Introducing Our Cutting-Edge ELISA Method
Bispecific antibodies are a groundbreaking class of molecules that have revolutionized targeted therapies. These unique antibodies are designed to simultaneously bind two different targets. Some bispecific constructs consist only of Fab pieces, or Fv pieces, the ~25,000 Da complete antigen binding site of one Light chain. These smaller “nanobodies” are a challenge for an ELISA technique. An example is blinatumomab or BlincytoTM that links CD3 bearing human host killer T cells with CD19 bearing B cell malignances leading to their death, see the figure below.
Key challenges in developing an ELISA for bispecific antibody constructs are listed below, including related to being more sensitive to degradation and lower affinity due to having a scFv region rather than a Fab2 dimer property or a complete two-antigen binding arms of an IgG molecule.
| Bispecific antibody properties | Challenge |
|---|---|
| Confirmation of Bispecific Antibodies | Validating the bispecific nature and functionality of both antigen-binding domains |
| Conformational Changes | Overcoming induced conformational changes upon binding targets |
| Differential Binding Affinities | Quantifying across concentrations when each target has varying affinities |
| Detection Assay Design | Developing specific assays without cross-reactivity with other antibody formats |
| Analytical Sensitivity | Detecting low levels of bispecific antibodies for accurate PK/PD analysis |
| Sample Matrix Interference | Overcoming the interference from complex biological matrices that impact assay sensitivity and reliability. |
Key features and benefits of our ELISA method
The principle of the MarinBio bispecific ELISA is shown in the figure below.
The sensitivity of MarinBio’s ELISA surpasses that other bispecific antibodies.
The reported sensitivity of the ELISA for various bispecific antibodies is shown in the Table below.
| Bispecific Antibody | ELISA Sensitivity |
|---|---|
| CD3 x BCMA (B cell maturation antigen) | 4ng/mL (1) |
| CTLA-4 (cluster of differentiation 152, CD152) x OX40 (tumor necrosis factor receptor superfamily, member 4,TNFRSF4), ATOR-1015 | 4ng/mL(2) |
| Blinatumomab, BlincytoTM, anti cD3 x anti cD19 | 50 -100ng/mL (3) |
The sensitivity of the MarinBio’s bispecific antibody ELISA MarinBio is 0.016ng/mL in buffer and 0.06ng/mL in neat serum.
Results of the MarinBio bispecific Fab ELISA.
Key features of the MarinBio’s bispecific Fab ELISA
Specificity: The ELISA assay is designed to specifically detect both target proteins of the bispecific construct, ensuring accurate and reliable results without interference from other antibody formats.
Sensitivity: The method has a lower limit of quantitation of 0.060ng/mL while using only 17µL serum per well.
Versatility: MarinBio’s ELISA method can be applied to various bispecific antibody formats.,
Flexibility: The assay can be customized to accommodate specific study objectives, whether it is pharmacokinetics/pharmacodynamics (PK/PD) analysis, preclinical toxicology studies, or clinical trials.
GMP/GLP ELISA: MarinBio has validated this bispecific antibody ELISA and can adapt the technology to detect other bispecific antibodies in GLP or cGMP assays.
Conclusion: The development of a novel bispecific antibody ELISA method marks a significant leap forward in the analysis and characterization of bispecific nanobodies.
Marin Biologic Laboratories is proud to offer this innovative service, supporting researchers, pharmaceutical / biotech companies, in their quest to develop and optimize bispecific antibody-based treatments.
Hyperlinks:
3.https://www.sciencedirect.com/science/article/pii/S0006497120452073?via%3Dihub
