Characterization of immunopathological changes in the feather pulp of CVI988-vaccinated pullets challenged with a very virulent plus Marek’s disease virus strain
Avian Pathology,
Journal Year:
2025,
Volume and Issue:
unknown, P. 1 - 39
Published: Feb. 28, 2025
AbstractHigh
load
of
oncogenic
Marek's
disease
virus
(MDV)
DNA
in
the
feather
pulp
(FP)
as
early
21
days
age
is
a
powerful
criterion
to
predict
outcome
(MD)
apparently
healthy
chickens.
The
objective
this
study
was
elucidate
immunopathological
changes
FP
21-days-old
chickens
that
had
been
vaccinated
with
CVI988
vaccine
(healthy),
and
challenged
very
virulent
plus
(vv+)
MDV
strain
648A
(well
protected),
or
were
unvaccinated
(not
protected)
when
compared
non-infected
naïve
Oncogenic
load,
histopathological
immunohistochemical
evaluation
lesions,
immunophenotypic
characterization
infiltrates
by
flow
cytometry
conducted.
Our
results
demonstrate
infected
non-vaccinated
significant
increase
percentage
CD3+
T
cells,
mainly
CD4
+
MHC-II
cells
CD8
all
other
groups.
They
also
significantly
decreased
number
CD8β+
Infection
reduced
macrophages
not
only
group
but
CVI988/648A
group.
In
addition,
groups
CVI988,
regardless
challenge
status,
higher
levels
suggesting
has
an
enhancing
effect
on
CTL
cells.
showed
highly
correlated
infiltration
provide
further
confirmation
indeed
appropriate
sample
for
diagnosis
MD.
Language: Английский
Protection Conferred by Gallid Alphaherpesvirus 2 Vaccines Against Immunosuppression Induced by Very Virulent Plus (vv+) Marek’s Disease Virus Strains in Commercial Meat Type Chickens
Pathogens,
Journal Year:
2025,
Volume and Issue:
14(1), P. 54 - 54
Published: Jan. 10, 2025
Very
virulent
plus
Marek’s
disease
virus
(vv+MDV)
induces
severe
immunosuppression
in
commercial
chickens.
In
this
study,
we
evaluated
how
three
Gallid
alphaherpesvirus
2
(GaHV-2)
vaccines
(CVI-988,
rMd5-BAC∆Meq,
and
CVI-LTR)
protected
against
two
negative
outcomes
of
vv+MDV
infection:
(1)
reduced
viability
frequency
immune
cells
the
spleen
(2)
decreased
efficacy
CEO
(chicken
embryo
origin)
vaccine
infectious
laryngotracheitis
challenge.
At
25
days
post-infection
with
686,
all
are
splenocytes.
However,
there
were
differences
splenic
immunophenotypes
among
groups.
Compared
to
uninfected
control,
B
was
CVI-988/686
group
but
not
rMd5-BAC∆Meq/686
CVI-LTR/686
T
cell
subset
frequencies
showed
no
difference
between
controls
CVI-988/686;
however,
a
reduction
activated
CD4+
CD4+,
CD8+,
γδ+
group.
We
also
demonstrated
that
MDV-induced
tumors,
only
rMd5-BAC∆Meq
CVI-LTR
impact
648A
strain
on
efficacy.
Our
findings
demonstrate
important
biology
and/or
mechanisms
protection
these
vaccines.
Language: Английский