CD40LG and infection: In this study we compared the efficacy of IgM and IgG polyclonal immunoglobulin preparations from plasma of human convalescent COVID-19 cases against SARS-CoV-2 (Wuhan-1) infection and associated pathology in Syrian golden hamsters, a model with a severe disease phenotype that does not require genetic modification of the host or virus to promote viral replication and disease (43, 44).