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Flashcards in Vaccines Deck (86)
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1
Q

Immunisation

A

act of making someone. something immune to a particular disease

2
Q

Vaccination

A

deliberate induction of adaptive immune response by injecting a vaccine (dead or attenuated - nonpathogenic) form of the pathogen

3
Q

Immunological Memory

A

Ability of immune system to generate more rapid and more effective responses to antigens previously encountered

4
Q

Memory Cells (B cells)

A

initial expansion of antigen specific cells -
some progeny don’t divide or develop to plasma cells
revert to small lymphocytes with same BCR as ancstors

5
Q

Somatic hypermutation

A

alterations in variable regions of light and heavy chains of memory cells - random
increase affinity 1000x

6
Q

Features of memory B cells (6)

A
Long lived
Increased frequency
proliferate more rapidly
produce more antibody
produce higher affinity antibody
produce antibodies with better effector functions (IgG/IgA)
7
Q

Memory T cells features (3)

A

long lived
high frequency
proliferate more rapidly

8
Q

Memory T cells express

A

low levels of L-selectin not home to lymph nodes and so stay in circulation
CD450R associated with TCR and CD4 co-receptor
more effective transduce signal than naive

9
Q

Naive T cell express

A

CD45RA - not associate with TCR

10
Q

Vaccine must… (4)

A

Activate antigen presenting cells to process antigens and produce cytokines
Activate T and B cells, giving high yield memory cells
Generate T cells to several epitopes (parasite variation)
Provide constant and long lasting source of antigenin lymphoid tissue

11
Q

Natural active

A

natural infection

12
Q

Artificial active

A

immunisation

13
Q

Natural Passive

A

Placental transfer IgG

Maternal IgA - colostrol transfer

14
Q

Artificial Passive

A

human/animal IgG normal or immune
pooled specific immunoglobulin
animal sera (snake venom) anti- toxins/venoms

15
Q

Passive immunisation - Passive Transfer

A

transfer specific high titre antibody from immune donor to non-immune

16
Q

Passive Immunisation - Adoptive Transfer

A

transfer immune cells from immune donor

17
Q

Passive Immunisation

A

immediate

transient - only last up to 6 months

18
Q

Neonatal protection

A

trough at 3-6 months - decline maternal IgG, child’s still rising

19
Q

Active Immunisation - vaccine types (5)

A
Live attenuated
Killed
Sub-unit
Conjugate
Recombinant
20
Q

Requirements of effective vaccine (8)

A
Safe
High level protection
Long-lasting protection
Right response type (local/systemic) (Ab/CMI)
Low cost
stable
easy administration
minimal SE
21
Q

Killed Vaccine Examples (4)

A

Salk
Pertussis (Whooping cough)
Typhoid
cholera

22
Q

Killed vaccine features (3)

A

important antigens must survive
possible SE
use formaldehyde to kill

23
Q

Advantages of killed vaccine

A

stable in storage

not cause disease through residual virulence

24
Q

Live Vaccines examples (6)

A
Mumps
Measles
Rubella
Oral polio (sabin)
BCG
Yellow fever
25
Q

Live vaccines feature

A

cold attenuated

host range mutants

26
Q

Live vaccine positives (4)

A

single dose
natural route admission
local and systemic immunity
right response type

27
Q

Live vaccine negatives (4)

A

Reversion to virulence
contamination
susceptible to inactivation
disease in immunocompromised

28
Q

Recombinant sub-unit example

A
Hepatits B (first)
protect against natural infection
29
Q

purified sub-unit

A

purified component of pathogen

30
Q

purified sub-unit example

A

Haemophilus Influenza B –> meningitis or pneumonia
purified capsular polysaccharides
purified haemagglutinin and neuraminidase

31
Q

Conjugate example

A

Haemophilus vaccine conjugated to tetanus or diptheria toxoid

32
Q

Conjugate mechanism

A

b cell bind polysaccharide and internalise and present peptide to T cells, B cell produce relevant antibody

33
Q

Children not respond to polysaccharide antigen

A

link polysaccharide to protein (tetanus toxoid) to gain T cell dependent response
presents protein and stimulated to produce antibody to polysaccharide

34
Q

Right type of immunity

A

HIV –> CTL

more harm than good otherwise

35
Q

Cytosol - virus response

A

cytotoxic CD8

36
Q

Macrophage vesicles response

A

TH1

37
Q

Extracellular fluid response

A

TH2

38
Q

Adjuvants

A

enhance immune response
keep store of antigen in individual
immunostimulatory response
e.g. alum better for antibody than cell mediated

39
Q

NEW DNA vaccines

A

Injected with DNA encoding antigen

40
Q

DNA vaccine plasmid

A
antigen expression unit
produciton unit (amplification)
41
Q

Plasmid delivery (3) and best place

A

intradermal
intravenous
intramuscular
skin and mucous membranes best - high conc dendritic cells, macrophages and lymphocytes

42
Q

Gene Gun (biolistic)

A

sticky DNA to gold

accelerated by partial vacuum

43
Q

Gene pathway for DNA vaccine

A

transcribed and translated into peptide
binds MHC 1
presented to CD8+ T cell (virus)

44
Q

DNA vaccine into Dendrtic

A

CD4+ (T helper) and CD8+

45
Q

DNA vaccine advantages (6)

A
Induce humoral and cell mediated
antigens resemble native viral epitopes
Produced quick
Many differemt antigens in one dose
Improper folding not a problem
cheaper
46
Q

DNA vaccine Negatives

A

Cannot substitute for polysaccharide vaccines - outer caspid
extended immunostim –> chronic inflammation
some antigens require processing

47
Q

DNA tatooing

A

naked plasmid with thousands of punctures - multiple needle device
affects local cells in murine skin - strong specific response

48
Q

Dengue in mice

A

DNA vaccine used to immunise
Serum from immunised mice reacts with all 4 serotypes
inhibited infection of naive cells

49
Q

DNA vaccine looking to treat

A

cancer and virus

poor immunogenicity so far

50
Q

Dendritic cells

A

main APC - broad range of effector cells

important in tumour specific immune response

51
Q

Dendritic cells location and function

A

Immature - mucosal etc. - where efficiently phagocytose microbes, particulate antigens + take up soluble antigen
move to 2ndry lymphoid tissue and mature - present antigen to T cells

52
Q

DC Antigen take up

A

engulfment of apoptotic bodies
macropinocytosis
receptor mediated endocytosis (mannose and Fc - CD32/64

53
Q

DC source

A

CD34+ blood/bone marrow precursors

54
Q

Immature DC cultured with

A

IL-4 and GM-CSF

derived from monocytes

55
Q

Mature DC cultured with

A

IL-4, GM-CSF
derived from monocytes
with IL1beta, IL-6, TNFalpha and PGE2

56
Q

Antigen preparation

A

Peptides - specific
tumour lysates - many antigens - not prefer T helper
RNA transfection - many tumour epitopes to MHC I

57
Q

Objective response rate

A

disease not progressed

58
Q

CBR

A

Clinical Benefit Ration - objective response and stable disease

59
Q

Trials into

A

glioma, melanoma

prolong life

60
Q

Interstitial DC induce

A

ig secreting plasma cells and trigger diff of follicular helper T cells

61
Q

Langerhan cells induce

A

cytotoxic CD8+ T cells

62
Q

Reverse Vaccinology

A

genome sequence used to predict proteins location in organism surface - make protein - see response

63
Q

Advantages of Reverse Vaccinology (5)

A
fast
use organisms can;t grow
rare antigens identified
antigens not in-vitro
non-structural proteins
64
Q

Disadvantage of Reverse Vaccinology

A

Not use non proteinous antigens

65
Q

Benign pre-malignant melanomas in cervial cancer

A

CIN - cervical intraepithelial neoplasia

1-3 in severity

66
Q

HPV vaccine

expensive

A

18 types associated with cervical cancer

67
Q

HPV vaccine manufacture (2)

Gardasil

A

DNA free virus like particles VLP in yeast

express major caspid antigen L1 - strong response

68
Q

HPV only works

A

prior to infection

69
Q

HPV possible SE

A

Make room for similar viruses

70
Q

Malaria (4)

A

Plasmodium species - protozoa, apicomplexa
Transmitted by female anopheles mosquito
sexual stage - mosquito
asexual stage - vertebrate host - infect 4 species

71
Q

Plasmodium falciparum

A

most common

more fulminent - coma and renal failure

72
Q

Malaria symptoms

A

headache, muscle ache, lethargy
fever - temp rise - shivering
lasts 30 minutes returns 48hrs
spleen and liver enlarge + anaemia

73
Q

Malaria can relapse

A

store in liver

vivax and ovale

74
Q

Malaria - pregnant

A

anaemia and reduced birth weight

death more common

75
Q

Cerebral malaria (3)

A

sudden coma
can be fatal
can be more common in healthy

76
Q

Falciparum fatal

A

cross blood brain barrier

77
Q

Malaria lifecycle (5)

A
sporozoites travel to liver
propagate in hepatocytes --> shizonts
release merazoites - infect erythrocytes
asexual reproduction in blood
lysis of erythrocyte and infect RBC
78
Q

Malaria life cycle sexual stage (4)

A

Merazoites form male and female gametoytes - circulate
taken up in new mosquito
fuse into zygote and penetrate gut membrane –> oocyst
divides and release sporozoites - travel to salivary gland

79
Q

Different vaccine (3)

A

Pre-erythorcyte - block stages in hepatocytes
Blood stage - no disease, organisms still present
Transmission blocking - works in mosquito

80
Q

Pre-erythocytic vaccine

A

protect and prevent invasion (30mins)
radiation-attenuated sporozoites
CD8+ Tcell response

81
Q

Blood Stage Vaccine

A

Stops symptoms

work on naive population not one already exposed

82
Q

Transmission Blocking Vaccine

A

Target sexual stage specific molecules
not yet effective enough
conjugate - detoxified exoprotein act as adjuvant

83
Q

HIV Vaccine types being developed (not essential)

A
peptide epitope
DNA
recombinat viral protein 
live vector
pseudovirions
84
Q

Tuberculosis Vaccine

A

BCG - live attenuated - mycobacterium bovis

good in children

85
Q

Blocking hypothesis

A

prior sensitisation to prior mycobacterium provide protection
but not against TB
and impairs BCG

86
Q

Ideal new TB vaccine

A

Given at birth
transmitting blocking - decrease sputum smears
therapeutic vaccine used with therapy - shorten treatment
induce strong cell mediated