Fig. 3.

Transgenic Fra-2 expression in inflammatory cells is not required for pulmonary fibrosis in fra-2^tg mice. (a–c) Representative Chromotrop Anilinblue (CAB) stainings of lungs after irradiation and bone marrow reconstitution using wild-type (wt) and fra-2^tg (tg) animals as recipients and donors. The wild-type control is shown in a. Wild-type recipients reconstituted with fra-2^tg bone marrow (BM) did not develop pulmonary fibrosis (b), whereas fra-2^tg animals reconstituted with wild-type bone marrow developed the disease (c). Collagen is stained in blue. (d–g) Breeding of fra-2^tg animals into a rag2-deficient genetic background (no functional B and T cells) did not ameliorate pulmonary fibrosis. Shown are CAB stainings demonstrating comparable collagen deposition (blue) in fra-2^tg/rag2^+/− (d) and fra-2^tg/rag2^−/− (e) mice (n = 6). Lung weight (f) (n = 6) and mortality (g) (n ≥ 10) were equally increased in fra-2^tg and fra-2^tg/rag2^−/− mice.