Florid Plaques Research Articles

Extracellular Amyloid Deposits in Alzheimer’s and Creutzfeldt–Jakob Disease: Similar Behavior of Different Proteins?

Neurodegenerative diseases are characterized by the deposition of specific protein aggregates, both intracellularly and/or extracellularly, depending on the type of disease. The extracellular occurrence of tridimensional structures formed by amyloidogenic proteins defines Alzheimer’s disease, in which plaques are composed of amyloid β-protein, while in prionoses, the same term “amyloid” refers to the amyloid prion protein. In this review, we focused on providing a detailed didactic description and differentiation of diffuse, neuritic, and burnt-out plaques found in Alzheimer’s disease and kuru-like, florid, multicentric, and neuritic plaques in human transmissible spongiform encephalopathies, followed by a systematic classification of the morphological similarities and differences between the extracellular amyloid deposits in these disorders. Both conditions are accompanied by the extracellular deposits that share certain signs, including neuritic degeneration, suggesting a particular role for amyloid protein toxicity.

1413. Surveillance of Variant Creutzfeldt Jakob Disease, Based on the Non-confirmatory Diagnostic Criteria of the EU Case Definition, Greece, 2014–2018

BackgroundVariant Creutzfeldt–Jakob disease (vCJD), is a form of CJD associated with consumption of tissues from cattle infected with bovine spongiform encephalopathy. Confirmation requires cerebral histopathologic examination, ascertaining spongiform change and extensive prion protein deposition with florid plaques. In Greece, the disease has been included in the Mandatory Notification System since 2004 however no reference laboratory has been available since 2009 due to low global occurrence. In 2014, the surveillance system was strengthened to also include possible and probable cases based on the non-confirmatory diagnostic criteria of the EU case definition. Hereby we present the results of the surveillance for 2014–2018.MethodsA new reporting form for CJD was introduced at the national level, including fields aligned with EU case definition criteria for vCJD (preconditions, clinical, diagnostic, and epidemiological). The non-confirmatory diagnostic criteria for the classification of probable and possible vCJD cases were based on examinations routinely available at hospitals, namely EEG and cerebral MRI. Reported CJD cases were assessed according to the fulfillment of required combinations of EU criteria for possible, probable, and confirmed vCJD cases.ResultsFrom 2014 to 2018, 37 CJD cases were reported, with a median age of 67 years (IQR: 58–73) concerning mostly females (71.3%, 95% CI: 56.7–85.9%). Among the reported cases, 6 (16.2%) fulfilled only the preconditions, 8 (21.6%) fulfilled the preconditions and the clinical criteria, 21 (56.8%) had a compatible EEG, and 7 (18.9%) had a compatible MRI brain scan. Confirmatory examination was not performed to any of the CJD cases; however, no case was classified as possible or probable vCJD based on the EU case definition.ConclusionNotification of CJD patients from 2014 to 2018 in Greece, yielded no vCJD cases. The possible re-emergence of vCJD renders continuous surveillance of the disease imperative. Current EU case definition can support the surveillance of vCJD, by screening CJD patients for possible and probable vCJD cases with the utilization of conventional diagnostic examinations, available in most hospitals.Disclosures All authors: No reported disclosures.

Acquired transmissibility of sheep-passaged L-type bovine spongiform encephalopathy prion to wild-type mice.

L-type bovine spongiform encephalopathy (L-BSE) is an atypical form of BSE that is transmissible to cattle and several lines of prion protein (PrP) transgenic mice, but not to wild-type mice. In this study, we examined the transmissibility of sheep-passaged L-BSE prions to wild-type mice. Disease-associated prion protein (PrPSc) was detected in the brain and/or lymphoid tissues during the lifespan of mice that were asymptomatic subclinical carriers, indicating that wild-type mice were susceptible to sheep-passaged L-BSE. The morphological characteristics of the PrPSc of sheep-passaged L-BSE included florid plaques that were distributed mainly in the cerebral cortex and hippocampus of subsequent passaged mice. The PrPSc glycoform profiles of wild-type mice infected with sheep-passaged L-BSE were similar to those of the original isolate. The data indicate that sheep-passaged L-BSE has an altered host range and acquired transmissibility to wild-type mice.

MRI detection of prion protein plaques in variant Creutzfeldt-Jakob disease.

In variant Creutzfeldt-Jakob disease (vCJD), cortical deposition of abnormal prion protein (PrP) aggregates as florid amyloid plaques occur.1 The 9.4T MRI resolves horizontal laminations of the isocortex.2 We scanned blocks of postmortem vCJD brain and a sporadic CJD control after passive staining with gadodiamide using a high-resolution 3D gradient echo sequence. Distinct hypointense foci on the MRI in vCJD (figure, A and C) but not control (figure, B) corresponded to PrP-amyloid plaques with greatest density in the central layers of the cortex on histology (figure, D–G). As human high-field systems become widespread, noninvasive monitoring of PrP-amyloid plaques may be of utility in future treatment trials.

Atypical Hansen’s disease presenting as florid verrucous plaques on the lower extremities: a case report

Verrucous leprosy is rare, with only 18 cases reported in the literature. Visceral involvement is frequent but often overlooked, causing significant morbidity and mortality. A 45-year-old Filipino male with a 16-year history of hyperpigmented, hypoesthetic plaques, amputated digits, enlarged ulnar nerve, and cardiovascular congestion was diagnosed with Hansen's disease-lepromatous type. He had multiple cauliflower-like nodules and plaques with foul-smelling discharge on the lower extremities presenting a diagnostic dilemma. After an exhaustive search, the causative agent for these verrucous nodules was confirmed to still be Mycobacterium leprae. In addition, he had glomerulonephritis, hypertension, congestive heart failure, deep venous thrombosis, neuritis, keratitis, and glaucoma, which are all complications of advanced leprosy and multiple attacks of erythema nodosum leprosum reactions. He was treated with a multibacillary regimen of Rifampicin, Dapsone, Clofazimine, and systemic corticosteroids, with remarkable improvement.

Experimental Transmission of Bovine Spongiform Encephalopathy (BSE) to Cynomolgus Macaques, a Non-Human Primate

Bovine spongiform encephalopathy (BSE) was transmitted to three macaques by intracerebral inoculation of a brain homogenate from affected cattle detected in Japan. All monkeys developed abnormal behavioral signs, such as intermittent anorexia and hyperekplexia, around 24 months after inoculation. Neuronal symptoms, such as tremor, myoclonic jerking, and paralysis, appeared 27-44 months after inoculation. These symptoms worsened and total paralysis ensued within a year after onset. The disease duration was approximately 8-12 months. Both the incubation period and the duration of disease were shortened in the secondary transmission experiment to macaques. Heavy accumulation of disease-causing conformer(s) of prion protein (PrP(Sc)), with a similar glycoform profile to the PrP(Sc) contained in the inoculum, and severe spongiform changes in the histology of the brain, confirmed the successful transmission of BSE to monkeys. Florid plaques, a characteristic histological hallmark of variant Creutzfeldt-Jakob disease, were prominent in the cerebral cortex, in which a prion antigen was detected by immunohistochemistry (IHC). PrP(Sc) was mostly confined to the central nervous system, although small amounts of PrP(Sc) accumulated in the peripheral nerves of monkeys, as detected by Western blotting (WB). Neither IHC nor WB detected PrP(Sc) in the lymphatic organs/tissues, such as the tonsils, spleen, and appendix.

Atypical L-Type Bovine Spongiform Encephalopathy (L-BSE) Transmission to Cynomolgus Macaques, a Non-Human Primate

A low molecular weight type of atypical bovine spongiform encephalopathy (L-BSE) was transmitted to two cynomolgus macaques by intracerebral inoculation of a brain homogenate of cattle with atypical BSE detected in Japan. They developed neurological signs and symptoms at 19 or 20 months post-inoculation and were euthanized 6 months after the onset of total paralysis. Both the incubation period and duration of the disease were shorter than those for experimental transmission of classical BSE (C-BSE) into macaques. Although the clinical manifestations, such as tremor, myoclonic jerking, and paralysis, were similar to those induced upon C-BSE transmission, no premonitory symptoms, such as hyperekplexia and depression, were evident. Most of the abnormal prion protein (PrP(Sc)) was confined to the tissues of the central nervous system, as determined by immunohistochemistry and Western blotting. The PrP(Sc) glycoform that accumulated in the monkey brain showed a similar profile to that of L-BSE and consistent with that in the cattle brain used as the inoculant. PrP(Sc) staining in the cerebral cortex showed a diffuse synaptic pattern by immunohistochemistry, whereas it accumulated as fine and coarse granules and/or small plaques in the cerebellar cortex and brain stem. Severe spongiosis spread widely in the cerebral cortex, whereas florid plaques, a hallmark of variant Creutzfeldt-Jakob disease in humans, were observed in macaques inoculated with C-BSE but not in those inoculated with L-BSE.

Predominant Involvement of the Cerebellum in Guinea Pigs Infected with Bovine Spongiform Encephalopathy (BSE)

This study reports the experimental transmission of bovine spongiform encephalopathy (BSE) to guinea pigs and describes the cerebellar lesions in these animals. Guinea pigs were inoculated intracerebrally with 10% brain homogenates from BSE-affected cattle. These animals were designated as the first passage. Second and third passages were subsequently performed. All guinea pigs developed infection at each passage. The mean incubation period of the first passage was 370 days post-infection (dpi) and this decreased to 307 dpi and 309 dpi for the second and third passages, respectively. Mild to severe spongiform degeneration and gliosis were observed in the cerebral cortex, thalamus and brainstem. In addition, the affected animals had marked pathological changes in the cerebellum characterized by severe cortical atrophy associated with Bergmann radial gliosis of the molecular layer and reduction in the width of the granular cell layer. Immunohistochemically, intense PrP(Sc) deposition and scattered plaque-like deposits were observed in the molecular and granular cell layers. Cerebellar lesions associated with severe atrophy of the cortex have not been reported in animal prion diseases, including in the experimental transmission of PrP(Sc) to small rodents. These lesions were similar to the lesions of human kuru or the VV2 variant of sporadic Creutzfeldt-Jakob disease, although typical kuru plaques or florid plaques were not observed in the affected animals.

Ultrastructural Characteristics (or Evaluation) of Creutzfeldt-Jakob Disease and Other Human Transmissible Spongiform Encephalopathies or Prion Diseases

The authors report on a large series of human prion diseases to establish ultrastructural characteristics that may be useful for their diagnosis. For Creutzfeldt-Jakob disease (CJD and its variant, vCJD) and fatal familial insomnia (FFI) only vacuolation (spongiform change) and the presence of tubulovesicular structures are consistent findings. Other changes, such as the presence of myelinated vacuoles, branching cisternae, neuroaxonal dystrophy, and autophagic vacuoles, were present in different proportions in either CJD or FFI, but they are nonspecific ultrastructural findings that can also occur in other neurodegenerative conditions. The hallmark of Gerstmann-Sträussler-Scheinker disease (GSS) and vCJD is the amyloid plaque, but plaques of GSS and kuru are different than those of vCJD. Whereas the former are typical unicentric kuru type or multicentric plaques, the latter are unicentric florid plaques. Also, kuru plaques are nonneuritic, whereas GSS florid plaques are usually neuritic; however, a proportion of plaques from GSS was also found to have nonneuritic characteristics. Thus, the presence or absence of dystrophic neurites is not a discriminatory factor for GSS and vCJD. Furthermore, plaques from GSS with different mutations were also slightly different. In GSS with mutations P102L, 232T, and A117V plaques were stellate while in 1 case with 144 base-pair insertion and in GSS-A117V, round plaques were also observed, and typical primitive neuritic plaques, i.e., composed of dystrophic neurites with little or no amyloid, were found only in a P102L case from the original Austrian family. In 2 cases of sporadic CJD, the kuru stellate plaque predominated.

Variant Creutzfeldt–Jakob disease: the first confirmed case from Portugal shows early onset, long duration and unusual pathology

We present clinical and autopsy findings in the first case of variant Creutzfeldt–Jakob disease diagnosed and confirmed in Portugal. Onset was at 11 years, the earliest onset reported, and the...

The first Japanese patient with variant Creutzfeldt‐Jakob disease (vCJD)

Eleven years after a brief visit to some European countries, a 48-year-old Japanese man developed writing difficulty, irritability and general fatigue. Then he complained of dysesthetic pains in his legs, for which benzodiazepines were prescribed. However, at the time pulvinar sign was retrospectively confirmed on brain MRI. Eighteen months after the onset, his gait became ataxic with rapid deterioration of mental status over the following several months. Thirty-one months after the onset, he became akinetic and mute with periodic synchronous discharges on EEG, and died at the age of 51. The total clinical course was approximately 43 months. Pathological examination revealed the characteristic alterations of spongiform encephalopathy, severe in the thalamus, moderate but widely spread in the cerebral cortices, and moderate in the cerebellum. Abundant amyloid plaques were easily identified in the cerebral cortex and the cerebellum on HE staining. Immunohistochemistry for abnormal prion protein (PrP(sc)) confirmed amyloid plaques in several forms, such as florid, uni- and multi-centric plaques as well as perineuronal and periaxonal deposits in the basal ganglia and synaptic patterns in the thalami. A Western blotting study identified type 2B protease-resistant PrP. This is the first Japanese patient who was definitely diagnosed as variant Creutzfeldt-Jakob disease (vCJD). The pathological findings were similar to those of previous reports of vCJD in the UK. However, the changes were much more severe both in degree and distribution, probably due to a longer duration of the illness than those in the UK.

Possible Case of Maternal Transmission of Feline Spongiform Encephalopathy in a Captive Cheetah

Feline spongiform encephalopathy (FSE) is considered to be related to bovine spongiform encephalopathy (BSE) and has been reported in domestic cats as well as in captive wild cats including cheetahs, first in the United Kingdom (UK) and then in other European countries. In France, several cases were described in cheetahs either imported from UK or born in France. Here we report details of two other FSE cases in captive cheetah including a 2nd case of FSE in a cheetah born in France, most likely due to maternal transmission. Complete prion protein immunohistochemical study on both brains and peripheral organs showed the close likeness between the two cases. In addition, transmission studies to the TgOvPrP4 mouse line were also performed, for comparison with the transmission of cattle BSE. The TgOvPrP4 mouse brains infected with cattle BSE and cheetah FSE revealed similar vacuolar lesion profiles, PrPd brain mapping with occurrence of typical florid plaques. Collectively, these data indicate that they harbor the same strain of agent as the cattle BSE agent. This new observation may have some impact on our knowledge of vertical transmission of BSE agent-linked TSEs such as in housecat FSE, or vCJD.

Ultrastructural study of florid plaques in variant Creutzfeldt–Jakob disease: a comparison with amyloid plaques in kuru, sporadic Creutzfeldt–Jakob disease and Gerstmann–Sträussler–Scheinker disease

Although the histological features of the amyloid plaques in variant Creutzfeldt-Jakob disease (vCJD) are distinct from those in other forms of prion disease [kuru, sporadic Creutzfeldt-Jakob disease (sCJD) and Gerstmann-Sträussler-Scheinker disease (GSS)], their ultrastructural features have only been described in a single case report. To study vCJD plaques systematically and compare them with plaques in kuru, sCJD, GSS and Alzheimer disease (AD). Amyloid plaques were studied by transmission electron microscopy and image analysis in five cases of vCJD, three cases of GSS, two cases of sCJD, one case of kuru and five cases of AD. Immunohistochemistry was performed on paraffin sections from one case of vCJD, two cases of GSS, one case of kuru and two cases of sCJD. The florid plaques in vCJD were either compact or more diffuse; in both forms, the radiating fibrils were organized into thick 'tongues', in contrast to kuru plaques. Dystrophic neurites (DNs) containing lysosomal electron-dense bodies or vesicles surrounded florid plaques. Microglial cells were found within florid plaques; occasional amyloid fibrils were identified in membrane-bound pockets of microglial cells. In vCJD, there was significant tau immunoreactivity in DNs around florid plaques while, in sCJD, GSS and kuru, minimal tau immunoreactivity was observed around plaques. The ultrastructure of the florid plaques and DNs in vCJD is more reminiscent of neuritic plaques in AD than kuru or multicentric plaques. These findings may reflect differences both in the strains of the transmissible agents responsible for these disorders and in host factors.

A quantitative study of the pathological changes in the cerebellum in 15 cases of variant Creutzfeldt-Jakob disease (vCJD).

To determine in the cerebellum in variant Creutzfeldt-Jakob disease (vCJD): (i) whether the pathology affected all laminae; (ii) the spatial topography of the pathology along the folia; (iii) spatial correlations between the pathological changes; and (iv) whether the pathology was similar to that of the common methionine/methionine Type 1 subtype of sporadic CJD. Sequential cerebellar sections of 15 cases of vCJD were stained with haematoxylin and eosin, or immunolabelled with monoclonal antibody 12F10 against prion protein (PrP) and studied using spatial pattern analysis. Loss of Purkinje cells was evident compared with control cases. Densities of the vacuolation and the protease-resistant form of prion protein (PrP(Sc)) (diffuse and florid plaques) were greater in the granule cell layer (GL) than the molecular layer (ML). In the ML, vacuoles and PrP(Sc) plaques occurred in clusters regularly distributed along the folia with larger clusters of vacuoles and diffuse plaques in the GL. There was a negative spatial correlation between the vacuoles and the surviving Purkinje cells in the ML. There was a positive spatial correlation between the vacuoles and diffuse PrP(Sc) plaques in the ML and GL. (i) all laminae were affected by the pathology, the GL more severely than the ML; (ii) the pathology was topographically distributed along the folia especially in the Purkinje cell layer and ML; (iii) pathological spread may occur in relation to the loop of anatomical connections involving the cerebellum, thalamus, cerebral cortex and pons; and (iv) there were pathological differences compared with methionine/methionine Type 1 sporadic CJD.

P2-213: Ultrastructural study of florid plaques in variant Creutzfeldt-Jakob disease: A comparison with kuru plaques in sporadic Creutzfeldt-Jakob and multicentric plaques of Gerstmann-Sträussler-Scheinker disease

P2-213: Ultrastructural study of florid plaques in variant Creutzfeldt-Jakob disease: A comparison with kuru plaques in sporadic Creutzfeldt-Jakob and multicentric plaques of Gerstmann-Sträussler-Scheinker disease

Time-course studies of 14-3-3 protein isoforms in cerebrospinal fluid and brain of primates after oral or intracerebral infection with bovine spongiform encephalopathy agent

Experimental transmission of bovine spongiform encephalopathy (BSE) to cynomolgus monkeys (Macaca fascicularis) is an animal model for variant Creutzfeldt-Jakob disease (vCJD). The presence of 14-3-3 proteins in cerebrospinal fluid (CSF) samples indicates neuronal destruction and is therefore used as a clinical biomarker. However, time-course studies using 14-3-3 proteins have not been performed until now in simian vCJD. The main goals of this study were to determine isoform patterns, to examine kinetics and to correlate the clinical course with the occurrence of this biomarker in simian vCJD. In monkeys dosed intracerebrally with BSE, the earliest clinical sign of illness was a drop in body weight that was detected months before the onset of mild neurological signs. Macaques dosed orally or intracerebrally with BSE developed neurological signs 4.3 (3.7-4.6) and 4.8 (2.9-6.0) years post-infection, respectively. 14-3-3beta- and -gamma-positive CSF samples were found around the time of onset of mild neurological signs, but not earlier. In contrast, 14-3-3epsilon and -eta isoforms were not detectable. 14-3-3 levels increased with time and were positively correlated with the degree of neurological symptoms. Post-mortem examination of brain samples revealed a positive correlation between PrP res and 14-3-3epsilon levels. Interestingly, florid plaques characteristic of human vCJD could not be detected in diseased monkeys. It was concluded that analysis of 14-3-3 proteins in CSF is a reliable tool to characterize the time course of brain degeneration in simian vCJD. However, there are differences in the clinical course between orally and intracerebrally infected animals that may influence the detection of other biomarkers.

Clinicopathologic characteristics of five autopsied cases of dura mater‐associated Creutzfeldt‐Jakob disease

We present five cases of dura mater-associated Creutzfeldt-Jakob disease (dura-CJD) that were analyzed clinicopathologically and review previous reports. The average age at dura mater transplantation was 54.4 +/- 7.3 years, and the average age at CJD onset was 66.0 +/- 8.2 years, with an average latency period of 11.6 +/- 1.1 years. The average age at death was 67.6 +/- 8.7 years, with an average CJD disease duration of 16.8 +/- 10.4 months. Symptoms of CJD onset in four patients who received dura mater transplantation below the cerebellar tent reflected cerebellar or brainstem dysfunction, whereas symptoms of one patient who received transplantation above the cerebellar tent reflected cerebral cortical involvement. All patients showed rapidly progressive cognitive impairment, and both periodic sharp-wave complexes on electroencephalogram and myoclonus were observed in the early disease stage. Neuropathologic evaluation showed one case of subacute spongiform encephalopathy and four cases of panencephalopathic-type CJD. Widespread cerebral neocortical, subcortical gray matter and cerebellar cortical involvement were observed to varying degrees, and severity tended to be associated with CJD disease duration. There were no instances of kuru plaques or florid plaques. Prion protein (PrP) immunostaining showed widespread synaptic-type PrP deposition. No differences between our dura-CJD cases and typical cases of sporadic CJD were found with respect to clinicopathologic findings, except history of dura mater transplantation. Although a specific association between the dura mater graft site and neuropathologic observations was not evaluated in the present study, the initial symptoms appear to be closely related to the graft site, indicating a direct transmission of CJD from the graft site to the adjacent brain.

Chronic wasting disease of deer and elk in transgenic mice: Oral transmission and pathobiology

To study the pathogenesis of chronic wasting disease (CWD) in deer and elk, transgenic (tg) mice were generated that expressed the prion protein (PrP) of deer containing a glycine at amino acid (aa) 96 and a serine at aa 225 under transcriptional control of the murine PrP promoter. This construct was introduced into murine PrP-deficient mice. As anticipated, neither non-tg mice nor PrP ko mice were susceptible when inoculated intracerebrally (i.c.) or orally with CWD brain material (scrapie pool from six mule deer) and followed for 600+ days (dpi). Deer PrP tg mice were not susceptible to i.c. inoculation with murine scrapie. In contrast, a fatal neurologic disease occurred accompanied by conversion of deer PrPsen to PrPres by western blot and immunohistochemistry after either i.c. inoculation with CWD brain into two lines of tg mice studied (312 + 32 dpi [mean + 2 standard errors] for the heterozygous tg line 33, 275 + 46 dpi for the heterozygous tg line 39 and 210 dpi for the homozygous tg line 33) or after oral inoculation (381 + 55 dpi for the homozygous tg line 33 and 370 + 26 dpi for the homozygous tg line 39). Kinetically, following oral inoculation of CWD brain, PrPres was observed by day 200 when mice were clinically healthy in the posterior surface of the dorsum of the tongue primarily in serous and mucous glands, in the intestines, in large cells at the splenic marginal zone that anatomically resembled follicular dendritic cells and macrophages and in the olfactory bulb and brain stem but did not occur in the cerebellum, cerebral cortex or hippocampus or in hearts, lungs and livers of infected mice. After 350 days when mice become clinically ill the cerebellum, cerebral cortex and hippocampus became positive for PrPres and displayed massive spongiosis, neuronal drop out, gliosis and florid plaques.

The first case of variant Creutzfeldt-Jakob disease in the Netherlands

The first case of variant Creutzfeldt-Jakob disease in the Netherlands

Bovine Spongiform Encephalopathy Agent in a Prion Protein (PrP)ARR/ARRGenotype Sheep after Peripheral Challenge: Complete Immunohistochemical Analysis of Disease‐Associated PrP and Transmission Studies to Ovine‐Transgenic Mice

Possible transmission of the bovine spongiform encephalopathy (BSE) agent to ovine species has been considered for several years. It has been recently demonstrated that the BSE agent, after intracerebral challenge, can infect sheep believed to be the most resistant genetically to prion diseases (prion protein [PrP](ARR/ARR) genotype). We report here the results of a detailed immunohistochemical analysis of the disease-associated PrP (PrP(d)) in all organs from a PrP(ARR/ARR) sheep infected with the BSE agent by a peripheral route. Because PrP(d) was detected in the brain in the absence of any clinical symptoms, transmission studies were also performed using a sensitive ovine-transgenic mouse model--Tg(OvPrP4)--that can identify the BSE agent on the basis of the occurrence of florid plaques in the mouse brain. The data indicated that these PrP(d) deposits were linked to the BSE agent and were associated with infectivity. This suggests that PrP(ARR/ARR) sheep may be silent carriers of the BSE agent.