Extended Data Fig. 7. Expression of LGAL3BP in the human cerebral parenchyma and in human IPSC derived astrocytes.
(a) Representative maximum intensity projection of a human cerebral cortex section showing the absence of immunostaining when the primary antibodies against GFAP and LGALS3BP (MDP1959) were omitted from the primary staining step in immunodetection protocol (n = 4 patient samples). (b) Immunostaining for GFAP and MDP1959 (detecting LGALS3BP) showing a sparse labelling in the intact cerebral parenchyma (b′) and in the gliotic region (b′′) distal to the hemorrhagic brain lesion. Boxed areas in b′ and b′′ are shown at higher magnification. Circles indicate the areas of MDP1959 immunostaining (n = 4 patients). Maximum intensity (c) and orthogonal projection (c’) images showing the examples of LGALS3BP immunolabelling (dashed circles) in the gliotic regions and few LGALS3BP+GFAP+ cells (white arrowheads) (n = 3 patients). GFAP+LGALS3BP+ reactive astrocytes in regions of moderate (d) and severe gliosis (e) are indicated by white arrowheads (n = 4 patients). (f) Single optical plane images showing representative examples of LGALS3BP+ hiAstros (white arrowheads) cultured under control condition (f′) or in the presence of CSF-CCM (f′′). Histogram depicting the percentage of LGALS3BP+ hiAstros in the control and CSF-CCM containing cell culture medium (g). Data are shown as median with interquartile range. Each dot represents one biological replicate (n = 3 per biological replicate). Dot color indicates iPSC line: #1 (empty), HMGU12 (grey), UKERi82a-R1-002 (black). Two-tailed P-value from unpaired t-test with Welch’s correction. Scale bars: 50 µm (a, b), 30 µm (c), 20 µm (d, e), 15 µm (f).