An imaging approach that allows for the simultaneous visualization of up to 100 clinically relevant metal isotope-labeled antibodies in human breast tumors from tissue sections is reported this week in Nature Medicine. This technique provides important and accurate information about disease pathogenesis that may help with clinical diagnosis.

Immunohistochemistry and immunofluorescence are tools that visualize proteins using colored pigments and fluorescence signals and that have been the cornerstone of clinical diagnostics involving tissue sections. However, technical and practical shortcomings have limited their use. In particular, these methods are not appropriate for quantitatively analyzing multiple antigens expressed in tissues or cells, which is often needed to understand the molecular and morphological features of clinical biopsies.

Garry Nolan and colleagues developed a method called multiplexed ion beam imaging (MIBI) that allows with high sensitivity the analysis of numerous molecular markers at the same time using standard formalin-fixed, paraffin-embedded tumor tissue sections, which are commonly used in the clinic. Using MIBI, the authors imaged breast tumor tissue sections stained with clinically relevant metal-conjugated antibodies to demonstrate that the technique may be useful in a diagnosis setting.

The approach can provide new insights into disease pathogenesis, tumor heterogeneity and pathway activation status at the single-cell level, and aid in the classification of cancer patients, although some limitations still exist regarding its use in the clinic for diagnostic purposes.