Accurate prediction and prognosis as well as patient stratification for precision therapy are the most important and difficult issues in cancer treatment. To address these issues, clinical samples derived from patients are typically analyzed using immunohistochemistry (IHC) for specific biomarkers, which play a key role in risk and treatment response assessment. The heterogeneous nature of tumors (e.g. different biological subtypes, different stages of disease progression and different immune response markers) makes identifying different biomarkers difficult. IHC and multiplexing provides researchers working with any tumor type multiple relevant biomarkers and detailed spatial profiling for a more in-depth understanding of their tumor.
For instance, in myeloid-inflamed tumors, CD8+ T cell exhaustion status with low Ki67 and granzyme B are linked to shortened survival. On the contrary, activated CD8+ T cell status correlates with high PD-L1 expression in myeloid cells and is associated with favorable prognosis. This highlights the importance of understanding both total immune complexity and phenotype originating from lymphoid and myeloid lineages.
In the case of metastatic melanoma, different categories of tumor immune control can be present, including PD-L1+ macrophages and PD-L1+ melanoma, PD-L1+ macrophages and PD-L1− melanoma, PD-L1− macrophages and PD-L1− melanoma, or immune exclusion from the tumor. Different categories associate with different responses to the immune checkpoint blockage inhibitors. Therefore, multiplexed tumor immune profiling would be necessary to interpret therapy responses.
In addition to tumor study, other prominent disease studies can similarly benefit from multiplexing analysis. For example, in Alzheimer’s disease studies, the interplay between amyloid plaques and the local immune response plays an important role in moderating disease progression. Specifically, Aβ42 immunoreactive amyloid plaques with or without activated HLA-DR+ microglia and/or reactive GFAP+ astrocytes provides information about the age of amyloid plaque and the degree of inflammation. Multiplexing the above markers with the appropriate synapse degeneration markers (e.g. Neurogranin and axonal degeneration markers such as T-tau) would provide an assessment of disease related damage.
At Visikol, we recently launched our own fluorescent multiplex approach which allows our scientists to examine many biomarkers with clinical value simultaneously on a single formalin-fixed paraffin-embedded (FFPE) tissue section. This provides extensive information regarding colocalization, correlation and spatial relation between various biomarkers. More importantly, these data points enable high dimensional image processing to generate spatial profiles of a patient-level disease microenvironment. This can ultimately provide more accurate prediction, prognosis and drug treatment.
If you are interested in multiplexing biomarkers, please reach out to our team to discuss your project. We are always interested to work together with our Clients to develop customized assays to best suit their needs.