FIGURE 3. Identification of the post-Aire mTEC population in Aire+/− mice.

(A) Representative samples of immunofluorescent co-stainings for β-gal antibody, Aire antibody, and enzymatic LacZ in the thymi from 6-week-old Aire+/− mice. There was no co-localization of Aire and enzymatic LacZ while β-gal staining co-localized with the majority of Aire staining and stained also all of the LacZ positive cells. DAPI was used for nuclear staining. (B) Representative immunohistochemical stainings of Aire and LacZ in Aire+/− mice at embryonic days e14.5 and e15.5. At e14.5 there was a clear signal of Aire but not LacZ, whereas at e15.5 both Aire and LacZ were present albeit always in different cells. (C) Summary of staining for Aire, LacZ, CK10, and involucrin during ontogeny of Aire+/− mice as determined by immunohistochemistry. Aire signal was first determined at e14.5, followed by LacZ and CK10 at e15.5, followed in turn by involucrin at e18.5. Shown are values from one representative out of two experiments. (D) Representative samples of co-stainings for LacZ and four epidermal differentiation markers in thymi of 6-week-old Aire+/− mice. (E) Summary of co-stainings for Aire vs. enzymatic LacZ and four epidermal differentiation markers in thymi of 6-week-old Aire+/− mice. The minority of CK6 and CK10 co-localized with Aire or with LacZ. LEKTI and involucrin showed almost no co-staining with Aire, whereas the majority of LEKTI and involucrin positive cells co-localized with LacZ. Values represent the range of at least three experiments, bars correspond to 40 μm.