Scenario description
In this scenario cells co-express two genes simultaneously, enabling identification of the target of interest along with the cell type that expresses that target of interest or the co-expression of two particular targets (Figures 15–18).
Figure 15. Co-expression of PD-L1 (green) and TGFβ1 (red) in lung tumor cells using the RNAscope™ 2.5 HD Duplex assay.
Figure 16. Co-expression of the NRG1 ligand (brown) and the ERBB3 receptor tyrosine kinase (red) in esophageal tumor cells using the RNAscope ® 2.5 LS Duplex assay.
Analysis guidelines
To determine the target co-expression, one can qualitatively assess the degree of simultaneous co-expression of the target with the cell type marker or both targets of interest or perform image-based quantitative software analysis to obtain this information. Hereto, methodologies #1, #2 and #3 can be applied. To determine co-expression across markers and positivity in specific cell populations, these methodologies can be combined to calculate percentage of cells positive. Cells can be scored visually at 40x based on number of cells with >1 dot/cell across the entire tissue section. Percent dual positive is defined as number of cells positive for both Target 1 and Target 2 / total number of cells (see Table 4).
