Heme-iron status influences disease severity of NTHI.

Middle ear pressure was measured by tympanometry (mean ± S.D.) on each day following transbullar introduction of heme-iron replete (black squares) or restricted (gray circles) NTHI (A). Histopathology was assessed by examination of hematoxylin and eosin stained thin sections of naïve (B) or infected middle ear bullae 7 days following introduction of heme-iron replete (C, D) or restricted (E, F) NTHI. Scale bar = 25 µm (B), 50 µm (F), 100 µm (C, D, E). Abbreviations = Bone (B), mucosa (M), biofilm (Bio). Arrows denote capillaries.