MKI67 and COVID-19: Ki67+ proliferating epithelial cells were increased in COVID-19 patients compared to control patients (32.3 ± 5.5 vs. 18.1 ± 9.6 cells per 100 EC, p < 0.01), while the proliferation of lamina propria cells was comparable in COVID-19 patients and controls (1.2 ± 0.6 cells vs. 0.7 ± 1.3 cells per 100 LP cells).