title: Correlation of the expression level of C1q mRNA and the number of C1q-positive plaques in the Alzheimer Disease temporal cortex. analysis of C1q mrna and its protein using adjacent or nearby sections.
abstract: We compared the expression level of C1q mRNA and the number of C1q-positive plaques in adjacent or nearby brain sections from Alzheimer disease (AD) and control cases. Small blocks of temporal cortex were fixed with 4% paraformaldehyde for 2 days at 4 degrees C. After cryoprotection with solutions containing 10-20% glycerol and 2% dimethylsulfoxide, 40-microm sections were cut from the tissue blocks. A section from each case was stained by immunohistochemistry using a C1q antibody, while RNA was purified from adjacent or nearby sections using a combination of proteinase K pretreatment followed by extraction using Trizol reagent. The expression of C1q B chain mRNA was analyzed in these samples by the reverse-transcription polymerase chain reaction (RT-PCR). The intensities of the PCR products were measured by an image analyzer. The expression of C1q B chain mRNA was significantly more abundant in AD than in control cases (p < 0.05). Immunohistochemical analysis showed that C1q protein was localized in senile plaques in the AD brain. The number of C1q-positive plaques correlated with the expression level of C1q gene (p < 0.05). The present results suggest that C1q protein in senile plaques originates is endogenously produced in the AD brain.
authors.affiliation: Molecular Neuroscience Research Center, Shiga University of Medical Science, Otsu, Japan. kinchan@sums.shiga-med.ac.jp
authors.forename: I
authors.initials: I
authors.lastname: Tooyama
authors.forename: H
authors.initials: H
authors.lastname: Sato
authors.forename: O
authors.initials: O
authors.lastname: Yasuhara
authors.forename: H
authors.initials: H
authors.lastname: Kimura
authors.forename: Y
authors.initials: Y
authors.lastname: Konishi
authors.forename: Y
authors.initials: Y
authors.lastname: Shen
authors.forename: D G
authors.initials: DG
authors.lastname: Walker
authors.forename: T G
authors.initials: TG
authors.lastname: Beach
authors.forename: L I
authors.initials: LI
authors.lastname: Sue
authors.forename: J
authors.initials: J
authors.lastname: Rogers
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D001923:Brain Chemistry; D016022:Case-Control Studies; D015922:Complement C1q / Q000096:biosynthesis* / Q000235:genetics; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D058225:Plaque, Amyloid / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013702:Temporal Lobe / Q000737:chemistry / Q000378:metabolism / Q000473:pathology*
chemical_list: D012333:RNA, Messenger; D015922:Complement C1q