Immunity to Infection Flashcards
1
Q
Typical course of infection
A
- establishment of infection
- induction of adaptive response
- adaptive immune response
- immunological memory
2
Q
Stages of infection
A
- local infection
- infection of tissues
- lymphatic spread
- adaptive immunity
3
Q
Happenings at the lymph node
A
- B cells enter through HEV and migrate to primary follicle
- Ag-specific B cells trapped at border between T zone and follicle
- prolif B cells form a primary focus
- several B cells migrate to nearby follicle and form a GC (rapid prolif and somatic mutation)
4
Q
Describe T cell homing
A
- skin-homing lymphocytes bind E-selectin and CCL17 on vascular endothelium
- keratinocytes express CCL27, which bings CCR10 on skin-homing effector T cells
5
Q
Functions of Antibodies
A
- neutralization (toxins)
- opsonization (extracell bacteria)
- complement activation (plasma bacteria)
6
Q
Early events at site of Leishmania infection
A
- mosquito bites
- increased chemokines
- neuts release cytokines and chemokines
- attract mast cells, NK cells, DCs and macs
7
Q
Role of neuts in Leishmania infection
A
- Leishmania-mediated neutrophil recruitment
- immunopathology
- transient host
- paraciticidal effect
- immunoregulation
8
Q
Neutrophil modes of killing
A
Phagocytic clearance
- resp. burst (ROS)
- release of preformed lytic enzymes
- release of inflam mediators
- release of defensins
Catch microbes by Neutrophil Extracellular Traps (NETS)
9
Q
Sequence of NETosis
A
- stim of neut receptors
- neuts adhere to substrate and mobilize granules
- histones in nucleus get processed and intracell membr disintegrate
- cell membr ruptures, mixture of cytoplasm and nucleoplasm gets expelled
10
Q
Balb/c mice
A
Skewed to Th2 (susceptible to Leishmania)
11
Q
C57BL/6 mice
A
Skewed to Th1 (resistant to Leishmania)
12
Q
Factors influencing functional differentiation of CD4 T cells
A
- Ag structure
- route of admin of Ag
- genetic background
- types of APCs
- costim. signals
- cytokine environment
13
Q
Action of DCs in absence of infection
A
- make TGF-B but little IL-6
- CD4 cells activated to express Foxp3 and induce T regs
- inhibits Th1 and Th2
14
Q
Action of DCs in early infection
A
- DCs express high IL-6 and high TGF-B
- CD 4 cells express RORyt and become Th17
15
Q
How to rescue Balb/c mice
A
- give anti-IL-4
- skew to Th1
