immunobiology cont... Flashcards
8
what percent protein should serum be in a healthy animal?
What is it made up of?
6-7%
-half of this protein is albumin and the other globulin (further divided into alpha, beta, gamma
what part of proteins are antibodies found?
gamma globulin protein
normally circulate in the blood but are occasionally found in the tissues
inadequate response
for some reason the immune system is not producing adequate levels of antibody
can happen due to certain drugs, infections
immunodeficient
inadequate immune response
hypersensitivity
exaggerated immune response
eg. allergies
good antigens
antigens that can readily stimulate an antibody response in a host
what can antigens be made of
many things
whole bacterial cells, egg albumen, or anything that is a foreign protein
are all antigens harmful?
no
H-antigens
flagellar antigens
made from the flagella of a bacteria
O antigens
made from the cell bodies of bacteria
vaccine antigens must be _____ , _____ and _____
pure
have the required potency/concentration
safe
what are the 2 stages of adaptive immune response?
primary immune response
secondary immune response
these stages are manipulated by modern vaccine therapy
primary immune response
occurs the very first time the adaptive response engages a particular substance (only then)
antigen enters the body
- is detected by B lymphocytes in the lymph nodes
- B lymphocytes produce antibodies to the antigen
- response is slow (several days) (latency period) (gradual increase)
- IgM antibody is produced (does not last long in the body)
- response is weak (low titer)
- gradually decreases if they never encounter it again
bell curve
what do B lymphocytes produce
humoral antibodies
secondary immune response
occurs every time but the first time an antigen is encountered
- B lymphocyte is re-exposed to an antigen and incites the secondary immune response
- the B lymphocytes remember the antigen and produce copious amounts of antibodies (secondary response)
- rapid (1-2 days) (short latency period)
- IgG antibody is produced and persists in the system for months to years
- strong response
- high titer
protects from the disease possibly more than once
the virus in the vaccine is too _______ to cause disease but _________ ___________ to stimulate a primary immune response
weak
strong enough
anamnestic response
- accelerated response of antibody production
- is seen when an antigen that the body has seen before is injected into the animal
- this is because the B lymphocytes remember the antigen and produce more antibodies than the first time
hyperimmunization
maximum antibody response to an antigen
is achieved by repeated injections of antigen over a period of time
immunoglobulins (Ig)
the group of antibodies produced because of antigen stimulation
electrophoresis
separates the various immunoglobulin components
- put the immunoglobulin into an electric field and the proteins will move (at different rates) and will separate by weight
glycoproteins
antibodies
( non-cellular)
what do antigens bind to?
antigenic determinant / epitopes
what are the 5 sub-classes of immunoglobulins?
IgM
IgG
IgA
IgD
IgE
IgM
- largest
- first to appear in an antibody response
- produced by B lymphocytes
-vis secreted during the primary response by B cells - enhances phagocytosis by WCBs
- stays in the vascular system
- 10% of our antibodies
IgG
- produced after IgM
- most plasma cells produce IgG during secondary immune responses
- neutralizes toxins and viral agents
- can cross the placental barrier in primates, rodents, cats and dogs
- Short-term immunity
IgA
- protect mm
- main one in colostrum
- plasma cells in lymph nodes that drain partial entries (eg, GI tract, UG tracts), will produce IgA
- found in body secretions (tears)
- binds to the invader, this blocks its ability to bind to the host tissue but also makes it too large to pass through the mucosal membrane
IgD
- used for cancer diagnosis in humans
- activates lymphocytes
- found on lymphocyte membranes
- primary role is as an antigen receptor for B cells
IgE
- responsible for allergic response
- boosts local inflammatory levels
- protects from helminths by attracting eosinophils
- response can become damaging in excess. If the reaction is localized it is an allergy, when it is systemic, it is a hypersensitivity called anaphylaxis
Immunopathological disorders
hypersensitivities, autoimmune reactions, immunodeficiencies
result from inappropriate or inadequate immune responses
Immunoproliferative disorders
proliferation of the leukocytes become aberrant, excessive, and/or non-functional
- characterized by the rapid production of lymphoid cells producing immunoglobulins
- eg lymphosarcoma
Immunodeficiency
the lack of all or part of the immune system’s functions (may be fatal)
eg.
1. congenital cell-mediated immunodeficiency (decrease in a WBC)
2. congenital humoral immunodeficiency (inability to produce certain classes of antibody)
3. combined immunodeficiency (anim does not possess a thymus, or lymphoid organs, and has a low WBC count
immunological tolerance
the antibody-forming mechanism within the body that knows how to recognize its own tissue
on the 42nd day of gestation, the RES is instructed to label all cells present as self (we can lose this ability)
how can tolerance be induced?
drugs
eg steroids
autoantibodies
when immunological tolerance decreases and antibodies start breaking down the host cells
Formation of lymphocytes
- starts in the bone marrow (stem cell)
- splits into (1. thymus, where they become T lymphocytes, are influenced by thymic hormones) OR (2. GALT tissue, where they form B lymphocytes, are influenced by GALT hormones)
- the T and B lymphocytes end up in either the spleen or the lymph nodes
Humoral immunity
due to the presence of IgG and IgM antibodies in the bloodstream
after being exposed previously to the antibody the animal will respond by activating B lymphocytes to produce specific antibodies
what are the 2 groups of the adaptive immune system?
- antibody production ( humoral immunity)
- cell-mediated immunity
cell-mediated immunity
when CELLS play the predominant role in immune function
helper t cell
present in both innate and adaptive immunity
how do macrophages aid in immunity
- phagocytize antigens
- presents a piece of the antigen (epitope) on its surface for the B cells
lymphokines
cytokines produced by the helper t cells,
further activates the macrophage
attracts macrophages
what are the different lymphokines
interleukin 1,2,4,6
interleukin 1
produced by macrophage
causes helper t cells to release more interleukin
interleukin 2
causes more T cells to be produced
interleukin 4 and 6
cause b lymphocytes to clone and produce memory cells and antibodies
what cells are responsible for the harmful effects of hypersensitivity and tissue graft rejection
T lymphocytes
Total lymphocyte count
T (40-70%) + B (20-40%)
- gives a rough indication of the immune status of an animal
mucosal immunity
- protects from infection on inner surfaces
- not dependent on humoral antibodies or cell-mediated immunity
- uses locally produced IgA antibodies
- critical for respiratory tract infections
what is the most important antibody producing organ?
spleen
toxin
- substances capable of causing disease in susceptible animals
- protein chemical structure
- destroyed by heat
- are often more potent antigens (the body can form many antibodies)
toxoid
a toxin treated to destroy its toxicity without destroying antigenicity.
antitoxin
is a concentrated mixture of antibodies derived from animals that have been injected with the toxoid
type of passive immunity
what are the 4 basic types of immunity
native defense mechanisms
humoral immunity
cell-mediated immunity
mucosal immunity
