Figure 1. Transgenic mouse lines WAP-T and WAP-T_NP.

A. Transgene arrangements. In BALB/c WAP-T mice, the SV40 early gene region under control of the WAP promoter codes for the SV40 early proteins T-Ag, small t, and 17kT, e.g. in the T1 mice used in this study (above). WAP-T_NP mice, in addition, code for the strong MHC class I H2^d restricted LCMV T-cell epitope NP_118–126, inserted as a 33 bp oligonucleotide into a transformation-irrelevant carboxy-terminal region of T-Ag (for details see Schulze-Garg et al. [5]); NP6 and NP8 mice were selected for further studies (see Materials and methods). B. Distribution of T-Ag expressing cells in lactating mammary glands of T1, NP8, and NP6 mice (immune histology) The percentage of T-Ag positive cells detected in lactating mammary glands (7 days pp) of five individual T1, NP8, and NP6 mice each was evaluated.