Vergleichender Überblick über Verfahren zur Kultivierung artikulärer Chondrozyten

Zusammenfassung

Studienziel: In-vitro-Techniken für artikuläre Chondrozyten dienen nicht nur dem Studium pathophysiologischer Vorgänge sowie der Einflüsse von Mediatoren und Medikamenten zur Arthrose- bzw. Arthritisbehandlung, sondern auch der Herstellung von Knorpelersatzgewebe zur Defektauffüllung in vivo. Diese Arbeit soll einerseits einen Überblick über die Grundlagen verschiedener Techniken zur Kultivierung von Gelenkknorpelzellen geben, andererseits die spezifischen Anforderungen (phänotypische Stabilität mit Synthese von Aggrekan und Typ-II-Kollagen, fehlender direkter Zell-Zell-Kontakt, geringe Proliferationsneigung, geringer Umsatz der Matrixmoleküle) an solche Systeme aufzeigen. Methode: Anhand einer „Medline”-gestützten Recherche wurden die gegenwärtig verwendeten Techniken der Knorpelzellkultur und deren Entwicklung identifiziert. Die Bewertung erfolgte aufgrund eigener Erfahrungen und der in der Literatur angegebenen Daten. Ergebnisse: Es lassen sich zwei- und dreidimensionale Techniken zur Kultivierung von Gelenkknorpelzellen unterscheiden. Zweidimensionale (Monolayer-)Kulturen fördern insbesondere die Proliferation der Knorpelzellen, führen aber gleichzeitig innerhalb von Tagen zu einem Verlust des spezifischen Phänotyps artikulärer Chondrozyten. Dreidimensionale Anordnungen (z. B. Organ-, Alginat-, Agarosekulturen) gewährleisten nicht nur den Erhalt des Phänotyps über Monate, sondern erlauben (in Monolayer) dedifferenzierten artikulären Chondrozyten nach dem Transfer in eine dreidimensionale Umgebung die Wiederherstellung des ursprünglichen Phänotyps. Schlussfolgerung: Die Wahl der jeweiligen Methodik zur Kultivierung artikulärer Chondrozyten sollte an die zu beantwortende Fragestellung angepasst werden.

Abstract

Aim: In-vitro techniques for articular chondrocytes allow the analysis of their metabolism in the presence and absence of mediators or drugs against osteoarthritis or rheumatoid arthritis, as well as the synthesis of de-novo cartilage tissue for implantation into articular defects in vivo. This review aims to give an overview about the basics of different methods of cultivation of articular chondrocytes and about several specific demands (e.g., phenotypical stability with synthesis of aggrecan and type-II collagen, no cell-to-cell contact, low proliferation rates, low matrix molecule turn-over) to such methods. Method: Current techniques for the cultivation of articular chondrocytes and their development were identified via “medline”. Their evaluation was based on our own experience and on data from the literature. Results: Two- and three-dimensional culture systems are employed to maintain articular chondrocytes in vitro. Two-dimensional cultures (monolayer) support the proliferation of articular chondrocytes, but lead to a de-differentiation to fibroblast-like cells. Three-dimensional set-ups (e.g., organ, alginate, agarose cultures) not only maintain the articular cartilage phenotype, but they also support the re-differentiation of de-differentiated chondrocytes. Conclusion: The choice of a culture system for in-vitro studies with articular chondrocytes should be adapted to the question asked.

Schlüsselwörter

Artikuläre Chondrozyten - Gelenkknorpel - in vitro - Kultur - Phänotyp

Key words

Articular chondrocytes - articular cartilage - in-vitro - tissue culture - phenotype

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