KLRA1P and infection: To determine whether Ly49 interactions with MHC-I molecules are relevant to influenza infection in vivo, WT (B6) mice were treated two days prior to FM-MA infection, at the day of infection, and every two days after until day 10 p.i. with 200 μg of 5E6 F(ab')2 mAbs, previously reported to block Ly49C/I:H-2Kb interactions [39].