Skip to main content
. 2017 Jan 3;91(2):e01859-16. doi: 10.1128/JVI.01859-16

FIG 6.

FIG 6

scFv PL-2 blocks GFP-Spike2 binding to Caco-2 cells. (A) Superdex 200 10/300 size exclusion chromatography traces of indicated GFP and GFP fusion proteins. (B) ELISA results showing binding of scFv PL-2 to GFP-Spike2 but not GFP, GFP-GST, GFP-Spike1, or GFP-Spike8. (C) Schematic of the Caco-2 cell binding assay showing GFP-Spike dimer attachment to the cell surface. (D) Cell binding assay showing the percentage of fluorescent Caco-2 cells after incubation with indicated proteins. Note abbreviations for GFP-Spike 1 (GFP-SP1), GFP-Spike2 (GFP-SP2), and GFP-Spike8 (GFP-SP8). Samples containing scFv PL-2 are indicated with a plus sign (+) below protein names. Experiments were performed in biological duplicates. Unpaired t test for GFP with GFP-Spike2 and for GFP-Spike2 with GFP-Spike2 + scFv confirms significant differences. (E) Coomassie blue-stained SDS-PAGE of protein samples used for the cell binding assay. Samples containing a 4 M excess scFv PL-2 (band at ∼30 kDa) are indicated. (F) Overlay of histogram plots of Caco-2 cells incubated with PBS, GFP, GFP-GST, GFP-Spike1, GFP-Spike2, and GFP-Spike8. (G) Stacked histogram plots of Caco-2 cells incubated with GFP-fused proteins alone or with scFv PL-2. All histogram plots show fluorescence intensity versus relative cell count.