Primary amyloidosis A. Immunohistochemical and biochemical characterization
M M Picken1, K Pelton, B Frangione
1Department of Pathology, New York University Medical Center, New York 10016.
The American Journal of Pathology
|December 1, 1987
Summary
Primary amyloidosis, typically linked to immunoglobulin light chains, was found to be secondary amyloidosis (AA) protein in one patient. This suggests potential misdiagnosis and highlights organ-specific protein processing in amyloidosis.
Area of Science:
- Biochemistry
- Immunology
- Pathology
Background:
- Primary amyloidosis is often associated with immunoglobulin light chains (AL).
- Secondary amyloidosis (AA) typically results from chronic inflammation, malignancy, or familial Mediterranean fever, linked to serum amyloid A protein (SAA).
Observation:
- Amyloid fibril protein from a patient with primary systemic amyloidosis was identified as AA protein.
- Analysis included immunohistochemical, immunochemical, and amino terminal sequencing methods.
- AA protein monomers and dimers were extracted from both frozen and formalin-fixed paraffin-embedded kidney and spleen tissues.
Findings:
- The study identified AA protein in a case initially presumed to be primary amyloidosis.
- Different organ tissues showed variations in protein processing.
- Formalin-fixed paraffin-embedded lung tissue revealed high-molecular-weight bands and a 12,000-dalton fragment, suggesting polymerization and degradation.
Implications:
- This finding challenges the traditional classification of primary amyloidosis.
- It underscores the importance of accurate protein identification in amyloidosis diagnosis.
- Organ-specific protein processing may influence amyloid deposition and disease presentation.
More Related Videos
Related Concept Videos
03:03Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
03:03Amyloid Fibrils
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining, normally used to...
01:23Alzheimer Disease ll: Pathophysiology
Alzheimer disease involves structural changes in the brain that begin long before symptoms appear. The most distinctive features are extracellular neuritic plaques and intracellular neurofibrillary tangles.Neuritic plaques form in the cerebral cortex and around blood vessels. These plaques contain a dense core of beta-amyloid (Aβ)—a toxic protein fragment that clumps outside neurons. The core is surrounded by damaged neuronal extensions, as well as reactive astrocytes and microglia. Abnormal...