ITSN2 and infection: To gain insights into which cellular processes underlying the humoral immune response were impaired in Itsn2-/- mice, we infected WT and Itsn2-/- animals with a sub-lethal dose of 104 PFU Vaccinia virus (Western reserve) via intra-footpad injection and analysed the popliteal lymph nodes by flow cytometry 7 days after infection.