Lecture 12 - Ac#ve
and
Passive
Immunity
 Ac$ve
immunity
 –  immunity
from
experience
 – 

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 3/16/10 Ac#ve
and
Passive
Immunity
 Ac$ve
immunity
 –  immunity
from
experience
 –  the
immune
system
is
exposed
to
the
an$gen
in
the
 natural
course
of
life
and
immune
cells
respond
and
 ac$vely
combat
the
pathogen
 Passive
immunity

 –  occurs
when
an$bodies
are
transferred
without
 s$mula$ng
the
immune
system
 –  i.e.,
from
mother
to
infant
(through
breastmilk)
 Trainable
 The
primary
advantage
of
ac$ve
immunity
comes
from
the
crea$on
of
 memory
cells
 Memory
cells
produced
during
the
primary
response
remain
in
the
body
 for
years
 The
secondary
response
to
a
par$cular
an$gen
happens
far
faster
than
 the
first
response
because
the
immune
system
needs
to
s$mulate
 and
clone
only
the
memory
cells
 Secondary
responses
also
require
less
energy
from
the
body
 Ac#ve
Immunity
 Ac#ve
Immunity
 Autoimmune
Diseases
 An
autoimmune
response
is
an
immune
response
in
which
the
body
aEacks
itself
 Autoimmune
diseases
have
different
effects
depending
on
what
$ssue
is
under
aEack
 –  Mul$ple
sclerosis
–
aEack
is
directed
against
nervous
$ssue
 –  Crohn's
disease
–
aEack
is
directed
against
the
absorp$ve
por$on
of
the
gut
 –  Type
I
diabetes
mellitus
–
a:acks
the
pancreas
 –  Lupus
‐
the
site
of
the
aEack
may
vary
(it
may
affect
the
skin,
joints,
kidney,
 and/or
lungs)

 –  Rheumatoid
arthri$s
–
aEacks
the
joint
capsules
of
the
body
 Chapter
10.3
 Infec#ous
Disease
and
 Epidemiology:
 Viruses
 1 3/16/10 Viruses
 Viruses
lack
most
characteris$cs
of
life
 – they
cannot
reproduce
without
a
host
cell
 – they
do
not
metabolize
 – they
are
not
composed
of
cells

 A
virus
is
“merely
a
snippet”
of
nucleic
acid
(either
 DNA
or
RNA,
but
not
both)
contained
inside
a
 protein
coat,
called
a
capsid
 Viruses
 Viruses
are
very
small
 Viruses
mutate
easily
and
frequently
 No
“cure”
for
viral
disease
 Treatment=
immune
system
 Viral
Disease
 Viral
diseases
include

 –  Ebola
 –  AIDS
 –  Chickenpox
 –  Influenza 
 
 –  Herpes
 –  Polio
 –  Rabies
 –  Hantavirus
 –  HPV
 Viruses
 

 Viruses
 Some
viruses,
called
bacteriophages,
aEack
 bacteria
(oZen
used
in
recombinant
 engineering)
 Viruses
are
cellular
parasites
 – Contact
preferred
host
cell,
they
inject
their
 nucleic
acid
into
the
host
and
take
over
its
 func$oning

 – host
cell
becomes
a
viral
factory,
producing
 new
viruses
at
an
alarming
rate
 Viruses
 Viruses
are
not
affected
by
an#bio#cs
 – they
have
no
cell
wall
to
break
down
 – no
metabolic
pathways
to
destroy
 – no
protein
synthesis
to
disrupt
 2 3/16/10 Viruses
 Viral
DNA
can
have
to
phases:
 – Lysogenic
cycle
of
replica$on:
remain
 dormant
in
the
host
cell
 – Ly$c
cycle:
immediately
affect
the
cell
 Viruses
 Most
epidemics
caused
by
virus
 No
an$bio$cs
 A
few
drugs
can
address
 replica$on
inhibi$on
of
some
 viruses:
 –  HIV
 –  Herpes
 Treat
symptoms,
wait
for
 immune
system
 –  Vaccines
 3 ...
View Full Document

This note was uploaded on 10/27/2010 for the course BIOL 125 taught by Professor Klein during the Spring '10 term at CUNY Hunter.

Ask a homework question - tutors are online