138-P

Abstract

The FDA has issued new draft guidance on molecular testing around Research Use Only (RUO) and non-Quality System Regulation (QSR) products in clinical labs. Promega has introduced a new QSR-compliant nucleic acid extractor and kit specifically to address this issue. At BloodCenter of Wisconsin we have evaluated this new extractor, the Maxwell ® CSC, in terms of its performance in HLA typing assays as well as its fit in the molecular HLA workflow. Patient samples (buccal swabs) were extracted using the Maxwell ® CSC, and then evaluated for total yield and purity of DNA. They were compared to the existing extraction method and evaluated by sequence-based typing, rSSO and STR assays for overall success and results concordance. The data handling capabilities of the instrument were also evaluated, such as how the run reports affected technician time, downstream operations and integration with electronic records. DNA concentrations from double-buccal swab isolations ranged from 13 ng/μl to 247 ng/μl, with a mean concentration of 76.31 ng/μl. DNA purities ranged from OD260/280 ratios of 1.69 to 2.00, with a mean of 1.89. These results are comparable to those obtained on the Maxwell ® MDx instrument in our laboratory. All samples tested in downstream HLA STR assay, KIR rSSO, HLA rSSO and sequence-based typing assays were successful and concordant with previously obtained results. The Maxwell ® CSC is a QSR-compliant system which will allow molecular laboratories to adhere to the draft FDA guidance for molecular testing. It provides a solution for nucleic acid extraction which performs equivalently to Promega’s current extraction systems with regards to DNA yield, quality and utility in downstream assays. The Maxwell® CSC also helps reduce data entry tasks with exportable sample-specific results. This is useful for tracking samples throughout the workflow, reducing the need to re-enter sample identifiers, saving technicians time and reducing errors.