Fig. 3

Spatiotemporal change of the bacterial spectral signature in the tumor environment and the muscle. A 4T1 (a) and a CT26.WT (b) tumor-bearing mouse intratumorally injected with Rba. capsulatus SB1003 is shown together with the hind leg muscle with the same injection (c). Shown are representative reconstructed images overlaid by unmixed pixels in false colors. Color coded regions indicate a mixture of 800 nm/860 nm peaks or predominance of the 860-nm peak as visualized in d. Shown are mean spectra of all regions of the same color. Unmixed pixels are shown as black if automatic peak assignment failed. Strong signal (white) in the reconstructed images at 720 nm relates to high absorption by blood or other absorber that has not been identified by the unmixing procedure. Data for all mice at all timepoints can be found in Supplementary Figure 14 (a n = 3, b n = 3, c n = 2). The analyzed region of interest (i.e., tumor) is indicated as a dotted line. All scale bars, 1 mm