To test whether Itsn2-/- B cells were also impaired in responding to viral infection, we infected 80–20 chimeras in μMT or 50–50 chimeras in B6.CD45.1 with Vaccinia virus injected intra-footpad and characterised the immune response in the draining popliteal lymph node 7 days later. This evidence concerns the gene ITSN2 and viral infectious disease.