To establish a persistent infection, viruses evade many aspe…

To establish a persistent infection, viruses evade many aspects of innate and adaptive immunity. Examples of viral immune evasion strategies are described below. For each strategy, please state whether virally-infected cells (i.e. the ‘target cell’) would be killed by: i) virus-specific CTLs and/or ii) NK cells, and explain why target cell killing by these lymphocytes would or would not occur, for these responses do not consider ADCC reactions. Write 1-2 sentences each part, using the format below (you just need to write A, B, and C and i and ii. A) HIV often harbors mutations in the sole viral epitope presented by MHC class I, resulting in loss of viral peptide binding to the MHC I. i) Virus-specific CTLs: ii) NK cells:  B) Human cytomegalovirus (HCMV) encodes a protein called US3 that binds to MHC Class I molecules and retains them in the ER, so that they are never presented on the cell surface. i) Virus-specific CTLs:  ii) NK cells: C) Poxviruses encode a protein called crmA, which can inhibit caspases 3 and 8. i) Virus-specific CTLs:  ii) NK cells: