Transcriptome-wide analysis of human chondrocyte expansion on synoviocyte matrix. Homo sapiens isolate:Donor1 TCP P1

Human chondrocytes, expanded and used in autologous chondrocyte implantation techniques, are known to rapidly de-differentiate in culture. These chondrocytes undergo both morphological and phenotypical changes and, eventually, lose the ability to produce hyaline-like matrix when cultured on tissue culture (TC) plastic. Growth on synoviocyte-derived extracellular matrix (SDECM) reduces this de-differentiation allowing for more than double the number of population doublings whilst retaining chondrogenic capacity. The goal of this study was to use RNAseq analysis to examine the differences between TC plastic-expanded and SDECM-expanded human chondrocytes over 4 passages. Human chondrocytes (3 donors) were thawed from primary stocks collected under an IRB approved protocol and cultured on TC plastic flasks or on SDECM-coated flasks at physiological oxygen tension (5%) for 4 passages. RNA was extracted from the cell layer during log expansion (70-90% confluence) phase at passages 1 and 4, column purified and DNAse treated before QC analysis and submitted for next generation RNA sequencing (RNAseq). Significant effects on gene expression were observed due to both growth substrates and passage number. These results may provide insight into the mechanism of how SDECM provides a more chondrogenesis perserving environment for cell expansion.