Inflammatory markers in AD and MCI patients with different biomarker profiles.
OBJECTIVE
The aim of this study was to demonstrate the involvement of the inflammatory proteins IL-6, ACT and CRP early in the pathology process of AD in patients with mild cognitive impairment (MCI) and AD.


METHODS
IL-6, ACT, CRP, Abeta42, phospho-tau (p-tau) and total tau concentrations in serum and CSF of 145 patients with probable AD and 67 patients with MCI were measured by sandwich ELISA. MCI patients were characterized as high- respectively low-risk MCI according to their Abeta42/tau risk profile.


RESULTS
CSF and serum CRP levels were significantly higher in MCI compared to AD patients after adjustment for age, ApoE epsilon4 genotype and cardiovascular diseases (p<0.01). This difference remained present in patients with a low-risk biomarker profile for AD after adjustment for abovementioned covariates. CSF IL-6 levels were also significantly higher in MCI patients with a low-risk CSF profile.


CONCLUSIONS
These findings suggest that inflammatory processes might be involved in early stages of AD, even before Abeta and tau changes are present in CSF of MCI patients.
Schuitemaker
Alie
A
Department of Neurology/Alzheimer Center, VU University Medical Center, 1007 MB Amsterdam, The Netherlands. a.schuitemaker@vumc.nl
Dik
Miranda G
MG
Veerhuis
Robert
R
Scheltens
Philip
P
Schoonenboom
Niki S M
NS
Hack
C Erik
CE
Blankenstein
Marinus A
MA
Jonker
Cees
C
D000368:Aged; D000544:Alzheimer Disease / Q000097:blood / Q000134:cerebrospinal fluid / Q000150:complications; D016229:Amyloid beta-Peptides / Q000378:metabolism; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood / Q000134:cerebrospinal fluid; D002097:C-Reactive Protein / Q000378:metabolism; D003072:Cognition Disorders / Q000097:blood / Q000134:cerebrospinal fluid / Q000150:complications; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000378:metabolism; D012189:Retrospective Studies; D000515:alpha 1-Antitrypsin / Q000378:metabolism; D016875:tau Proteins / Q000378:metabolism
D016229:Amyloid beta-Peptides; D015415:Biomarkers; D015850:Interleukin-6; D010446:Peptide Fragments; D000515:alpha 1-Antitrypsin; C075222:amyloid beta-protein (1-42); D016875:tau Proteins; D002097:C-Reactive Protein