Bystander Effect Assays | Abzena

Bystander Assay

The ability of a drug conjugate to target both antigen-positive cells and neighbouring antigen-negative cells is called a bystander effect. To assess the bystander activity of a drug conjugate, a mixture of antigen-positive and antigen-negative cells are incubated in the presence of compound. After 6 days in culture, the remaining cell population is analysed by flow cytometry. Antigen-positive and antigen-negative viable cells are identified, counted and compared to untreated samples.

Working with Abzena

Abzena’s undertakes bioassays on behalf of clients as standalone projects or as part of larger development projects. We focus on developing the correct bioassay to help you understand your molecule and will help guide you in the correct.

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Trastuzumab-ThioBridge™-MMAE ADC (10 nM) has no anti-proliferative effect on the Her2-negative A549 cell line as a single culture. However, when co-cultured with Her2-positive SK-BR-3 cells, A549 cells are killed and the effect increases with the SK-BR-3:A549 ratio.
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