PMID- 33631930 OWN - NLM STAT- MEDLINE VI - 32 IP - 4 TI - Highly Multiplexed Immunohistochemical MALDI-MS Imaging of Biomarkers in Tissues. PG - 977-988 LA - eng PT - Journal Article PL - United States TA - J Am Soc Mass Spectrom JT - Journal of the American Society for Mass Spectrometry JID - 9010412 IS - 1879-1123 (Electronic) LID - 10.1021/jasms.0c00473 [doi] FAU - Yagnik, Gargey AU - Yagnik G AUID- ORCID: http://orcid.org/0000-0002-3197-3089 AD - AmberGen, Inc., 313 Pleasant Street, Watertown, Massachusetts 02472, United States. FAU - Liu, Ziying AU - Liu Z AD - AmberGen, Inc., 313 Pleasant Street, Watertown, Massachusetts 02472, United States. FAU - Rothschild, Kenneth J AU - Rothschild KJ AD - AmberGen, Inc., 313 Pleasant Street, Watertown, Massachusetts 02472, United States. AD - Molecular Biophysics Laboratory, Department of Physics and Photonics Center, Boston University, Boston, Massachusetts 02215, United States. FAU - Lim, Mark J AU - Lim MJ AD - AmberGen, Inc., 313 Pleasant Street, Watertown, Massachusetts 02472, United States. IS - 1044-0305 (Linking) RN - 0 (Biomarkers) RN - 0 (Biomarkers, Tumor) RN - 0 (Peptides) RN - 9013-20-1 (Streptavidin) SB - IM MH - Animals MH - Biomarkers/*analysis MH - Biomarkers, Tumor/analysis MH - Brain Chemistry MH - Breast Neoplasms/chemistry MH - Female MH - Fluorescent Antibody Technique MH - Humans MH - Immunohistochemistry/*methods MH - In Situ Hybridization MH - Mice MH - Microspheres MH - Palatine Tonsil/chemistry MH - Peptides/chemistry/radiation effects MH - Photochemistry MH - Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/*methods MH - Streptavidin MH - Ultraviolet Rays OTO - NOTNLM OT - bead-arrays OT - immunofluorescence OT - immunohistochemistry OT - in situ hybridization OT - mass spectrometric imaging OT - mass spectrometry OT - mass-tags OT - matrix-assisted laser desorption/ionization OT - multiplexing OT - pathology OT - photocleavable OT - tissue diagnostics PMC - PMC8033562 DCOM- 20211122 LR - 20211122 DP - 2021 Apr 07 DEP - 20210225 AB - Immunohistochemistry (IHC) combined with fluorescence microscopy provides an important and widely used tool for researchers and pathologists to image multiple biomarkers in tissue specimens. However, multiplex IHC using standard fluorescence microscopy is generally limited to 3-5 different biomarkers, with hyperspectral or multispectral methods limited to 8. We report the development of a new technology based on novel photocleavable mass-tags (PC-MTs) for facile antibody labeling, which enables highly multiplexed IHC based on MALDI mass spectrometric imaging (MALDI-IHC). This approach significantly exceeds the multiplexity of both fluorescence- and previous cleavable mass-tag-based methods. Up to 12-plex MALDI-IHC was demonstrated on mouse brain, human tonsil, and breast cancer tissues specimens, reflecting the known molecular composition, anatomy, and pathology of the targeted biomarkers. Novel dual-labeled fluorescent PC-MT antibodies and label-free small-molecule mass spectrometric imaging greatly extend the capability of this new approach. MALDI-IHC shows promise for use in the fields of tissue pathology, tissue diagnostics, therapeutics, and precision medicine.