Send to

Choose Destination
Immunity. 2000 Sep;13(3):365-74.

Inhibition of natural killer cell-mediated cytotoxicity by Kaposi's sarcoma-associated herpesvirus K5 protein.

Author information

Tumor Virology Division, New England Regional Primate Research Center, Harvard Medical School, Southborough, Massachusetts 01772, USA.


Kaposi's sarcoma-associated herpesvirus (KSHV) K3 and K5 proteins dramatically downregulate MHC class I molecules. However, although MHC class I downregulation may protect KSHV-infected cells from cytotoxic T lymphocyte recognition, these cells become potential targets for natural killer (NK) cell-mediated lysis. We now show that K5 also downregulates ICAM-1 and B7-2, which are ligands for NK cell-mediated cytotoxicity receptors. As a consequence, K5 expression drastically inhibits NK cell-mediated cytotoxicity. Conversely, de novo expression of B7-2 and ICAM-1 resensitizes the K5-expressing cells to NK cell-mediated cytotoxicity. This is a novel viral immune evasion strategy where KSHV K5 achieves immune avoidance by downregulation of cellular ligands for NK cell-mediated cytotoxicity receptors.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center