Improved Differential Diagnosis of Alzheimer's Disease by Integrating ELISA and Mass Spectrometry-Based Cerebrospinal Fluid Biomarkers.

Background: Alzheimer's disease (AD) is diagnosed based on a clinical evaluation as well as analyses of classical biomarkers: Aβ42, total tau (t-tau), and phosphorylated tau (p-tau) in cerebrospinal fluid (CSF). Although the sensitivities and specificities of the classical biomarkers are fairly good for detection of AD, there is still a need to develop novel biochemical markers for early detection of AD.

Objective: We explored if integration of novel proteins with classical biomarkers in CSF can better discriminate AD from non-AD subjects.

High tau levels in cerebrospinal fluid predict nursing home placement and rapid progression in Alzheimer's disease.

Background: Increased concentrations of cerebrospinal fluid (CSF) total tau (t-tau) and phosphorylated tau, as well as decreased amyloid-β 42 peptide, are biomarkers of Alzheimer's disease (AD) pathology, but few studies have shown an association with AD progression rate. We hypothesized that high CSF tau, as a marker of ongoing neurodegeneration, would predict a more aggressive course of AD, using time to nursing home placement (NHP) as the main outcome.

Methods: Our sample inlcuded 234 patients with mild cognitive impairment (MCI) due to AD (n = 134) or mild to moderate AD (n = 100) who underwent lumbar puncture at a memory clinic and were followed for 2-11 years (median 4.

Identification of low molecular weight pyroglutamate A{beta} oligomers in Alzheimer disease: a novel tool for therapy and diagnosis.

N-terminally truncated Aβ peptides starting with pyroglutamate (AβpE3) represent a major fraction of all Aβ peptides in the brain of Alzheimer disease (AD) patients. AβpE3 has a higher aggregation propensity and stability and shows increased toxicity compared with full-length Aβ. In the present work, we generated a novel monoclonal antibody (9D5) that selectively recognizes oligomeric assemblies of AβpE3 and studied the potential involvement of oligomeric AβpE3 in vivo using transgenic mouse models as well as human brains from sporadic and familial AD cases.

Higher cathepsin B levels in plasma in Alzheimer's disease compared to healthy controls.

Cathepsin B is suggested to be involved in amyloid-β (Aβ) processing and Alzheimer's disease (AD). Studies of cathepsin B levels in plasma and cerebrospinal fluid (CSF) have not been previously performed. We examined cathepsin B levels in plasma and CSF samples in persons with AD, mild cognitive impairment (MCI), and healthy controls in order to test the hypothesis that cathepsin B levels can discriminate persons with AD or MCI from healthy controls.

Cystatin C levels are positively correlated with both Abeta42 and tau levels in cerebrospinal fluid in persons with Alzheimer's disease, mild cognitive impairment, and healthy controls.

Cystatin C is suggested to be involved in neurodegeneration and the development of Alzheimer's disease (AD) by binding to soluble amyloid-beta (Abeta) peptides. Studies of cystatin C levels in cerebrospinal fluid (CSF) in relation to risk of AD are conflicting and relations between cystatin C, Abeta42, and tau levels in CSF in AD, mild cognitive impairment (MCI), and healthy controls are unknown. The objective of this study was to investigate cystatin C, Abeta42, and tau levels in CSF in AD, MCI, and controls.

CALHM1 P86L polymorphism does not alter amyloid-beta or tau in cerebrospinal fluid.

Recently, the P86L alteration in CALHM1 (calcium homeostasis modulator-1) was reported to be associated with Alzheimer's disease (AD). Moreover, the risk allele increased amyloid-beta (A beta) levels in conditioned media from cultured cells. Therefore, we hypothesized that CALHM1 P86L may modulate A beta or tau levels in cerebrospinal fluid (CSF).

Reduced levels of IgM autoantibodies against N-truncated pyroglutamate Aβ in plasma of patients with Alzheimer's disease.

In the present work, we investigated the level of IgM autoantibodies directed against different Aβ epitopes as potential diagnostic biomarker for Alzheimer's disease (AD). Anti-Aβ autoantibody levels were measured in 75 plasma samples from patients with AD, individuals with mild cognitive impairment (MCI), and healthy age- and sex-matched controls (HC). To validate the presence of anti-Aβ IgMs, pooled plasma samples were subjected to gel-filtration analysis.

Systemic tocopherols and F2-isoprostanes and the risk of Alzheimer's disease and dementia: a prospective population-based study.

Oxidative stress in the brain is suggested to be involved in the pathophysiology of Alzheimer's disease (AD). In this study, serum alpha- and gamma-tocopherol, the two major systemic antioxidants, were analyzed at two examinations of the ULSAM-study, a longitudinal, community-based study of elderly men (age 70, n = 616 and age 77, n = 761). In addition, urinary F2-isoprostane levels, as markers of systemic oxidative stress, were analyzed at the age of 77 in this cohort (n = 679).

Systemic inflammation and the risk of Alzheimer's disease and dementia: a prospective population-based study.

Inflammation is suggested to be involved in the pathogenesis of Alzheimer's disease (AD). Serum interleukin-6 (IL-6) and high sensitivity serum reactive protein C (hsCRP) as markers of systemic inflammation were analyzed at two examinations of the ULSAM-study, a longitudinal, community-based study of elderly men (age 70, n = 1062 and age 77, n = 749). In addition, serum amyloid protein A (SAA) and urinary prostaglandin F2alpha (PGF2alpha) metabolite levels were analyzed at age 77 in this cohort.

Oligomerization partially explains the lowering of Abeta42 in Alzheimer's disease cerebrospinal fluid.

Background/objective: The lowering of natively analyzed Abeta42 in cerebrospinal fluid (CSF) is used as a diagnostic tool in Alzheimer's disease (AD). The presence of Abeta oligomers can interfere with such analyses causing underestimation of Abeta levels due to epitope masking. The aim was to investigate if the lowering of CSF Abeta42 seen in AD is caused by oligomerization.

Circulating immune complexes of Abeta and IgM in plasma of patients with Alzheimer's disease.

It has previously been shown that immune complexes (IC) of a given biomarker with class M immunoglobulins (IgM) provide better performances compared to the unbound biomarker in a number of cancer entities. In the present work, we investigated IC of IgM-Abeta as a potential biomarker for Alzheimer's disease (AD). Abeta-IgM concentration has been measured in 75 plasma samples from patients with AD, individuals with mild cognitive impairment (MCI), and healthy age- and sex-matched controls (HC).

Genetic analysis of Alzheimer's disease in the Uppsala Longitudinal Study of Adult Men.

Background/aims: Genetic factors influencing common complex conditions have proven difficult to identify, and data from numerous investigations have provided incomplete conclusions as to the identity of these genes. Here we aimed to identify susceptibility genes for late-onset Alzheimer's disease (AD).

Methods: The case-control analysis included samples from 86 AD patients and 404 cognitively healthy controls selected from the Uppsala Longitudinal Study of Adult Men (ULSAM).

Plasma beta amyloid and the risk of Alzheimer disease and dementia in elderly men: a prospective, population-based cohort study.

Background: Beta amyloid (Abeta) protein accumulates in the brains of individuals with Alzheimer disease (AD) and is detectable in cerebrospinal fluid and plasma.

Objective: To examine plasma levels of Abeta peptides Abeta(40) and Abeta(42) as predictors of incident AD and other types of dementia.

Design: Prospective, population-based cohort study.