NIST Flow Cytometry Standards Consortium 

Advances in cell and gene-based therapeutics as well as other regenerative medicine products have increased the need for high quality, robust, and validated measurements for cell characterization. Flow cytometry, including imaging cytometry, has emerged as an important platform due to its ability to rapidly and simultaneously characterize heterogeneous cell populations and subcellular analytes. For example, flow cytometry has been critical for establishing identity, purity, and potency for Chimeric Antigen Receptor (CAR)-T cell manufacturing; and associated data to support the approval of Biological License Applications (BLA) by the U.S. Food and Drug Administration (FDA) and the approval by the European Medicines Agency (EMA). In addition, multiparameter flow cytometric measurements are routinely carried out in vaccine, drug and cancer research, clinical diagnosis, and immunotherapies. However, challenges remain with respect to measurement confidence and comparability of measurement results from different instrument platforms, locations, and over time, hindering critical decision-making based on flow cytometry data in research and clinical settings. The NIST Flow Cytometry Standards Consortium aims to bring together experts across the regenerative medicine field including stakeholders in industry, academia, and government to address this need.   

CONSORTIUM GOALS  

• Develop reference standards including reference materials, reference data, reference methods, and measurement service for assigning the Equivalent Number of Reference Fluorophores (ERF) to calibration microspheres and assessing the associated uncertainties and utilities  
• Develop candidate reference standards including biological reference materials, reference data, reference methods 
• Design interlaboratory studies based on candidate reference materials to support the development of best practices and standard methods  

CONSORTIUM ORGANIZATION   

• In coordination with the Consortium steering committee, Working Groups will be established to meet the Consortium goals  

CONSORTIUM IMPACT  

• Shared measurement assurance tools and standards for flow cytometry measurement confidence 
• Data from interlaboratory studies to support development of best practices and standard methods   
• Improved flow cytometry measurement capabilities  

CONSORTIUM MODEL  

• Convenes industry, academia, and government to identify and address measurement and standards needs across the flow cytometry application field
• Enables members to work with NIST to develop measurement solutions and standards  
• Leverages NIST expertise in measurement science, standards development, reference materials, technology development, and basic research  
• Collaborates with related programs at other organizations 

WHY NIST 

• Cross-disciplinary expertise in engineering and the physical, information, chemical, and biological sciences  
• As a non-regulatory agency of the U.S. Department of Commerce, NIST does not impose standards; standards are accepted by consensus  
• Neutral convener for industry consortia, standards development organizations, federal laboratories, universities, public workshops, and interlaboratory comparability testing
   

Four working groups (WG) have been formed under the consortium to drive the development of standards, measurement assurance tools, best practices and methods, and advanced capabilities.

• WG1: Develop reference standards including reference materials, reference data, reference methods, and measurement service for assigning the Equivalent Number of Reference Fluorophores (ERF) to calibration microspheres and assessing the associated uncertainties and utilities, and drive cytometer standardization
  • The first interlaboratory study on ‘Cross calibration with ERF bead sets and ERF assignment to unknowns’ – Data submission near completion
• WG2: Design and conduct interlaboratory studies for the development of reference standards, control materials, and best practice protocols to achieve assay standardization and reference data generation  
  • The first interlaboratory study on ‘Standardization of a TBMNK assay on cell count and health’ – Data submission near completion
• WG3: Build infrastructure and capability for flow cytometry data repository and standardized reporting and multi-modal simultaneous data analysis
  • Data repository infrastructure with NASA’s Jet Propulsion Laboratory, California Institute of Technology near completion
• WG4: Developing measurement solutions and standards for gene delivery systems to improve measurement confidence by establishing traceability and assisting measurement comparability ​ 
  • Planning first interlaboratory study to include measurements of capsid titer, genomic titer, particle concentration, and orthogonal measurements

RELATED PUBLICATIONS

• Measurement Solutions and Standards for Advanced Therapy
• Standardization of Flow Cyotmetric Detection of the Antigen Expression
• Establishing CD19 B-cell Reference Control Materials for Comparable and Quantitative Cytometric Expression Analysis
• An Accurate and Rapid Single Step Protocol for Enumeration of Cytokine Positive T Lymphocytes
• Measurement and Standardization Challenges for Exosome-Based Delivery Vectors
• Expanding NIST's Calibration of Fluorescent Microspheres for Flow Cytometry to More Fluorescence Channels and Smaller Particles
• Workshop 13: Building Measurement Assurance in Flow Cytometry
• Comparison of Volumetric and Bead-Based Counting of CD34 Cells by Single-Platform Flow Cytometry
• Number Concentration Measurements of Polystyrene Submicrometer Particles