HHV-8 K14

Human herpesvirus 8 (HHV-8) belongs to the Gammaherpesviridae family of herpesviruses and has been etiologically linked to three distinct neoplasms: Kaposi's sarcoma, multicentric Castleman's disease, and a primary effusion lymphoma. Genome sequencing of HHV-8 revealed that it carried an ORF, K14, which was homologous to CD200 yet had only 40% sequence identity. K14 protein, despite the low sequence similarity to CD200, has perfectly retained its biochemical binding properties for the CD200 receptor in order to directly mimic CD200 function and thereby deliver a localized down-regulatory signal to host myeloid cells.