HERPES-SIMPLEX-VIRUS BLOCKS INTRACELLULAR-TRANSPORT OF HLA-G IN PLACENTALLY DERIVED HUMAN-CELLS

Spontaneous fetal loss is associated with herpes simplex virus (HSV) i nfection as deduced from epidemiologic data, To date, the underlying m echanisms remain to be elucidated, but an immune component is suspecte d. HLA-C is a class I MHC molecule selectively expressed on extravillo us cytotrophoblast; this cell type does not express conventional HLA-A or -B, whereas expression of novel HLA-C-like products has been repor ted, While its function remains unclear, a role for HLA-G in silencing NK cells that would otherwise attack cells devoid of classical class I molecules has been invoked, We here show that expression of HLA clas s I molecules is abrogated in HSV-infected choriocarcinoma cells, a ph enomenon mediated by the virally encoded inhibitor of the transporter associated with Ag presentation, ICP47, These observations may provide a link between HSV infection and spontaneous fetal loss.