Abstract:
OBJECTIVE To evaluate the application potential of next-generation sequencing(NGS) for detecting adventitious agent contamination, including viruses, bacteria, and fungi, in biological products and to systematically compare the detection performance of Kraken2 and Sylph.
METHODS Human serum albumin was used as the matrix and spiked with different concentrations of Hepatitis B virus(HBV), Pseudomonas paraeruginosa, Bacillus spizizenii and Aspergillus brasiliensis. The samples were subjected to NGS, and Kraken2 and Sylph were used for taxonomic classification and relative abundance analysis. The limits of detection and detection sensitivities of the 2 tools were evaluated, and their detection profiles for non-target taxa were compared.
RESULTS With a data volume of 0.5M(500000) sequences, the detection limit of Kraken2 for HBV was 1×105 copies·mL−1, and the detection limits for P. paraeruginosa, B. spizizenii and A. brasiliensis were 1, 100, 100 CFU·mL−1, respectively. The detection limit for HBV using Sylph was 1×107 copies·mL−1. The detection limits for P. paraeruginosa, B. spizizenii and A. brasiliensis were 1×104, 1×104, 1×105 CFU·mL−1, respectively. Non-target taxa were detected in the negative controls. In various sequencing data volumes, the detection limit of Kraken2 for HBV was 1×105 copies·mL−1, and the detection limits for P. paraeruginosa, B. spizizenii and A. brasiliensis were 1, 10, 10 CFU·mL−1, respectively. The detection limit for HBV using Sylph was 1×105 copies·mL−1. The detection limits for P. paraeruginosa, B. spizizenii and A. brasiliensis were 100, 1×103, 1×104 CFU·mL−1, respectively.
CONCLUSION Kraken2 showed higher detection sensitivity than Sylph but also detected more non-target taxa. Overall, NGS technology can simultaneously detect multiple categories of adventitious agents in biological products. By optimizing the sequencing process and combining the multi-tool cross-validation strategy, the detection reliability is significantly improved. NGS technology is expected to become an effective means of quality control of biological products.