FIG 2.
The biologically significant role of JAK1 is restricted to postlactational mammary gland remodeling. (A) (Top) Fluorescence images of unfixed mammary gland tissues to visualize expression of GFP in mammary ducts of a nulliparous JAK1 conditional knockout female (MMTV-Cre Jak1flox/flox CAG-LSL-GFP) and its littermate control expressing JAK1 (MMTV-Cre Jak1flox/+ CAG-LSL-GFP). (Bottom) The same glands from the top panels following carmine alum staining. Bar, 1 mm. (B) H&E-stained histological sections of mammary glands from females with mammary gland-specific JAK1 knockout and wild-type controls during lactation as well as at 1 and 3 days of involution. Bars, 100 μm. (C) Whole mounts of mammary glands from females with MMTV-Cre- and WAP-Cre-mediated mammary gland-specific JAK1 knockout and their JAK1-expressing controls at day 5 of involution. Bars, 2 mm. LN, lymph node.