Immunity- Immune Defense Mechanisms
active immunization
Ag preparations given to person requires person to form an immune system takes time to develop long lasting used as a preventative
t-helper cells
CD-4
attachment of phagocytic cells
PAMPS on microbe bind to various receptors on phagocyte surface
inflammation
a complex response involving cells and chemicals released by cells
inflammation
a response of tissue to injury
antibody (Ab)
a serum protein produced by the immune system in response to the presence of a specific antigen
antigen (Ag)
a substance which can stimulate the immune system of an animal which reacts specifically with lymphocytes or their products
natural immunity
acquired through the normal life experiences not included through medical means
cytotoxic t cells
activation of t cells requires help from other cells (antigen presenting cells)
passive immunization
administration of antibody molecules does not require person to form an immune system works immediately but short lasting used primarily as a treatment
B-lymphocytes
antibody (IgD)
opsonization activation aggultination neutralization of viruses precipitation of cell free molecules
antibody on surfaces of immune system effector causes:
IgM
antibody produced during primary response
IgG
antibody produced later in infection
immune system effectors
attaches to surface of pathogen due to anitbodies specificity for antigen pathogen surface becomes coated with antibody
chemotaxis
attraction of phagocytic cells to area
antibody mediated response
b lymphocytes
t-helper cells
bind to antigen and class 2 MHC on APC's
toxoid vaccines
chemically denatured pathogen toxin non-toxic and stimulates immune response
interferons
chemicals produced and secreted by white blood cells and certain tissue cells in response to a viral infection
subunit vaccinations
contain only antigenic portion of microbe; only one used
effector of cell mediated response
cytotoxic T cells (CD-8 cells or CTLs)
activated lymphocytes
divide-mitosis produced antibody specific to the antigen (Ab producing cell= plasma cell)
antigen presenting cells
engulf entire pathogen-> digests pathogen-> processes antigen-> presents antigen on its surface
immune response curve
explains how the immune system reacts to Ag over time helpful for understanding how active immunization functions
advantages of subunit vaccinations
few adverse reactions good to excellent immune response
dendritic cells
found in skin and several other organs; connective tissues
TH2
helps B-lymphocytes
TH1
helps cytotoxic (CD-8) cells
MHC
helps get antigen stuck on surface of host cell
disrupt cell membrane disrupt metabolism initiate apoptosis
how lymphotoxins act on infected cell/pathogen
vasodilation and increase vascular permeability chemotaxis pain
important actions of inflammatory mediators
neutrophils
in the blood stream but move out into the tissues; shortest living
macrophages
in various organs and lymphoid tissue throughout the body; longest living
five cardinal signs of inflammation
injury rubor, calor tumor dolor pain
stimulate phagocytic cells, T and B cells slow viral replication in infected host cells inhibit cancer cells
interferons act to...
antigens
large complex organic molecules usually proteins or molecules containing proteins foreign substances molecules found on surface of pathogen
IgG
long term immunity, memory antibodies
T-independent
lymphocytes recognize Ag by itself
recognize
lymphocytes_____________ pathogens by binding to antigens
phagolysozome
lysozome travels to phagozome and dumps chemicals in it
complement system
made up of about 25 proteins that work together to assist the action of antibodies in destroying bacteria
acquired (adaptive or specific) immunity
mainly developed/acquired after birth works against many types of microbes specific mechanisms are not active immediately
key cell of inflammation
mast cell
primary response
memory cells are produced no antibody production
secondary response
memory response
chemical barriers
mucus lysozyme stomach acid
skin
multiple layers of cells outer layer; dead cells with protein and lipid layer
phagocytic
neutrophils macrophages dendritic cells
disadvantages of subunit vaccinations
newer vaccines are expensive
how cytotoxic cells work
once bound to infected cell or large pathogen, lymphocyte produces chemicals called lymphotoxins
direct killing of microbes stimulate inflammation opsonization
once the complement system is activated it will..?
live/ attenuated immunizations
pathogen made avirulent by modifying growth conditions in the lab antigen intact and pathogen capable of replicating
killed/inactivated immunnization
pathogen subjected to chemical or radiation treatment antigens intact but pathogen destroyed
latent period
period of immune response curve that lasts 10-15 days
examples of subunit vaccinations
pneumoccocus, HIV, Hepatitis B
examples of live/ attenuated immunizations
polio, measles, mumps, rubella
disadvantages of live/ attenuated immunizations
possible mild symptoms might revert back to virulent form transmissible
passive immunizations
post exposure preventative treatment for disease
innate (inborn or non-specific) immunity
present at birth effective against many types of microbes no specificity works immediately or very quickly
examples of killed/inactivated immunizations
pretussis, typhoid, cholera
antibody mediated response
primary defense against extracellular pathogens effector= antibody molecule
cell mediated response
primary defense against intracellular pathogens
advantages of live/ attenuated immunizations
produce strong immune responses less adverse reactions
IgM
produced at first response to antigen; can serve as a B-cell receptor
lymphokines
produced from t-helper cells which stimulate other lymphocytes
artificial immunity
produced purposefully through medical procedures
immune avoidance mechanisms
rapid reproduction
once cytotoxic t cells are activated
recognize t cells with intracellular pathogens. infected host cell has Ag on surface associated with class I MHC molecule
mast cell
release inflammatory mediators
function of phagocytic cells
removal of foreign particles also interacts with the acquired immune system
T-dependent
require help of t-lymphocytes
disadvantages of killed/inactivated immunizations
requires larger dose or more frequent application adverse reactions- soreness, swelling- to other materials in vaccine
advantages of killed/inactivated immunizations
safe- can't produce symptoms of disease
why don't you get the disease again?
secondary response
which response is the best?
secondary response, no latent period
IgA
secretory antibody; on mucous membranes
antibody classes
size and shape varies produced and found in certain locations in the body all have the same basic function- to bind to specific antigen
physical barrier
skin
antibody mediated response
specific B lymphocytes-> recognize specific antigens-> produce specific antibody
cell mediated response
specific t-lymphocytes-> recognize specific antigens -> lymphocytes become activated
antigens
stimulater of the immune system
T-lymphocytes
t cell receptor (Ag)
cell mediate response
t lymphocytes
examples of toxoid vaccines
tetanus, diphtheria
active immunity
the consequence of a person developing his own immune response to a microbe
passive immunity
the consequence of one person receiving preformed immunity made by another person
lymphocytes
the primary cells of the adaptive immune system present in the blood stream and lymphoid tissue which react to the presence of specific antigens
opsonization
to make bacteria more susceptible to the action of phagocytes
function of inflammation
to promote healing of damaged tissue
phagozome
vesicle that contains microorganisms that contains degradative enzymes
memory cell
what cell is introduced during immune response curve?
primary response
what happens after first exposure to antigen
secondary response
what happens when exposed to antigen later in life
macrophages neutrophils dendritic cells
where are phagocytes found?
