Zusammenfassung der Ressource
Monoclonal Antibodies
and Vaccines
- Immunoglobulins
(antibodies)
- Y-shaped
proteins
- Locate and
neutralise foreign
particles in the body
- Each specific to
a unique part of
a foreign object
- Antigens
- Conserved
and variable
regions
- Each tip
contains a
paratope
- Specific for
a particular
epitope on
an antigen
- Key
- Allows precise
binding of antigens
and antibodies,
which tags foreign
particles for attack by
the immune system
- Lock
- Formed from two
heavy polypeptide
chains and two
light polypeptide
chains, with two
variable sites for
antigen recognition
- Polyclonal
antibodies
- Derived from
many B cell lines
and were first used
to treat infectious
diseases
- Tetanus and
diphtheria
- Use limited due to
low reproducibility
and consistency
and variable toxicity
- Monoclonal
Antibodies
- Derived from
identical B cells
that are clones
of a parent cell
- Monospecific
for a certain
antigen
- Can be produced in
bulk to identify, bind to
or eliminate a target
substance in the blood
- Used massively
in biochemistry
and medicine
- Currently 21
human therapeutic
monoclonal
antibodies, with
over 100 more in
clinical trials
- Produced by
injecting a mouse
with an antigen,
causing its immune
cells to produce the
complementary
antibody, immunising
the animal
- Immune cells that
produce the antibody
are isolated,
extracted and fused
with tumour cells,
making hybridomas
- Unfused cells die as
they lack the HGPRT
enzyme to survive in
a HAT medium
- Hybridomas are
screened for antibody
production and then are
cloned, making many
cells which all produce
the desired antibody
- Used in the treatment of
cancer, autoimmune
diseases, eye disorders
and cardiovascular systems
- Chimeric
Antibodies
- Fusion
Antibodies
- Produced from the
recombination of
genes coding for
antibodies
- An all-rodent antibody
the would not function
in a human can be
fused with an
all-human antibody
- Creates a chimeric
humanised antibody
- Originally produced in
the mouse but is fully
functional in humans,
with around 90%
human sequence
- Less
immunogenic
- Less able to
produce an
immune response
- Examples
- Rituxan
- Used for treating
Non-Hodgkins
lymphoma
- Remicale
- Used for treating
rheumatoid arthritis
and Crohn's disease
- Human
antibody
libraries
- Created by
obtaining
immune serum
from patients
- Or by
mutagenesis
with PCR
techniques that
are more prone
to mutations
- Increases the
variability of
the antigens
- Vaccines
- Biological
preparations that
boost the immune
system to protect
agains pathogens
- Types
- Live
attenuated
- Pathogen grown in
culture, usually as
a less virulent form
- Killed/inactive
- Pathogen is
chemically
inactivated
- Inactivated by
things such as
formaldehyde
- Subunit
- Use antigenic parts
of the pathogen,
which can still illicit
a response
- Under
development
- Recombinant
adenoviral
vectors
- Efficient
delivery system
into human cells
- Viruses genetically
altered to carry
foreign proteins,
which elicit an
immune response
- By combining the
physiology of one pathogen
and the DNA of another,
vaccinations can be carried
out for diseases with
complex infection methods
- Recombinant
BCG vaccines
- Made up of genes
of various strains of
pathogen
- Very efficient
B and T cell
responses
- DNA
vaccines
- Plasmid DNA
(antigenic transgenes)
are injected with an
immunomodulator to
increase their
transcription and
efficacy
- Adjuvant
- Added to a vaccine
to boost the resulting
immune response to
the antigen
- Act in
various
ways
- As an antigen store
- releases slowly to
maximise response
- As an irritant -
causes the body
to recruit and
amplify response
- Activates T
cells and
lymphocytes
- Many different
types, from
inorganic
compounds
such as
aluminium
hydroxide to
emulsifying oils
- Some side
effects
include
inflammation
- Toll-like
receptors
- Key role in
the immune
response
- Detect foreign
particles and
elicit a response
- Receptors in
dendritic cells
- Provide early detection
of things such as
ssRNA (viral particles)
and LPS (bacterial
membrane proteins)
- Understanding of this
mechanism allows
specific targeting of parts
of the immune response
and allows for a more
versatile vaccine design
- Adjuvants could
be added to the
vaccine to activate
certain TLRs
- Viruses mutate and evolve,
so vaccinations often need
to protect from multiple
strains of the same infection
- The Avian Influenza
virus crossed the
species barrier in 1918,
infecting humans
- H1N1
- Main antigens
are referred to
in the name
- Haemaglutinin
(HA)
- Neuraminidase
(NA)
- This virus has
mutated many times
since, changing the
gene sequence which
codes for the antigens
- Given rise to
new strains
- H2N2
- H3N2
- Vaccination must
therefore protect
against all of these
strains, as all of
them still exist