350 Brain Research, 579 (1992) 350-352 © 1992 Elsevier Science Publishers B.V. All rights reserved. 0006-8993/92/$05.00 BRES 25166 Basic fibroblast growth factor binds to filamentous inclusions of neurodegenerative diseases George Perry, Peggy Richey, Sandra L. Siedlak, Pamela Galloway, Mitsuru Kawai and Patrick Cras Division of Neuropathology, Institute of Pathology, Case Western Reserve University, Cleveland, OH 44106-4901 (USA) (Accepted 29 January 1992) Key words: Alzheimer disease; Heparan sulfate proteoglycan; Pick disease; Parkinson disease: Progressive supranuclear palsy; Diffuse Lewy body disease The extracellular matrix protein heparan sulfate proteoglycans (HSPG) has been found in the neurofibrillary pathology of Alzheimer dis- ease. This study was performed to determine if similar proteoglycans might be present in the fibrillary inclusions of other neurodegenerative diseases. Basic fibroblast growth factor (bFGF) binding to heparinase sensitive sites was used as an assay for HSPGs. We found that the inclusions of Pick and Parkinson diseases as well as progressive supranuclear palsy contained heparinase sensitive bFGF binding sites while the inclusions of diffuse Lewy body disease lacked bFGF binding sites. These findings indicate that HSPG's interactions and possible role in the formation of intraneuronal inclusions are not limited to Alzheimer disease. Insolubility in denaturants has hindered direct deter- mination of the composition of the filamentous neuronal inclusions of Alzheimer disease 9'12, progressive supranu- clear palsy (PSP) 16, Pick disease 11 and Parkinson dis- ease z. Nevertheless intense interest in the origin of the filamentous structures has led to a proliferation of indi- rect approaches primarily utilizing immunochemical methodologies. Immunochemistry has been used to show the involvement of the neuronal cytoskeleton in the for- mation of the filaments 1'2'9't1'16. Complementing these studies has been the isolation of a soluble form of the paired helical filaments characteristic of Alzheimer dis- ease which is analyzable by direct biochemical analysis and composed of the microtubule associated protein r 4'5. Yet, in recent studies a heparan sulfate proteoglycan (HSPGs) has also been reported in the intraneuronal fil- aments of Alzheimer disease 1°A3'14 indicating that the structural rearrangement leading to the neurofibrillary tangles (NFT) may not be restricted to cytoskeletal ele- ments. The present study was undertaken to determine if HSPGs were present in the inclusions of other neuro- degenerative diseases. Sections from the locus coeruleus of 5 cases of idio- pathic Parkinson disease (age 53-70 years) and from the pons of 4 cases of PSP (age 76-83 years) were examined. Frontal and temporal cortex of 3 cases of Pick disease (age 62-68 years) and 3 cases of diffuse Lewy body dis- ease (age 75-82 years) were also examined. All tissue had been fixed in buffered formalin and embedded in paraffin prior to sectioning (6/zm thick). HSPGs were detected by basic fibroblast growth factor (bFGF)which avidly binds to heparinase sensitive sites in NFT of Alz- heimer disease 1°'13. The method, as previously described in detail 13, involves incubating sections with 5 ~g/ml of recombinant human bFGF (Calbio) in 20 mM EDTA, 0.1 M Tris, pH 7.6 for 2 h at 37°C followed by immu- nostaining with a monoclonal antibody to bFGF (48.1, Calbio). Affinity purified antiserum to r s and ubiquitin 7 were used on adjacent sections as an aid in identifying inclusions. Immunostains were developed with the per- oxidase-antiperoxidase procedure 15 with 3'3' diami- nobenzidine as co-substrate. In Pick disease, intraneuronal Pick bodies bound bFGF (Fig. 1A), but extraneuronal round structures were more frequently seen. The extraneuronal structures are consistent with the persistence of Pick bodies in the ex- tracellular space since they are the same size as Pick bodies, occurred in the same regions, are fibrillar and are distinct in distribution from corpora amylacea. In PSP numerous NFT were seen in the pontine nuclei (Fig. 1C). The number of NFT of PSP binding bFGF was far greater than recognized by the antiserum to r or ubiq- uitin and the vast majority were extracellular. In Parkinson disease only some of the Lewy bodies Correspondence." G. Perry, Division of Neuropathology, Institute of Pathology, Case Western Reserve University, 2085 Adelbert Road, Cleveland, OH 44106-4901 USA. Fax: (1)(216) 368-8964.