Many cell substrates currently used for recombinant DNA products, monoclonal antibodies and some vaccines are abnormal in that these cells are either tumorigenic or are actually derived from tumors. During the manufacturing of products from these cell culture systems, cell lysis may take place. Therefore, host cell DNA possibly containing an oncogene(s) may be present in the product, which may lead to a tumorigenic event in the recipient. Production schemes generally include purification procedures that remove the nucleic acids; however, it is still necessary to verify the amount of residual host DNA present in intermediate and final product samples.
Charles River uses highly sensitive methods to detect and quantify minute amounts of residual host cell DNA. From the nonspecific detection of total DNA to the detection of species-specific target sequences, we offer the following methods:
- Threshold Assay - uses DNA binding-proteins with high affinity for single-stranded DNA for nonspecific quantification of total DNA
- Hybridization Assay - a hybridization-based method for the detection of specific DNA of defined origin
- qPCR Assay - a quantitative PCR-based method for the detection of specific DNA of defined origin; targets a specific gene sequence for amplification