Nano-DSF Technology as a Preliminary Decision-Making Tool for Long Term Stability Evaluation of Covid-19 Vaccine Antigens.

PURPOSE: Nano differential scanning fluorimetry (nano-DSF) is a high-throughput screening technique that simultaneously assesses colloidal and conformational stabilities of protein antigens by monitoring their thermal unfolding patterns and aggregation behaviors. It offers significant advantages over conventional approaches used for thermal stability assessment of proteins, such as Differential Scanning Calorimetry (DSC).

METHODS

The present study evaluates the thermal unfolding and aggregation behavior of an in-house recombinant COVID-19 SARS-CoV-2 spike protein variant and its engineered prototype as vaccine antigens. We investigated their structural integrity and colloidal behavior under well-defined physical conditions such as pH transition, addition of excipients, and at different manufacturing stages.

RESULTS

Changes in melting and aggregation temperatures (Tm and Tagg) were assessed as indicators of the structural integrity and colloidal stability of spike protein variants.

CONCLUSION

We have shown how nano-DSF technology can be useful in developing a stable formulation which can minimize conformational changes and aggregation. Our study highlights the potential of nano-DSF for process optimization and as an advanced preliminary decision-making tool to be used before initiating long-term stability studies in biopharmaceutical R&D.