Figure 1From: Plaque assay for human coronavirus NL63 using human colon carcinoma cellsCytopathogenic effect of hCoV-NL63 on human colon carcinoma cells (CaCo-2). CaCo-2 cells 5 days after infection with hCoV-NL63 at an multiplicity of infection of 0.1 (agarose overlay technique). A, mock-infection; B, infection. Photographs were taken at 40-fold magnification; bars represent 20 μm.Back to article page