515
RESTRICTION ENYZME SCREENING FOR CODON 200 MUTATION INSCRAPIEAMYLOID PRECURSOR PROTEIN GENE IN FOCAL AND EXTRAFOCAL CJD PATIENTS, RELATIVES, AND UNRELATED PEOPLE IN SLOVAKIA
.
I
*Includes 5 familial tlncludes 1 familial tNone tested
cases
(3 families)
case.
Although the mutation occurred in all tested cases within both clusters, it was also found in several healthy relatives over the age of 60 (including the 75-year-old mother of 1 case). The unusually high incidence of CJD in these regions seems to be of recent origin since investigation of medical records and interrogation of the local population has not identified any probable or suspect cases before 1970.’The conjunction of these two observations provides a unique opportunity to examine susceptibility to and causation of CJD since the mutation appears to be a necessary but not sufficient factor in the disease clusters, and invites speculation about an environmental cofactor. We are now doing detailed classical genetic and epidemiological investigations of the cluster populations, focusing on genetic susceptibility to exogenous sources of infection such as scrapie-infected sheep, which are known to exist at least in the Orava focus. Laboratory of CNS Studies, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland 20892, USA
LEV G. GOLDFARB
Research Institute of Preventive Medicine, Bratislava, Czechoslovakia
EVA MITROVÁ
PAUL BROWN BAN HOCK TOH D. CARLETON GAJDUSEK
Laboratory of CNS Studies, NINDS, Bethesda
1. Goldgaber D, Goldfarb LG, Brown P, et al. Mutations m familial Creutzfeldt-Jakob disease and Gerstmann-Straussler syndrome. Exp Neurol 1989; 106: 204-06. 2. Mitrová E. Analytical epidemiology and nsk factors of CJD. In: Court LA, Dormont D, Brown P, Kingsbury DT, eds. Unconventional virus diseases of the central nervous system. Paris: Commissariat à l’Energie Atomique, Service de Documentation, 1990: 19-29. 3. Brown P, Cathala F, Raubertas R, et al. The epidemiology of Creutzfeldt-Jakob disease: conclusion of a 15 year investigation in France, and review of the world literature. Neurology 1987; 37: 895-904.
confirmation of
Immunocytochemical protein
prion
SIR,-Prion disease is a name proposed for the human spongiform encephalopathies (Creutzfeldt-Jakob disease [CJD], GerstmannStraussler syndrome [GSS], kuru). Prion disease is transmissible and is characterised by the presence of an aberrant isoform of a normal cell protein, prion protein, in infected brain tissue.1 The disease is usually characterised by grey-matter spongy degeneration, neuronal loss, and astrocytosis.2 Dr Collinge and colleagues (July 6, p 7) describe a patient with presenile dementia (intellectual decline at 27 years, death at 36 years) who, except for early age at onset, met accepted criteria for Alzheimer’s disease. Analysis of the prion protein gene revealed the case to be a variant of GSS. However, extensive histological examination revealed no characteristic neuropathological features. We have examined this case immunocytochemically. 20 urn sections
of cerebellum and cortex were dewaxed and immunostained with antisera to the abnormal isoform of prion protein (courtesy of J. Hope, AFRC and MRC Neuropathogenesis Unit, Edinburgh) and the peroxidase/anti-peroxidase method.3 This staining revealed definite immunoreactivity in the Purkinje cells of the cerebellum (figure) and in some neurons of the
Purkinje cells in cerebellar cortex (arrows) immunostained with antisera to abnormal isoform of prion protein. (Reduced to half of
x
520.)
superficial laminae of the cortex, indicating the aberrant isoform of prion protein. This immunoreactivity was detectable despite the absence of overt lesions. Polyclonal antibodies against hamster and mouse PrP 27-30 have been used to localise prion protein in normal and scrapie-infected mouse and hamster brain and in CJD-infected mouse brain. These antibodies have yielded positive staining of the plaques in brain tissue from patients with CJD, kuru, GSS, and iatrogenic CJD. However, in normal human brain and Alzheimer brain tissue no staining was found.3.4 These results indicate that the pathogenesis of prion dementia renders either the normally expressed prion protein or the abnormal isoform detectable by immunocytochemistry. Our findings confirm the results of the genetic analysis and support the use of immunocytochemistry to detect the abnormal isoform of prion protein. A combined genetic and immunocytochemical approach should improve diagnostic accuracy in detecting prion disease and simplify the confusing plethora of labels that have evolved; and this in turn, as your July 6 editorial notes, should throw light on the true incidence of the disease. Department of Anatomy and Cell Biology, St Mary’s Hospital Medical School, London
J. CLINTON
Department of Neuropathology, Institute of Psychiatry, London
P. L. LANTOS
Alzheimer’s Disease Research Group, St Mary’s Hospital Medical School
M. ROSSOR M. MULLAN
Department of Anatomy and Cell Biology, St Mary’s Hospital Medical School, London W2 1PG, UK
G. W. ROBERTS
Westaway D, Carlson GA, Prusiner SB, et al. Unravelling prion diseases through molecular genetics. TINS 1989; 12: 221-27. 2. Beck E, Daniel PM. Neuropathology of transmissible spongiform encephalopathies. In: Prusmer SB, Mckinley MP, eds. Prions: novel infectious pathogens causing scrapie and Creutzfeldt-Jakob disease. San Diego: Academic Press, 1987: 331-83. 3. Roberts GW, Lofthouse R, Allsop D, et al. CNS amyloid proteins in neurodegenerative diseases. Neurology 1988; 38: 1534-40. 4. Piccardo P, Safar J, Ceroni M, et al. Immunocytochemical localization or prion protein in spongiform encephalopathies and normal brain. Neurology 1990, 40: 518-22. 1.
Dementia with &bgr;-amyloid deposition: involvement of &agr;B-crystallin supports two main diseases SiR,—Two of us (J. L., R. J. M.) were invited to attend a meeting of the US National Institute of Aging, in Washington in April, 1990, to reassess the neuropathology of Alzheimer’s disease (AD) and other dementias of old age. The meeting was important since, perhaps surprisingly, it reached a consensus on new neuropathological diagnostic criteria for the dementias. These criteria draw extensively on experience from the US Consortium to
RESTRICTION ENYZME SCREENING FOR CODON 200 MUTATION INSCRAPIEAMYLOID PRECURSOR PROTEIN GENE IN FOCAL AND EXTRAFOCAL CJD PATIENTS, RELATIVES, AND UNRELATED PEOPLE IN SLOVAKIA
.
I
*Includes 5 familial tlncludes 1 familial tNone tested
cases
(3 families)
case.
Although the mutation occurred in all tested cases within both clusters, it was also found in several healthy relatives over the age of 60 (including the 75-year-old mother of 1 case). The unusually high incidence of CJD in these regions seems to be of recent origin since investigation of medical records and interrogation of the local population has not identified any probable or suspect cases before 1970.’The conjunction of these two observations provides a unique opportunity to examine susceptibility to and causation of CJD since the mutation appears to be a necessary but not sufficient factor in the disease clusters, and invites speculation about an environmental cofactor. We are now doing detailed classical genetic and epidemiological investigations of the cluster populations, focusing on genetic susceptibility to exogenous sources of infection such as scrapie-infected sheep, which are known to exist at least in the Orava focus. Laboratory of CNS Studies, National Institute of Neurological Disorders and Stroke, Bethesda, Maryland 20892, USA
LEV G. GOLDFARB
Research Institute of Preventive Medicine, Bratislava, Czechoslovakia
EVA MITROVÁ
PAUL BROWN BAN HOCK TOH D. CARLETON GAJDUSEK
Laboratory of CNS Studies, NINDS, Bethesda
1. Goldgaber D, Goldfarb LG, Brown P, et al. Mutations m familial Creutzfeldt-Jakob disease and Gerstmann-Straussler syndrome. Exp Neurol 1989; 106: 204-06. 2. Mitrová E. Analytical epidemiology and nsk factors of CJD. In: Court LA, Dormont D, Brown P, Kingsbury DT, eds. Unconventional virus diseases of the central nervous system. Paris: Commissariat à l’Energie Atomique, Service de Documentation, 1990: 19-29. 3. Brown P, Cathala F, Raubertas R, et al. The epidemiology of Creutzfeldt-Jakob disease: conclusion of a 15 year investigation in France, and review of the world literature. Neurology 1987; 37: 895-904.
confirmation of
Immunocytochemical protein
prion
SIR,-Prion disease is a name proposed for the human spongiform encephalopathies (Creutzfeldt-Jakob disease [CJD], GerstmannStraussler syndrome [GSS], kuru). Prion disease is transmissible and is characterised by the presence of an aberrant isoform of a normal cell protein, prion protein, in infected brain tissue.1 The disease is usually characterised by grey-matter spongy degeneration, neuronal loss, and astrocytosis.2 Dr Collinge and colleagues (July 6, p 7) describe a patient with presenile dementia (intellectual decline at 27 years, death at 36 years) who, except for early age at onset, met accepted criteria for Alzheimer’s disease. Analysis of the prion protein gene revealed the case to be a variant of GSS. However, extensive histological examination revealed no characteristic neuropathological features. We have examined this case immunocytochemically. 20 urn sections
of cerebellum and cortex were dewaxed and immunostained with antisera to the abnormal isoform of prion protein (courtesy of J. Hope, AFRC and MRC Neuropathogenesis Unit, Edinburgh) and the peroxidase/anti-peroxidase method.3 This staining revealed definite immunoreactivity in the Purkinje cells of the cerebellum (figure) and in some neurons of the
Purkinje cells in cerebellar cortex (arrows) immunostained with antisera to abnormal isoform of prion protein. (Reduced to half of
x
520.)
superficial laminae of the cortex, indicating the aberrant isoform of prion protein. This immunoreactivity was detectable despite the absence of overt lesions. Polyclonal antibodies against hamster and mouse PrP 27-30 have been used to localise prion protein in normal and scrapie-infected mouse and hamster brain and in CJD-infected mouse brain. These antibodies have yielded positive staining of the plaques in brain tissue from patients with CJD, kuru, GSS, and iatrogenic CJD. However, in normal human brain and Alzheimer brain tissue no staining was found.3.4 These results indicate that the pathogenesis of prion dementia renders either the normally expressed prion protein or the abnormal isoform detectable by immunocytochemistry. Our findings confirm the results of the genetic analysis and support the use of immunocytochemistry to detect the abnormal isoform of prion protein. A combined genetic and immunocytochemical approach should improve diagnostic accuracy in detecting prion disease and simplify the confusing plethora of labels that have evolved; and this in turn, as your July 6 editorial notes, should throw light on the true incidence of the disease. Department of Anatomy and Cell Biology, St Mary’s Hospital Medical School, London
J. CLINTON
Department of Neuropathology, Institute of Psychiatry, London
P. L. LANTOS
Alzheimer’s Disease Research Group, St Mary’s Hospital Medical School
M. ROSSOR M. MULLAN
Department of Anatomy and Cell Biology, St Mary’s Hospital Medical School, London W2 1PG, UK
G. W. ROBERTS
Westaway D, Carlson GA, Prusiner SB, et al. Unravelling prion diseases through molecular genetics. TINS 1989; 12: 221-27. 2. Beck E, Daniel PM. Neuropathology of transmissible spongiform encephalopathies. In: Prusmer SB, Mckinley MP, eds. Prions: novel infectious pathogens causing scrapie and Creutzfeldt-Jakob disease. San Diego: Academic Press, 1987: 331-83. 3. Roberts GW, Lofthouse R, Allsop D, et al. CNS amyloid proteins in neurodegenerative diseases. Neurology 1988; 38: 1534-40. 4. Piccardo P, Safar J, Ceroni M, et al. Immunocytochemical localization or prion protein in spongiform encephalopathies and normal brain. Neurology 1990, 40: 518-22. 1.
Dementia with &bgr;-amyloid deposition: involvement of &agr;B-crystallin supports two main diseases SiR,—Two of us (J. L., R. J. M.) were invited to attend a meeting of the US National Institute of Aging, in Washington in April, 1990, to reassess the neuropathology of Alzheimer’s disease (AD) and other dementias of old age. The meeting was important since, perhaps surprisingly, it reached a consensus on new neuropathological diagnostic criteria for the dementias. These criteria draw extensively on experience from the US Consortium to
