When filtering for antimicrobial response and lung as a target organ to get a more complete and specific comparison between the healthy state and COVID-19 pneumonia, many of the identified transcripts were downregulated in the network and are important for the defense against viral infections and antibody production (such as ADAR, CAMP, IFNB1, IRF5, LTF, SFTPD, TLR4, TLR7, TLR9, IL10 and CD40) which indicates an inhibition of the innate immune system by the virus. The gene discussed is TLR9; the disease is viral infectious disease.