Evaluation of MDSC-mediated Regulation of Anti-tumor Immunity
The Serametrix MDSC Assay is a 4-color assay that measures the frequency of myeloid-derived suppressor cells (MDSCs) in whole blood. The MDSC assay uses flow cytometry to provide an unrivalled view of the cellular immune response to cancer, measuring these important peripheral immune cells. Data analysis with our proprietary algorithm supports correct interpretation of data. Studies measure both mMDSC and gMDSC using this published, clinically relevant assay. Ideal for patient stratification or patient selection, the Serametrix MDSC Assay is available for exploratory research or clinical CLIA studies.
MDSC Assay Components
The Serametrix MDSC Assay includes study design, MDSC assay, and results with comprehensive analysis and interpretation.
MDSCs inhibit T-cell proliferation and permit continued tumor growth. Their abundance is associated with poor prognoses, and elevated levels of MDSCs can render cancer patients less able to derive clinical benefit from immunotherapies. Study examples are listed below.
Monitoring M-MDSC Depletion Following Checkpoint Combo
Bristol Myers Squibb (BMS) clinical study NCT01024231 was an anti-CTLA-4/anti-PD-1 combination study (ipi/nivo) for hepatocellular carcinoma (HCC). The results showed that conventional biomarkers failed to predict outcome (notably PD-L1 status). Low pre-treatment M-MDSC predicted increased clinical response and on-treatment decreases in M-MDSC were more common in the combo cohort. The conclusion was that combination therapy can reduce MDSC and increase PD-1 effectiveness (1).
Monitoring Response to ipilimumab
In another study of 26 patients receiving immunotherapy it was found that patients with relatively low levels of MDSCs at baseline were more likely to respond well to immunotherapy. Furthermore, it was observed that non-responders not only had elevated MDSC at baseline but more frequently had an upward trend during immunotherapy treatment (2).
Monitoring G-MDSC Depletion Following MDSC Inhibitor
In Rgenix, Inc. clinical study NCT01024231, RGX-104 (LXR agonist) with anti-MDSC evidence in mice. Results demonstrated first evidence for RGX-104 effect on MDSC in cancer patients, proving the effectiveness of the Serametrix G-MDSC assay (3).
(1) Callahan et al. (2013). Peripheral blood and tumor biomarkers in patients with advanced melanoma treated with combination nivolumab (anti-PD-1, BMS-936558, ONO-4538) and ipilimumab. J Immunother Cancer. 2013; 1(Suppl 1): O6.
(2) Postow et al. (2014) Peripheral and tumor immune correlates in patients with advanced melanoma treated with nivolumab (anti-PD-1, BMS-936558, ONO-4538) monotherapy or in combination with ipilimumab. Journal of Translational Medicine, 12(Suppl 1).
(3) Tavazoie et al., (2018) LXR/ApoE Activation Restricts Innate Immune Suppression in Cancer. Cell 172, 1–16.