Immunostaining of SARS-CoV-2 in Lung Tissue

Lung tissue sections were fixed in zinc formalin, embedded in paraffin, and then subjected to epitope retrieval using solutions of varying pH (Vector Labs H-3301 and H-3300) as previously described in [26 (link),27 (link)]. Blocking was performed using BSA/or serum, followed by incubation with primary and secondary antibodies. The dilutions and the primary antibodies were 1:1000 anti-SARS (NR-10361, BEI, Manassas, VA, USA), 1:500 anti-Spc (WRAB-9337, Seven Hills Bioreagents, Cincinnati, OH, USA), and 1:20 anti-cytokeratin antibody (Z0622, Dako, Glostrup, Denmark). The corresponding secondary antibodies were added as detailed in [27 (link)]. Digital imaging was executed using a Zeiss Axio scan. Z1. (Jena, Germany).