Flow Cytometer Characterization, Standardization and Assay Validation for Vaccine Clinical Trial Testing

About the Speaker

Katharine Schwedhelm, Ph.D is a research manager for the HIV Vaccine Trials Network (HVTN) Endpoints laboratory at Fred Hutchinson Cancer Center in Seattle, WA. She gained experience in flow cytometry and instrumentation at Benaroya Research Institute before moving to Fred Hutch, where her focus has been directed towards high parameter panel development to support HIV and COVID-19 vaccine studies and cytometer standardization and characterization. Katharine also supports the Cape Town HVTN laboratory, facilitating panel transfers and ensuring cross-lab assay and instrument concordance, and has been an instructor at the African Flow Cytometry Workshop.

Webinar Summary

Flow cytometry is a powerful tool for monitoring immune function. However, to be most effective, the instruments must be thoroughly characterized and standardized. At the HIV Vaccine Trials Network (HVTN) cellular laboratory, our rigorous quality control procedure that ensures optimal instrument functioning and establishes standardized target MFI values results in interchangeable flow cytometers, minimization of batch-to-batch variation, and consistent and high-quality data. 

In response to efforts to combat the SARS-CoV-2 pandemic through a safe and efficacious vaccine, the HVTN/COVID-19 Prevention Trials Network (CoVPN) developed and validated a 27-color intracellular cytokine staining (ICS) flow cytometry assay to characterize antigen-specific T-cell responses to both SARS-CoV-2 natural infection and vaccine candidates. Five assay parameters were validated for Th1 and Th2 response: specificity, LOD/LLOQ, precision, linearity, and accuracy. Following submission to the FDA and several rounds of revisions, the assay received FDA approval. This achievement demonstrates the feasibility of a rigorous validation of a functional cellular assay and would not have been possible without quality-controlled instruments. While this staining panel was developed and validated in the context of COVID-19, the approach described here can be applied to other novel functional flow cytometric assays used to assess HIV, tuberculosis, and malaria in the context of infection and vaccination.

Learning Objectives

1. Flow cytometer characterization and standardization

2. Assay optimization for sensitive detection of key functional markers

3. Approach to functional flow cytometric assay validation for clinical trials.

Who Should Attend

Those interested in learning how to optimize and standardize BD flow cytometers. Personnel interested in flow cytometric assay validation for functional markers. 

CMLE Credit: 1.0