A: Human islets from a nondiabetic subject and a subject with T2DM (upper panel) and from a wild-type (WT) and a human IAPP transgenic (HIP) rat (lower panel) stained for insulin (brown). Deposits of amyloid derived from IAPP are indicated by a white arrowhead. Original magnification:
×40. B: Alignment of IAPP ortholog proteins. Amino acid alignment of IAPP protein sequences identified in Homo sapiens (human, CAA39504),
human mutant (S20G), Macaca mulatto (monkey, XP_001098290), Felis catus (cat, NP_001036803), Mus musculus (mouse, NP_034621),
and Rattus norvegicus (rat, NP_036718). Dots correspond to conserved residues with human IAPP sequence. Red letters correspond
to the amyloidogenic sequence. C: Sections of islets from human IAPP transgenic mice labeled for oligomers (A11) and IAPP (5 nm and 10 nm gold, respectively).
IAPP- and oligomer-labeled aggregates were found adjacent to mitochondria (M), and mitochondrial integrity appeared to be
compromised (black arrow points to the aggregates penetrating mitochondria). Original magnification: ×120,000. This figure
originally appeared in an article by Gurlo et al. (50).