Description
Applications
CAR-T Cell-Mediated Cytotoxicity
Ramos (HT-HiBiT) Bioassays are amenable to use in HiBiT TCK Bioassays using CAR-T effector cells. Ramos Cells (HT-HiBiT) were incubated with serially diluted CD19 human CAR-T cells at the indicated E:T ratios. After a 4-, 24-, 48- or 72-hour induction, Bio-Glo-NB™ TCK Reagent was added.
Antibody-Dependent Cell-Mediated Cytotoxicity (ADCC)
HiBiT TCK Bioassays reflect the ADCC MoA of biologic drugs and demonstrate specificity for cell surface antigens. Ramos Cells (HT-HiBiT) were incubated with Human PBMC, ADCC-qualified effector cells in the presence of serial titrations of antibodies, including Control Ab, Anti-CD20 (Cat.# GA1130), as indicated. After a 5-hour induction, Bio-Glo-NB™ TCK Reagent was added.
T Cell-Dependent Cell-Mediated Cytotoxicity (TDCC)
HiBiT TCK Bioassays reflect the TDCC MoA of biologic drugs and demonstrate specificity for cell surface antigens. Ramos Cells (HT-HiBiT) were incubated with human T Cells (CD8+) in the presence of bispecific T cell engagers (BiTE®). After a 24-hour induction, Bio-Glo-NB™ TCK Reagent was added.
Antibody-Dependent Cellular Phagocytosis (ADCP)
Ramos (HiBiT) TCK Bioassays reflect the ADCP MoA of biologic drugs. Ramos Cells (HiBiT) were incubated with Human Macrophages (ADCP-qualified) in the presence of serial titrations of rituximab. After a 24-hour induction, Bio-Glo-NB™ Lytic Reagent was added. Loss of signal reflects HiBiT degradation following phagocytosis of the Ramos target cell.
After substrate was added, luminescence was quantified using the GloMax® Discover System. Data were fitted to a four-parameter logistic curve using GraphPad Prism software. HT = HaloTag, the fusion partner for the HiBiT tag.
Data sourced from the Human Protein Atlas transcriptomic data of human cell lines. Version 23.0, updated on 23-06-19 [ The Human Protein Atlas ].
When Ramos (HT-HiBiT) target cells are cocultured with appropriate effector cells (e.g., CAR-T cells, PBMCs or cytotoxic T cells) they can be specifically used to monitor the activity of biologics directed against receptors expressed on the Ramos Cells (HT-HiBiT), such as CD19, CD20 or CD38. When Ramos Cells (HT-HiBiT) are used in assays with biologics against TAAs they do not express, target cells are not lysed and no increase in luminescent signal is observed. Representative data for different MoA are above.
