%0 Journal Article %T Herpes Simplex Virus Type-1 (HSV-1) Entry into Human Mesenchymal Stem Cells Is Heavily Dependent on Heparan Sulfate %A Samiksha Choudhary %A Maribel Marquez %A Frances Alencastro %A Frank Spors %A Yuanxiang Zhao %A Vaibhav Tiwari %J Journal of Biomedicine and Biotechnology %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/264350 %X Hematopoietic stem cells recipients remain susceptible to opportunistic viral infections including herpes simplex virus type-1 (HSV-1). The purpose of this investigation was to analyze susceptibility of human mesenchymal stem cells (hMSCs) to HSV-1 infection and identify the major entry receptor. Productive virus infection in hMSCs was confirmed by replication and plaque formation assays using a syncytial HSV-1 KOS (804) virus. To examine the significance of entry receptors, RT-PCR and antibody-blocking assays were performed. RT-PCR data showed the expression of gD receptors: nectin-1, 3-O sulfotransferase-3 (3-OST-3), and HVEM. Antibody-blocking assay together with heparinase treatment suggested an important role for HS and 3-O-sulfated heparan sulfate (3-OS HS), but not nectin-1 or HVEM, in mediating HSV-1 entry and spread in hMSCs. Taken together, our results provide strong evidence demonstrating that HSV-1 is capable of infecting hMSCs and HS and 3-OS HS serve as its entry receptors during this process. %U http://www.hindawi.com/journals/biomed/2011/264350/