Whilst we have been unable to identify the IL-27(R)-regulated tissue-derived soluble signals that promotes CD4+ T cell migration to the liver during infection, alternative chemoattractants that may control CD4+ T cell migration include High Mobility Group Box-1 (HMGB-1), a danger associated molecular pattern (DAMP) that induces neutrophil accumulation in the liver during viral infection [18], and which can act directly on T cells [19], [20], and VAP-1, which promotes T cell accumulation during ConA-induced liver inflammation [21]. This evidence concerns the gene CD4 and viral infectious disease.