Figure 3

Flow cytometric quality and in-process control of IFN-γ-based CliniMACS CCS enrichment of CMV-specific T cells. IFN-γ⁺ CMV-specific T cells were isolated from leukapheresis by large-scale GMP-grade CliniMACS CCS- and small-scale MiniMACS CSA-based process. Flow cytometric analysis was performed with all CliniMACS CCS and MiniMACS CSA fractions (leukapheresis, original fraction (OF), T-cell fraction (TCF), negative fraction (NF), waste fraction (WF), 48 h, 54 h, and 72 h post-leukapheresis (Stabi48, Stabi54, and Stabi72)) by using the quality control panel (QCP) -A, QCP-B and QCP-C-. The results of the representative analysis of the leukapheresis and TCF by using the QCP-A panel are shown (n = 3). As a control the QCP-A⁻ was used as fluorescence minus one (FMO) for IFN-γ. Dot plots show the qualitative analysis of IFN-γ-secreting CMV-specific T cells [%]. CD3⁺IFN-γ⁺ percentages were defined on viable CD3⁺ T cells, and CD8⁺IFN-γ⁺ and CD4⁺IFN-γ⁺ percentages were defined on viable CD4⁺ and viable CD8⁺ T-cells, respectively. IFN-γ⁻secreting T cells are shown in the gate represented on each dot plot.