Abstract

Genetic Stability and Tumorigenicity within Chondrocyte Cultures using GTG, SKY and Locus-specific FISH

Heidrun Holland, Investigator, TRM Leipzig

The development of cell-based therapy raises the question whether the application of cell-based products to humans is safe. Therefore, it is important to determine whether the manufacturing process leads to chromosomal aberrations. In a preclinical study, we analyzed 360 chondrocyte samples (68 adherent cultures and 292 spheroids) from five donors using Trypsin-Giemsa staining (GTG-banding), spectral karyotyping (SKY), and locus-specific fluorescence in situ hybridization (FISH). Applying these techniques, the genetic analyses revealed no significant chromosomal instability for at least 3 passages. We detected clonal occurrence of polyploid metaphases and endomitoses with increasing cultivation time (passage 4-10). Y-chromosomal losses were identified in the two male donors with increasing frequency during the cultivation time. Interestingly, one donor showed trisomy of chromosomes 1,7,8,12, and translocation of chromosomes 7 and 9, which are also described for extraskeletal myxoid chondrosarcoma. Our results attest to the necessity of (molecular) cytogenetic analyses at certain cultivation times in preclinical studies. More investigations are needed to evaluate the potential tumorigenic risk for osteoarthritic patients to an extension of articular chondrocyte implantation.