Extended Data Fig. 9: Presence and persistence of CAR-T cells in CSF of patient and cytokine profiling in peripheral blood plasma versus CSF after development of neurotoxicity.
(a) Representative plots showing the gating strategy on CSF to get to the T cell gate. (b) Flow cytometric data of cerebrospinal fluid from day 148 after CAR-T cell infusion, showing presence of CD4 + and CD8 + CAR-T cells. (c) Flow cytometric data of cerebrospinal fluid from day 155 after CAR-T cell infusion (that is after administration of intravenous cyclophosphamide and intrathecal cytarabine), showing persistent presence of CD4 + and CD8 + CAR-T cells. (d) Normalized protein expression (NPX) log2 values of all cytokines in the Olink Immuno-Oncology panel, in serum (top) and CSF (bottom) (high protein levels in red, low protein levels in blue). (e) Scatter plot showing overall correlation of cytokine levels in plasma versus CSF (Pearson correlation coefficient r = 0.70, two-sided p < 0.001). (f) The log2 fold change (FC) of CSF versus blood plasma in a healthy control (along x-axis) and the patient who developed neurotoxicity (along y-axis). Highlighted are a selection of cytokines that are overrepresented in the patient’s CSF compared to the healthy control data. Among the cytokines that are overrepresented, we note a set of cytokines suggesting T cell activation (for example GZMB, GZMA, IFN-γ, CD40L, CD8A, CD27, FASLG), cytokines that are induced by IFN-γ (for example CXCL5, CXCL10, CXCL11) and that are known to act as chemo-attractants for T cells (among other immune cell types), and cytokines that point to possible involvement of cells in the blood-brain barrier (BBB) (for example PDGFB, EGF and ANGPT1).
