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7 Tau and Ubiquitin as diagnostic markers of Alzheimer disease
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FIFTH INTERNATIONAL CONFERENCE ON ALZHEIMER'S DISEASE
neuron-specific enolase (NSE) and neuromodulin (NM, GAP43 or B50) in CSF. NSE and tau CSF levels were measured in a group of Alzheimer patients (n=22) and patients with OND (n=52).NSE levels did not differ signicantly between AD and OND patients (6.5 + 2.3 for AD versus 6.8 ± 1.8 ng/ml for OND). However, tau levels were significantly higher in the AD group (AD: 334±129 vs OND: 183::1:79 pglml). Moreover, a highly significant correlation between tau and NSE levels (p < 0.0001) occurred in the Alzheimer group only, indicating that both markers reflect the same pathological event. These results were further confirmed when NM levels were compared with tan and phospho-tau in a group of Alzheimer patients (n=44) and welldefined age-matched controls (n=31). A significant difference in NM was found between AD and controls (AD:56±39 aribitrary units (AU) vs controls: 21 + 19 AU), but not to the same extent as tau (AD:571 ±263 vs controls: 207±79 pg/ml) or phospho-tau (AD: 2690±294 vs controls: 620±294). Again, a highly significant relationship was found between NM and tau/phospho-tau in the Alzheimer patients only. The correlation between elevated levels of tau/phospho-tau and other intracellular proteins, increased in the CSF of AD patients, can therefor improve the specificity of tests for AD.
kDa±l). A fourth Tau variant of 72 kDa is also frequent in severely affected AID patients. PHF-Tan isoelectd¢ points for AD patients are more acidic than normal Tau proteins. During normal aging, PHF-Tau are always found in the hippecampal region from controls cases aged over 75, but are restricmd to this brain region (transentorhinal, entorhinal cortex and hippocampns). In nondemented patients in a preclinical state of AD (CDR=0.5 and numerous amyloid deposits in the isocortex), PHF-Tau are detected in the hippocampal area as well as in the anterior, inferior and medium temporal cortex. This indicates that PHF-Tau are produced in large amounts before the expression of dementia and thus has implicationsfor an early biological diagnosis of AD. Using the same approach, we found that the electrophoretic Tan profile in progressive supranuclear palsy and corticobasal degeneration was different and composed of a Tan doublet (Tau 64 and 69). Another type of Tan doublet (Tau 55 and 64), less phosphorylated than the AD Tan triplet, is systematically found in the fronto-temporalbrain regions from patients with Pick's disease. Together, these data show that the presence of pathological Tan proteins in the isocortex is extremely well correlated to dementia and reveal the possibilities as well as the difficulties to establish a specific biological antemortem diagnosisof AD.
5 The importance of tile localization of the biochemical markers in Alzheimer disease. C. Duyckaerts*, T. Uchihara, Y.He, M. Benecib, J.J Hauw. Laboratoire de NeuropathologieEsceurelle, La Salp~tri~re, Paris, France. The topography of tau- and amyloid markers were studied post-mortem in thirty cases over 75 years of age, that had been prospectively assessed by the Blessed test score (BTS). The relationship with apoE immunohistochemistry and microglial markers were analyzed in selected areas. The samples included limbic (subiculum), and paralimbic (parahippocampal gyros-PriG) cortices, multi- (area 40) and uni-modal ( area 22) associative areas, as well as a primary sensory cortex (area 17). The BTS accurately predicted the presence of neurefibrillary tangle, but with a threshold which varied according to the area : area 17 (primary visual area) was most often untouched, exhibiting NFT only in those cases with the most severe intellectual deficit (BTS<4). The clinical thresholds were of similar values in the associative cortices (BTS<16 for area 22, BTS<15 for the supramarginal gyrus; BTS<14 for area 8). There was no clinical threshold in the paralimbic areas : NFT were observed even in cases that were considered normal. The number of regions in which there was at least one NFT (whatever the density) was used as a diffusion index (minimal value 0; maximal value: 6 in this study). This 'diffusion index' was highly correlated with the intellectual status (r=0.879; p<0.0001), around 5 digits of the BTS being lost for each lesioned area. There was a strong relationship between tau positive NFT and tan positive (neuritic) senile plaques (NSP) : in a given area, the densities of NSP and of NFT were always correlated with no threshold. There was 0.53 SP for 1 NFT in area 17; 0.26 in area 22; 0.15 in area 8; 0.14 in PHG; 0.10 in the subiculum; 0.081 in area 40. A significant correlation between the densities of NSP and of AI3 diffuse deposits (DD) was found in the subiculum, PHG, and area 17 but was lacking in areas 8, 22, 40. The presence of microglial markers and of ApoE focal deposit in the SP was linked to the presence of neurites. These findings show that AB peptide is a less sensitive and a less specific marker of dementia tau positive neuritic alterations. The topography of these alterations in the cortex is a better indication of AD than their mere presence. The 'diffusion index' confirms the progression &the disease as described by Braak and Braak.
7 Tan and Ubiquitin as Diagnostic Markers of Alzheimer Disease I. Gvundke-Iqbal', T. Kudo, S. Khatoon, Q. Wu and IC Iqbal New York State Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, New York 10314, USA One of the most characteristic brain lesions of Alzheimer disease is the accumulation of paired helical filaments (PHF) in the affected neurons. The PHF are prominent in all the three major disease lesions, namely the neurofibrillary tangles, the neuropil threads and the neuritic (senile) plaques. The microtubule associated protein tan in abnormally byperphosphorylated form is the major protein subunit of the PHF (Grundke-Iqbal et al., J. Biol. Chem. 226, 6084-6089, 1986; Proc. Natl Acad. Sci. U.S.A. 83:4913-4917, 1996). The abnormal hyperphosphorylation oftau apparently precedes the formation of PHF and the association with ubiqnitin (Iqbal et al. Lancet, 2:421-426, 1986; Bancher et al. Brain Res. 477:90-00, 1986; Kbpke et al. J. Biol. Chem. 268:24374-24384, 1993). The association of ubiquitin with PHF is seen mostly in mature intrancuronal neurofibrillary tangles and the ghost tangles. The levels of tau and ubiquitin are increased in both the brain (Khatoon et al. J. Neurochem. 59:750-753, 1992; FEBS Lett. 531:80-84, 1994; Kudo et al. Brain Res. 639:17, 1994; Wang, et al. Brain Res. 566:146-151, 1991) and CSF (Wang et al. Acta Neuropathol. 8:6-12, 1991; Kudo, et al. Brain Res. 639:1-7, 1994) of patients with AD. However, for these two proteins, and for that matter any other proteins to be a useful diagnostic tool for therapeutic trials, (a) changes in the protein levels should be detectable at a very early stage of the disease, preferably prior to the onset of the symptoms and (b) the levels should correlate to the progression of the disease. (Supported in part by NY State Office of Mental Retardation and Developmental Disabilities, NIH grants NS18105, AG05892, AG08076, AG04220, and a Zenith Award from the Alzheimer's Association, Chicago).
8 6 Pathological Tau proteins are biochemical markers that differentiate several types of neuroflbrillary degeneration. A. Delacourte, N. Sergeant, V. Bu6e-Scherrer, L. Bu6e, J-P. David, T. Bussi&e, P. Vermersch, A. Wattez. Unit6 INSERM 422, PlaceVerdun, 59045 Lille cedex France. Fax 33/20.62.20.79 Paired Helical Filaments (PHF) of Alzheimer's disease (AD) are constituted of several Tau variants which are in an hyperphosphorylated state, as demonstrated with 2D gel immunoblot analysis. PHF-Tau are composed of a triplet of Tau variants named Tan 55, 64, 69 (calculated MW of 55, 60 and 65
Acetylcholinesteruse in cerebrospinal fluid in relation to histopathological diagnosis of Alzheimer's disease and apolipoproteln E allelotype A.D. Smith*, C. Johnston, Z.X. Shen, K.A. Jobst, N. Hindley, E. King, Zs. Nagy, M.M. Esiri, C. Joachim, B. McDonald, L. Bametson and L. Sutton OPTIMA, Department of Pharmacology, Mansfield Rd., Oxford OX1 3QT There is no consensus in studies on acetylcholinesterase (ACHE) activity in cerebrospinal fluid (CSF) in clinically diagnosed dementia of Alzheimer's type (DAT). The first report (Appleyard et 8.1.Lancet 1983, ii, 452) on subjects with a histopathological diagnosis of Alzheimer's disease (AD) showed a 62% lower level of AChE activity in venWicular CSF taken at necropsy in AD compared with controls. However, in 6 subjects who had a histopathological diagnosis of AD by biopsy there was no difference in AChE levels in lumbar CSF taken during life (Appleyard et al. Brain 1987, ll0, 1309). An anomalous isoenzyme
FIFTH INTERNATIONAL CONFERENCE ON ALZHEIMER'S DISEASE
neuron-specific enolase (NSE) and neuromodulin (NM, GAP43 or B50) in CSF. NSE and tau CSF levels were measured in a group of Alzheimer patients (n=22) and patients with OND (n=52).NSE levels did not differ signicantly between AD and OND patients (6.5 + 2.3 for AD versus 6.8 ± 1.8 ng/ml for OND). However, tau levels were significantly higher in the AD group (AD: 334±129 vs OND: 183::1:79 pglml). Moreover, a highly significant correlation between tau and NSE levels (p < 0.0001) occurred in the Alzheimer group only, indicating that both markers reflect the same pathological event. These results were further confirmed when NM levels were compared with tan and phospho-tau in a group of Alzheimer patients (n=44) and welldefined age-matched controls (n=31). A significant difference in NM was found between AD and controls (AD:56±39 aribitrary units (AU) vs controls: 21 + 19 AU), but not to the same extent as tau (AD:571 ±263 vs controls: 207±79 pg/ml) or phospho-tau (AD: 2690±294 vs controls: 620±294). Again, a highly significant relationship was found between NM and tau/phospho-tau in the Alzheimer patients only. The correlation between elevated levels of tau/phospho-tau and other intracellular proteins, increased in the CSF of AD patients, can therefor improve the specificity of tests for AD.
kDa±l). A fourth Tau variant of 72 kDa is also frequent in severely affected AID patients. PHF-Tan isoelectd¢ points for AD patients are more acidic than normal Tau proteins. During normal aging, PHF-Tau are always found in the hippecampal region from controls cases aged over 75, but are restricmd to this brain region (transentorhinal, entorhinal cortex and hippocampns). In nondemented patients in a preclinical state of AD (CDR=0.5 and numerous amyloid deposits in the isocortex), PHF-Tau are detected in the hippocampal area as well as in the anterior, inferior and medium temporal cortex. This indicates that PHF-Tau are produced in large amounts before the expression of dementia and thus has implicationsfor an early biological diagnosis of AD. Using the same approach, we found that the electrophoretic Tan profile in progressive supranuclear palsy and corticobasal degeneration was different and composed of a Tan doublet (Tau 64 and 69). Another type of Tan doublet (Tau 55 and 64), less phosphorylated than the AD Tan triplet, is systematically found in the fronto-temporalbrain regions from patients with Pick's disease. Together, these data show that the presence of pathological Tan proteins in the isocortex is extremely well correlated to dementia and reveal the possibilities as well as the difficulties to establish a specific biological antemortem diagnosisof AD.
5 The importance of tile localization of the biochemical markers in Alzheimer disease. C. Duyckaerts*, T. Uchihara, Y.He, M. Benecib, J.J Hauw. Laboratoire de NeuropathologieEsceurelle, La Salp~tri~re, Paris, France. The topography of tau- and amyloid markers were studied post-mortem in thirty cases over 75 years of age, that had been prospectively assessed by the Blessed test score (BTS). The relationship with apoE immunohistochemistry and microglial markers were analyzed in selected areas. The samples included limbic (subiculum), and paralimbic (parahippocampal gyros-PriG) cortices, multi- (area 40) and uni-modal ( area 22) associative areas, as well as a primary sensory cortex (area 17). The BTS accurately predicted the presence of neurefibrillary tangle, but with a threshold which varied according to the area : area 17 (primary visual area) was most often untouched, exhibiting NFT only in those cases with the most severe intellectual deficit (BTS<4). The clinical thresholds were of similar values in the associative cortices (BTS<16 for area 22, BTS<15 for the supramarginal gyrus; BTS<14 for area 8). There was no clinical threshold in the paralimbic areas : NFT were observed even in cases that were considered normal. The number of regions in which there was at least one NFT (whatever the density) was used as a diffusion index (minimal value 0; maximal value: 6 in this study). This 'diffusion index' was highly correlated with the intellectual status (r=0.879; p<0.0001), around 5 digits of the BTS being lost for each lesioned area. There was a strong relationship between tau positive NFT and tan positive (neuritic) senile plaques (NSP) : in a given area, the densities of NSP and of NFT were always correlated with no threshold. There was 0.53 SP for 1 NFT in area 17; 0.26 in area 22; 0.15 in area 8; 0.14 in PHG; 0.10 in the subiculum; 0.081 in area 40. A significant correlation between the densities of NSP and of AI3 diffuse deposits (DD) was found in the subiculum, PHG, and area 17 but was lacking in areas 8, 22, 40. The presence of microglial markers and of ApoE focal deposit in the SP was linked to the presence of neurites. These findings show that AB peptide is a less sensitive and a less specific marker of dementia tau positive neuritic alterations. The topography of these alterations in the cortex is a better indication of AD than their mere presence. The 'diffusion index' confirms the progression &the disease as described by Braak and Braak.
7 Tan and Ubiquitin as Diagnostic Markers of Alzheimer Disease I. Gvundke-Iqbal', T. Kudo, S. Khatoon, Q. Wu and IC Iqbal New York State Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, New York 10314, USA One of the most characteristic brain lesions of Alzheimer disease is the accumulation of paired helical filaments (PHF) in the affected neurons. The PHF are prominent in all the three major disease lesions, namely the neurofibrillary tangles, the neuropil threads and the neuritic (senile) plaques. The microtubule associated protein tan in abnormally byperphosphorylated form is the major protein subunit of the PHF (Grundke-Iqbal et al., J. Biol. Chem. 226, 6084-6089, 1986; Proc. Natl Acad. Sci. U.S.A. 83:4913-4917, 1996). The abnormal hyperphosphorylation oftau apparently precedes the formation of PHF and the association with ubiqnitin (Iqbal et al. Lancet, 2:421-426, 1986; Bancher et al. Brain Res. 477:90-00, 1986; Kbpke et al. J. Biol. Chem. 268:24374-24384, 1993). The association of ubiquitin with PHF is seen mostly in mature intrancuronal neurofibrillary tangles and the ghost tangles. The levels of tau and ubiquitin are increased in both the brain (Khatoon et al. J. Neurochem. 59:750-753, 1992; FEBS Lett. 531:80-84, 1994; Kudo et al. Brain Res. 639:17, 1994; Wang, et al. Brain Res. 566:146-151, 1991) and CSF (Wang et al. Acta Neuropathol. 8:6-12, 1991; Kudo, et al. Brain Res. 639:1-7, 1994) of patients with AD. However, for these two proteins, and for that matter any other proteins to be a useful diagnostic tool for therapeutic trials, (a) changes in the protein levels should be detectable at a very early stage of the disease, preferably prior to the onset of the symptoms and (b) the levels should correlate to the progression of the disease. (Supported in part by NY State Office of Mental Retardation and Developmental Disabilities, NIH grants NS18105, AG05892, AG08076, AG04220, and a Zenith Award from the Alzheimer's Association, Chicago).
8 6 Pathological Tau proteins are biochemical markers that differentiate several types of neuroflbrillary degeneration. A. Delacourte, N. Sergeant, V. Bu6e-Scherrer, L. Bu6e, J-P. David, T. Bussi&e, P. Vermersch, A. Wattez. Unit6 INSERM 422, PlaceVerdun, 59045 Lille cedex France. Fax 33/20.62.20.79 Paired Helical Filaments (PHF) of Alzheimer's disease (AD) are constituted of several Tau variants which are in an hyperphosphorylated state, as demonstrated with 2D gel immunoblot analysis. PHF-Tau are composed of a triplet of Tau variants named Tan 55, 64, 69 (calculated MW of 55, 60 and 65
Acetylcholinesteruse in cerebrospinal fluid in relation to histopathological diagnosis of Alzheimer's disease and apolipoproteln E allelotype A.D. Smith*, C. Johnston, Z.X. Shen, K.A. Jobst, N. Hindley, E. King, Zs. Nagy, M.M. Esiri, C. Joachim, B. McDonald, L. Bametson and L. Sutton OPTIMA, Department of Pharmacology, Mansfield Rd., Oxford OX1 3QT There is no consensus in studies on acetylcholinesterase (ACHE) activity in cerebrospinal fluid (CSF) in clinically diagnosed dementia of Alzheimer's type (DAT). The first report (Appleyard et 8.1.Lancet 1983, ii, 452) on subjects with a histopathological diagnosis of Alzheimer's disease (AD) showed a 62% lower level of AChE activity in venWicular CSF taken at necropsy in AD compared with controls. However, in 6 subjects who had a histopathological diagnosis of AD by biopsy there was no difference in AChE levels in lumbar CSF taken during life (Appleyard et al. Brain 1987, ll0, 1309). An anomalous isoenzyme