Vaccines Flashcards
macrophage, dendritic cell, langerhans cell and B lymphocyte are all forms of…
APC
cytokines associated with TH1 responses
IL-2, IFN-y, TNF
cytokines associated with Th2 responses
IL-4,5,6
antigen used in influenza vaccine
HA hemagluttinin - receptor binding glycoprotein
time taken post-imm to be protected against influenza
7 days, lasts 6mo
Naive T cell marker
CD45 RA+ve (nAive)
Memory T cell marker
CD45 RO+ve (memOry)
Mature B cell marker
CD19
T cell function tests
in-vivo type Iv hypersensitivity tests - i.e Mantoux
in-vitro T cell proliferation studies
B cell function tests
serum Ig levels
specific Ig levels
3 characteristics that make memory cells different to naive cells (broad)
- more aggressive response with subsequent exposures - proliferation, activation and high affinity receptors
- different pattern of cell surface markers to allow different levels of adhesion and chemotaxis - entry to non-lymphoid tissue
- longevity without antigen as they have low level proliferation (like stem cells) in response to cytokines
majority of CD4+ cells
Central memory T cells
Majority of CD8+ cells
Effector memory T cells
CCR7- and CD62L low
Effector memory T cells
CCR7+ and CD67L high
Central memory T cells
binds to CCL19 and 20 on lymph node endothelial cells to allow for extravasation into the lymph node.q
CCR7
interacts with molecules in the High endothelial venules to allow migration and rolling –> travel to other LN via lymphatic system
CD62L high
found in the liver and lungs, produce IFN-Y and perforin
effector memory cells
found in lymph nodes and lymphatic system, produce IL-2
central memory cells
live vaccines
MMR, BCG, polio (sabin), vaccinia, yellow fever, VZV, typhoid, rotavirus, intranasal influenza
inactivated vaccines
influenza, cholera, polio (salk), pertussis, HepA, rabies
toxoid vaccines
tetanus diptheria
subunit vaccines
HepB (HbsAg)
HPV (capsid)
Influenza (HA/NA)
conjugate vaccines
Hib
meningococcus
pneumococcus
primary adjuvant in humans
Alum
how does alum work
absorbs ag and promotes slow steady release
primes naive b cells
primes adaptive immune responses
decreased effectiveness of vaccination in the elderly is due to:
- immune senescence
2. nutrition
3 advantages of live vaccines
- establishes infection –> often lifelong immunity
- stimulates all phases of immune response
- durable and cross reactive
3 disadvantages of live vaccines
- safety - reversion to virulence, spread to unvacc
- cant use in immunocomp
- storage - cold chain
disadvantages of inacitvated/component vaccines
- not as immunogenic
- multiple doses usually needed
- adjuvants usually needed
