| Popis: |
Apoptosis of virally infected cells is a host defense mechanism designed to arrest viral replication by eliminating infected cells (O’Brien 1998). Apoptosis induced by virus infection can be triggered intrinsically by initiating an apoptotic pathway in response to the metabolic changes caused by the infection. The cytotoxic effector cells of the immune system can induce apoptosis in virally infected target cells via multiple mechanisms such as ligation of cell surface death receptors (Wallach et al. 1999), or the release of proteases (granzymes) on contact with target cells (Smyth et al. 2001). A number of viruses evolved with elaborate, often several, strategies to prevent or delay apoptotic host responses (O’Brien 1998; Tschopp et al. 1998). In this article I will review the current status of our knowledge on the cell-death suppressing strategies employed by cytomegaloviruses, a subset of 3-herpesviruses. |
