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 Cardiac - other Valve disease Related Article

---

Correspondence

Decellularization of Xenogenic Biologic Tissue

Charite, Medical University Berlin, Department of Cardiovascular Surgery, Luisenstrasse 13, D-10117 Berlin, Germany

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

To the Editor:

We were interested in the article by Ota and colleagues [1] in which they reported "a novel method of decellularization of porcine heart valves using polyethylene glycol and gamma irradiation." The demonstrations were excellent, but we would like to comment on some other issues.

The authors' conclusion that decellularization of xenogenic implants has only poor results and outcomes remains controversial. The authors referred to an article published in 2003 about the SynerGraft (CryoLife Inc, Kennesaw, GA) technology, which seems to induce major structural damage to the important extracellular matrix.

In recent years, newer techniques and methods have been applied successfully, including chemical and enzymatic methods as well as protease inhibitors, and demonstrated reliable results [2]. In 2006, our group [3–5] introduced a decellularization technique for xenogenic tissue using desoxycholic acid in combination with ethanol. Complete decellularization of the xenogenic tissue was achieved without any evidence of extracellular matrix destruction [6, 7]. In our judgement, generalizations of the efficacy of decellularization techniques should be avoided.

Furthermore their title may be misleading, because it suggests the valves are only treated with polyethylene glycol and gamma irradiation. In fact, gamma irradiation was not used to decellularize but to sterilize the decellularized scaffold. Ota and colleagues apparently added deoxyribonuclease as described in "Material and Methods," to achieve complete decellularization of the tissue. Although deoxyribonuclease is effective for the decellularization process, accumulated experimental evidence indicates that deoxyribonuclease also damages and alters the extracellular matrix [8].

The article by Ota and colleagues suggests that results of decellularized heart valves are presented. However, the authors used an aortic vascular graft, without a heart valve. To assess functionality of any decellularized technique for heart valves, it is absolutely essential to study valves because the structures of the aortic wall and valve tissue differ considerably.

Finally, we are concerned about the use of gamma irradiation, because previous reports by Cohen and colleagues [9] have demonstrated that this method may lead to leaflet alterations, including rupture and calcification.

	References

Top References

 

1. Ota T, Taketani S, Iwai S, et al. Novel method of decellularization of porcine valves using polyethylene glycol and gamma irradiation Ann Thorac Surg 2007;83:1501-1507.[Abstract/Free Full Text]
2. Rieder E, Kasimir M, Silberhumer, et al. Decellualrization protocols of porcine heart valves differ imortantly in efficiency of cell removal and susceptibility of the matrix to recellularization with human vascular cells J Thorac Cardiovasc Surg 2004;127:399-405.[Abstract/Free Full Text]
3. Erdbrügger W, Posner S, Ellerbrock H, et al. Deoxycholic acid treatment offers improved prospects in heart valve replacement Tiss Eng 2006;8:2059-2068.
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. Dohmen PM, Lembcke A, Holinski S, Braun JP, Pruss A, Konertz WF. Midterm clinical results using a tissue engineered pulmonary valve to reconstruct the right ventricular outflow tract during Ross procedure Ann Thorac Surg 2007;84:729-736.[Abstract/Free Full Text]
6. 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]
7. Dohmen PM, da Costa F, Lopes SV, et al. Is there a possibility for a glutaraldehyde-free porcine heart valve to grow ? Eur Surg Res 2006;38:54-61.[Medline]
8. Uchimura E, Sawa Y, Taketani S, et al. New method of preparing acellular cardiovascular grafts by decellularization with poly(ethylene glycol) J Biomed Mater Res A 2003;67:834-837.[Medline]
9. Cohen DJ, Myerowitz PD, Young WP, et al. The fate of aortic valve homografts 12 to 17 years after implantation Chest 1988;93:482-484.[Medline]

This article has been cited by other articles:

				T. Ota, Y. Okita, and Y. Sawa Reply Ann. Thorac. Surg., June 1, 2008; 85(6): 2163 - 2164. [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 Cardiac - other Valve disease Related Article