(a-g) t-SNE visualization of cell types present in the
wild-type mouse aortic root from all timepoints combined (n=9 mice).
(a) Cell types are indicated for each cluster.
(b–f) t-SNE visualization at all timepoints combined,
overlaid with expression of Tagln, Cnn1, Lgals3, Fn1 and
Tnfrsf11b. Expression levels are indicated by scales in the lower
left of each panel. n=9 mice. (g) A SMC modulation score was
calculated for each cell based upon the expression of top differentially
expressed genes between modulated SMC and contractile SMC clusters. Blue
indicates more similarity to contractile SMC, red indicates more similarity to
phenotypically modulated SMC. (h) Tagln expression
in quiescent and modulated SMCs at 0, 8 and 16 weeks of high-fat diet (HFD). All
expression levels are normalized for library size and log-transformed.
(i) Transcriptional shift from contractile SMC to
phenotypically modulated SMC phenotype at 16 weeks HFD, from the viewpoint of
each non-SMC cell type within the lesion. Bars to the right of center indicate
that, relative to contractile SMCs, modulated SMCs have shifted toward a given
cell type. Bars to the left indicate that they have shifted away. Color
represents the magnitude of shift (blue = farther away, red = closer towards).
(j) Top enriched pathways for gene expression changes seen with
SMC phenotypic modulation, as performed with Ingenuity Pathway Analysis (IPA).
The top 200 differentially-expressed genes were analyzed with Fisher’s
exact test (right-sided). Blue bars indicate negative Z-scores of predicted
activation, and grey bars indicate that the pathway had not yet been annotated
by IPA to yield an activity pattern. (k) t-SNE visualization at all
timepoints combined, overlaid with expression of Lum. n=9 mice.
(l-n) RNAscope staining in the mouse aortic root at 8 weeks of
high-fat diet. Yellow arrows highlight cells at the fibrous cap expressing both
Lum (green, in l) and tdT
(red, in m), with merged Lum and
tdT staining shown in (n). Dapi staining is
shown in blue. Images in (l-n) are representative of 3 experiments,
and scale bars represent 50μm. (o) t-SNE visualization at
all timepoints combined, overlaid with expression of Cd68. n=9
mice. (p) tdT expression (red) and Cd68 immunostaining (white).
Dapi staining is shown in blue. (q) tdT expression (red) and BODIPY
lipid stain (green). Co-localization of tdT and BODIPY is highlighted with
yellow arrows. (r) BODIPY lipid stain (green) and Cd68
immunostaining (white). Co-localization of BODIPY and Cd68 is highlighted with
yellow arrows. Lu = lumen, M = media. Images in (p-r) are
representative of 3 experiments, and scale bars represent 50μm.