Activation of the classical complement pathway in brain tissue of Alzheimer patients.
Positive immunohistochemical staining of Alzheimer brain tissue was obtained with antibodies to proteins associated with classical, but not the alternative, complement pathway. Clq, C3d, C4d are fractions of complement proteins that bind to tissue when the classical complement pathway is activated. Antibodies to these fractions stained senile plaques, dystrophic neurites and some neurofibrillary tangles. C5b-9 is the membrane attack complex which promotes cell lysis when assembled on the plasma membrane. An antibody to a neoantigenic site on this complex stained dystrophic neurites and many neurofibrillary tangles, but not extracellular amyloid. Properdin and fraction Bb of factor B, two proteins that bind to tissue when the alternative complement pathway is activated, were not detected immunohistochemically.
McGeer
P L
PL
University of British Columbia, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.
Akiyama
H
H
Itagaki
S
S
McGeer
E G
EG
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000276:immunology* / Q000473:pathology; D001921:Brain / Q000276:immunology* / Q000473:pathology; D003167:Complement Activation / Q000276:immunology*; D015922:Complement C1q / Q000378:metabolism; D015933:Complement C3d / Q000378:metabolism; D003181:Complement C4 / Q000378:metabolism; D015935:Complement C4b; D015938:Complement Membrane Attack Complex / Q000378:metabolism; D003171:Complement Pathway, Classical / Q000276:immunology*; D006801:Humans; D007150:Immunohistochemistry; D002479:Inclusion Bodies / Q000473:pathology; D009454:Neurofibrils / Q000473:pathology; D010446:Peptide Fragments / Q000378:metabolism
D003181:Complement C4; D015938:Complement Membrane Attack Complex; D010446:Peptide Fragments; D015922:Complement C1q; D015933:Complement C3d; D015935:Complement C4b; C032261:complement C4d