Characterization

Definition Characterization refers to the systematic description and analysis of a biological sample, process, or phenomenon to understand its components, structure, function, or behavior. In biomedical research, it often involves identifying the molecular, cellular, genetic, or functional features of tissues, cells, or diseases.

• Tumor characterization: involves assessing histology, molecular markers, gene expression, immune infiltration, and mutation status
• Immune cell characterization: defines cell type, activation state, surface markers, and cytokine profile
• Drug characterization: describes pharmacokinetics, mechanism of action, and off-target effects

• Histological analysis (H&E staining, IHC)
• Flow cytometry and immunofluorescence
• Genomic and transcriptomic profiling (e.g., RNA-seq, WES)
• Functional assays (e.g., cytotoxicity, migration, proliferation)
• Imaging techniques (e.g., MRI, PET, confocal microscopy)

• Enables accurate diagnosis and classification
• Guides treatment decisions and patient stratification
• Supports biomarker discovery and drug development
• Provides insights into mechanisms of disease or response

Characterization of the tumor immune microenvironment may reveal high CD8+ T cell density, PD-L1 expression, and presence of tertiary lymphoid structures—suggesting potential benefit from immunotherapy.