Neuropathology of the sporadic and variant subtypes of Creutzfeldt-Jakob disease:a comparative quantitative study

The objective of the present study was to compare quantitatively the neuropathology of two subtypes of Creutzfeldt-Jakob disease (CJD), viz., sporadic CJD (sCJD) and variant CJD (vCJD). The vacuolation (‘spongiform change’), surviving neurons, glial cell nuclei, and deposits of the disease form of prion protein (PrPsc) were quantified in histological sections of the cerebral cortex, hippocampus, and cerebellum in 11 cases of sCJD and 15 cases of vCJD. Three aspects of the quantitative pathology of each histological feature were studied: overall abundance (density or coverage), spatial distribution parallel to the tissue boundary, and laminar distribution across gyri of the cerebral cortex. Overall vacuole density was greater in sCJD than in vCJD in some regions while overall neuronal densities were greater in vCJD. In cerebral cortex, vacuoles and PrPsc deposits were distributed in clusters which exhibited a regular distribution parallel to the pia mater, this type of spatial pattern being more frequent in sCJD than in vCJD. In some cortical gyri there were differences in laminar distribution between subtypes, viz. the vacuolation was more generally distributed across cortical laminae in sCJD, neuronal loss was often greater in upper laminae in vCJD but in lower laminae in sCJD, and PrPsc deposits were more frequently distributed in upper laminae in vCJD but in lower laminae in sCJD. A significant gliosis affected lower cortical laminae in both sCJD and vCJD. Hence, there were differences in degeneration of cerebral cortex, hippocampus, and cerebellum in sCJD and vCJD, which may reflect variations in disease aetiology and propagation of PrPsc through the brain.

Comparative quantitative neuropathology of the sporadic and variant subtypes of Creutzfeldt-Jakob disease

The objective of the present study was to compare quantitatively the neuropathology of two subtypes of Creutzfeldt-Jakob disease (CJD), viz., sporadic CJD (sCJD) and variant CJD (vCJD). The vacuolation (‘spongiform change’), surviving neurons, glial cell nuclei, and deposits of the disease form of prion protein (PrPsc) were quantified in histological sections of the cerebral cortex, hippocampus, and cerebellum in 11 cases of sCJD and 15 cases of vCJD. Three aspects of the quantitative pathology of each histological feature were studied: overall abundance (density or coverage), spatial distribution parallel to the tissue boundary, and laminar distribution across gyri of the cerebral cortex. Overall vacuole density was greater in sCJD than in vCJD in some regions while overall neuronal densities were greater in vCJD. In cerebral cortex, vacuoles and PrPsc deposits were distributed in clusters which exhibited a regular distribution parallel to the pia mater, this type of spatial pattern being more frequent in sCJD than in vCJD. In some cortical gyri there were differences in laminar distribution between subtypes, viz. the vacuolation was more generally distributed across cortical laminae in sCJD, neuronal loss was often greater in upper laminae in vCJD but in lower laminae in sCJD, and PrPsc deposits were more frequently distributed in upper laminae in vCJD but in lower laminae in sCJD. A significant gliosis affected lower cortical laminae in both sCJD and vCJD. Hence, there were differences in degeneration of cerebral cortex, hippocampus, and cerebellum in sCJD and vCJD, which may reflect variations in disease aetiology and propagation of PrPsc through the brain.

Binding and hydrodynamic properties of muscarinic receptor subtypes solubilized in 3-(3-cholamidopropyl)dimethylammonio-2-hydroxy-1-propanesulfonate

The muscarinic receptor from the cerebral cortex, heart, and lacrimal gland can be solubilized in the zwitterionic detergent 3-(3-cholamidopropyl)dimethylammonio-2-hydroxy-1-propane sulfonate (CHAPSO) with retention of high affinity [3H]N-methyls-copolamine binding. However, in this detergent there are significant differences in the binding properties of the receptors, compared with those observed in membranes and digitonin solution. Some agents retain a degree of selectivity. In the heart and cortex, agonists can bind with high affinity to a receptor-GTP-binding protein complex. A second, lower affinity, agonist binding state is also present, which resembles a class of sites seen in membranes but not in digitonin solution. The high affinity agonist binding state has been resolved from the lower affinity state on sucrose density gradient centrifugation. Hydrodynamic analysis suggests that the high affinity state is approximately 110,000 Da larger than the lower affinity state. The binding properties of the receptor in CHAPSO can be altered to those seen in digitonin by exchanging detergents after CHAPSO solubilization.

Quantitative microscopic analysis of histological sections of brain tissue

This article reviews methods for quantifying the abundance of histological features in thin tissue sections of brain such as neurons, glia, blood vessels, and pathological lesions. The sampling methods by which quantitative measures can be obtained are described. In addition, methods are described for determining the spatial pattern of an object and for measuring the degree of spatial correlation between two or more histological features.

Quantitative differences in beta/A4 protein subtypes in the parahippocampal gyrus and frontal cortex in Alzheimer's disease

The density of diffuse, primitive and classic beta/A4 protein deposits was estimated in sulci and gyri in the frontal cortex and parahippocampal gyrus (PHG) in 8 cases of Alzheimer's disease. Total beta/A4 deposit density was similar in the frontal cortex and PHG but the ratio of primitive and classic deposits to the total was greater in the PHG compared with the frontal cortex. Total beta/A4 deposit density was greater in the depths of the sulci, but the proportions of the various beta/A4 subtypes were similar in sulci and gyri. Hence, increased density of primitive and classic deposits in the PHG could reflect enhanced conversion of diffuse to mature deposits whereas increased density of mature beta/A4 subtypes in sulci versus gyri may reflect increased beta/A4 deposition in the sulci.

The identification of pathological subtypes of Alzheimer's disease using cluster analysis

A culster analysis was performed on 78 cases of Alzheimer's disease (AD) to identify possible pathological subtypes of the disease. Data on 47 neuropathological variables, inculding features of the gross brain and the density and distribution of senile plaques (SP) and neurofibrillary tangles (NFT) were used to describe each case. Cluster analysis is a multivariate statistical method which combines together in groups, AD cases with the most similar neuropathological characteristics. The majority of cases (83%) were clustered into five such groups. The analysis suggested that an initial division of the 78 cases could be made into two major groups: (1) a large group (68%) in which the distribution of SP and NFT was restricted to a relatively small number of brain regions, and (2) a smaller group (15%) in which the lesions were more widely disseminated throughout the neocortex. Each of these groups could be subdivided on the degree of capillary amyloid angiopathy (CAA) present. In addition, those cases with a restricted development of SP/NFT and CAA could be divided further into an early and a late onset form. Familial AD cases did not cluster as a separate group but were either distributed between four of the five groups or were cases with unique combinations of pathological features not closely related to any of the groups. It was concluded that multivariate statistical methods may be of value in the classification of AD into subtypes. © 1994 Springer-Verlag.

Measuring the spatial arrangement patterns of pathological lesions in histological sections of brain tissue

The development of abnormal protein aggregates in the form of extracellular plaques and intracellular inclusions is a characteristic feature of many neurodegenerative diseases such as Alzheimer's disease (AD), Creutzfeldt-Jakob disease (CJD) and the fronto-temporal dementias (FTD). An important aspect of a pathological protein aggregate is its spatial topography in the tissue. Lesions may not be randomly distributed within a histological section but exhibit spatial pattern, a departure from randomness either towards regularity or clustering. Information on the spatial pattern of a lesion may be useful in elucidating its pathogenesis and in studying the relationships between different lesions. This article reviews the methods that have been used to study the spatial topography of lesions. These include simple tests of whether the distribution of a lesion departs significantly from random using randomized points or sample fields, and more complex methods that employ grids or transects of contiguous fields and which can detect the intensity of aggregation and the sizes, distribution and spacing of the clusters. The usefulness of these methods in elucidating the pathogenesis of protein aggregates in neurodegenerative disease is discussed.

Methods of studying the planar distribution of objects in histological sections of brain tissue

This article reviews the statistical methods that have been used to study the planar distribution, and especially clustering, of objects in histological sections of brain tissue. The objective of these studies is usually quantitative description, comparison between patients or correlation between histological features. Objects of interest such as neurones, glial cells, blood vessels or pathological features such as protein deposits appear as sectional profiles in a two-dimensional section. These objects may not be randomly distributed within the section but exhibit a spatial pattern, a departure from randomness either towards regularity or clustering. The methods described include simple tests of whether the planar distribution of a histological feature departs significantly from randomness using randomized points, lines or sample fields and more complex methods that employ grids or transects of contiguous fields, and which can detect the intensity of aggregation and the sizes, distribution and spacing of clusters. The usefulness of these methods in understanding the pathogenesis of neurodegenerative diseases such as Alzheimer's disease and Creutzfeldt-Jakob disease is discussed. © 2006 The Royal Microscopical Society.

Measuring the degree of spatial correlation between histological features in thin sections of brain tissue

Histological features visible in thin sections of brain tissue, such as neuronal perikarya, blood vessels, or pathological lesions may exhibit a degree of spatial association or correlation. In neurodegenerative disorders such as AD, Pick's disease, and CJD, information on whether different types of pathological lesion are spatially correlated may be useful in elucidating disease pathogenesis. In the present article the statistical methods available for studying spatial association in histological sections are reviewed. These include tests of interspecific association between two or more histological features using χ2 contingency tables, measurement of 'complete' and 'absolute' association, and more complex methods that use grids of contiguous samples. In addition, the use of correlation matrices and stepwise multiple regression methods are described. The advantages and limitations of each method are reviewed and possible future developments discussed.

Analysis of spatial patterns in histological sections of brain tissue using a method based on regression

A method of determining the spatial pattern of any histological feature in sections of brain tissue which can be measured quantitatively is described and compared with a previously described method. A measurement of a histological feature such as density, area, amount or load is obtained for a series of contiguous sample fields. The regression coefficient (β) is calculated from the measurements taken in pairs, first in pairs of adjacent samples and then in pairs of samples taken at increasing degrees of separation between them, i.e. separated by 2, 3, 4,..., n units. A plot of β versus the degree of separation between the pairs of sample fields reveals whether the histological feature is distributed randomly, uniformly or in clusters. If the feature is clustered, the analysis determines whether the clusters are randomly or regularly distributed, the mean size of the clusters and the spacing of the clusters. The method is simple to apply and interpret and is illustrated using simulated data and studies of the spatial patterns of blood vessels in the cerebral cortex of normal brain, the degree of vacuolation of the cortex in patients with Creutzfeldt-Jacob disease (CJD) and the characteristic lesions present in Alzheimer's disease (AD). Copyright (C) 2000 Elsevier Science B.V.

Analysis of spatial patterns in histological sections of brain tissue

A method is described which enables the spatial pattern of discrete objects in histological sections of brain tissue to be determined. The method can be applied to cell bodies, sections of blood vessels or the characteristic lesions which develop in the brain of patients with neurodegenerative disorders. The density of the histological feature under study is measured in a series of contiguous sample fields arranged in a grid or transect. Data from adjacent sample fields are added together to provide density data for larger field sizes. A plot of the variance/mean ratio (V/M) of the data versus field size reveals whether the objects are distributed randomly, uniformly or in clusters. If the objects are clustered, the analysis determines whether the clusters are randomly or regularly distributed and the mean size of the clusters. In addition, if two different histological features are clustered, the analysis can determine whether their clusters are in phase, out of phase or unrelated to each other. To illustrate the method, the spatial patterns of senile plaques and neurofibrillary tangles were studied in histological sections of brain tissue from patients with Alzheimer's disease.

The use of multivariate methods in the identification of subtypes of Alzheimer's disease: a comparison of principal components and cluster analysis

Two contrasting multivariate statistical methods, viz., principal components analysis (PCA) and cluster analysis were applied to the study of neuropathological variations between cases of Alzheimer's disease (AD). To compare the two methods, 78 cases of AD were analyzed, each characterised by measurements of 47 neuropathological variables. Both methods of analysis revealed significant variations between AD cases. These variations were related primarily to differences in the distribution and abundance of senile plaques (SP) and neurofibrillary tangles (NFT) in the brain. Cluster analysis classified the majority of AD cases into five groups which could represent subtypes of AD. However, PCA suggested that variation between cases was more continuous with no distinct subtypes. Hence, PCA may be a more appropriate method than cluster analysis in the study of neuropathological variations between AD cases.

Analysis of population dispersion in histological sections

Stereology and other image analysis methods have enabled rapid and objective quantitative measurements to be made on histological sections. These mesurements may include total volumes, surfaces, lengths and numbers of cells and blood vessels or pathological lesions. Histological features, however, may not be randomly distributed across a section but exhibit 'dispersion', a departure from randomness either towards regularity or aggregation. Information of population dispersion may be valuable not only in understanding the two-or three-dimensional structure but also in elucidating the pathogenesis of lesions in pathological conditions. This article reviews some of the statistical methods available for studying dispersion. These range from simple tests of whether the distribution of a histological faeture departs significantly from random to more complex methods which can detect the intensity of aggregation and the sizes, distribution and spacing of the clusters.

A comparison of histological and immunohistochemical methods for quantifying the pathological lesions of Pick's disease

Counts of Pick bodies (PB), Pick cells (PC), senile plaques (SP) and neurofibrillary tangles (NFT) were made in the frontal and temporal cortex from patients with Pick's disease (PD). Lesions were stained histologically with hematoxylin and eosin (HE) and the Bielschowsky silver impregnation method and labeled immunohistochemically with antibodies raised to ubiquitin and tau. The greatest numbers of PB were revealed by immunohistochemistry. Counts of PB revealed by ubiquitin and tau were highly positively correlated which suggested that the two antibodies recognized virtually identical populations of PB. The greatest numbers of PC were revealed by HE followed by the anti-ubiquitin antibody. However, the correlation between counts was poor, suggesting that HE and ubiquitin revealed different populations of PC. The greatest numbers of SP and NFT were revealed by the Bielschowsky method indicating the presence of Alzheimer-type lesions not revealed by the immunohistochemistry. In addition, more NFT were revealed by the anti-ubiquitin compared with the anti-tau antibody. The data suggested that in PD: (i) the anti-ubiquitin and anti-tau antibodies were equally effective at labeling PB; (ii) both HE and anti-ubiquitin should be used to quantitate PC; and (iii) the Bielschowsky method should be used to quantitate SP and NFT.

The spatial patterns of β/A4 deposit subtypes in Down's syndrome

The spatial patterns of diffuse, primitive and classic β/A4 deposits were studied in coronal sections of the hippocampus and adjacent gyri in 11 cases of Down's syndrome (DS) varying in age from 38 to 67 years. The objectives of the study were first, to compare the spatial patterns of β/A4 deposits revealed in DS with those reported in cases of Alzheimer's disease (AD) and second, to study how the spatial patterns of β/A4 deposits may develop in the tissue. The spatial patterns revealed in DS exhibited a number of similarities with those reported in AD: (1) the range and frequency of the different types of spatial pattern revealed were similar, (2) β/A4 deposits occurred in clusters and in many cortical tissues, the clusters were distributed in a regular pattern parallel to the pia, (3) the clusters of diffuse and primitive β/A4 deposits occurred in an alternating pattern along the cortex, and (4) the clusters of classic β/A4 deposits were not correlated with the clusters of the diffuse and primitive deposits. Primitive deposits may develop from the diffuse deposits in regions of the cortex where extracellular paired helical filaments were formed. However, clusters of the classic β/A4 deposits, which are formed in older cases, appear to develop independently of the diffuse and primitive deposits. © 1994 Springer-Verlag.