Performance of spectral flow cytometry and mass cytometry for the study of innate myeloid cell populations.

Introduction: Monitoring of innate myeloid cells (IMC) is broadly applied in basic and translational research, as well as in diagnostic patient care. Due to their immunophenotypic heterogeneity and biological plasticity, analysis of IMC populations typically requires large panels of markers. Currently, two cytometry-based techniques allow for the simultaneous detection of ≥40 markers: spectral flow cytometry (SFC) and mass cytometry (MC). However, little is known about the comparability of SFC and MC in studying IMC populations.
Methods: We evaluated the performance of two SFC and MC panels, which contained 21 common markers, for the identification and subsetting of blood IMC populations. Based on unsupervised clustering analysis, we systematically identified 24 leukocyte populations, including 21 IMC subsets, regardless of the cytometry technique.
Results: Overall, comparable results were observed between the two technologies regarding the relative distribution of these cell populations and the staining resolution of individual markers (Pearson's ρ=0.99 and 0.55, respectively). However, minor differences were observed between the two techniques regarding intra-measurement variability (median coefficient of variation of 42.5% vs. 68.0% in SFC and MC, respectively; p<0.0001) and reproducibility, which were most likely due to the significantly longer acquisition times (median 16 min vs. 159 min) and lower recovery rates (median 53.1% vs. 26.8%) associated with SFC vs. MC.
Discussion: Altogether, our results show a good correlation between SFC and MC for the identification, enumeration and characterization of IMC in blood, based on large panels (>20) of antibody reagents.
Competing Interests: JJMvD and AO are chairmen of the EuroFlow scientific foundation, which receives royalties from licensed patents, which are collectively owned by the participants of the EuroFlow Foundation and are exclusively used for continuation of the EuroFlow collaboration and sustainability of the EuroFlow consortium. JJMvD and AO report an Educational Services Agreement from BD Biosciences San José, CA and a Scientific Advisor Agreement with Cytognos/BD Biosciences; all related fees and honoraria are for the involved university departments at Leiden University Medical Center and University of Salamanca. JJMvD, AO, CT and KvdP are listed as coinventors on the patent “Means and methods for multiparameter cytometry-based leukocyte subsetting” PCT/NL2020/050688, filing date 5 November 2019, owned by the EuroFlow scientific consortium, that formed the basis for part of the antibody combination described in this manuscript. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be considered as a potential conflict of interest.
(Copyright © 2023 van der Pan, Khatri, de Jager, Louis, Kassem, Naber, de Laat, Hameetman, Comans, Orfao, van Dongen, Díez and Teodosio.)