A new publication using Attana Technology from National University of Singapore examining the neutralization capacity of human IgG antibodies agsinst different mutations of the SARS-CoV-2
During the pandemic it has been observed that individuals react very differently to be infected by the virus and to the vaccination. A few individuals obtain very strong protection against the wild type (the original Wuhan) and the mutated variants, whereas others obtain less good protection. This paper in Nature Communications focus on characterizing the neutralization capacity (protection) of antibodies from convalescent COVID-19 individuals against SARS-CoV-2 virus. Using Attana technology, kinetic characterization of the antibody-spike interaction reveals that the antibodies with the best kinetics properties are the same ones that provides the that the strongest neutralizing capacity. For Attana these results are yet another independent research publication with results that supports our concept of immunity profiles where kinetic interaction properties are used to determine how well protection an individual has to a given pathogen.
The uniqueness of this paper is the combination of many different technologies and that the studies have been performed at experimentally challenging but physiologically more relevant conditions than previously published results. For instance, have the effect of glycosylation of the spike mutations and the importance of the dynamics of the interaction been included. Overall, this resulted in that the antibodies from convalescent individuals could be divided into weak, moderate, and strong neutralizers.
Attana QCM technology has been applied to study the interaction kinetics of the different antibodies. High affinity binding in the sub-nM range with slow dissociation rates were observed. The association-dissociation kinetics clearly indicate stable binding of the antibodies to the Spike trimer. In the neutralization experiments the highest neutralization was observed for the two antibodies CoVA2-39 and 5A6. These two antibodies have the fastest association rate, being 1.25*106mol/s and 1.18*106mol/s respectively.
Association rates in the magnitude of 106mol/s has in several previous studies using Attana technology been observed to correlate with strong neutralization, e.g. for SARS-CoV-2, dengue, hepatis B, tetanus, and tuberculosis. In correlation with the dissociation rate, this is used as criteria’s in Attana’s immunity profiles, where kinetic interaction properties are used to determine how well protection an individual has to a given pathogen. Consequently, this study forms a good reference for the application of Attana technology and kinetic characterization as a mean for determine neutralizing capacity.
Attana QCM kinetic evaluation of the interactions between Spike and SARS CoV-2 antibodies