Biosensors,
Journal Year:
2025,
Volume and Issue:
15(2), P. 85 - 85
Published: Feb. 4, 2025
Alzheimer’s
disease
(AD)
is
a
prevalent
neurodegenerative
disorder
and
significant
cause
of
dementia
in
elderly
individuals,
with
growing
prevalence
our
aging
population.
Extracellular
amyloid-β
peptides
(Aβ),
intracellular
tau
proteins,
their
phosphorylated
forms
have
gained
prominence
as
critical
biomarkers
for
early
precise
diagnosis
AD,
correlating
progression
response
to
therapy.
The
high
costs
invasiveness
conventional
diagnostic
methods,
such
positron
emission
tomography
(PET)
magnetic
resonance
imaging
(MRI),
limit
suitability
large-scale
or
routine
screening.
However,
electrochemical
(EC)
analysis
methods
made
progress
detection
due
sensitivity,
excellent
specificity,
portability,
cost-effectiveness.
This
article
reviews
the
EC
biosensing
technologies,
focusing
on
protein
blood
(a
low-invasive,
accessible
medium).
then
discusses
various
sensing
platforms,
including
fabrication
processes,
(LOD),
clinical
potential
show
role
these
sensors
transformers
changing
face
AD
diagnostics.
JAMA,
Journal Year:
2024,
Volume and Issue:
332(15), P. 1245 - 1245
Published: July 28, 2024
Importance
An
accurate
blood
test
for
Alzheimer
disease
(AD)
could
streamline
the
diagnostic
workup
and
treatment
of
AD.
Objective
To
prospectively
evaluate
a
clinically
available
AD
in
primary
care
secondary
using
predefined
biomarker
cutoff
values.
Design,
Setting,
Participants
There
were
1213
patients
undergoing
clinical
evaluation
due
to
cognitive
symptoms
who
examined
between
February
2020
January
2024
Sweden.
The
values
had
been
established
an
independent
cohort
applied
(n
=
307)
300);
1
plasma
sample
per
patient
was
analyzed
as
part
single
batch
each
cohort.
then
evaluated
208)
398);
sent
analysis
within
2
weeks
collection.
Exposure
Blood
tests
based
on
analyses
by
mass
spectrometry
determine
ratio
phosphorylated
tau
217
(p-tau217)
non–p-tau217
(expressed
percentage
p-tau217)
alone
when
combined
with
amyloid-β
42
40
(Aβ42:Aβ40)
(the
amyloid
probability
score
[APS2]).
Main
Outcomes
Measures
outcome
pathology
(determined
abnormal
cerebrospinal
fluid
Aβ42:Aβ40
p-tau217).
positive
predictive
value
(PPV),
negative
(NPV),
accuracy,
area
under
curve
(AUC)
calculated.
Results
mean
age
74.2
years
(SD,
8.3
years),
48%
women,
23%
subjective
decline,
44%
mild
impairment,
33%
dementia.
In
both
assessments,
50%
pathology.
When
samples
cohort,
AUC
0.97
(95%
CI,
0.95-0.99)
APS2
used,
PPV
91%
87%-96%),
NPV
92%
87%-96%);
0.96
0.94-0.98)
88%
83%-93%),
87%
82%-93%).
(biweekly)
81%-94%),
90%
84%-96%);
0.95-0.98)
87%-95%),
87%-95%).
accuracy
high
4
cohorts
(range,
88%-92%).
Primary
physicians
61%
53%-69%)
identifying
after
examination,
testing,
computed
tomographic
scan
vs
86%-96%)
APS2.
Dementia
specialists
73%
68%-79%)
88%-95%)
overall
population,
(90%
[95%
88%-92%])
not
different
from
p-tau217
88%-91%]).
Conclusions
Relevance
among
individuals
Future
studies
should
how
use
these
biomarkers
influences
care.
Nature Reviews Neurology,
Journal Year:
2024,
Volume and Issue:
20(7), P. 426 - 439
Published: June 12, 2024
Anti-amyloid
treatments
for
early
symptomatic
Alzheimer
disease
have
recently
become
clinically
available
in
some
countries,
which
has
greatly
increased
the
need
biomarker
confirmation
of
amyloid
pathology.
Blood
(BBM)
tests
pathology
are
more
acceptable,
accessible
and
scalable
than
PET
or
cerebrospinal
fluid
(CSF)
tests,
but
highly
variable
levels
performance.
The
Global
CEO
Initiative
on
Alzheimer's
Disease
convened
a
BBM
Workgroup
to
consider
minimum
acceptable
performance
clinical
use.
Amyloid
status
was
identified
as
reference
standard.
For
use
triaging
test
before
subsequent
confirmatory
such
CSF
recommends
that
sensitivity
≥90%
with
specificity
≥85%
primary
care
≥75–85%
secondary
depending
availability
follow-up
testing.
without
should
equivalent
—
~90%.
Importantly,
predictive
values
all
vary
according
pre-test
probability
must
be
interpreted
complete
context.
Use
meet
these
standards
could
enable
people
receive
an
accurate
timely
diagnosis
potentially
benefit
from
new
treatments.
blood
offer
test.
This
Consensus
Statement
provides
recommendations
Protein & Cell,
Journal Year:
2024,
Volume and Issue:
unknown
Published: May 11, 2024
Abstract
Alzheimer’s
disease
(AD),
the
leading
cause
of
dementia,
is
characterized
by
accumulation
amyloid
plaques
and
neurofibrillary
tangles
in
brain.
This
condition
casts
a
significant
shadow
on
global
health
due
to
its
complex
multifactorial
nature.
In
addition
genetic
predispositions,
development
AD
influenced
myriad
risk
factors,
including
aging,
systemic
inflammation,
chronic
conditions,
lifestyle,
environmental
exposures.
Recent
advancements
understanding
pathophysiology
are
paving
way
for
enhanced
diagnostic
techniques,
improved
assessment,
potentially
effective
prevention
strategies.
These
discoveries
crucial
quest
unravel
complexities
AD,
offering
beacon
hope
management
treatment
options
millions
affected
this
debilitating
disease.
JAMA Neurology,
Journal Year:
2024,
Volume and Issue:
81(9), P. 947 - 947
Published: July 28, 2024
Importance
Phase
3
trials
of
successful
antiamyloid
therapies
in
Alzheimer
disease
(AD)
have
demonstrated
improved
clinical
efficacy
people
with
less
severe
disease.
Plasma
biomarkers
will
be
essential
for
efficient
screening
participants
future
primary
prevention
testing
cognitively
unimpaired
(CU)
individuals
initially
low
brain
β-amyloid
(Aβ)
levels
who
are
at
high
risk
accumulating
Aβ.
Objective
To
investigate
if
combining
plasma
could
useful
predicting
subsequent
development
Aβ
pathology
CU
subthreshold
(defined
as
<40
Centiloids)
baseline.
Design,
Setting,
and
Participants
This
was
a
longitudinal
study
including
Swedish
BioFINDER-2
(enrollment
2017-2022)
replication
2
independent
cohorts,
the
Knight
Disease
Research
Center
(Knight
ADRC;
enrollment
1988
2019)
BioFINDER-1
2009-2015).
Included
analysis
convenience
sample
baseline
phosphorylated
tau
217
(p-tau217)
Aβ42/40
assessments
positron
emission
tomography
(Aβ-PET)
or
cerebrospinal
fluid
(CSF)
Aβ42/40.
Data
were
analyzed
between
April
2023
May
2024.
Exposures
Baseline
Aβ42/40,
p-tau217,
ratio
p-tau217
to
nonphosphorylated
(%p-tau217),
p-tau231,
glial
fibrillary
acidic
protein
(GFAP).
Main
Outcomes
Measures
Cross-sectional
PET
CSF
measures
pathology.
Results
included
495
(BioFINDER-2),
283
ADRC),
205
(BioFINDER-1)
participants.
In
BioFINDER-2,
mean
(SD)
age
65.7
(14.4)
261
females
(52.7%).
When
detecting
abnormal
Aβ-status,
combination
%p-tau217
showed
better
performance
(area
under
curve
=
0.949;
95%
CI,
0.929-0.970;
P
<.02)
than
individual
biomarkers.
Aβ-PET,
significantly
associated
Aβ-PET
(n
384)
increases
over
time
224).
Associations
their
interaction
(%p-tau217:
β
2.77;
1.84-3.70;
Aβ42/40:
−1.64;
−2.53
−0.75;
×
−2.14;
−2.79
−1.49;
<
.001)
0.67;
0.48-0.87;
−0.33;
−0.51
−0.15;
−0.31;
−0.44
−0.18;
also
significant
models
predictors.
Similarly,
independently
ADRC
0.71;
0.26-1.16;
.002;
−0.74;
−1.26
−0.22;
.006)
(p-tau217:
−0.0003;
−0.0004
−0.0001;
.01;
0.0004;
0.0002-0.0006;
p-tau231
GFAP
did
not
provide
any
clear
value.
Conclusions
Relevance
this
cohort
suggest
that
p-tau217and
early
stages
accumulation.
These
might
thus
facilitate
trials.
Alzheimer s & Dementia,
Journal Year:
2024,
Volume and Issue:
20(11), P. 8074 - 8096
Published: Oct. 12, 2024
Abstract
INTRODUCTION
Blood
tests
have
the
potential
to
improve
accuracy
of
Alzheimer's
disease
(AD)
clinical
diagnosis,
which
will
enable
greater
access
AD‐specific
treatments.
This
study
compared
leading
commercial
blood
for
amyloid
pathology
and
other
AD‐related
outcomes.
METHODS
Plasma
samples
from
Disease
Neuroimaging
Initiative
were
assayed
with
AD
C2N
Diagnostics,
Fujirebio
ALZPath,
Janssen,
Roche
Quanterix.
Outcomes
measures
positron
emission
tomography
(PET),
tau
PET,
cortical
thickness,
dementia
severity.
Logistic
regression
models
assessed
classification
accuracies
individual
or
combined
plasma
biomarkers
binarized
outcomes,
Spearman
correlations
evaluated
continuous
relationships
between
RESULTS
Measures
p‐tau217,
either
individually
in
combination
biomarkers,
had
strongest
all
DISCUSSION
identified
biomarker
analytes
assays
that
most
accurately
classified
Highlights
p‐tau217
status.
Aβ42/Aβ40
relatively
low
higher
thickness
than
NfL.
Correlations
symptoms
low.
Cell Communication and Signaling,
Journal Year:
2024,
Volume and Issue:
22(1)
Published: Aug. 30, 2024
The
primary
challenge
in
today's
world
of
neuroscience
is
the
search
for
new
therapeutic
possibilities
neurodegenerative
disease.
Central
to
these
disorders
lies
among
other
factors,
aberrant
folding,
aggregation,
and
accumulation
proteins,
resulting
formation
toxic
entities
that
contribute
neuronal
degeneration.
This
review
concentrates
on
key
proteins
such
as
β-amyloid
(Aβ),
tau,
α-synuclein,
elucidating
intricate
molecular
events
underlying
their
misfolding
aggregation.
We
critically
evaluate
mechanisms
governing
elimination
misfolded
shedding
light
potential
strategies.
specifically
examine
pathways
endoplasmic
reticulum
(ER)
unfolded
protein
response
(UPR),
chaperones,
chaperone-mediated
autophagy
(CMA),
intersecting
signaling
Keap1-Nrf2-ARE,
along
with
connected
through
p62.
Above
all,
we
emphasize
significance
quality
control
mechanisms,
encompassing
interventions
targeting
regulation
post-translational
modifications,
enhancement
chaperones
clearance.
Additionally,
focus
current
new,
multi-target
approaches.
In
conclusion,
this
systematically
consolidates
insights
into
emerging
strategies
predicated
aggregates
Chemical Reviews,
Journal Year:
2024,
Volume and Issue:
124(20), P. 11242 - 11347
Published: Oct. 9, 2024
Biopsy,
including
tissue
and
liquid
biopsy,
offers
comprehensive
real-time
physiological
pathological
information
for
disease
detection,
diagnosis,
monitoring.
Fluorescent
probes
are
frequently
selected
to
obtain
adequate
on
processes
in
a
rapid
minimally
invasive
manner
based
their
advantages
biopsy.
However,
conventional
fluorescent
have
been
found
show
aggregation-caused
quenching
(ACQ)
properties,
impeding
greater
progresses
this
area.
Since
the
discovery
of
aggregation-induced
emission
luminogen
(AIEgen)
promoted
advancements
molecular
bionanomaterials
owing
unique
high
quantum
yield
(QY)
signal-to-noise
ratio
(SNR),
Alzheimer s & Dementia Diagnosis Assessment & Disease Monitoring,
Journal Year:
2025,
Volume and Issue:
17(1)
Published: Jan. 1, 2025
Abstract
INTRODUCTION
Blood‐based
biomarkers
seem
promising
for
the
diagnosis
of
Alzheimer's
disease
(AD).
METHODS
We
performed
a
systematic
review
and
meta‐analysis
on
potential
blood
phosphorylated
Tau181
(p‐tau181)
to
differentiate
amyloid‐positive
(A+)
amyloid‐negative
(A−)
subjects.
Two
meta‐analyses
were
conducted,
showing
mean
p‐tau
values
in
cerebrospinal
fluid
(CSF)
A+
A−
group,
second
comparing
concentrations
CSF
among
versus
A‐
participants,
by
laboratory
assessment
method.
RESULTS
Eighteen
studies
(2764
5646
subjects)
included.
The
single‐group
showed
higher
p‐tau181
than
group.
In
head‐to‐head
meta‐analysis,
reliably
differentiated
patients
from
participants.
DISCUSSION
Regardless
technique,
differentiates
Therefore,
it
might
have
important
applications
early
inclusion
clinical
trials
AD
patients.
Highlights
role
blood‐based
discriminating
is
still
uncertain.
Blood
distinguishes
allow
trials.
