Immune evasion activity

Myxomatosis is associated with general immunosuppression of the host and thus MV was a prime candidate to encode immune evasion molecules. Initial work identified the MV M-T7 gene encoding a 37 kDa glycoprotein that is abundantly secreted from infected cells. The M-T7 ORF showed significant similarity to the extracellular binding domain of human and mouse interferon-y receptors (IFN-yRs), and was shown to bind to and inhibit the biological activity of rabbit IFN-y in a species specific manner. ... 

The discovery of vCKBPs in the poxviruses raised an important question is the production of a secreted vCKBP an immune evasion strategy unique to the poxviruses, or is it also exploited by other mammalian viruses The herpesviruses are an obvious virus family in which to search for novel activities since they, like the poxviruses, have large DNA genomes encoding numerous genes involved in immune evasion. 

Pfander R, Neumann L, Zweckstetter M, Seger C, Holak TA, Tampe R (1999) Structure of the active domain of the herpes simplex virus protein ICP47 in water/sodium dodecyl sulfate solution determined by nuclear magnetic resonance spectroscopy. Biochemistry 38 13692 13698 Ploegh HL (1998) Viral strategies of immune evasion. Science 280 248- 253... 

From what is known about CMV-encoded chemokines and chemokine receptors, it appears that their participation in immune evasion would be mainly at the level of viral dissemination sheltered from the immune system through (cell-to-cell) passage and movement of receptor bearing infected cells bidirectionally across endothelial barriers. In addition, the ability of pUS28 to withdraw CC chemokines from the environment of infected cells could also confer a measure of immune evasion by blunting effector lymphocyte migration and activation. 

Neipel F, Albrecht J-C, Fleckenstein B (1997) Cell-homologous genes in the Kaposi s sarcoma-associated rhadinovirus human herpesvirus 8 determinants of its pathogenicity. J Virol 71 4187 192 Perng GC, Jones C, Ciacci-Zanella J, Stone M, Henderson G, Yukht A, Slanina SM, Hofman FM, Ghiasi H, Nesburn AB, Wechsler SL (2000) Virus-induced neuronal apoptosis blocked by the herpes simplex virus latency-associated transcript. Science 287 1500-1503 Raftery MJ, Behrens CK, Muller A, Krammer PH, Walczak H, Schonrich G (1999) Herpes simplex virus type 1 infection of activated cytotoxic T cells Induction of fratricide as a mechanism of viral immune evasion. J Exp Med 190 1103 1114... 

By the time they have reached the lungs, schistosomula are innately resistant to immune effector mechanisms that are capable of killing schistosomula newly transformed from cer-cariae. In part, this is a reflection of the fact that growing schistosomula develop the ability to avoid activating complement and to evade recognition by antibodies (see below), and therefore are no longer susceptible to antibody or complement-mediated cellular cytotoxicity. However, studies in which these evasion mechanisms have been experimentally bypassed have revealed underlying resistance to immune effector molecules (Moser et al., 1980) the basis of this resistance is unknown. 

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