ADCP Assay Services

Antibody-dependent cell-mediated phagocytosis (ADCP) is an important mechanism of action (MOA) of therapeutic antibodies. In vivo, ADCP can be mediated by monocytes, macrophages, neutrophils and dendritic cells through FcγRIIa, FcγRI and FcγRIIIa. In terms of mechanism, antibodies bind their homologous antigens to target cells through their antigen recognition domains, and then recruit phagocytes to targets with their Fc regions. Once bound to the Fc receptors of phagocytes, the target cells are taken up and degraded. This process also causes the effector cells to produce soluble factors, which help initiate and drive the immune response. ADCP function is very important in the development of therapeutic antibodies, especially for biosimilars.

Creative Biolabs has extensive experience with ADCP assays and can help you understand the interaction between your compound or biologic and the phagocytic cells of the immune system, taking you to clinic faster. We conduct ADCP bioassays on behalf of clients, either as a standalone project or as part of a larger development project. We are committed to developing the most appropriate experiments to help you understand the molecule.

The ADCP Assay Principle

ADCP can be mediated by FcγRIIa, FcγRI and FcγRIIIa by monocytes, macrophages, neutrophils and dendritic cells. Although all three receptors can participate in ADCP, it is believed that FcγRIIa is the main Fcγ receptor involved in this process.

In our ADCP analysis, the FcγRIIa-H ADCP reporter bioassay is a biologically relevant MOA-based assay that can be used to measure the potency and stability of antibodies and other biological agents that specifically bind and activate FcγRIIa. The assay consists of Jurkat cells stably expressing human FcγRIIa-H (high affinity H131 variant) and NFAT-induced luciferase. The activation of FcγR and NFAT-mediated luciferase activity in effector cells was measured by flow cytometry. Phagocytosis can also be confirmed using microscopy or imaging cytometry.

Fig.1 Cell-based ADCP assays used to assess the FcγR-mediated effector functions.^{1, 3}

ADCP Assay Performance Data

Accuracy and precision are critical to the development of bioassays and novel biological agents. Our ADCP Reporter bioassay is both accurate and precise, and has been prequalified in accordance with ICH guidelines, and shows the precision, accuracy and linearity required for routine use in potency and stability studies. We work closely with you to choose the most suitable method based on the immune cells or diseases of interest.

Fig.2 Increasing concentrations of rituximab were incubated with Raji target cells and NFAT-RE effector cells either with or without FcγRIIa-H expression.

Fig.2 Antibodies induce ADCP responses within lymphoma cell lines.^{2, 4}

For more detailed information, please feel free to contact us or directly sent us an inquiry.

References

1. Gogesch, Patricia, et al. "The role of Fc receptors on the effectiveness of therapeutic monoclonal antibodies." International Journal of Molecular Sciences 22.16 (2021): 8947.
2. Geanes, Eric S., et al. "Development of combinatorial antibody therapies for diffuse large B cell lymphoma." Frontiers in Medicine 9 (2022): 1034594.
3. under Open Access License CC BY 4.0. The original image was modified by extracting and using a part, and the title was changed to “Cell-based ADCP assays used to assess the FcγR-mediated effector functions”.
4. under Open Access License CC BY 4.0. The original image was modified by extracting and using a part, and the title was changed to “Antibodies induce ADCP responses within lymphoma cell lines”.