Inhalable Nanofitin demonstrates high neutralization of SARS-CoV-2 virus via direct application in respiratory tract.

Nanofitins are small and hyperthermostable alternative protein scaffolds that display physicochemical properties making them suitable for the development of topical therapeutics, notably for the treatment of pulmonary infectious diseases. Local administration of biologics to the lungs involves a particularly stressful step of nebulization that is poorly tolerated by most antibodies, which limits their application by this delivery route. During the COVID-19 pandemic, we generated anti-SARS-CoV-2 monomeric Nanofitins of high specificity for the spike protein.

Use of the Nanofitin Alternative Scaffold as a GFP-Ready Fusion Tag.

With the continuous diversification of recombinant DNA technologies, the possibilities for new tailor-made protein engineering have extended on an on-going basis. Among these strategies, the use of the green fluorescent protein (GFP) as a fusion domain has been widely adopted for cellular imaging and protein localization. Following the lead of the direct head-to-tail fusion of GFP, we proposed to provide additional features to recombinant proteins by genetic fusion of artificially derived binders.