Xth International Symposium on Amyloid and Amyloidosis April 18-22, 2004 (Selected Highlights) Tours,Loire Valley,France

We report a 40-year-old woman with a new transthyretin (TTR) variant, glutamine replacing leucine at residue 55 (Leu55Gln), who showed progressive somatic and autonomic neuropathy, glaucoma, and vitreous opacities. Symptoms of glaucoma appeared prior to the onset of the neuropathy. Sural nerve biopsy revealed amyloid deposition in the endoneurium, and immunohistochemical analysis was positive with anti-human TTR. Sequencing of the patient's DNA revealed the substitution of A for T at the second position of codon 55 of the TTR gene indicating an amino acid change from leucine to glutamine.     

The epidemiology of amyloidosis in Queensland,Australia

Published studies on the epidemiology of amyloidosis have relied on death certificate data for case ascertainment. We estimated the incidence and mortality burden of amyloidosis among residents of the Australian state, Queensland, aged ≥20 years for the years 1999–2013 based on case ascertainment from histopathology reports. Information systems for participating laboratories were scrutinised to identify histopathology reports that documented a diagnosis of amyloidosis. Case mortality status was determined via linkage to the National Death Index. A total of 447 cases of amyloidosis were identified, with a median age at diagnosis of 66 years. A plasma cell dyscrasia was identified in 72% of patients who had paraprotein studies performed. The estimated incidence for Queenslanders aged ≥20 years was 12·1 cases per million person years. The median survival was 2·45 years. Age at diagnosis, presence of a paraprotein, earlier year of diagnosis, and inner regional location of residence (compared with residence in a major city) were independently associated with reduced survival. Our data confirms previously reported incidence data for amyloidosis of approximately 10 cases per million patient years and indicates that survival for Queensland patients with amyloidosis is improving, though it remains poor for the elderly and patients with AL amyloidosis.     

Definition of organ involvement and treatment response in immunoglobulin light chain amyloidosis (AL): a consensus opinion from the 10th International Symposium on Amyloid and Amyloidosis, Tours, France, 18-22 April 2004

We undertook this study to develop uniformly accepted criteria for the definition of organ involvement and response for patients on treatment protocols for immunoglobulin light-chain amyloidosis (AL). A consensus panel was convened comprising 13 specialists actively involved in the treatment of patients with amyloidosis. Institutional criteria were submitted from each, and a consensus was developed defining each organ involved and the criteria for response. Specific criteria have been developed with agreed on definitions of organ and hematologic response as a result of discussions at the 10th International Symposium on Amyloid and Amyloidosis held in Tours, France, April 2004. These criteria now form the working definition of involvement and response for the purposes of future data collection and reporting. We report criteria that centers can now use to define organ involvement and uniform response criteria for reporting outcomes in patients with light-chain AL.     

One mutation,two distinct disease variants: unravelling the impact of transthyretin amyloid fibril composition

Although hereditary transthyretin (h‐ATTR) amyloidosis is a monogenetic disease, a large variation in its phenotype has been observed. The common hypothesis of amyloid fibril formation involves dissociation of the transthyretin (TTR) tetramer into monomers that after misfolding reassemble into amyloid fibrils. This notion is partly challenged by the finding of two distinct types of amyloid fibrils. One of these, type A, consists of C‐terminal ATTR fragments and full‐length TTR, whereas the other, type B, consists only of full‐length TTR. All organs of an individual patient contain ATTR deposits of either type A or type B fibrils, and the composition in each individual remains unchanged over time. The finding of two distinct types of ATTR fibrils suggests that there are at least two different pathways in operation for ATTR fibril formation. For the most common European mutation, TTR Val30Met, ATTR fibril composition is related to the outcome of liver transplantation, which is the first successful treatment for the disease, and the penetrance of the trait. In addition, the presence of C‐terminal ATTR fragments has an impact on the affinity for various tracers used for noninvasive imaging of amyloid depositions such as 99 m‐technetium‐diphosphono‐propanodicarboxylic acid scintigraphy and positron emission tomography utilizing Pittsburgh component B, and even for the gold standard diagnostic procedure, tissue biopsy stained by Congo red and examined under polarized light. The importance of amyloid fibril composition needs to be taken into consideration when designing clinical trials of treatment modalities, and also in the evaluation of diagnostic methods such as imaging techniques.     

Novel,Inexpensive, and Scalable Amyloid Fibril Formation Method

Wheat flour was used as a source of protein for the in vitro synthesis of Amyloid fibrils to develop a novel and inexpensive fabrication method. Amyloid fibrillation was confirmed by Thioflavin T Fluorescence, using confocal microscopy. A morphological study was carried out by transmission electron microscopy (TEM), which revealed the high aspect ratio of the amyloid fibrils formed via a novel process. An application of the amyloid fibers produced by the novel method is shown to be melatonin sensing. Tests showed that the amyloid samples had a measurable color variation dependent on the melatonin concentration. This newly derived process could prove to be a cost-effective tool for future nano-biomaterial applications in commercial and research settings.     

The relation of proteoglycans,serum amyloid P and Apo E to amyloidosis current status, 2000

Two direct binding enzyme-linked immunosorbent assays (ELISA) for human acute phase serum amyloid A isoforms (apoSAA¹ and apoSAA²) are described, a single antibody method for serum and plasma samples and a double antibody method for tissue culture supernatants. Both methods employ polyvalent, monospecific rabbit anti-human apoSAA antiserum that does not react with constitutive apoSAA in plasma or tissue culture samples. In the presence of 3M KBr, pH 9.6, all apoSAA isoforms are passively adsorbed to microtiter plate wells in quantities proportional to their concentrations. The absolute concentrations of total acute phase apoSAA isoforms in samples can be determined from a standard curve constructed from samples of known apoSAA concentration incubated at the same time. For clinical evaluation of serum and plasma specimens, apoSAA is bound to microtiter wells at ambient temperature (～25°C) after which its concentration is determined directly with horseradish peroxidase (HRP)-conjugated anti-apoSAA immunoglobulins. The sensitivity for detection of acute phase apoSAA isoforms in plasma was found to be 1 μMg/ml. In order to measure apoSAA in tissue culture supernatants, apoSAA is bound to wells at 37°C and detected using anti-rabbit apoSAA antiserum and HRP-conjugated goat anti-rabbit immunoglobulins; the sensitivity for detection of acute phase isoforms was I μg/ml.     

Cortical petechial hemorrhage,subarachnoid hemorrhage and corticosteroid-responsive leukoencephalopathy in a patient with cerebral amyloid angiopathy

We describe a 69-year-old woman who developed subacute onset cognitive decline after hitting the left side of her head. Cerebral spinal fluid showed yellowish discoloration with highly elevated protein content. FLAIR MRI revealed diffuse high signal intensity in all cortical sulci, and leptomeningeal enhancement in the left cerebral hemisphere was seen in the T1 image after contrast administration. She was treated with a corticosteroid. Consciousness disturbance was temporarily relieved but again worsened, resulting in an apathetic state due to communicating hydrocephalus. A shunt tube was placed in her right lateral ventricle. A brain biopsy disclosed multiple cortical microbleeds and heavy deposition of Aβ-immuoreactive amyloid on vascular walls. Inflammatory mononuclear cells surrounded a few leptomeningeal vessels. After the operation her condition further deteriorated and she fell into a coma. MRI showed diffuse swelling of the right cerebral white matter. She again received high-dose corticosteroid and gradually recovered during the following 2 months. On MRI the vast majority of abnormal signals in the right cerebral white matter disappeared. An initial manifestation of this patient was possibly caused by multiple microhemorrhages from fragile cortical and subarachnoid vessels with Aβ-amyloid deposition, which was triggered by head trauma. CAA-related inflammation possibly worsened this condition. Additionally, surgical intervention for communicating hydrocephalus might have induced cerebral amyloid angiopathy (CAA)-related leukoencephalopathy in her right cerebral hemisphere. These CAA-derived manifestations are unusual and high-dose corticosteroids seems to be useful for vascular events in CAA patients.     

Amyloid seeds formed by cellular uptake,concentration, and aggregation of the amyloid-beta peptide

One of the neuropathological hallmarks of Alzheimer''s disease (AD) is the amyloid plaque, primarily composed of aggregated amyloid-beta (Aβ) peptide. In vitro, Aβ_1–42, the major alloform of Aβ found in plaques, self-assembles into fibrils at micromolar concentrations and acidic pH. Such conditions do not exist in the extracellular fluid of the brain where the pH is neutral and Aβ concentrations are in the nanomolar range. Here, we show that extracellular soluble Aβ (sAβ) at concentrations as low as 1 nM was taken up by murine cortical neurons and neuroblastoma (SHSY5Y) cells but not by human embryonic kidney (HEK293) cells. Following uptake, Aβ accumulated in Lysotracker-positive acidic vesicles (likely late endosomes or lysosomes) where effective concentrations (>2.5 μM) were greater than two orders of magnitude higher than that in the extracellular fluid (25 nM), as quantified by fluorescence intensity using laser scanning confocal microscopy. Furthermore, SHSY5Y cells incubated with 1 μM Aβ_1–42 for several days demonstrated a time-dependent increase in intracellular high molecular weight (HMW) (>200 kDa) aggregates, which were absent in cells grown in the presence of Aβ_1–40. Homogenates from these Aβ_1–42-loaded cells were capable of seeding amyloid fibril growth. These results demonstrate that Aβ can be taken up by certain cells at low physiologically relevant concentrations of extracellular Aβ, and then concentrated into endosomes/lysosomes. At high concentrations, vesicular Aβ aggregates to form HMW species which are capable of seeding amyloid fibril growth. We speculate that extrusion of these aggregates may seed extracellular amyloid plaque formation during AD pathogenesis.     

血清淀粉样蛋白A与胰岛素抵抗及糖尿病肾病

研究提示,胰岛素抵抗和糖尿病肾病都是慢性非特异性炎性反应过程.血清淀粉样蛋白A(SAA)作为一种急性时相反应蛋白,能够刺激多种免疫活细胞,产生大量炎性细胞因子,介导炎性反应,并能诱导单核细胞表达趋化因子,使各种炎性细胞尤其是单核/巨噬细胞及T细胞聚集到病变部位.而这种免疫和炎性反应过程可能促进了胰岛素抵抗和糖尿病肾病的发生和发展.     

Serum Amyloid A, Procalcitonin, and C-Reactive Protein in Early Assessment of Severity of Acute Pancreatitis

Amyloid A (SAA) and procalcitonin (PCT) have been reported as useful indicators of inflammation. Our aim was to assess the utility of SAA and PCT in establishing the severity of acute pancreatitis in comparison to C-reactive protein (CRP): Thirty-one patients with acute pancreatitis enrolled within 24 hr from the onset of pain and 31 healthy subjects were studied. Nineteen patients had mild acute pancreatitis, and 12 had severe pancreatitis. Serum SAA, PCT, and CRP were measured in all subjects at admission and, in acute pancreatitis patients, during the following five days. Patients with acute pancreatitis had serum concentrations of SAA, PCT, and CRP significantly higher (P < 0.001) than those of healthy subjects during the entire study period. Using cutoff values ranging from 240 to 250 mg/liter for SAA, from 0.252 to 0.255 ng/ml for PCT, and from 12.8 to 12.9 mg/dl for CRP, the sensitivity (calculated on patients with severe pancreatitis), the specificity (calculated on patients with mild pancreatitis), and the efficiency (calculated as the percentage of correct classifications) were 76.8%, 69.3%, and 72.4% for SAA; 21.7%, 83.2%, and 58.2% for PCT; and 60.9%, 89.1%, and 77.6% for CRP. In conclusion, the sensitivity of SAA is significantly higher than that of PCT and CRP in assessing the severity of pancreatitis, whereas PCT and CRP had a specificity significantly higher than SAA. The accuracy and efficiency were similar for SAA and CRP, and both these markers had an accuracy and efficiency significantly higher than those of PCT.     

Chemical typing of porcine systemic amyloid as AA-amyloid

Systemic AA amyloidosis is frequently reported in a wide variety of domestic and wild animal species. Porcine amyloidosis is rare and the amyloid has not been typed chemically thus far. In the present study, we have extracted porcine amyloid from formalin-fixed tissue sections. By subsequent amino acid sequencing, an N-terminal fragment was obtained identifying porcine systemic amyloid as AA amyloid. The N-terminal sequence had a great homology to bovine and ovine SAA1, suggesting that pig AA amyloid is derived from the systemic isoform of SAA. It is argued that the low incidence of amyloidosis in pigs is not likely to be attributed to unique features of porcine amyloid precursor protein. Elucidation of the basis for the high apparent resistance of pigs against amyloidosis may yield important clues for treatment and prevention of amyloidosis in other species. This is the first report on chemical identification of porcine amyloid.     

Amyloid fibril protein nomenclature: 2010 recommendations from the nomenclature committee of the International Society of Amyloidosis

A system of amyloid fibril nomenclature based on the chemical identity of the amyloid fibril forming protein is recommended. This system has been in use for approximately 40 years, but current literature remains confused with clinical and histochemical designations used when the amyloid disease processes were poorly understood. To be designated an amyloid fibril protein, the protein must occur in tissue deposits and exhibit affinity for Congo red and green birefringence when viewed by polarisation microscopy. Furthermore, the protein must have been unambiguously characterised by protein sequence analysis (DNA sequencing in the case of familial diseases). Current nomenclature lists of 27 human and nine animal fibril proteins are provided together with a list of eight inclusion bodies that exhibit some of the properties of amyloid fibrils.     

Electrochemical and homogeneous electron transfers to the Alzheimer amyloid-β copper complex follow a preorganization mechanism

Deciphering the electron transfer reactivity characteristics of amyloid β-peptide copper complexes is an important task in connection with the role they are assumed to play in Alzheimer’s disease. A systematic analysis of this question with the example of the amyloid β-peptide copper complex by means of its electrochemical current–potential responses and of its homogenous reactions with electrogenerated fast electron exchanging osmium complexes revealed a quite peculiar mechanism: The reaction proceeds through a small fraction of the complex molecules in which the peptide complex is “preorganized” so as the distances and angles in the coordination sphere to vary minimally upon electron transfer, thus involving a remarkably small reorganization energy (0.3 eV). This preorganization mechanism and its consequences on the reactivity should be taken into account for reactions involving dioxygen and hydrogen peroxide that are considered to be important in Alzheimer’s disease through the production of harmful reactive oxygen species.     

Noninvasive Identification of ATTRwt Cardiac Amyloid: The Re-emergence of Nuclear Cardiology

More than half of all subjects with chronic heart failure are older adults with preserved ejection fraction (HFpEF). Effective therapy for this condition is yet to be delineated by clinical trials, suggesting that a greater understanding of underlying biologic mechanisms is needed, especially for the purpose of clinical intervention and future clinical trials. Amyloid infiltration of the myocardium is an underappreciated contributing factor to HFpEF that is often caused by misfolded monomers or oligomers of the protein transthyretin. While previously called senile cardiac amyloidosis and traditionally requiring endomyocardial biopsy for diagnosis, advances in our pathophysiologic understanding of this condition, coupled with nuclear imaging techniques using bone isotopes that can diagnose this condition noninvasively and the development of potential therapies, have resulted in a renewed interest in this previously considered “rare” condition. This reviewer focuses on the re-emergence of nuclear cardiology using pyrophosphate agents that hold promise for early, noninvasive identification of affected individuals.     

Formation of experimental murine AA amyloid fibrils in SAP-deficient mice: High resolution ultrastructural study

Previously, the role of the serum amyloid P component (SAP) in the deposition of murine AA amyloid has been examined in SAP-deficient mice in which the deposition was significantly retarded. In this study, AA amyloid fibrillogenesis in SAP-deficient mice was examined ultrastructurally. The fibrils of wild type mice were made up of a microfibril-like main body composed of SAP, chondroitin sulfate proteoglycan (CSPG), and outermost heparan sulfate proteoglycan (HSPG), and associated on its surface were 3 nm wide AA protein ‘helical rods’, a possible suitable form for Congo red staining. In SAP-deficient mice, fibrils of a similar appearance were also noted among an overwhelming amount of amorphous material, but the AP-containing main body of the fibril was replaced by elongated irregular aggregates of CSPG. The mechanism of retardation of AA amyloid induction in SAP-deficient mice has not yet been clear. It may be caused by possible slower formation of a ‘substitute’ core. Also, slower formation of AA helical rods may be possible due to the difference in the core material to which AA protein is attached. If it is so, it may limit the extent of Congo red staining, resulting in underestimation of the actual amount of AA protein.     

The significance of carpal tunnel syndrome in transthyretin Val30Met familial amyloid polyneuropathy

Carpal tunnel syndrome (CTS) is frequently reported in association with amyloidosis. We determined the significance of CTS in transthyretin Val30Met-associated familial amyloid polyneuropathy (FAP ATTR Val30Met) by comparing the electrophysiological indices of the median and ulnar nerves in 58 patients. As a whole, sensory nerve conduction velocity (SCV) was slowed and distal motor latency (DML) was prolonged to a similar extent in the median and ulnar nerves in these patients. The extent of abnormalities in the median nerve was almost similar to that in the ulnar nerve in both early-onset cases from endemic foci and late-onset cases from non-endemic areas. In age-matched idiopathic patients with CTS (20 patients, 27 hands), the slowing of SCV and the prolongation of DML in the median nerve were significant, while the slowing of motor conduction velocity was much less compared to FAP ATTR Val30Met patients. Although concomitant lesions in the ulnar nerve entrapment site at the wrist cannot be excluded, these findings indicate that CTS is not the sole distinctive feature in the majority of FAP ATTR Val30Met patients. The electrophysiological abnormality at the distal portion of the median nerve may be a consequence of polyneuropathy rather than an entrapment injury.