nerve growth factor (NGF)-loaded, high-density, lipoprotein ...