Identification of newly established Spodoptera littoralis cell lines by two DNA barcoding markers.

Cell line authentication is crucial in determining the identity of cell lines and detecting any cross-contamination. The identity of three newly established Spodoptera littoralis cell lines (Spli-C, Spli-B, and Spli-S) was confirmed by DNA fingerprinting. In this study, we used two universal primers sets to amplify two DNA fragments in different positions in the mitochondrial cytochrome C oxidase 1 gene (COI). The PCR reaction succeeded in amplifying two target DNA amplicons. The first amplicon had ~650 bp, while the second had ~410 bp. By comparing the obtained informative sequences with those in the GenBank sequence database, the results showed 100% similarity between the S. littoralis cell lines and their host. The same similarity ratio was observed between the Sf21, Tni, and Cp cell lines, which are used widely, and their hosts. The informative sequences were then used for phylogenetic analyses. In addition to the high efficiency of this technique, it showed high reproducibility in two different laboratories. DNA barcoding using the two sets of the universal primers used in this study can be a fast and a reliable method for insect cell line identification.