Name: co-transplantation of human ovarian tissue with engineered endothelial cells: a cell-based strategy combining accelerated perfusion with direct paracrine delivery
Uploaded: 2018-05-16T14:00:00
Description: Watch this Scientific Journal Video about Co-transplantation of Human Ovarian Tissue with Engineered Endothelial Cells: A Cell-based Strategy Combining Accelerated Perfusion with Direct Paracrine Deli

Omar Alexander Man for the illustrations. 
L.M. was supported by a Pilot Award from the Cornell Clinical and Translational Science Center and an ASRM research grant. 
The authors would like to thank James lab members for critical reading of the manuscript.

All procedures involving animal subjects have been approved by the Institutional Animal Care and Use Committee (IACUC) at Weill Cornell Medical College. All xenotransplantation experiments using ovarian tissue were performed in accordance with relevant guidelines and regulations. Human ovarian tissue was collected from patients scheduled for chemotherapy or radiotherapy for cancer treatment or prior bone marrow transplantation. The institutional review board (IRB) Committee of Weill Cornell Medical College approved the c...

<ol>
	<li>Siegel, R. L., Miller, K. D., Jemal, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+Statistics,+2017.">Cancer Statistics, 2017.</a> CA Cancer J Clin. 67 (1), 7-30 (2017).</li><li>Magelssen, H., Melve, K. K., Skjaerven, R., Fossa, 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=Parenthood+probability+and+pregnancy+outcome+in+patients+with+a+cancer+diagnosis+during+adolescence+and+young+adulthood.">Parenthood probability and pregnancy outcome in patients with a cancer diagnosis during adolescence and young adulthood.</a> Hum Reprod. 23 (1), 178-186 (2008).</li><li>Donnez, J., Dolmans, M. 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A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Follicular+somatic+cell+factors+and+follicle+development.">Follicular somatic cell factors and follicle development.</a> Reprod Fertil Dev. 23 (1), 32-39 (2011).</li><li>Dunlop, C. E., Anderson, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+regulation+and+assessment+of+follicular+growth.">The regulation and assessment of follicular growth.</a> Scand J Clin Lab Invest Suppl. 244, 13-17 (2014).</li><li>Durlinger, A. 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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=Outcomes+of+transplantations+of+cryopreserved+ovarian+tissue+to+41+women+in+Denmark.">Outcomes of transplantations of cryopreserved ovarian tissue to 41 women in Denmark.</a> Hum Reprod. 30 (12), 2838-2845 (2015).</li><li>Oktay, K., Newton, H., Aubard, Y., Salha, O., Gosden, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cryopreservation+of+immature+human+oocytes+and+ovarian+tissue:+an+emerging+technology?.">Cryopreservation of immature human oocytes and ovarian tissue: an emerging technology?.</a> Fertil Steril. 69 (1), 1-7 (1998).</li><li>Shultz, L. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+lymphoid+and+myeloid+cell+development+in+NOD/LtSz-scid+IL2R+gamma+null+mice+engrafted+with+mobilized+human+hemopoietic+stem+cells.">Human lymphoid and myeloid cell development in NOD/LtSz-scid IL2R gamma null mice engrafted with mobilized human hemopoietic stem cells.</a> J Immunol. 174 (10), 6477-6489 (2005).</li><li>Ramalingam, R., Rafii, S., Worgall, S., Brough, D. E., Crystal, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=E1(-)E4(+)+adenoviral+gene+transfer+vectors+function+as+a+&amp;#34;pro-life&amp;#34;+signal+to+promote+survival+of+primary+human+endothelial+cells.">E1(-)E4(+) adenoviral gene transfer vectors function as a &amp;#34;pro-life&amp;#34; signal to promote survival of primary human endothelial cells.</a> Blood. 93 (9), 2936-2944 (1999).</li><li>Seandel, 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=Generation+of+a+functional+and+durable+vascular+niche+by+the+adenoviral+E4ORF1+gene.">Generation of a functional and durable vascular niche by the adenoviral E4ORF1 gene.</a> Proc Natl Acad Sci U S A. 105 (49), 19288-19293 (2008).</li><li>Meirow, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortical+fibrosis+and+blood-vessels+damage+in+human+ovaries+exposed+to+chemotherapy.+Potential+mechanisms+of+ovarian+injury.">Cortical fibrosis and blood-vessels damage in human ovaries exposed to chemotherapy. Potential mechanisms of ovarian injury.</a> Hum Reprod. 22 (6), 1626-1633 (2007).</li><li>Assidi, 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=Identification+of+potential+markers+of+oocyte+competence+expressed+in+bovine+cumulus+cells+matured+with+follicle-stimulating+hormone+and/or+phorbol+myristate+acetate+in+vitro.">Identification of potential markers of oocyte competence expressed in bovine cumulus cells matured with follicle-stimulating hormone and/or phorbol myristate acetate in vitro.</a> Biol Reprod. 79 (2), 209-222 (2008).</li><li>Thakur, S. C., Datta, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Higher+expression+of+hyaluronan+binding+protein+1+(HABP1/p32/gC1qR/SF2)+during+follicular+development+and+cumulus+oocyte+complex+maturation+in+rat.">Higher expression of hyaluronan binding protein 1 (HABP1/p32/gC1qR/SF2) during follicular development and cumulus oocyte complex maturation in rat.</a> Mol Reprod Dev. 75 (3), 429-438 (2008).</li><li>Dolmans, M. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Short-term+transplantation+of+isolated+human+ovarian+follicles+and+cortical+tissue+into+nude+mice.">Short-term transplantation of isolated human ovarian follicles and cortical tissue into nude mice.</a> Reproduction. 134 (2), 253-262 (2007).</li><li>Amorim, C. 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=Impact+of+freezing+and+thawing+of+human+ovarian+tissue+on+follicular+growth+after+long-term+xenotransplantation.">Impact of freezing and thawing of human ovarian tissue on follicular growth after long-term xenotransplantation.</a> J Assist Reprod Genet. 28 (12), 1157-1165 (2011).</li><li>Kawamura, 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=Hippo+signaling+disruption+and+Akt+stimulation+of+ovarian+follicles+for+infertility+treatment.">Hippo signaling disruption and Akt stimulation of ovarian follicles for infertility treatment.</a> Proc Natl Acad Sci U S A. 110 (43), 17474-17479 (2013).</li><li>Suzuki, 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=Successful+fertility+preservation+following+ovarian+tissue+vitrification+in+patients+with+primary+ovarian+insufficiency.">Successful fertility preservation following ovarian tissue vitrification in patients with primary ovarian insufficiency.</a> Hum Reprod. 30 (3), 608-615 (2015).</li><li>Campbell, B. K., Clinton, M., Webb, 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+role+of+anti-M&#252;llerian+hormone+(AMH)+during+follicle+development+in+a+monovulatory+species+(sheep).">The role of anti-M&#252;llerian hormone (AMH) during follicle development in a monovulatory species (sheep).</a> Endocrinology. 153 (9), 4533-4543 (2012).</li><li>Donnez, J., 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=Restoration+of+ovarian+activity+and+pregnancy+after+transplantation+of+cryopreserved+ovarian+tissue:+a+review+of+60+cases+of+reimplantation.">Restoration of ovarian activity and pregnancy after transplantation of cryopreserved ovarian tissue: a review of 60 cases of reimplantation.</a> Fertil Steril. 99 (6), 1503-1513 (2013).</li><li>Ferreira, 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+effects+of+sample+size+on+the+outcome+of+ovarian+tissue+cryopreservation.">The effects of sample size on the outcome of ovarian tissue cryopreservation.</a> Reprod Domest Anim. 45 (1), 99-102 (2010).</li><li>Gavish, Z., Peer, G., Roness, H., Cohen, Y., Meirow, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Follicle+activation+and+'burn-out'+contribute+to+post-transplantation+follicle+loss+in+ovarian+tissue+grafts:+the+effect+of+graft+thickness.">Follicle activation and 'burn-out' contribute to post-transplantation follicle loss in ovarian tissue grafts: the effect of graft thickness.</a> Hum Reprod. 30 (4), 1003 (2015).</li><li>Donnez, J., Dolmans, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fertility+Preservation+in+Women.">Fertility Preservation in Women.</a> N Engl J Med. 377 (17), 1657-1665 (2017).</li><li>Salama, M., Woodruff, T. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+advances+in+ovarian+autotransplantation+to+restore+fertility+in+cancer+patients.">New advances in ovarian autotransplantation to restore fertility in cancer patients.</a> Cancer Metastasis Rev. 34 (4), 807-822 (2015).</li><li>Donnez, J., Dolmans, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ovarian+cortex+transplantation:+60+reported+live+births+brings+the+success+and+worldwide+expansion+of+the+technique+towards+routine+clinical+practice.">Ovarian cortex transplantation: 60 reported live births brings the success and worldwide expansion of the technique towards routine clinical practice.</a> J Assist Reprod Genet. 32 (8), 1167-1170 (2015).</li><li>Meirow, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transplantations+of+frozen-thawed+ovarian+tissue+demonstrate+high+reproductive+performance+and+the+need+to+revise+restrictive+criteria.">Transplantations of frozen-thawed ovarian tissue demonstrate high reproductive performance and the need to revise restrictive criteria.</a> Fertil Steril. 106 (2), 467-474 (2016).</li><li>Kalich-Philosoph, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cyclophosphamide+triggers+follicle+activation+and+"burnout";+AS101+prevents+follicle+loss+and+preserves+fertility.">Cyclophosphamide triggers follicle activation and "burnout"; AS101 prevents follicle loss and preserves fertility.</a> Sci Transl Med. 5 (185), 185ra162 (2013).</li><li>Kano, 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=AMH/MIS+as+a+contraceptive+that+protects+the+ovarian+reserve+during+chemotherapy.">AMH/MIS as a contraceptive that protects the ovarian reserve during chemotherapy.</a> Proc Natl Acad Sci U S A. 114 (9), E1688-E1697 (2017).</li></ol>

Here we demonstrate that co-transplantation of exECs provides a significant benefit to ovarian tissue viability and function following xenograft in mice. Standards for clinical application of ovarian tissue auto-transplantation for fertility preservation have not been set and the optimal parameters (size, transplantation site, duration of graft, etc.)32,33,34 for enhanced recovery of the follicular pool remain undefined...

Cancer remains among the leading causes of death in the developed world, yet decades of research have yielded significant progress for most types of cancer, and in some cases nearly doubled survival rates1. Unfortunately, chemotherapeutic agents are often gonadotoxic, depleting the reserve of primordial follicles in ovaries and reducing fertility2. This growing population can benefit from various methods of fertility preservation including oocyte and/or embryo cryopreservation, however, patients requiring prompt initiation of cancer therapy and pre-pubertal patients are ineligible for these options. As an alternative, some patients have chosen to cryopreserve ovarian tissue before undertaking their therapeutic regimen, and upon recovery and remission, auto-transplanting tissue to restore fertility3. Yet, to date, graft survival and follicular output following auto-transplantation remain relatively low4, mainly due to tissue ischemia and hypoxia5,6,7. Despite numerous efforts to improve the viability of ovarian cortical grafts using anti-oxidants8,9, pro-angiogenic cytokines10,11,12,13, or mechanical manipulations14, graft ischemia in a 5 to 7 day window post-transplant undermines the viability and survival of the graft7. To address this, we developed a cell-based strategy to facilitate anastomosis of host and graft vessels and thus hasten reperfusion of ovarian tissue.
In addition to the ischemic insult to grafted ovarian tissue in the post-transplant window, the disruption of inter-follicular signaling may contribute to depletion of the pool15,16. Because exogenous endothelial cells (ExECs) contribute to stable and functioning vessels in the periphery of the graft, they present a unique opportunity to convey a defined molecular input to transplanted tissue. As a proof of principle, ExECs were engineered to express super-physiological levels of Anti-Mullerian hormone (AMH), a member of the transforming growth factor beta (TGF&#946;) superfamily that has been shown to restrict follicular growth17. Comparison of follicular distribution in grafts co-transplanted with control and AMH-expressing cells verifies the biological activity and potency of engineered exECs.
In summary, by improving graft viability and suppressing premature mobilization of the follicular pool, this approach can increase the productivity of auto-transplanted ovarian tissue in patients undergoing fertility preservation. Moreover, the ExEC-based platform enables experimental interrogation of molecular regulators that have been implicated in follicular development.

<table>
	<tbody>
		<tr>
			<td>Leibovitz&#8217;s L-15 medium</td>
			<td>Gibco</td>
			<td>11415064</td>
			<td></td>
		</tr>
		<tr>
			<td>Antibiotic-Antimycotic</td>
			<td>Gibco</td>
			<td>15240062</td>
			<td>Anti-Anti X100</td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Sigma</td>
			<td>S 1888</td>
			<td></td>
		</tr>
		<tr>
			<td>Fibrinogen</td>
			<td>Sigma</td>
			<td>F 8630</td>
			<td>from bovine plasma</td>
		</tr>
		<tr>
			<td>Thrombin</td>
			<td>Sigma</td>
			<td>T 1063</td>
			<td>from human plasma</td>
		</tr>
		<tr>
			<td>DMSO</td>
			<td>Sigma</td>
			<td>D 2650</td>
			<td></td>
		</tr>
		<tr>
			<td>DMEM</td>
			<td>Gibco</td>
			<td>12491015</td>
			<td></td>
		</tr>
		<tr>
			<td>Enzyme Cell Detachment Medium</td>
			<td>Invitrogen</td>
			<td>00-4555-56</td>
			<td>Accutase</td>
		</tr>
		<tr>
			<td>Plastic paraffin film</td>
			<td>Bemis NA</td>
			<td></td>
			<td>Parafilm M</td>
		</tr>
		<tr>
			<td>Surgical paper tape 2.5 cm</td>
			<td>3M</td>
			<td>1530-1</td>
			<td>Micropore</td>
		</tr>
		<tr>
			<td>Surgical Paper tape 1.25 cm</td>
			<td>3M</td>
			<td>1530-0</td>
			<td>Micropore</td>
		</tr>
		<tr>
			<td>Perforated plastic Surgical tape 1.25 cm</td>
			<td>3M</td>
			<td>1527-0</td>
			<td>Transpore</td>
		</tr>
		<tr>
			<td>Monofilament Absorbable Suture</td>
			<td>Covidien</td>
			<td>UM-203</td>
			<td>Biosyn</td>
		</tr>
		<tr>
			<td>Braided Absorbable Suture</td>
			<td>Covidien</td>
			<td>GL-889</td>
			<td>Polysorb</td>
		</tr>
		<tr>
			<td>Povidone-iodine Solution USP 10%</td>
			<td>Purdue Products</td>
			<td>67618-153-01</td>
			<td>Betadine Solution Swab Stick</td>
		</tr>
		<tr>
			<td>Cryoviales</td>
			<td>Nunc</td>
			<td>377267</td>
			<td>CryoTube</td>
		</tr>
		<tr>
			<td>sterile ocular lubricant</td>
			<td>Dechra</td>
			<td>17033-211-38</td>
			<td>Puralube</td>
		</tr>
		<tr>
			<td>1.7 ml micro-centrifuge tube</td>
			<td>Denville</td>
			<td>C-2172</td>
			<td>Eppendorf</td>
		</tr>
		<tr>
			<td>Anasthesia system</td>
			<td>VetEquip</td>
			<td>V-1 table top system with scavenging</td>
			<td></td>
		</tr>
		<tr>
			<td>Endothelial cells</td>
			<td>Angiocrine Biosciences, Inc., San Diego, CA, USA</td>
			<td></td>
			<td>Isolated, transfected with E4-ORF- 1 and labeled endothelial cells</td>
		</tr>
		<tr>
			<td>Trichrome stain</td>
			<td>Sigma</td>
			<td>HT15-1kt</td>
			<td>Trichrome Stain (Masson) Kit</td>
		</tr>
		<tr>
			<td>Isolectin</td>
			<td>Invitrogen</td>
			<td>I32450</td>
			<td>isolectin GS-IB4 From Griffonia simplicifolia, Alexa Fluor&#8482; 647 Conjugate</td>
		</tr>
	</tbody>
</table>

co-transplantation of human ovarian tissue with engineered endothelial cells: a cell-based strategy combining accelerated perfusion with direct paracrine delivery

Infertility is a frequent side effect of chemotherapy and/or radiotherapy and for some patients, cryopreservation of oocytes or embryos is not an option. As an alternative, an increasing number of these patients are choosing to cryopreserve ovarian tissue for autograft following recovery and remission. Despite improvements in outcomes among patients undergoing auto-transplantation of cryopreserved ovarian tissue, efficient revascularization of grafted tissue remains a major obstacle. To mitigate ischemia and thus improve outcomes in patients undergoing auto-transplantation, we developed a vascular cell-based strategy for accelerating perfusion of ovarian tissue. We describe a method for co-transplantation of exogenous endothelial cells (ExECs) with cryopreserved ovarian tissue in a mouse xenograft model. We extend this approach to employ ExECs that have been engineered to constitutively express Anti-Mullerian hormone (AMH), thus enabling sustained paracrine signaling input to ovarian grafts. Co-transplantation with ExECs increased follicular volume and improved antral follicle development, and AMH-expressing ExECs promoted retention of quiescent primordial follicles. This combined strategy may be a useful tool for mitigating ischemia and modulating follicular activation in the context of fertility preservation and/or infertility at large.

To determine whether co-transplantation of ExECs provides a benefit to patients&#39; tissue, thawed ovarian cortical strips were divided into equal sized pieces and engrafted bilaterally into immuno-compromised, NOD scid gamma (NSG), mice. With one side embedded in a fibrin clot alone (no ECs) and the other containing ExECs (Figure 1a), each mouse served as its own control. ExECs were obtained via isolation of primary endothelium from human umbilical cords an...

Watch this Scientific Journal Video about Co-transplantation of Human Ovarian Tissue with Engineered Endothelial Cells: A Cell-based Strategy Combining Accelerated Perfusion with Direct Paracrine Deli

Co-transplantation of Human Ovarian Tissue with Engineered Endothelial Cells: A Cell-based Strategy Combining Accelerated Perfusion with Direct Paracrine Delivery

For some patients, the only option for fertility preservation is cryopreservation of ovarian tissue. Unfortunately, delayed revascularization undermines follicular viability. Here, we present a protocol to co-transplant human ovarian tissue with endothelial cells for utilization as a cell-based strategy combining accelerated perfusion with a direct paracrine delivery of bioactive molecules.

Infertility is a frequent side effect of chemotherapy and/or radiotherapy and for some patients, cryopreservation of oocytes or embryos is not an option. ...

The overall goal of this protocol is to xenograft cryopreserved human ovarian tissue in combination with engineered endothelial cells that accelerate re-perfusion and provide paracrine stimulus that modulates follicular activation within the graft. This method provides a cell-based means of improving post-transplant viability of cryopreserved ovarian tissue and more broadly, establishes a robust model system for interrogating molecular regulation of human folliculogenesis. The main advantage of this technique is that it uses a single vehicle that of endothelial cells to both mitigate ischemia and provide a sustained source of secreted factors to engraft the tissue.So this method provide global benefit for tissue viability. It can also provide insight into molecular regulators that have been implicated in follicular development. To make a fibrin clot, work quickly and add 360 microliters of HEPES buffer to 200 microliters of the fibrinogen stock solution.Gently pipette to mix and keep the tube on ice. In the second microfuge tube, prepare thrombin working solution by adding 148.7 microliters of DMEM to 50 microliters of thrombin stock solution. Gently pipette to mix.Then add 1.3 microliters of one mole per liter of calcium chloride. Gently pipette to mix and keep the sample on ice. Using the enzyme cell detachment medium Accutase, detach previously prepared engineered endothelial cells from the plate and transfer them to a third microfuge tube.Then, spin down the cells. Next, using a hemocytometer and a covered glass, count the cells. To calculate the number of cells needed for the engraftment, convert a 20, 000 times area of ovarian tissue into millimeter squared by using a ruler to measure the dimensions.The multiply the area by 20, 000 to determine the number of cells needed for the engraftment. Spin down the required cells. And use DMEM to re-suspend the pellet for a total volume of 16.8 microliters.Keep the cell suspension on ice. Next, place a piece of ovarian tissue on a sterile gauze sponge for a few seconds to dry it. Then transfer the tissue onto a previously prepared plastic paraffin film in a 50 millimeter petri dish.Add 39.2 microliters of the fibrinogen solution into the prepared cell suspension. Mix by gentle pipetting, and keep the suspension on ice. Then working quickly, add 14 microliters of the thrombin solution to the tube and gently pipette once to mix.Pipette the mixture on top of the ovarian tissue in the shape of an elongated droplet. Incubate the petri dish with the clot at 37 degrees Celsius. Work quickly once you have added the thrombin solution to the fibrinogen cell suspension.Synchronizing the future preparation in surgery is a challenge and it may be prudent to perform a practice run prior to expending precious human tissue. After anesthetizing the 10 to 14 week old female NSG mouse, and preparing it for surgery according to the text protocol, heat the animal and monitor the body temperature throughout the procedure. With a povidone iodine swab stick, clean the trimmed area and then use sterile alcohol to wipe it off.Next, place a drop of sterile ocular lubricant vet ointment over each of the mouse's eyes to protect them from dehydration and damage to the cornea. After performing a bilateral oophorectomy according to the text protocol, inject buprenorphine subcutaneous. Then make a horizontal incision in the fascia above the gluteus maximus at a length that fits the clot dimensions.Create a pocket within this virtual space by opening the scissors underneath the fascia. Pick up one piece of previously prepared encapsulated cortical tissue and place it in the pocket. Then use six O braided absorbable suture to suture the fascia before repeating the co-transplant on the contra-lateral side.Close the dorsal wall with four O monofilament absorbable suture in simple interrupted stitches. Inject lidocaine subcutaneous at the incision site. Then use a sterile alcohol prep to clean the skin and carry out post-operative care according to the text protocol.As seen here, two weeks after bilateral engraftment of E4-ORF1 treated human umbilical vein endothelial cells into NSG female mice, functionally perfused vessels formed from GFP labeled exogenous ECs or ExECs at the interface of host tissue and the graft. ExECs formed functional vessels when co-transplanted with ovarian tissue in cortical pieces co-transplanted with the mouse or human ExECs, increase the number of surviving follicles relative to control grafts. This increase in follicle development was associated with a decreased fibrotic area in ExEC assisted grafts.Final fibrotic area values were calculated for each graft as the average of three sections analyzed. Importantly, grafts that were co-transplanted with human foreskin fibroblasts showed poor tissue viability and relatively few follicles. 14 weeks after engraftment, mice were stimulated with menotropins.And the progression of follicle growth was monitored via MRI. Developing follicles were noted in both control and ExEC assisted grafts. However, more and larger sized follicles were noticed in the ExEC assisted grafts.Compared to antral follicles derived from the same patient's tissue, the granulosa cell layer in the more advanced follicle displayed increased expression of the ovulatory markers CD44 and HABP1, as well as increased cell death and reduced proliferation. After watching this video, you will understand how to perform co-transplantation of cryopreserved ovarian tissue with endothelial cells in a fibrin clot. And once mastered, you should be able to complete this protocol in less than one hour.Building on this approach, endothelial cells can be engineered to express any combination of secreted factors, thereby enabling interrogation of signaling pathways that may be relevant to fertility preservation, folliculogenesis, and/or tissue transplantation.

co-transplantation-human-ovarian-tissue-with-engineered-endothelial

Research

JoVE Journal

Bioengineering

Sensing of Barrier Tissue Disruption with an Organic Electrochemical Transistor

The gastrointestinal tract is an example of barrier tissue that provides a physical barrier against entry of pathogens and toxins, while allowing the passage of necessary ions and molecules. A breach in this barrier can be caused by a reduction in the extracellular calcium concentration. This reduction in calcium concentration causes a conformational change in proteins involved in the sealing of the barrier, leading to an increase of the paracellular flux. To mimic this effect the calcium chelator ethylene glycol-bis(beta-aminoethyl ether)-N,N,N&#39;,N&#39;-tetra acetic acid (EGTA) was used on a monolayer of cells known to be representative of the gastrointestinal tract. Different methods to detect the disruption of the barrier tissue already exist, such as immunofluorescence and&#160;permeability assays. However, these methods are time-consuming and costly and not suited to dynamic or high-throughput measurements. Electronic methods for measuring barrier tissue integrity also exist for measurement of the transepithelial resistance (TER), however these are often costly and complex. The development of rapid, cheap, and sensitive methods is urgently needed as the integrity of barrier tissue is a key parameter in drug discovery and pathogen/toxin diagnostics. The organic electrochemical transistor (OECT) integrated with barrier tissue forming cells has been shown as a new device capable of dynamically monitoring barrier tissue integrity. The device is able to measure minute variations in ionic flux with unprecedented temporal resolution and sensitivity, in real time, as an indicator of barrier tissue integrity. This new method is based on a simple device that can be compatible with high throughput screening applications and fabricated at low cost.

The Organic Electrochemical Transistor is integrated with live cells and used to monitor ion flux across the gastrointestinal epithelial barrier. In this study, an increase in ion flux, related to disruption of tight junctions, induced by the presence of the calcium chelator EGTA (ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetra acetic acid), is measured.

The gastrointestinal tract is an example of barrier tissue that provides a physical barrier against entry of pathogens and toxins, while allowing the ...

Tissue Engineering of Tumor Stromal Microenvironment with Application to Cancer Cell Invasion

3D organotypic cultures of epithelial cells on a matrix embedded with mesenchymal cells are widely used to study epithelial cell differentiation and invasion. Rat tail type I collagen and/or matrix derived from Engelbreth-Holm-Swarm mouse sarcoma cells have been traditionally employed as the substrates to model the matrix or stromal microenvironment into which mesenchymal cells (usually fibroblasts) are populated. Although experiments using such matrices are very informative, it can be argued that due to an overriding presence of a single protein (such as in type I Collagen) or a high content of basement membrane components and growth factors (such as in matrix derived from mouse sarcoma cells), these substrates do not best reflect the contribution to matrix composition made by the stromal cells themselves. To study native matrices produced by primary dermal fibroblasts isolated from patients with a tumor prone, genetic blistering disorder (recessive dystrophic epidermolysis bullosa), we have adapted an existing native matrix protocol to study tumor cell invasion. Fibroblasts are induced to produce their own matrix over a prolonged period in culture. This native matrix is then detached from the culture dish and epithelial cells are seeded onto it before the entire coculture is raised to the air-liquid interface. Cellular differentiation and/or invasion can then be assessed over time. This technique provides the ability to assess epithelial-mesenchymal cell interactions in a 3D setting without the need for a synthetic or foreign matrix with the only disadvantage being the prolonged period of time required to produce the native matrix. Here we describe the application of this technique to assess the ability of a single molecule expressed by fibroblasts, type VII collagen, to inhibit tumor cell invasion.

Tissue engineered fibroblast-derived native matrix is an emerging tool to generate a stromal substrate which supports epithelial cell proliferation and differentiation. Here a protocol applying this methodology to assess the impact of different stromal cell types on tumor cell biology is presented.

3D organotypic cultures of epithelial cells on a matrix embedded with mesenchymal cells are widely used to study epithelial cell differentiation and ...

Production, Characterization and Potential Uses of a 3D Tissue-engineered Human Esophageal Mucosal Model

The incidence of both esophageal adenocarcinoma and its precursor, Barrett&#8217;s Metaplasia, are rising rapidly in the western world. Furthermore esophageal adenocarcinoma generally has a poor prognosis, with little improvement in survival rates in recent years. These are difficult conditions to study and there has been a lack of suitable experimental platforms to investigate disorders of the esophageal mucosa.
A model of the human esophageal mucosa has been developed in the MacNeil laboratory which, unlike conventional 2D cell culture systems, recapitulates the cell-cell and cell-matrix interactions present in vivo and produces a mature, stratified epithelium similar to that of the normal human esophagus. Briefly, the model utilizes non-transformed normal primary human esophageal fibroblasts and epithelial cells grown within a porcine-derived acellular esophageal scaffold. Immunohistochemical characterization of this model by CK4, CK14, Ki67 and involucrin staining demonstrates appropriate recapitulation of the histology of the normal human esophageal mucosa.
This model provides a robust, biologically relevant experimental model of the human esophageal mucosa. It can easily be manipulated to investigate a number of research questions including the effectiveness of pharmacological agents and the impact of exposure to environmental factors such as alcohol, toxins, high temperature or gastro-esophageal refluxate components. The model also facilitates extended culture periods not achievable with conventional 2D cell culture, enabling, inter alia, the study of the impact of repeated exposure of a mature epithelium to the agent of interest for up to 20 days. Furthermore, a variety of cell lines, such as those derived from esophageal tumors or Barrett&#8217;s Metaplasia, can be incorporated into the model to investigate processes such as tumor invasion and drug responsiveness in a more biologically relevant environment.

This manuscript describes the production, characterization and potential uses of a tissue engineered 3D esophageal construct prepared from normal primary human esophageal fibroblast and squamous epithelial cells seeded within a de-cellularized porcine scaffold. The results demonstrate the formation of a mature stratified epithelium similar to the normal human esophagus.

The incidence of both esophageal adenocarcinoma and its precursor, Barrett&#8217;s Metaplasia, are rising rapidly in the western world. Furthermore ...

Delivery of Proteins, Peptides or Cell-impermeable Small Molecules into Live Cells by Incubation with the Endosomolytic Reagent dfTAT

Macromolecular delivery strategies typically utilize the endocytic pathway as a route of cellular entry. However, endosomal entrapment severely limits the efficiency with which macromolecules penetrate the cytosolic space of cells. Recently, we have circumvented this problem by identifying the reagent dfTAT, a disulfide bond dimer of the peptide TAT labeled with the fluorophore tetramethylrhodamine. We have generated a fluorescently labeled dimer of the prototypical cell-penetrating peptide (CPP) TAT, dfTAT, which penetrates live cells and reaches the cytosolic space of cells with a particularly high efficiency. Cytosolic delivery of dfTAT is achieved in multiple cell lines, including primary cells. Moreover, delivery does not noticeably impact cell viability, proliferation or gene expression. dfTAT can deliver small molecules, peptides, antibodies, biologically active enzymes and a transcription factor. In this report, we describe the protocols involved in dfTAT synthesis and cellular delivery. The manuscript describes how to control the amount of protein delivered to the cytosolic space of cells by varying the amount of protein administered extracellularly. Finally, the current limitations of this new technology and steps involved in validating delivery are discussed. The described protocols should be extremely useful for cell-based assays as well as for the ex vivo manipulation and reprogramming of cells.

We describe how to deliver proteins and cell-impermeable small molecules into cultured mammalian cells by a simple co-incubation protocol with a reagent that causes endocytic organelles to become leaky.

Macromolecular delivery strategies typically utilize the endocytic pathway as a route of cellular entry. However, endosomal entrapment severely limits the ...

Automated Contraction Analysis of Human Engineered Heart Tissue for Cardiac Drug Safety Screening

Cardiac tissue engineering describes techniques to constitute three dimensional force-generating engineered tissues. For the implementation of these procedures in basic research and preclinical drug development, it is important to develop protocols for automated generation and analysis under standardized conditions. Here, we present a technique to generate engineered heart tissue (EHT) from cardiomyocytes of different species (rat, mouse, human). The technique relies on the assembly of a fibrin-gel containing dissociated cardiomyocytes between elastic polydimethylsiloxane (PDMS) posts in a 24-well format. Three-dimensional, force-generating EHTs constitute within two weeks after casting. This procedure allows for the generation of several hundred EHTs per week and is technically limited only by the availability of cardiomyocytes (0.4-1.0 x 106/EHT). Evaluation of auxotonic muscle contractions is performed in a modified incubation chamber with a mechanical interlock for 24-well plates and a camera placed on top of this chamber. A software controls a camera moved on an XYZ axis system to each EHT. EHT contractions are detected by an automated figure recognition algorithm, and force is calculated based on shortening of the EHT and the elastic propensity and geometry of the PDMS posts. This procedure allows for automated analysis of high numbers of EHT under standardized and sterile conditions. The reliable detection of drug effects on cardiomyocyte contraction is crucial for cardiac drug development and safety pharmacology. We demonstrate, with the example of the hERG channel inhibitor E-4031, that the human EHT system replicates drug responses on contraction kinetics of the human heart, indicating it to be a promising tool for cardiac drug safety screening.

Here, we show the generation of human engineered heart tissue from induced pluripotent stem cells (hiPSC)-derived cardiomyocytes. We present a method to analyze contraction force and exemplary alteration of contraction pattern by the hERG channel inhibitor E-4031. This method shows high level of robustness and suitability for cardiac drug screening.

Cardiac tissue engineering describes techniques to constitute three dimensional force-generating engineered tissues. For the implementation of these ...

Perfusable Vascular Network with a Tissue Model in a Microfluidic Device

A spheroid (a multicellular aggregate) is regarded as a good model of living tissues in the human body. Despite the significant advancement in the spheroid cultures, a perfusable vascular network in the spheroids remains a critical challenge for long-term culture required to maintain and develop their functions, such as protein expressions and morphogenesis. The protocol presents a novel method to integrate a perfusable vascular network within the spheroid in a microfluidic device. To induce a perfusable vascular network in the spheroid, angiogenic sprouts connected to microchannels were guided to the spheroid by utilizing angiogenic factors from human lung fibroblasts cultured in the spheroid. The angiogenic sprouts reached the spheroid, merged with the endothelial cells co-cultured in the spheroid, and formed a continuous vascular network. The vascular network could perfuse the interior of the spheroid without any leakage. The constructed vascular network may be further used as a route for supply of nutrients and removal of waste products, mimicking blood circulation in vivo. The method provides a new platform in spheroid culture toward better recapitulation of living tissues.

The protocol describes how to engineer a perfusable vascular network in a spheroid. The spheroid's surrounding microenvironment is devised to induce angiogenesis and connect the spheroid to the microchannels in a microfluidic device. The method allows the perfusion of the spheroid, which is a long-awaited technique in three-dimensional cultures.

A spheroid (a multicellular aggregate) is regarded as a good model of living tissues in the human body. Despite the significant advancement in the ...

Microdissection of Primary Renal Tissue Segments and Incorporation with Novel Scaffold-free Construct Technology

Kidney transplantation is now a mainstream therapy for end-stage renal disease. However, with approximately 96,000 people on the waiting list and only one-fourth of these patients achieving transplantation, there is a dire need for alternatives for those with failing organs. In order to decrease the harmful consequences of dialysis along with the overall healthcare costs it incurs, active investigation is ongoing in search of alternative solutions to organ transplantation. Implantable tissue-engineered renal cellular constructs are one such feasible approach to replacing lost renal functionality. Here, described for the first time, is the microdissection of murine kidneys for isolation of living corticomedullary renal segments. These segments are capable of rapid incorporation within scaffold-free endothelial-fibroblast constructs which may enable rapid connection with host vasculature once implanted. Adult mouse kidneys were procured from living donors, followed by stereoscope microdissection to obtain renal segments 200 - 300 &#181;m in diameter. Multiple renal constructs were fabricated using primary renal segments harvested from only one kidney. This method demonstrates a procedure which could salvage functional renal tissue from organs that would otherwise be discarded.

Tissue-engineered renal constructs provide a solution for the organ shortage and deleterious effects of dialysis. Here, we describe a protocol to micro dissect murine kidneys for isolation of cortico-medullary segments. These segments are implanted into scaffold-free cellular constructs, forming renal organoids.

Kidney transplantation is now a mainstream therapy for end-stage renal disease. However, with approximately 96,000 people on the waiting list and only ...

A Novel Tenorrhaphy Suture Technique with Tissue Engineered Collagen Graft to Repair Large Tendon Defects

Surgical management of large tendon defects with tendon grafts is challenging, as there are a finite number of sites where donors can be readily identified and used. Currently, this gap is filled with tendon auto-, allo-, xeno-, or artificial grafts, but clinical methods to secure them are not necessarily translatable to animals because of the scale. In order to evaluate new biomaterials or study a tendon graft made up of collagen type 1, we have developed a modified suture technique to help maintain the engineered tendon in alignment with the tendon ends. Mechanical properties of these grafts are inferior to the native tendon. To incorporate engineered tendon into clinically relevant models of loaded repair, a strategy was adopted to offload the tissue engineered tendon graft and allow for the maturation and integration of the engineered tendon in vivo until a mechanically sound neo-tendon was formed. We describe this technique using incorporation of the collagen type 1 tissue engineered tendon construct.

In this paper, we present an in vitro and in situ protocol to repair a tendon gap of up to 1.5 cm by filling it with engineered collagen graft. This was performed by developing a modified suture technique to take the mechanical load until the graft matures into the host tissue.

Surgical management of large tendon defects with tendon grafts is challenging, as there are a finite number of sites where donors can be readily ...

Three-dimensional Patterning of Engineered Biofilms with a Do-it-yourself Bioprinter

Biofilms are aggregates of bacteria embedded in a self-produced spatially-patterned extracellular matrix. Bacteria within a biofilm develop enhanced antibiotic resistance, which poses potential health dangers, but can also be beneficial for environmental applications such as purification of drinking water. The further development of anti-bacterial therapeutics and biofilm-inspired applications will require the development of reproducible, engineerable methods for biofilm creation. Recently, a novel method of biofilm preparation using a modified three-dimensional (3D) printer with a bacterial ink has been developed. This article describes the steps necessary to build this efficient, low-cost 3D bioprinter that offers multiple applications in bacterially-induced materials processing. The protocol begins with an adapted commercial 3D printer in which the extruder has been replaced with a bio-ink dispenser connected to a syringe pump system enabling a controllable, continuous flow of bio-ink. To develop a bio-ink suitable for biofilm printing, engineered Escherichia coli bacteria were suspended in a solution of alginate, so that they solidify in contact with a surface containing calcium. The inclusion of an inducer chemical within the printing substrate drives expression of biofilm proteins within the printed bio-ink. This method enables 3D printing of various spatial patterns composed of discrete layers of printed biofilms. Such spatially-controlled biofilms can serve as model systems and can find applications in multiple fields that have a wide-ranging impact on society, including antibiotic resistance prevention or drinking water purification, among others.

This article describes a method of transforming a low-cost commercial 3D printer into a bacterial 3D printer that can facilitate printing of patterned biofilms. All necessary aspects of preparing the bioprinter and bio-ink are described, as well as verification methods to assess the formation of biofilms.

Biofilms are aggregates of bacteria embedded in a self-produced spatially-patterned extracellular matrix. Bacteria within a biofilm develop enhanced ...

Establishing Single-Cell Based Co-Cultures in a Deterministic Manner with a Microfluidic Chip

Cell co-culture assays have been widely used for studying cell-cell interactions between different cell types to better understand the biology of diseases including cancer. However, it is challenging to clarify the complex mechanism of intercellular interactions in highly heterogeneous cell populations using conventional co-culture systems because the heterogeneity of the cell subpopulation is obscured by the average values; the conventional co-culture systems can only be used to describe the population signal, but are incapable of tracking individual cells behavior. Furthermore, conventional single-cell experimental methods have low efficiency in cell manipulation because of the Poisson distribution. Microfabricated devices are an emerging technology for single-cell studies because they can accurately manipulate single cells at high-throughput and can reduce sample and reagent consumption. Here, we describe the concept and application of a microfluidic chip for multiple single-cell co-cultures. The chip can efficiently capture multiple types of single cells in a culture chamber (~46%) and has a sufficient culture space useful to study the cells&#39; behavior (e.g., migration, proliferation, etc.) under cell-cell interaction at the single-cell level. Lymphatic endothelial cells and oral squamous cell carcinoma were used to perform a single-cell co-culture experiment on the microfluidic platform for live multiple single-cell interaction studies.

This report describes a microfluidic chip-based method to set up a single cell culture experiment in which high-efficiency pairing and microscopic analysis of multiple single cells can be achieved.

Cell co-culture assays have been widely used for studying cell-cell interactions between different cell types to better understand the biology of diseases ...