Human articular chondrocytes on macroporous gelatin microcarriers form structurally stable constructs with blood-derived biological gluesin vitro

Abstract

Biodegradable macroporous gelatin microcarriers fixed with blood-derived biodegradable glue is proposed as a delivery system for human autologous chondrocytes. Cell-seeded microcarriers were embedded in four biological gluesrecalcified citrated whole blood, recalcified citrated plasma with or without platelets, and a commercially available fibrin glue -and cultured in an in vitro model under static conditions for 16 weeks. No differences could be verified between the commercial fibrin glue and the blood-derived alternatives. Five further experiments were conducted with recalcified citrated platelet rich plasma alone as microcarrier sealant, using two different in vitro culture models and chondrocytes from three additional donors. The microcarriers were found chondrocyte adhesion and expansion, as well as extracellular matrix synthesis. Matrix formation occurred predominantly at sample surfaces under the static conditions. The presence of microcarriers proved essential for the glues to support the structural takeover of extracellular matrix proteins produced by the embedded chondrocytes, as exclusion of the microcarriers resulted in unstable structures that dissolved before matrix formation could occur. Immunohistochemical analysis revealed presence of SOX-9 and S-100 positive chondrocytes as well as production of aggrecan and collagen type I, but not of the cartilage-specific collagen type II. These results imply that blood-derived glues are indeed potentially applicable for encapsulation of chondrocyte-seeded microcarriers. However, the static in vitro models used in this study proved incapable of supporting cartilage formation throughout the engineered constructs.3

Effect of PRP and PPP on proliferation and migration of human chondrocytes and synoviocytes in vitro

“…Some authors have reported that PRP at higher concentrations failed to promote proliferation, and in some cases even suppressed it [14,30]. On the other hand, there are only a few studies on the effect of different concentrations of PRP on the proliferation of human chondrocytes [9,31,32] and synoviocytes [33]. The results of our proliferation assay indicated that PRP is capable of inducing proliferation of both cell types.…”

The effect of platelet-rich plasma on osteochondral defects treated with mosaicplasty

“…Contrary to these studies, however, Kon et al reported that PRP decreased the type II collagen content of cartilage repair tissue and worsened the gross appearance [38]. In addition, although many positive results have been reported, there have also been unpredictable results, due to variable platelet concentrations in solutions and different preparation techniques [9,40,41,42]. Nevertheless, in a very recent review by Sheth et al, they attributed uncertain results for orthopaedic indications to a lack of standardization of outcome measures, PRP production, and investigative protocols [42,43].…”

“…In addition, although many positive results have been reported, there have also been unpredictable results, due to variable platelet concentrations in solutions and different preparation techniques [9,40,41,42]. Nevertheless, in a very recent review by Sheth et al, they attributed uncertain results for orthopaedic indications to a lack of standardization of outcome measures, PRP production, and investigative protocols [42,43]. In order to overcome these limitations and standardize the preparation of PRP, we used the same manufacturer's kits; thus, we avoided creating a misleading factor, and we achieved an increase of at least four to five times over baseline platelet numbers, which was suggested as a sufficient cellular response by Marx [44].…”

Cell expansion of human articular chondrocytes on macroporous gelatine scaffolds—impact of microcarrier selection on cell proliferation

“…The ability of this class of scaffold to support human chondrocyte growth is well known, yet to our knowledge this is the first time that a comparison between these four specific microcarriers has been conducted (Huss et al, 2007;Malda et al, 2003a;Pettersson et al, 2009;Schrobback et al, 2011).…”

“…We have previously proposed the use of gelatine microcarriers in combination with platelet rich plasma as a delivery system for tissue engineering of cartilage using both human dermal fibroblasts, subjected to chondrogenic induction media, and human articular chondrocytes (Sommar et al, 2009;. Other investigators have also used this type of microcarrier in combination with human chondrocytes (Malda et al, 2003a;Pettersson et al, 2009;Huss et al, 2007;Schrobback et al, 2011).…”