Efforts to develop vaccine and immunotherapeutic countermeasures against the COVID-19 pandemic focus on targeting the trimeric spike (S) proteins of SARS-CoV-2. Vaccines and therapeutic design strategies must impart the characteristics of virion S from historical and emerging variants onto practical constructs such as soluble. stabilized trimers. The virus spike is a heterotrimer of t... https://www.chiggate.com/3m-speedglas-9002nc-welding-helmet-fashion/