Enzymatic removal of cell surface heparan sulfate (HS) by heparinase treatment in ZF 3-<i>O</i>ST-4 expressing CHO-K1 cells reduces HSV-1 infection.

<p>Three groups of cultured CHO-K1 cells expressing empty vector pcDNA3.1 or ZF 3-<i>O</i>ST-4 or human 3-<i>O</i>ST-3 were treated with heparinase II/III (1.5 U/ml; grey bar) or mock treated (black bar) followed by exposing cells to HSV-1 (KOS) gL86 at 20 PFU/cell and viral entry was quantitated 6 hr later by ONPG assay (<b>panel A</b>) and fluorescent microscopy and quantification (panel B, and panel C). In the latter case HSV-1 capsid-tagged to RFP (HSV-1K26RFP) virus was used. The heparinase treated ZF-3-<i>O</i>ST-4 and human 3-<i>O</i>ST-3 cells had significantly lesser number of viral entry (<b>panel A</b>) compared to mock treated ZF-3-<i>O</i>ST-4 or 3-<i>O</i>ST-3 cells. Similarly confocal visualization (<b>panel B</b>) and quantification (<b>panel C</b>) resulted less red punctate of HSV-1K26RFP on heparinase treated ZF 3-<i>O</i>ST-4 or human 3-<i>O</i>ST-3 cells compared to mock treated cells.