A Deep Dive into Flow Cytometry

Precision-Driven Flow Cytometry: Advanced Technologies Ensuring Reliable Data for Complex Therapies.

All flow cytometry assays performed in C3i are qualified and/or validated. Depending on the assays, three instruments are currently used: FACS Lyric, FACS Canto, or Accellix. During the qualification/validation, accuracy is verified using a known control (where reference values have already been established). Reproducibility is only evaluated when another laboratory executes the same assay using the same method.

However, other parameters are evaluated during the qualification/validation, including precision (intra-assay and intermediate precision), linearity, and specificity.

Also, each assay includes an internal control to validate it during the routine test. The internal control must respect the criteria established during the qualification/validation or by the manufacturer.

In addition, two to three times per year, a part of our assays is evaluated with blind samples controlled by the accreditation CAP (College of American Pathologists). The results obtained on these blind samples are compared to those of other laboratories performing the same assay. Our results are “acceptable” if they are within the established range.

Currently, we use two flow cytometry technologies: manual cytometry with extracellular and intracellular staining using FACS Lyric and FACS Canto and semi-automatic technology using Accellix.

Case Study: Solving Critical Cell Therapy Hurdles Through Expert Flow Cytometry Insights.

C3i was challenged during the client’s clinical assay phase 1 projects. One example concerned an assay that had been fully validated for one project. This assay characterized T cells expressing a CAR-T specific for the antigen PSMA. The staining was based on the technology his-tag, where this staining was not the most adequate. During the study, the client asked to optimize this assay using better technology, such as staining with the sequence of biotinylation/streptavidin.

As the study could not be stopped to revalidate this assay, the QC team performed the release testing and revalidation simultaneously. A comparison between his-tag technology and biotinylation technology has been made for the first time. This comparison was executed during the release testing. Then, a complete assay validation using the biotinylation technology was performed while continuing the release testing.

The QC team has demonstrated that the client’s timeline can be respected without stopping the release testing activities.

End-to-End, Scalable Solutions: Differentiated Flow Cytometry Services Built for Speed, Compliance, and Customization.

C3i offers different flow cytometry services that respect regulatory requirements. It uses two technologies (manual or semi-automatic staining/acquisition). All assays performed in flow cytometry are minimum qualified or fully validated. Also, the instruments are FDA 21 CFR part 11 compliant.

C3i has a backup for each instrument to avoid stopping activities and can perform several tests simultaneously. In addition, C3i can execute the sorting cells using two technologies: the FACS Aria (using antibody coupled by fluorochrome) or the RoboSep (using antibody coupled by magnetic beads).