Cancer spheroids and tumoroids are versatile, three-dimensional (3D) in vitro models generated from cancer cells and tumor tissues. Because these 3D cancer models more closely resemble complex tumor biology and cellular interactions observed in vivo, scientists are using them to evaluate candidate immune cell products and accelerate preclinical drug development for urgently needed cellular immunotherapies in solid tumor applications. The simple and sensitive assays of the Maestro Z accurately measure tumor growth and immune cell killing of 3D cancer spheroid models.
The Challenge of Solid Tumors
Heterogeneity
- Tumor heterogeneity can lead to acquired resistance through antigen escape.
Immunosuppression
- The tumor microenvironment (TME) can develop mechanisms to evade or suppress the immune response
- Tumor expression of PD-L1 can trigger the inhibitory PD-1 pathway
- Common immune-suppressive cytokines found in TME: IL-10, TGFB, IL-4, and IL35
Infiltration
- The composition and structure of tumors can prevent t-cell trafficking into the tumor.
Cancer Spheroid Assays
-
Live-cell imaging to measure spheroid killing with fluorescence>
-
Label-free impedance measures growth and immune cell killing in vitro>
-
Investigate immunotherapy potency on models that better reflect solid tumor biology>
-
Application Note: CAR-T Cell Potency Assessment with 3D Cancer Spheroid Models>
-
Assay Steps>
The Omni live-cell imaging platform combines detailed timelapse imaging and AI-driven analysis to track dynamic in vitro tumor killing from the incubator.
Purpose: To measure CAR T cell-mediated killing of cancer spheroids expressing different levels of HER2 antigen using live-cell imaging. Antigen receptor levels have been shown to influence CAR T cytolytic activity.
CAR T cells targeting HER2 antigen were added to spheroids derived from different cancer cell lines expressing GFP. Fluorescent live-cell imaging and quantification was performed by the Omni platform.
Result: CAR T cell-mediated killing was observed against both target cell lines and across different effector-to-target ratios as measured by GFP fluorescent intensity. The rates of cytolysis were directly proportional to the target antigen expression in each line.
