Background: The goal is to evaluate the microbial sterility of mesenchymal progenitor cells (MPCs)-derived from osteoarthritis (OA) and rheumatoid arthritis (RA) articular cartilages.
Methods: Contaminants, including bacteria and fungi in MPC cultures were initially evaluated by inoculation culture methods and then affirmed through the amplification of 16S ribosomal DNA (rDNA) and internally transcribed spacer (ITS) regions, respectively, using polymerase chain reaction (PCR). Further, the mollicutes, if any, were identified by genus-specific 16S rDNA, and the positive samples were reamplified using species-specific primers.
Results: No bacteria or fungi were found to be compromising the sterility of MPCs (n = 20) assessed by both traditional culture methods and PCR. However, two in early passages and three in later passages of MPCs had the presence of mollicutes. Further rescreening for species of mollicutes indicated the presence of Mycoplasma hyorhinis, M. salivarium, and M. arginine.
Conclusions: The PCR methods employed in this study could be beneficial as a rapid sterility testing of cell lines.