Fig. 2: Moderate overexpression of Sim2s extends lactation performance.

A Cross-fostered pups were weighed daily to assess weight gain when nursed by WT and MMTV-Sim2s mice (n = 3 WT, n = 7 MMTV-Sim2s). B Representative H&E staining in mouse mammary gland sections at lactation day 10. C Experimental design for extended lactation studies. D Weekly weight gain of cross-fostered litters nursed by WT and MMTV-Sim2s mice during extended lactation study (n = 4 mice per group). E Crude milk fat percentage of milk collected from WT and MMTV-Sim2s mice during extended lactation study (n = 3 WT, n = 6 MMTV-Sim2s, milk could not be collected from every mouse at every timepoint). F Whole slide scans of H&E-stained mammary gland sections at day 42 of lactation. G Quantitation of epithelial and fat pad occupancy from whole slide scan H&E images (n = 4 mice per group). H Immunostaining for pSTAT3 in WT and MMTV-Sim2s mice mammary gland tissue at lactation day 42, and quantitation of pSTAT3-positive nuclei per image. Ten images per mouse were assessed (n = 2 mice per group). I Immunostaining for 8-OHdG at lactation day 28 in WT and MMTV-Sim2s mammary sections with quantification of 8-OHdG staining intensity normalized to number of nuclei. Error bars indicate the mean ± SD. *p < 0.05, **p < 0.01, scale bars: 100 μm.