Skip to main content
. 2021 Feb 8;40(6):e105123. doi: 10.15252/embj.2020105123

Figure 8. Disease stage‐dependent gene expression pattern in myeloid cells during experimental CNV.

Figure 8

  1. Trajectory analysis reveals alterations in gene expression pattern over time and disease state (d0, d3, d7). Above: Trajectory heatmap depicting loss of homeostatic microglial gene expression signatures (P2ry12, Tmem119, Csf1r, SiglecH) and induction of genes involved in cytoskeleton modifications (Actb, Tuba1c), cell cycle progression (Cdk1, Ptma), and antigen presentation (Cd74, H2‐Aa). Highlighted molecules (asterisks) were confirmed by immunohistochemistry shown in (B–D). Below: Trajectory plot showing the trajectory followed by myeloid cells upon CNV progress.
  2. Above: P2ry12 expression is shown by trajectory analysis and represented in a t‐SNE plot. Expression is high in homeostatic microglia (see Figs 1G and H and 7H). Below: Typical immunohistochemistry for P2RY12 (green) in unlesioned and lesioned areas. Arrows indicate lost P2RY12 expression. Asterisks mark microglial cells that maintained P2RY12 expression. Iba1 immunohistochemistry (red) to show microglia. Pictures are representative of two mice. Scale bars represent 25 µm.
  3. Above: Tmem119 expression visualized by trajectory analysis and represented in a t‐SNE plot. High signals in homeostatic microglia (see Fig 1G and H). Below: TMEM119 immunofluorescence (green) by Iba1+ (red) microglia inside lesioned and non‐lesioned areas in the retina and RPE. Arrows indicate microglia with lost TMEM119 expression whereas asterisks mark microglial cells that maintained TMEM119 expression. Picture is representative of two mice. Scale bars represent 25 µm.
  4. Above: Ptma expression presented by a t‐SNE plot and its trajectory analysis over the disease course. Ptma expression correlates with proliferation of rMGs at d7 during CNV in Cx3cr1CreERT2:Rosa26‐tdTomato mice. Below: Representative immunofluorescence of proliferating EdU+ (white) Iba1+ (red, Tomato) microglia at sites of CNV on d7 (arrow) next to an EdU−Tomato+Iba1− cell (asterisks) after EdU treatment from d0 to d6. Arrowhead points toward an intravascular myeloid EdU−Tomato−Iba1+ cell. Typical pictures from three mice obtained from one independent experiment are shown. Scale bar represents 25 µm.