Complement C1q and C3 mRNA expression in the frontal cortex of Alzheimer's patients

J Mol Med (Berl). 1995 Sep;73(9):465-71. doi: 10.1007/BF00202265.


The levels and cellular localization of mRNA for complement C1q and C3 were examined by RNA gel blot and nonradioactive in situ hybridization in the frontal cortex of patients with Alzheimer's disease (AD) and age-matched controls. We found that the hybridization signal for C1q mRNA was markedly increased (approx. 3.5-fold) in the frontal cortex of AD patients compared to that in age-matched controls. In contrast to previous reports we also found that the levels of C3 mRNA, although well expressed, did not differ significantly between AD cases and age-matched controls. Nonradioactive in situ hybridization using digoxigenin-labeled ribo-probes revealed that transcripts coding for both C1q and C3 were closely associated with neurons. These results support the hypothesis that complement could play a role in neuronal degeneration which has been observed in the brain of AD patients.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / metabolism*
  • Blotting, Northern
  • Complement C1q / biosynthesis*
  • Complement C3 / biosynthesis*
  • Female
  • Frontal Lobe / metabolism*
  • Gene Expression*
  • Humans
  • In Situ Hybridization
  • Male
  • Middle Aged
  • RNA, Messenger / analysis
  • RNA, Messenger / biosynthesis*
  • Reference Values


  • Complement C3
  • RNA, Messenger
  • Complement C1q