Transitioning from native to recombinant proteins for IVD kit development

The selection of primary raw materials, whether antigens, proteins, or antibodies, plays a pivotal role in determining the performance of any new immunoassay. Historically, first-generation immunoassays have often relied on native proteins, which have proven effective in achieving the performance standards required for in-vitro diagnostic (IVD) applications.

However, the use of native proteins and antigens is not without challenges. These materials are inherently subject to significant lot-to-lot variability, which can impact assay consistency and reproducibility. In addition, their production is frequently costly, time-intensive, and operationally complex.

Our Approach

At Werfen, we are actively working to make our immunoassay solutions more efficient and scalable. As part of this effort, our R&D Biotechnology team is developing a new monoclonal antibody to replace polyclonal antibodies currently obtained from human sera.

The target antigen presents several technical difficulties that make standard development approaches insufficient:

• High structural complexity and a short, constrained epitope.
• Very low amino acid differences between antigen variants, requiring exceptional selectivity.
• High sequence identity with conventional immunization hosts, limiting the natural immune response

Our team has structured the development around five core stages:

1. Antigen Generation: Comprising target analysis, computational construct design, and functional evaluation to engineer a suitable immunogen.
2. Antigen Purification: Ensuring a well-defined, high-quality starting material for immunization.
3. Immunization: Using tailored strategies adapted to the specificities of this target.
4. Antibody Purification: Isolating and enriching the best candidates from the immune response.
5. Antibody Characterization: Evaluating candidates across structural, physicochemical, and functional parameters to confirm assay suitability.

Outcomes

A recombinant antigen displaying the epitope of interest has been successfully generated and is recognized by human antibodies against the selected epitope. This antigen will now serve as the basis for monoclonal antibody generation, with the objective of potentially replacing the polyclonal antibody currently used in an existing IVD assay