Flow cytometric method transfer: Recommendations for best practice

Abstract

As with many aspects of the validation and monitoring of flow cytometric methods, the method transfer processes and acceptance criteria described for other technologies are not fully applicable. This is due to the complexity of the highly configurable instrumentation, the complexity of cellular measurands, the lack of qualified reference materials for most assays, and limited specimen stability. There are multiple reasons for initiating a method transfer, multiple regulatory settings, and multiple context of use. All of these factors influence the specific requirements for the method transfer. This recommendation paper describes the considerations and best practices for the transfer of flow cytometric methods and provides individual case studies as examples. In addition, the manuscript emphasizes the importance of appropriately conducting a method transfer on data reliability.

Best practices for the development, analytical validation and clinical implementation of flow cytometric methods for chimeric antigen receptor T cell analyses

“…When assays are transferred from one laboratory to another, whether within the same building or across the globe, method transfer validation should be conducted. Current best practices for transfer of flow cytometric methods are described by (Cabanski et al, 2021; Selliah et al, 2019). In order to minimize the variations between instruments, analysts or testing facilities, it is recommended that the same reagents and same SOPs for all aspects of the laboratory are used.…”

Best practices for optimization and validation of flow cytometry‐based receptor occupancy assays

“…In both cases, assay validation should be conducted in order to fully understand assay suitability and performance (CLSI, 2021; Green et al, 2016). When the assay will be deployed at multiple locations as is common with global clinical trials, an assay transfer validation should also be conducted (Cabanski et al, 2021). Validation parameters for ROA include linearity, precision, and stability, with other assessments added as required (Green et al, 2016; O'Hara et al, 2011; Piccoli & Michael, 2019; Pluim, Ros, Miedema, Beijnen, & Schellens, 2019; Selliah et al, 2019).…”

“…In such cases, a method transfer validation is required in addition the initial analytical method validation. The best practices for method transfer validation are described by Cabanski et al (2021).…”

“…In both cases, assay validation should be conducted in order to fully understand assay suitability and performance (CLSI, 2021;Green et al, 2016). When the assay will be deployed at multiple locations as is common with global clinical trials, an assay transfer validation should also be conducted (Cabanski et al, 2021).…”

Issue Highlights

“…The upcoming Clinical Laboratory and Standards Institute (CLSI) guideline, H62 the Validation of Methods Performed by Flow Cytometry addresses these topics (CLSI, 2021). In addition, this Special Issue of Clinical Cytometry includes four new recommendation papers, generated by the AAPS Flow Cytometry APC, which also address different challenges associated with the validation of cellbased assays(Cabanski et al, 2021;Hilt et al, 2021;Sarikonda et al, 2021a; Sommers et al, 2021).The first step in any method validation should be to determine the COU of the assay and the associated regulatory requirements.While this may seem obvious enough, this step is often overlooked during the development and validation of flow cytometric methods and as a result the final assays fail to meet performance specifications.To improve the likelihood of successful outcomes, a best practice is to implement the Design Control process for risk evaluation and implementation planning. Design Control is a familiar process in regulated settings; however, this concept is likely to be new to many cytometrists.…”