IFNG and pneumonia: However, recent studies evaluating cells from bronchopulmonary lavage (BAL) of patients infected with SARS-CoV2 vs other organisms using single cell RNA-seq to define the different cell populations and what they expressed observed that in severe SARS-CoV2 pneumonia there was a high number of T cells thought to be recruited by infected macrophages expressing cytokines and chemokines such as CCL4 and CXCL10 that in turn expressed proinflammatory cytokines such as interferon-gamma (IFNγ) that further stimulated the inflammatory macrophages [18, 19].