The
capability
of
antibodies
to
neutralize
different
SARS-CoV-2
variants
varies
among
individuals
depending
on
the
previous
exposure
wild-type-
or
Omicron-specific
immunogens
by
mono-
bivalent
vaccinations
infections.
Such
profiles
neutralizing
(nAbs)
usually
have
be
assessed
laborious
live
virus-neutralization
tests
(NTs).
We
therefore
analyzed
whether
a
novel
multivariant
surrogate
virus
neutralization
test
(sVNT)
(adapted
from
commercial
microarray)
that
quantifies
antibody-mediated
inhibition
between
receptor
angiotensin-converting-enzyme
2
(ACE2)
and
variant-specific
receptor-binding
domains
(RBDs)
can
assess
activity
against
wild-type,
Delta
Omicron
BA.1,
BA.2
BA.5
(sub-)
after
booster
with
Omicron-adapted
vaccines
in
manner
similar
live-virus
NTs.
Indeed,
using
NTs
as
reference,
we
found
significant
correlation
NT
titers
levels
ACE2-RBD
binding
(p
<
0.0001,
r
≤
0.78
respectively).
Furthermore,
sVNTs
identified
higher
values
BA.1
vaccinated
than
those
monovalent
wild-type
vaccines.
Our
data
thus
demonstrate
ability
detect
nAbs
following
PeerJ,
Journal Year:
2024,
Volume and Issue:
12, P. e18384 - e18384
Published: Nov. 11, 2024
Background
Limited
data
on
SARS-CoV-2
seroprevalence
in
rural
areas
of
northern
Germany
necessitate
comprehensive
cohort
studies.
We
aimed
to
evaluate
the
seroprevalence,
silent
infection
(SI)
rates
and
risk
factors
for
infections
among
children
adolescents
Western
Pomerania
from
December
2020
August
2022.
Methods
In
this
cross-sectional
study,
serum
or
plasma
samples
(6
months
17
years)
were
collected
during
routine
blood
draw.
specific
antibodies
(S1
nucleocapsid)
their
neutralizing
capacity
analyzed
using
commercially
available
enzyme-linked
immunosorbent
neutralization
assays.
Socio-demographic
information
about
vaccination
obtained.
Multivariable
logistic
regression
was
used
identify
independent
SI.
Results
A
total
1,131
included
into
study.
Overall,
25.1%,
strongly
influenced
by
pandemic
course,
predominant
virus
variants,
age
approval
vaccination.
SI
rate
5.4%
(95%-CI
[3.7%–6.8%])
unvaccinated
undiagnosed
over
entire
study
period
with
highest
adolescents.
Main
factor
despite
time
at
an
infected
household
member
(Odds
ratio
=
9.88,
95%-CI
[4.23–22.9],
p
<
0.001).
Factors
associated
overall
(known
silent)
also
include
a
17.8,
[10.7–29.6],
Conclusions
believe
that
introduction
governmental
measures
systematic
test
strategies
schools
impacted
rate,
as
we
suspect
asymptomatic
cases
have
already
been
identified,
resulting
surprisingly
low
identified
our
IJID Regions,
Journal Year:
2023,
Volume and Issue:
7, P. 277 - 280
Published: May 12, 2023
Commercial
severe
acute
respiratory
syndrome
coronavirus
2
(SARS-CoV-2)
antibody
tests
were
developed
before
variants
with
spike
protein
mutations
emerged,
leading
to
concerns
that
these
have
reduced
sensitivity
for
detecting
responses
in
individuals
infected
Omicron
subvariants.
This
study
was
performed
evaluate
Abbott
ARCHITECT
serologic
assays,
AdviseDx
SARS-CoV-2
IgG
II,
and
the
detection
of
(S)
nucleocapsid
(N)
increases
vaccinated
healthcare
workers
During
BA.1/2
BA.4/5
waves,
171
SARS-CoV-2-infected
(122
wave,
49
wave)
tested
S
N
post
infection.
Sequencing
variant
confirmation
on
nasal
swab
samples
from
during
wave.
Twenty-seven
sequence
confirmed
wave
all
had
pre-infection
data.
Compared
levels,
post-infection
increased
6.6-fold
1294
±
302
BAU/ml
(mean
standard
error
measurement)
9796
1252
(P
<
0.001)
3.6-fold
1771
351
8224
943
infection
19.1-fold
0.2
0.1
3.7
0.5
13.5-fold
0.22
3.2
0.3
Among
159
infection-naïve
individuals,
positive
levels
detected
a
88%
87
who
between
14
days
60
The
large
along
comparable
previously
reported
data
unvaccinated
after
infection,
support
use
assays
seroconversion
Given
68%
United
States
population
is
fully
vaccinated,
results
are
current
relevance.
medRxiv (Cold Spring Harbor Laboratory),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Oct. 10, 2023
ABSTRACT
Virus-specific
antibodies
are
important
determinants
of
protective
immunity
against
severe
acute
respiratory
syndrome
coronavirus
2
(SARS-CoV-2).
While
regarded
as
the
gold
standard
for
detecting
functional
antibodies,
conventional
virus
neutralisation
tests
(VNT)
or
pseudotyped
(pVNT)
require
biosafety
level
3
facilities.
Alternatively,
virus-free
surrogate
test
(sVNT)
quantifies
inhibitory
that
prevent
spike
protein
from
binding
to
its
receptor,
human
angiotensin-converting
enzyme
(hACE2).
We
evaluated
secreted
nanoluciferase
(NLuc)-tagged
(S)
fragments
diagnostic
antigens
in
sVNT
framework
a
vaccination
study.
First,
different
lengths
were
tested
their
suitability
capture
immunoassay
(EIA)
using
unprocessed
culture
supernatants
transfected
cells,
identifying
receptor
domain
(RBD)
S
optimal
construct.
The
sensitivity
in-house
relying
on
NLuc-labelled
RBD
equalled
surpassed
commercial
(
cPass
,
GenScript
Diagnostics)
and
an
pVNT
four
weeks
after
first
(98%
vs.
94%
72%,
respectively),
reaching
100%
all
assays
second
third
vaccinations.
Additionally,
serum
reactivity
with
constructs
Omicron
BA.1
was
tested.
Compared
EIA,
displayed
superior
discrimination
between
wild-type-
variant-specific
sera.
Differences
most
pronounced
vaccinations,
whereas
resulted
robust,
cross-reactive
detection
constructs.
In
conclusion,
utilising
permit
quantification
assessment
SARS-CoV-2-specific
differences
reactivity.
Potential
applications
include
monitoring
therapy
vaccine
efficacy
follow-up
prolonged
disease
courses
high-risk
groups.
Designed
straightforward,
highly
flexible
modular
systems,
these
can
be
readily
adapted
further
emerging
viral
variants.
Microbiology Spectrum,
Journal Year:
2023,
Volume and Issue:
11(6)
Published: Nov. 1, 2023
ABSTRACT
Immunity
following
infection
and
vaccination
with
the
SARS-CoV-2
Omicron
variant
is
poorly
understood.
The
aim
was
to
investigate
immunity
assessed
antibody
response,
neutralizing
antibodies
(NAbs),
IFN-γ
release
under
different
scenarios:
in
vaccinated
unvaccinated
individuals
without
variant.
This
nationwide
single-center
study
conducted
between
January
March
2022,
where
all
convalescent
were
infected
included
six
groups:
unvaccinated-naïve,
convalescent,
vaccinated-naïve
(second
dose),
(third
dose).
Antibody
responses
by
determining
receptor
binding
domain-specific
NAbs
levels
serum,
IgG
saliva.
T-cell
whole
blood
measured
as
released
after
stimulation
spike
peptides.
We
found
that
humoral
response
against
protein
higher
among
than
convalescent.
Unvaccinated
had
comparable
low
responses,
while
those
a
second
or
third
dose,
independent
of
status,
increasingly
levels.
Only
22%
mounted
consistent
detectable
infection.
However,
98%
peptide
release.
In
conclusion,
primary
mounts
immune
significantly
enhanced
prior
vaccination.
induced
robust
both
vaccinated,
demonstrating
evasive
potential
affects
more
immunity.
IMPORTANCE
investigated
scenarios
whereas
minor
fraction
infection,
almost
positive
responses.
evasion
The
capability
of
antibodies
to
neutralize
different
SARS-CoV-2
variants
varies
among
individuals
depending
on
the
previous
exposure
wild-type-
or
Omicron-specific
immunogens
by
mono-
bivalent
vaccinations
infections.
Such
profiles
neutralizing
(nAbs)
usually
have
be
assessed
laborious
live
virus-neutralization
tests
(NTs).
We
therefore
analyzed
whether
a
novel
multivariant
surrogate
virus
neutralization
test
(sVNT)
(adapted
from
commercial
microarray)
that
quantifies
antibody-mediated
inhibition
between
receptor
angiotensin-converting-enzyme
2
(ACE2)
and
variant-specific
receptor-binding
domains
(RBDs)
can
assess
activity
against
wild-type,
Delta
Omicron
BA.1,
BA.2
BA.5
(sub-)
after
booster
with
Omicron-adapted
vaccines
in
manner
similar
live-virus
NTs.
Indeed,
using
NTs
as
reference,
we
found
significant
correlation
NT
titers
levels
ACE2-RBD
binding
(p
<
0.0001,
r
≤
0.78
respectively).
Furthermore,
sVNTs
identified
higher
values
BA.1
vaccinated
than
those
monovalent
wild-type
vaccines.
Our
data
thus
demonstrate
ability
detect
nAbs
following
