organization of the Immune system Flashcards
(29 cards)
430 BC: Plague in Athens
Historian Thucydides wrote: “Only those who had recovered from the plague could nurse the sick because they would not contract the disease a second time”
variolation
Reports suggest that the dried crusts derived from smallpox pustules were either inhaled or inserted into small cuts in the skin (a technique called variolation ) in order to prevent this disease.
small pox is caused by
variola major
Edward Jenner 1798
cowpox injection can stop small pox infection
Louis Pasteur
The induction of immunity to Cholera.
Pasteur hypothesized that aging had weakened the virulence of the pathogen and that such a weakened or attenuated strain could be administered to provide immunity against the disease.
He called this attenuated strain.
Vaccine
(from the Latin vacca, meaning “cow”), in honor of Jenner’s work with cowpox inoculation.
Louis Pasteur In 1881
In 1881, Sheep and Bacillus anthracis
Pasteur 1885
In 1885, Pasteur administered his first vaccine to a human, a young boy who had been bitten repeatedly by a rabid dog, was inoculated with a series of attenuated rabies virus preparations.
Elie Metchnikoff In 1883,
Metchnikoff hypothesized that cells, rather than serum components, were the major effectors of immunity
PHAGOCYTOSING CELLS
Elvin Kabat, in 1930,
soluble components in serum could neutralize or precipitate toxins and could agglutinate (clump) bacteria
hummoral immunity
Because these antibodies were contained in body fluids (known at that time as the body humors ), the immunologic events they participated in was called
Humoral immunity
passive immunity
This form of immune protection that is transferred between individuals is called passive immunity
Advantage:
Quick solution
Disadvantage:
Short-lived
Active immunity
Active immunity: Administration of a vaccine or natural infection in the host
antigen
antigen – any agent (molecule) that binds to components of the immune response – lymphocytes and their receptors – antibodies and the TcR.
immunogen
immunogen – any agent capable of inducing an immune response.
hapten
hapten – is antigenic but not immunogenic unless it is attached to a carrier molecule of some sort which supplies the immunogenicity.
The cells and molecules of the immune system become activated in a given immune response depend on:
The chemical structures present on the pathogen.
Whether it resides inside or outside of host cells.
The location of the response.
The process of pathogen recognition involves an interaction between ?
The process of pathogen recognition involves an interaction between the foreign organism and a recognition molecule (or molecules) expressed by host cells.
Ligands for recognition molecule are
whole pathogens
antigenic fragments
or products secrected by foreign organism
Pathogen-
Pathogen- associated molecular patterns (or PAMPs) are:
Common foreign structures that characterize whole groups of pathogens.
Unique antigenic structures that the immune system frequently recognizes first.
(PRRs)
pattern recognition receptors (PRRs) detect and destroy PAMP in genomic DNA germline encoded conserved 1st line of defense
tolerance.
This principle, which relies on self/nonself discrimination, is called tolerance.
Innate immunity
Built-in molecular and cellular mechanisms that are encoded in the germline
Evolutionarily more primitive
Aimed at preventing infection or quickly eliminating common invaders
Innate Immunity examples
Physical and chemical barriers to infection
DNA-encoded receptors PPRs
Preexisting serum proteins called Complement
Adaptive immunity
Adaptive immunity
More molecular differences.
Relies on B and T lymphocytes.
Takes longer to come on board but is much more antigen specific (within 5 or 6 days after the barrier breach and initial exposure)
