Effect of heparinase enzyme on Zebrafish (ZF) encoded 3-<i>O</i>ST-4 mediated cell to cell fusion with HSV-1 glycoprotein expressing cells (A–C).

<p><b>A.</b> ZF 3-<i>O</i>ST-4-expressing target CHO-K1 cells gain the ability to fuse with effector cells co-expressing HSV-1 glycoproteins gB, gD, gH, and gL while heparinase treatment significantly blocks ZF 3-<i>O</i>ST-4 mediated fusion. The target CHO-K1 cells were transfected with plasmids expressing ZF 3-<i>O</i>ST-4 and luciferase reporter gene. The effector CHO-K1 cells were transfected with HSV-1 glycoproteins gB, gD, gH, and gL, and T7 RNA polymerase. CHO-K1 effector cells expressing control plasmid without HSV-1 glycoproteins were used as a negative control. In addition, target CHO-K1 cells expressing ZF 3-<i>O</i>ST-4 were treated with heparinase II/III (1.5 U/ml) (blur bar) or left untreated (red bar) for 1 hr prior to co-cultivation with effector CHO-K1 cells expressing four HSV-1 essential glycoproteins (gB, gD, gH-gL; 0.5 µg DNA each glycoprotein). A luciferase reporter assay was performed 24 h after the two cell populations were mixed together. Cell fusion was measured in relative luciferase units (RLUs) using a Sirius luminometer (Berthold Detection System). Similarly visual observation resulted multinucleated giant cells (<b>panel B</b>; subpanels a and b) with CHO-K1 cells expressing ZF 3-<i>O</i>ST-4 mixed with effector cells expressing HSV-1 glycoproteins. However hepainase treatment to ZF 3-<i>O</i>ST-4 cells resulted significant decrease in giant cell formation. <b>Panel c</b> represent cartoon indicating cell fusion in mock treated ZF 3-<i>O</i>ST-4 cells (subpanel a) vs. heparinase treated ZF 3-<i>O</i>ST-4 cells inhibiting HSV-1 glycoprotein mediated cell fusion (subpanel b).