HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Pascal Maria Dohmen Wolfgang Konertz Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Dohmen, P. M. Articles by Konertz, W. Search for Related Content PubMed PubMed Citation Articles by Dohmen, P. M. Articles by Konertz, W. Related Collections Valve disease Related Article

Ann Thorac Surg 2006;81:1942
© 2006 The Society of Thoracic Surgeons

---

Correspondence

Seeding Human Endothelial Cells on Complex Three-Dimensional Scaffolds

Department of Cardiovascular Surgery, Charite Schumannstrasse 20/21 Berlin, D-10117 Germany

(Email: pascal.dohmen{at}charite.de).

To the Editor:

We have read the article by Gulbins and associates [1] regarding a seeding device and procedure for complex three-dimensional scaffolds with great attention and interest. It was nice to read that the sedimentation seeding technique that we used for several years in a juvenile sheep model [2, 3], and later clinically, is effective [4]. From a scientific point of view we are pleased that this technique was successfully reproduced by other investigators. The sedimentation technique showed 74% endothelial cell adhesion, whereas we achieved an effective endothelial cell adhesion rate of 91% under cell culture conditions (37°C, 5% CO₂ and 98% air saturation). We used fluorescence electron microscopy to verify complete, confluent seeding and maturation.

The author describes a bioreactor for cell seeding and the method used to calculate endothelial cells binding the allograft that are similar to those we previously used [4]. However there is a difference. With the Gulbins device endothelial cells can attach to the bottom of the bioreactor at the end of the seeding. If this happens it is difficult to calculate the exact number of cells binding to the matrix. For this reason we used a bio-inert material that was shown to prevent cell binding to the bioreactor.

During the last decade there has been a lot of revolutionary work done regarding tissue engineering for cardiovascular diseases. The key issue is to develop a sufficient scaffold to which to seed autologous cells. Several possible scaffolds types have been investigated; however for the moment the biological scaffold is the only matrix that is able to maintain optimal valve function. Contrary to the author, we believe heart valves must be decellularized prior to seeding. We agree with the author that most endothelial cells on allografts will be lost before or during implantation, as described by Crescenzo and colleagues [5].

Da Costa and colleagues [6] performed a study to show the differences between regular and decellularized cryopreserved allografts, which lack interstitial cells in patients. In patients, immunogenicity was significantly reduced after allograft decellularization and hemodynamics were improved.

We now have 4.5 years of clinical follow-up using autologous endothelial cell seeding on allografts implanted into the right ventricular outflow tract. The clinical course of the first patient was published in The Annals of Thoracic Surgery [4]. In total our group has experience with more than 200 implants of tissue-engineered heart valves from allogenic or xenogenic sources. We believe this new technology has great advantages, as shown by the excellent mid-term results [7, 8]. Long-term follow-up is ongoing.

	References

Top References

 

1. Gulbins H, Pritisanac A, Uhlig A, et al. Seeding of human endothelial cells on valve containing aortic mini-rootsdevelopment of a seeding device and procedure. Ann Thorac Surg 2005;79:2119-2126.[Abstract/Free Full Text]
2. Dohmen PM, Ozaki S, Verbeken E, Yperman J, Flameng W, Konertz W. Tissue engineering of a pulmonary xenograft heart valve Asian Cardiovasc Thoracic Surg 2002;10(1):25-30.
3. Dohmen PM, da Costa F, Lopes SV, et al. The juvenile sheep model for evaluation of tissue engineered cardiovascular grafts La Arch Cardiovasc Sci 2003;4:45-53.
4. Dohmen PM, Kivelitz D, Hotz H, Konertz W. Ross operation with a tissue engineered heart valve Ann Thorac Surg 2002;74:1438-1442.[Abstract/Free Full Text]
5. Crescenzo DG, Hilbert SL, Barrick MK, et al. Donor heart valveselectron microscopic and morphometric assessment of cellular injury induced by warm ischemia. J Thorac Cardiovasc Surg 1992;103:253-257.[Abstract]
6. da Costa FDA, Dohmen P, Duarte D, et al. Immunological and echocardiographic evaluation of decellularized versus cryopreserved homografts during Ross procedure Eur J Cardiothorac Surg 2005;27:572-578.[Abstract/Free Full Text]
7. Konertz W, Dohmen PM, Liu J, et al. Hemodynamic characteristics of the Matrix P decellularized xenograft for pulmonary valve replacement during Ross operation J Heart Valve Dis 2005;14:78-81.[Medline]
8. Dohmen PM, Ozaki S, Verbeken E, Yperman J, Flameng W, Konertz W. Tissue engineering of a pulmonary xenograft heart valve Asian Cardiovasc Thoracic Surg 2002;10(1):25-30.

This article has been cited by other articles:

				Reply. Ann. Thorac. Surg., May 1, 2006; 81(5): 1942 - 1943. [Full Text] [PDF]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Pascal Maria Dohmen Wolfgang Konertz Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Dohmen, P. M. Articles by Konertz, W. Search for Related Content PubMed PubMed Citation Articles by Dohmen, P. M. Articles by Konertz, W. Related Collections Valve disease Related Article