Immunology Olivia

Front 1

understand the concept of host pathogen relationship

Back 1

commensalism-mutual, no effect on host.
colonisation, persistance, disease becomes parasitic relationship; detrimental to host, beneficial to parasite. both host and pathogen have evolved mechanisms to evade eachother's responses

Front 2

list the major defence mechanisms that limit extracellular infection

Back 2

phagocytosis
opsonising antibodies
antibody complement
mast cells and eosinophils
cross linking IgE

Front 3

how do extracellular pathogens evade the immune system?

Back 3

molecular mimicry
avoid phagocytosis by restricting phagocyte chemotaxis ie pertussis toxin
inhibit binding of Fc portion ie Staphyloccocus A protein
produce toxin to kill phagocytes
capsule/biofilm polysaccharide coat resists opsonisation

Front 4

where do intracellular pathogens hide in the cell?

Back 4

cytosol or phagosomes

Front 5

why are Th1 CD4+T-cells so important in attacking intracellular infection?

Back 5

Because Th1 cells secrete IFN gamma which activates macrophages. macrophages are crucial for fighting intracellular infection.

Front 6

why are CD8+T-cells important in fighting some intracellular infections?

Back 6

MHC class 1 molecules present endogenous proteins i.e. viruses, bacteria etc to CD8+T-cells, CD8+ T-cells therefore are needed to recognise some endogenous cytosolic antigens

Front 7

how do macrophages kill intracellular pathogens?

Back 7

by reactive nitrous oxide and oxygen species.

Front 8

list functions of IFN gamma

Back 8

-primes production of reactive N and O2 species
- forces phagolysome formation
-increases MHC class I and II expression
-induces iron deprivation and acidification of phagolysome.
-increases costimulatory molecules

Front 9

which two cells secrete IFN gamma

Back 9

NK cells
Th1 cells

Front 10

outline the lifecycle of a virus and the mechanisms of the host immune system to counteract these events

Back 10

1. virus attachs to cell, antiodies and complement try to prevent this
2. virus enters cell cytosol
3. viruses begin to replicate inside host cell, IFNs interfere with replication by recognition of PAMPS i.e dsRNA
4. viruses eventually leave cell to infect new cells, dendritic cells attempt to catch them, NK cells limit immune evasion by secreting IFN gamma, granzymes, perforin etc. CD8+T-cells induce apoptosis in virally infected cells

Front 11

what public health measures apart from vaccination increase overall health in a society

Back 11

clean water
good hygiene practices
antibiotics
vector control (insects, rodents)
safe sewage disposal
avoid overcrowding

Front 12

what are the aims of immunisation?

Back 12

protection of individual and community
prevention of serious disease and death
containment of disease outbreak
elimination of specific diseases

Front 13

explain toxoid vaccines

Back 13

used to immunise against bacterial disease the vaccine contains antitoxins that lead to development of inactivated toxin a toxoid. toxoid vaccines are safer but induce a weaker immune response and require multiple doses

Front 14

what type of antibodies is the recipient of a toxoid vacccine generating?

Back 14

neutralising antibodies i.e IgG

Front 15

what were the first two live vaccines for humans?

Back 15

rabies and tuberculosis

Front 16

explain the initiation of in vitro vaccine culture

Back 16

in 1931 it was discovered that a fertile hen's egg could be used as a culture for vaccine production. a cheaper and safer alternative.

Front 17

what is EPI?

Back 17

Expanded Program on Immunisation launched by WHO Aim was to achieve maximum disease control with high levels of immunization coverage with greatest number of countries

Front 18

describe hypersensitivity reaction types

Back 18

type I- allergic reaction, Th2, IgE mast cells eosinophils
type II- cytotoxic antibody dependent IgM IgG
type III- immune antigen-antibody complex IgM IgG
type IV- delayed type hypersensitiviy- Th1- IL-2, IFN gamma = macrophages, CD8+T-cells

Front 19

which diseases are covered by EPI?

Back 19

tuberculosis
DTP (diptheria,tetanus pertussis)
polio
measles