-
the physiological activity that alerts the body to the entrance of foreign material and destroys or renders them harmless
immunity
-
foreign substances to the body
antigen
-
6 examples of antigens
- bacteria
- viruses
- fungi
- various unicellular and multicellular organisms (ameba, parasitic worms)
- foreign tissues (cancers or organs)
- materials (pollen)
-
type of WBC that is associated with resistance to specific diseases
lymphocyte
-
nonviable substance that is associated with resistance to specific diseases
antibody
-
external obstacles to protect the body from antigens
protective barriers
-
5 protective barriers
- skin
- tears
- sweat
- mucus
- gastric fluids
-
2 antimicrobial substances produced by the immune system
-
What is interferon?
- Antimicrobial
- It is a type of protein produced by virus infected host cells which causes uninfected host cells to synthesize a type of protein that inhibits the intracellular replication of viruses.
-
What is complement?
- Antimicrobial
- group of proteins in serum that contribute to resistance and immunity by:
- activation of inflammation
- opsonization
- cytolysis
-
initiating an inflammatory reaction which causes blood cells to gather at the site of antigenic attack
activation of inflammation
(one of the mechanisms of compliment)
-
coating foreign substances with an adherent material, which causes antigens to be more easily destroyed by other cells
opsonization
(a mechanism of compliment)
-
the activation of a membrane attack complex (MAC) that punches holes in a microbe causing it to rupture
cytolysis
(a mechanism of compliment)
-
the ingestion and destruction of microbes or foreign matter by cells called phagocytes
phagocytosis
-
-
phagocytes which are granulocytes--neutrophils in particular
microphages
-
phagocytes which are monocytes which have enlarged and become more numerous because of infection
macrophages
-
4 mechanisms involved with phagocytosis
- chemotaxis
- adherence
- ingestion
- digestion
-
attraction of the phagocytes to the site of infection
chemotaxis
-
attachment of a microbe to the surface of the phagocyte (usually after compliment coats the microbe through opsonization)
adherence
-
before adherence (in phagocytosis) takes place, what substance usually coats a microbe first to facilitate attachment ?
compliment
-
pseudopods extend from the surface of the phagocyte and enclose the mircrobe in a phagocytic vesicle which is drawn into the phagocyte
ingestion
-
"false feet" that extend from the surface of the phagocyte and enclose the microbe
pseudopods
-
During ingestion what is the ingested microbe inclosed within?
phagocytic vesicle
-
lysosomes and digestive enzymes kill and break down the microbe
digestion
-
lysosomes
garbage can of cells
-
What happens to ingested materials after they have been digested by phagocytes?
some of the microbe materials are used by the phagocyte, the rest is expelled from the surface as a residual body
-
expelled product of a phagocyte
residual body
-
substance that, when introduced into the body, causes the body to produce antibodies which react with it
antigen
-
structures found on the surface of antigens
antigenic determinant sites
-
another name for antigenic determinant site
epitopes
-
specific locations on surfaces of antigens that trigger specific antibodies
antigenic determinant sites (epitopes)
-
what effect do antigenic determinant sites have upon antibodies
they trigger specific antibodies
-
How many epitopes are recognized by the human immune system?
at least a billion
-
what is immunogenicity?
ability to stimulate the formation of specific antibodies
-
What is reactivity?
the ability of antibodies to react with specific antigens
-
epitopes are characterized by....
immunogenicity and reactivity
-
protein substances produced by the body to neutralize a specific antigen
antibody
-
what type of organic molecule is an antibody?
glycoprotein
-
What type of glycoproteins are antibodies?
globulins
-
What are antibody globulins called?
immunoglobulins (Igs)
-
structure of an immunoglobulin
4 polypeptide chains joined together by disulphate bond
- 2 long heavy (H) chains
- 2 short light (L) chains
-
what holds the 4 polypeptide chains together
disulphate bonds
-
Are the tips of the H and L chains the same for all antibodies?
no, they are different for each kind of antibody
-
the tips of the 4 polypeptide chains that make up an antibody are called....
variable (V) regions
-
What do the V regions of the antibody chains contain?
binding sites
-
region of the antibody peptide chains that is the same in all antibodies for each of the 5 classes of immunoglobulins
constant (C) region
-
2 regions of the antibody polypeptide chains
- variable (V) region
- constant (C) region
-
how many classes of immunoglobulins are there? Name them.
-
IgG
- enhances phagocytosis
- neutralizes toxins
- protects newborn infants (crosses the placenta)
-
IgA
- protects mucosal surfaces
- found in tears, saliva, and milk
- decreases during times of stress (which lowers threshold for infection)
-
IgM
- causes agglutination and lysis
- found mainly in blood and lymph
-
IgD
stimulates antibody production (tells them to form)
-
IgE
involved in allergic reactions
-
How is the amount of antibody present in serum measured?
by it's titer
-
When are titers highest?
when the immune system is stimulated by it's corresponding antigen
-
How many types of lymphocytes are there? What are they?
-
lymphocytes originate from...
hemocytoblasts (stem cells) in the bone marrow
-
function of T-cells
aggressively attack the invading antigens by physical contact and the secretion of toxins and enzymes
-
Why are T cells called T cells?
T is for thymus where the T cells are activated
-
what is meant by T cells become activated?
undergo an "aggressive" change
-
Describe how T-cells become immunologically aggressive.
they come in contact with an antigen
-
When a T cell responds to an antigen it is said to be __________.
sensitized
-
Where do sensitized T cells tend to congregate?
at the site of infection
-
What does a sensitized T cell do in response to an infection?
congregates at the site of the infection, then divides to form different types of T cells
-
Names of 6 subpopulation T cells that sensitized T cells develop into
- amplifier T cells
- memory T cells
- helper T cells
- suppressor T cells
- killer T cells
- delayed hypersensitivity T cells
-
primary function of amplifier T cells
increase activity of other T cells
-
memory T cells
provide rapid protection against later infections (remember which chemical worked best, not antibody)
-
another term for helper T cell
CD4 cells
CD stands for cluster designation and refers to specific protein markers found in WBCs
-
primary function of helper T cells
- signal B cells to produce antibodies
- secretes interleukin 2 (which initiates the production of killer T cells)
-
initiates the production of killer T cells
- interleukin 2
- (produced by helper T cells)
-
function of suppressor T cells
suppress the activities of all T cells after the danger has passed
-
Another term for killer T cells
CD8 cells
-
primary function of killer T cells
cause direct destruction of the antigens by secretion of chemical substances that result in agglutination and lysis and interfere with virus replication
-
primary function of delayed hypersensitivity T cells
important in allergy responses
-
primary function of B cells
produce antibodies
-
where do B cells originate?
within bone (B) marrow
-
why are B cells called B cells
originated in bone marrow (B is for bone)
-
what is meant by B cell activation
develop into specialized aggressive cells
-
Where are B cells primarily found?
lymphatic tissue (not in the blood like T cells)
-
In what type of tissue to B cells become sensitized to an antigen?
lymphatic tissue
-
Subpopulations that B cells differentiate into
- Helper T cells
- plasma cells
-
When activated by an antigen, the B cells remain in the lymphatic tissue where some differentiate into______________ cells.
plasma cells
-
What cells produce antibodies?
plasma cells formed from B cells
-
What do plasma cells do?
produce antibodies
-
What provides the stimulus for plasma cells to produce antibodies?
Helper T cells
-
Functions and actions of memory B cells
respond rapidly with antibodies if exposed to the same antigen in the future
(store blue print for antibody)
-
2 types of immunity
- cellular (cell mediated) immunity - T cells
- humoral (antibody mediated) immunity - B cells
-
another name for cellular immunity
cell mediated immunity
-
type of immunity where the lymphocyte comes in contact with the surface of the antigen and secretes destructive toxins and enzymes causing agglutination and lysis
cellular immunity
-
In cellular immunity, the substances available to the lymphocyte to aid in the destruction or neutralization of the antigen
toxins and enzymes
-
type of lymphocyte involved in cellular immunity
T cells
-
cellular immunity is especially effective against....
fungi, parasites, cancer cells, and foreign tissue
-
another term for humoral immunity
antibody mediated immunity
-
where circulating antibodies neutralize the invading agent
humoral immunity
-
type of lymphocyte involved in humoral immunity
B cells
-
Humoral immunity is especially effective against....
viral and bacterial infections
-
the ability to recognize and respond to specific antigens if such antigens are reintroduced into the body at some future date
immunological memory
-
How long may immunological memory remain?
decades or a lifetime
-
How many responses are there to immunological memory? What are they?
2
- primary response
- secondary response
-
What cells are primarily involved in immunological memory?
- memory B cells
- memory T cells
-
When an antigen is first encountered by the immune system, there is no antibody present and the individual ma become_________ ___________.
very sick
-
After the first few days of primary immune response there is a slow rise in antibody ________ and the individual becomes clinically improved due to the increasing presence of _____________.
-
In primary immune response, after the antigenic threat has been removed the antibody titer _______ ___________.
gradually declines
-
What would precipitate the secondary response?
if the same antigen is encountered again
-
Why doesn't a person become sick in a secondary response?
it's so quick and effective the antigens are neutralized before any signs or symptoms of disease become evident
-
What happens in secondary response?
If same antigen is encountered again, there is a faster and greater rise in antibody titer, especially with Ig
-
Immunological memory provides the basis for __________ by___________ against diseases.
-
the act or process of becoming immune
immunization
-
vaccination
Vaccination is the administration of antigenic material (the vaccine) to produce immunity to a disease
-
AIDS stands for....
Acquired immunodeficiency syndrome
-
Another term for the AID virus
HIV - human immunodeficiency virus
-
What subpopulation of blood cells are invaded by the AIDS virus?
helper T (CD4) cells
-
What does the AIDS do to the helper T cells?
invades them and gradually kills them off
-
What happens to the B cells as the T cells are killed in AIDS?
the message to the B cells for producing antibodies is reduced to the point that there are no circulating antibodies to combat the HIV.
-
What happens to the AIDS virus when B and T cells are destroyed?
it is free to multiply at will
-
what do aids patients usually die from? Why?
opportunistic diseases
lack primary immune response to counteract even harmless diseases
-
well known cancer of blood and lymph
Hodgkin's disease
-
Signs and symptoms of Hodgkin's disease
- lymph nodes swell and are nontender
- fatigue
- weight loss
- pruritis
-
-
how is Hodgkin's disease usually treated? what is the prognosis?
- chemotherapy and radiation
- with treatment prognosis is good
-
name a few autoimmune diseases
- rheumatoid arthritis
- systemic lupus erythematosus
- Addison's disease
- Grave's disease
- MS
- Guillain-Barr syndrome
-
What are autoimmune diseases?
body's immune system develops a sensitivity to normal tissues and produces antibodies antibodies against them
-
Treatment for autoimmune diseases is generally ______________.
unsatisfactory
-
Drug treatment commonly used in treatment of autoimmune diseases
anti-inflammatories like prednisone
|
|
