H5N1 i.m. immnization has fairly good amount of antibodies but they don't neutralize influenza virus whereas antibodies by i.n. route do neutralize influenza virus.
Jasmine, it is quite likely to detect antibodies in an ELISA that do not subsequently neutralize your vius. Neutralizing antibodies are a small subset of the total antibody raised against a given virus
Absolutely! However, these antibodies may have functional activity in an ADCC assay. You will likely have to "challenge" the mice to determine if they are protected or not, as the in vitro mVN may not accurately predict protection in vivo.