Related Experiment Video
Updated: Sep 13, 2025

09:19
Spatial Profiling of Protein and RNA Expression in Tissue: An Approach to Fine-Tune Virtual Microdissection
Published on: July 6, 2022
5.0K
A New Tool to Decrease Interobserver Variability in Biomarker Annotation in Solid Tumor Tissue for Spatial
Sravya Palavalasa1,2, Emily Baker1, Jack Freeman1
1Department of Radiation Oncology, University of Michigan, Ann Arbor, MI 48109, USA.
Current Issues in Molecular Biology
|July 29, 2025
Summary
Manual annotation of DNA damage markers in spatial transcriptomics is variable. A new MATLAB tool enables reproducible spot-wise image analysis, improving gene expression association studies in irradiated glioblastoma.
Area of Science:
- Oncology
- Genomics
- Bioinformatics
Background:
- Spatial transcriptomics and immunofluorescence have different resolutions, complicating data integration.
- Accurate identification of DNA damage regions is crucial for understanding cellular responses in irradiated tissues.
- Manual annotation of immunofluorescence data in spatial transcriptomics exhibits significant interobserver variability.
Purpose of the Study:
- To develop a reproducible method for integrating spatial transcriptomics and immunofluorescence data.
- To overcome interobserver variability in annotating DNA damage markers like γH2AX in spatial transcriptomic spots.
- To enable accurate comparison of gene expression between DNA-damaged and undamaged regions.
Main Methods:
- Coupling spatial transcriptomics of irradiated glioblastoma with immunofluorescence for γH2AX.
- Developing a MATLAB tool for spot-wise image analysis and annotation based on intensity thresholds and cell counts.
- Comparing gene expression profiles in γH2AX-positive and negative regions.
Main Results:
- Significant interobserver variability (Kappa = 0.345) was observed in manual annotation of γH2AX positivity.
- The developed MATLAB tool achieved reproducible annotation of spots, even in regions with high manual variability.
- The tool facilitated consistent identification of genes associated with DNA repair pathways.
Conclusions:
- A novel MATLAB tool significantly improves the reproducibility of integrating spatial transcriptomics and immunofluorescence data.
- This tool addresses the challenge of interobserver variability in manual annotation, leading to more reliable downstream analyses.
- The developed method enhances the study of DNA damage responses and associated gene expression in glioblastoma.

