Biomimetic nanoplasmonic sensor for rapid evaluation of neutralizing SARS-CoV-2 monoclonal antibodies as antiviral therapy
Razia Batool, Maria Soler, Francesca Colavita, Lavinia Fabeni, Giulia Matusali, Laura M. Lechuga
Abstract
Monoclonal antibody (mAb) therapy is one of the most promising immunotherapies that have shown the potential to prevent or neutralize the effects of COVID-19 in patients at very early stages, with a few formulations recently approved by the European and American medicine agencies. However, a main bottleneck for their general implementation resides in the time-consuming, laborious, and highly-specialized techniques employed for the manufacturing and assessing of these therapies, excessively increasing their prices and delaying their administration to the patients. We propose a biomimetic nanoplasmonic biosensor as a novel analytical technique for the screening and evaluation of COVID-19 mAb therapies in a simpler, faster, and reliable manner. By creating an artificial cell membrane on the plasmonic sensor surface, our label-free sensing approach enables real-time monitoring of virus-cell interactions as well as direct analysis of antibody blocking effects in only 15 min assay time. We have achieved detection limits in the 102 TCID50/mL range for the study of SARS-CoV-2 viruses, which allows to perform neutralization assays by only employing a low-volume sample with common viral loads. We have demonstrated the accuracy of the biosensor for the evaluation of two different neutralizing antibodies targeting both Delta and Omicron variants of SARS-CoV-2, with half maximal inhibitory concentrations (IC50) determined in the ng/mL range. Our user-friendly and reliable technology could be employed in biomedical and pharmaceutical laboratories to accelerate, cheapen, and simplify the development of effective immunotherapies for COVID-19 and other serious infectious diseases or cancer.