Synthesis, Characterization, and Applications of a Superior Dendrimer-Based Polymer for Multiplexed Ion Beam Imaging Time-of-Flight Analysis

Biomacromolecules. 2023 Jul 10;24(7):3105-3114. doi: 10.1021/acs.biomac.3c00174. Epub 2023 Jun 23.

Abstract

High-dimensional single-cell mass spectrometric imaging techniques such as multiplexed ion beam imaging by time-of-flight mass spectrometry (MIBI-TOF), imaging mass cytometry (IMC), and flow cytometry-based CyTOF utilize antibodies conjugated to linear metal-chelating polymers. Here, we report on the synthesis and characterization of a dendrimer-based polymer and its utilization in tissue imaging using MIBI-TOF. We compared the staining performance in FFPE tissue of antibodies for lineage-specific immune proteins (CD20, CD3, CD45, FoxP3) that were conjugated with dendrimer or linear polymer. Staining of serial tissue sections with dendron-conjugated and linear-polymer-conjugated antibodies revealed comparable avidities of dendrons and linear polymers with log2 (ratio of mean positive pixel intensity of staining for linear polymers to dendrons) within the range ±0.25. Interestingly, dendron-conjugated antibodies were observed to have some advantages over linear polymer-conjugated antibodies. For example, tissue staining of a nuclear protein, FoxP3 with dendron-conjugated antibodies showed notably less background staining than that of linear-polymer-conjugated antibodies. Additionally, dendron-conjugated antibodies did not exhibit off-target cytosolic binding in neural tissue typically observed when using linear polymer conjugates. Taken together, this work provides a versatile framework for using third-generation dendron-conjugated antibodies with improved staining over conventional linear polymers.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anthracenes
  • Antibodies / chemistry
  • Dendrimers*
  • Forkhead Transcription Factors
  • Polymers* / chemistry

Substances

  • Polymers
  • dendron
  • Dendrimers
  • Anthracenes
  • Antibodies
  • Forkhead Transcription Factors