Czech Society for Mass Spectrometry

(Czech Mass Spectrometry Conference 2023 - MoP-12)
Single particle inductively coupled plasma mass spectrometry imaging of immunochemically labeled spheroid sections

Vilém Svojanovský ¹, Jan Preisler ^1 *, Marek Stiborek ¹, Viktor Kanický ¹, Jiří Kroupa ²

1. Masarykova Univerzita
2. VUT Brno

Abstract

Spheroids are one of the 3D biological models in which the arrangement of proliferating and necrotic cells resembles the tumor microenvironment. One of the markers of proliferation is Ki-67 protein, which is expressed by cells in the active phase of the cell cycle. Immunohistochemical labeling with a primary antibody and a fluorophore-labeled secondary antibody followed by fluorescence microscopy analysis is commonly employed for two- and three-dimensional imaging of the target protein in spheroid sections. We have successfully switched from fluorophore labeling of Ki-67 to nanoparticle labeling combined with LA ICP MS. Recently, gold nanoparticles were used as very sensitive immunochemical tags in conventional UV laser ablation ICP MSI.[1,2] In our approach, intact ​20 nm gold nanoparticles tags were desorbed from the spheroid section with 2940 nm laser ablation system.[3]

* Corresponding author: svojanovsk@gmail.com

References

1. Cruz-Alonso, María, et al., Microchimica Acta 185 (2018): 1-9
2. Tvrdonova, Michaela, et al., Analytical and bioanalytical chemistry 411 (2019): 559-564
3. Stiborek, Marek, et al., Analytical Chemistry (2022)

Acknowledgement:

The authors gratefully acknowledge the financial support of the Czech Science Foundation (21-12262S), Masaryk University, Brno, Czech Republic (MUNI/A/1325/2021), European Regional Development Fund - Project ENOCH (CZ.02.1.01/0.0/16_019/0000868), the project National Institute for Cancer Research (Programme EXCELES, ID Project No. LX22NPO5102) - funded by the European Union - Next Generation EU, and MEYS CR infrastructure project LM2018127 of CIISB.