The phosphoproteome has become a point of interest for researchers due to its implications across many critical fields of study, including cancer immunology and infectious disease. Because the phosphorylated proteins that make up the phosphoproteome coordinate and direct intracellular signaling, they can be thought of as the electrical wiring of the cell. Gaining a better understanding of how individual cells are “wired” can help to uncover pathways involved in cancer cell growth, response to therapy, or even the development of resistance to treatments. However, specific changes to, or the rewiring of, pathways may be missed in bulk analyses or techniques limiting the number of proteins being measured. To fully understand changes in pathways or pathway activation, coordinated signals from within the same cell must be captured simultaneously. In doing so, researchers can identify early biomarkers of disease and new therapeutic targets.
IsoPlexis’ Single-Cell Signaling solution uniquely measures the cellular signaling driving phosphorylation events and signal coordination. The analyzed proteins are connected back to each individual cell, revealing the electrical wiring driving cells to unlock the next level of resolution in advanced medicine and immune research. Unlike traditional technologies which can only measure a few analytes at a time, the Single-Cell Signaling solution enables the analysis of 15+ analytes simultaneously, with lysing on-chip and without any tedious additional steps.
Single-Cell Signaling Detects Pathway Activation in Rare Cells
Glioblastoma (GBM) is the most common and aggressive primary malignancy of the brain. Current treatments, which include surgical resection followed by simultaneous radiotherapy and chemotherapy, are often ineffective—with less than 5% of patients surviving past five years from diagnosis.
In a study published in Cancer Cell, researchers performed single-cell phosphoproteomics on a patient-derived in vivo GBM model of mTOR kinase inhibitor (mTORki) resistance and followed up these findings with analytics to identify changes in signaling coordination.
In this study, Western Blot was unable to predict treatable intracellular resistance signatures, as bulk analysis is an average of all cell data. Conversely, the mTOR, ERK, and SRC pathways were detected by IsoPlexis’ platform in rare single cells throughout signal coordination. The signaling coordination uncovered by detecting simultaneous phosphoproteomic reactions from individual cells provided treatment targets, leading to longer-term survival.
Single-Cell Signaling Characterizes Signaling Coordination Driving Resistance
In a study published in Nature Communications, researchers used IsoPlexis’ Single-Cell Signaling platform to analyze mutant melanoma cancer cells (BRAFV600E M397) treated with BRAF inhibitor (BRAFi) over five days. IsoPlexis’ platform characterized the phosphoproteins of single cells and measured oncogenic signaling coordination. Using IsoPlexis’ single-cell signaling platform, the researchers identified two different cell populations within the overall group of cells, which took different paths to drug resistance. Using this information, the researchers were able to identify drug susceptibilities of both pathways, and ultimately found that by increasing the dosage of BRAFi, one of these subpopulations was eliminated. The study stated that the critical information uncovered with IsoPlexis’ platform “update[s] the current understanding of resistance development and can provide a powerful methodology for identifying therapy combinations,” enabling researchers to develop potential combination therapies to combat drug-resistant cell states.
IsoPlexis Addresses Challenges and Limitations of Traditional Methods to Reveal Cell Wiring
Traditional methods, such as phosphoflow and western blot, inundated with overly complicated workflows and tedious protocols, do not provide cooordinated insights into the entire signaling network. In order to find the right biomarker or target while simultaneously understanding coordinated signaling pathways, the phosphoproteome must be studied and measured at the single-cell level. IsoPlexis’ Single-Cell Signaling Platform, which measures signaling coordination via 15+ proteins per cell in 500-1500 individual cells in parallel, can uniquely measure how cells are wired, revealing critical cell signaling pathways to accelerate advanced cancer therapeutics.