Mice homozygous for Nfkb1 tm1Bal exhibit defective B cell responses, defective responses to infection, ... Stock No: 002849 |: p50- ... Targeted (Null/Knockout), Nfkb1, nuclear factor of kappa light polypeptide gene enhancer in B cells 1, p105 ... The 129-derived E14 ES cell line was used. ... Strain of Origin, 129P2/OlaHsd.