**2.4 Study of the immune response against the EBV using EBV BACs**

There are three recombinant wild-type EBVs that have been generated so far (Delecluse, Hilsendegen et al. 1998; Kanda, Yajima et al. 2004; Chen, Divisconte et al. 2005). They were generated by the insertion of the prokaryotic F-plasmid (F-factor) in two B95.8 or one Akata strains. Although the insertion sites differ in these three EBV BACs, at the site of the B95.8 deletion (Delecluse, Hilsendegen et al. 1998), or at the major internal repeat region of the B95.5 strain (Chen, Divisconte et al. 2005), or at BXLF1 open reading frame (ORF) in Akata strain (Kanda, Yajima et al. 2004), the insertion site of the F-plasmid does not affect the phenotype of the virus.
