Multiplexed molecular imaging with surface enhanced resonance Raman scattering nanoprobes reveals immunotherapy response in mice via multichannel image segmentation

Abstract

Visualizing the presence and distribution of multiple specific molecular markers within a tumor can reveal the composition of its microenvironment, inform diagnosis, stratify patients, and guide treatment. Raman imaging with...

Multiplexing potential of NIR resonant and non-resonant Raman reporters for bio-imaging applications

“…42 Such overlap provides an additional gain of SERRS and improves the absolute Raman signal intensities of the contrast agent. 6,29,43 However, on the other hand, after efficiently absorbing light at 785 nm, the NIR dyes can also emit light, which might explain the presence of extra-background for SERRS NPs spectra as compared to SERS NPs, as shown in Fig. 2.…”

“…24 No doubt, more NIR dyes can be synthesized for screening if they can serve as more sensitive reporters for Raman imaging. 29,48,49 But NIR dyes will still have complex spectral barcodes crowded in the fingerprint region, with interference of fluorescence background, and thus a significant degree of overlap for the main Raman bands.…”

“…Currently, there is little information regarding the benefits of using non-resonant Raman reporter molecules over those of resonant Raman reporters, or vice versa for multiplexing purposes. Although both have been reported to be sensitive and capable of multiplexing in vivo 8,11,23,29 and ex vivo, 12,13 there is yet to be a direct comparative study exploring their respective multiplexing potential, side by side, in a controlled setting. Herein, we focus on determining the multiplexing capabilities of five non-resonant Raman reporters and five NIR-resonant heptamethine cyanine dyes that have routinely been used for biomedical imaging 2,8,11,13,23,29 with the intention to increase plexity (number of flavors) for accurate and robust spectral unmixing.…”

“…Although both have been reported to be sensitive and capable of multiplexing in vivo 8,11,23,29 and ex vivo, 12,13 there is yet to be a direct comparative study exploring their respective multiplexing potential, side by side, in a controlled setting. Herein, we focus on determining the multiplexing capabilities of five non-resonant Raman reporters and five NIR-resonant heptamethine cyanine dyes that have routinely been used for biomedical imaging 2,8,11,13,23,29 with the intention to increase plexity (number of flavors) for accurate and robust spectral unmixing. Both types of Raman reporters were studied on gold nanospheres with a silica coating.…”

A Systematic Approach toward Enabling Maximal Targeting Efficiency of Cell Surface Proteins with Actively Targeted SERS Nanoparticles

“…After pioneering applications of SERS NPs for molecular imaging were introduced in vivo by Gambhir’s group, , several research teams focused their efforts toward (1) developing new Raman imaging tools; (2) unraveling the multiplexing potential of SERS NPs; ,− (3) increasing their sensitivity down to sub-fM limits of detection (LODs); (4) increasing penetration depth of Raman imaging; − (5) improving speed of Raman imaging in conjunction with SERS NPs; (6) optimizing spectral unmixing algorithms; and (7) adding multiple imaging modalities. − Furthermore, SERS NPs have demonstrated their potential in detection of various important biomarkers such as carbonic anhydrase IX (CA9), cluster of differentiation 24 (CD24), CD44, , CD47, ,, epidermal growth factor receptor (EGFR), − ,,− epithelial cellular adhesion molecule (EpCAM), estrogen receptor (ER), human epididymis protein 4 (HE4), human epidermal growth factor receptor 2 (HER2), − ,, programmed death-ligand 1 (PD-L1), , and progesterone receptor (PR) . However, most studies have not comprehensively analyzed the distinctive attributes of the SERS NPs for achieving a high biotargeting specificity.…”