Apolipoprotein C-III (ApoC-III) amyloidosis is an extremely rare systemic amyloidosis previously reported only in humans and white lions. This report describes the first case of ApoC-III amyloidosis i Show more
Apolipoprotein C-III (ApoC-III) amyloidosis is an extremely rare systemic amyloidosis previously reported only in humans and white lions. This report describes the first case of ApoC-III amyloidosis in an Asiatic lion (16-year-old male) that died with clinical manifestations of renal failure. Histopathological and ultrastructural examinations identified amyloid deposits predominantly at the renal corticomedullary junction. Mass spectrometry and immunohistochemistry identified ApoC-III as an amyloid precursor protein. Sequencing of the lion's APOC3 gene found no pathogenic mutations, although lion species have a unique M30V substitution compared with other Panthera species, which may predispose them to Apo-CIII amyloidosis. This first case of a non-white lion indicates that ApoC-III amyloidosis is not restricted to white lions. Show less
The purpose of this study is to identify and visualize the spatial distribution of proteins present in amyloid corneal deposits of TGFBI-CD patients using Mass Spectrometry Imaging (MSI) and compare i Show more
The purpose of this study is to identify and visualize the spatial distribution of proteins present in amyloid corneal deposits of TGFBI-CD patients using Mass Spectrometry Imaging (MSI) and compare it with healthy control cornea. Corneal Dystrophies (CD) constitute a group of genetically inherited protein aggregation disorders that affects different layers of the cornea. With accumulated protein deposition, the cornea becomes opaque with decreased visual acuity. CD affecting the stroma and Bowman's membrane, is associated with mutations in transforming growth factor β-induced (TGFBI) gene. MALDI-Mass Spectrometry Imaging (MSI) is performed on 2 patient corneas and is compared with 1 healthy control cornea using a 7T-MALDI-FTICR. Molecular images obtained are overlaid with congo-red stained sections to visualize the proteins associated with the corneal amyloid aggregates. MALDI-MSI provides a relative abundance and two dimensional spatial protein signature of key proteins (TGFBIp, Apolipoprotein A-I, Apolipoprotein A-IV, Apolipoprotein E, Kaliocin-1, Pyruvate Kinase and Ras related protein Rab-10) in the patient deposits compared to the control. This is the first report of the anatomical localization of key proteins on corneal tissue section from CD patients. This may provide insight in understanding the mechanism of amyloid fibril formation in TGFBI-corneal dystrophy. Show less