| Abstract [eng] |
During the study, the interaction between covalently immobilized SARS-CoV-2-oS protein and polyclonal antibodies present in blood sera obtained from individuals who had recovered from COVID-19 and those vaccinated with the Comirnaty vaccine was investigated. After selecting suitable conditions for the covalent immobilization of the SARS-CoV-2-oS protein, real time total internal reflection ellipsometry method was employed to determine changes in ellipsometric parameters upon interaction of polyclonal antibodies with the SARS-CoV-2-oS protein. Mathematical models were applied for the evaluation of interactions: an optical model was used to calculate the surface mass density, and a two-step model was utilized to calculate kinetic parameters and thermodynamics. It was found that after interaction of the SARS-CoV-2-oS protein with polyclonal antibodies present in blood serum obtained from an individual vaccinated with the Comirnaty vaccine, a higher surface mass density was formed. The association rate of these antibodies is higher than that of polyclonal antibodies present in blood serum obtained from an individual who had recovered from COVID-19, however, the dissociation rate is lower. Additionally, polyclonal antibodies present in blood serum obtained from an individual who had recovered from COVID-19 exhibit a 14-fold higher affinity to the SARS-CoV-2-oS protein and thermodynamically favour the formation of an immune complex. |
