Chapters 5 Flashcards
(40 cards)
1
Q
Innate Immunity
A
- Nonspecific
- Defenses against infection that are ready for immediate activation prior ro attack by a pathogen
- Rapid
- Includes physical, chemical, & cellular barriers
- Activation of Phagocytes
- Inflammation
- Works with adaptive
- Antibody Independent
2
Q
Adaptive Immunity
A
- Acquired
- Induced by exposure to microbes & counters infection with a SPECIFIC response with B & T cells
- Memory
- Anitbody Dependent
3
Q
PRRs can detect what?
A
- Aging cells
- Dead cells
- Damaged cells
4
Q
Pathogen-Associated Molecular Patterns
A
- Sugar, proteins, lipids, nucleic acids, or a combination
- PAMP binding immoblizes infectious organism
- May lead tophagocytosis
- PRR engagement leads to host activation
5
Q
Endotoxin
A
LPS on gram-negative bacteria
6
Q
Peptidoglycan
A
Recognized by NOD proteins
7
Q
What receptors recognize Peptidoglycan & LPS?
A
TLR 2 & TLR 4
8
Q
TLRs
A
Toll-Like Receptors
- Mediate recognition of diverse pathogens
- Cytokine activation
- Promote Inflammation
- Recruit WBCs
- Scavenger Receptors
- Opsonins
9
Q
Opsonins
A
Any molecule that enhances phagocytosis by marking an antigen for an immune response
10
Q
Scavenger Receptors
A
- Involved in binding modified low-density lipoproteins, some polysaccharides, and some nucleic acids
- Internalization of bacteria & phagocytosis of host cells
11
Q
MICA & MICB
A
Stress signals on cancer cells
12
Q
Soluble Defense Mechanisms
A
- Protection from viral infection
- Lytic destruction of microbes
- Increasing susceptibilty of microbes to ingestion by phagocytes
13
Q
Type I Interferons (IFNs)
A
- Soluble means of self defense
- IFN-alpha produced by dendritic cells
- IFN-beta produced by non-leukocytes, such as fibroblasts
- Produced in response to viral infections
- induce both antiviral & apoptotic pathways
14
Q
Microcidal Molecules
A
- Cysteine-Rich Peptides = defensins
- Form channels in cell membranes of bacteria
Neutrophils are defensin-rich
15
Q
The Complement System
A
A group of serum proteins circulating in inactive form
16
Q
Outcomes once the Complement System is activated
A
- Target cell membrane lysis
- Inflammation
- Chemotaxis
- Opsonization to enhance phagocytosis
- Clear immune complexes from circulation
- Secretion of immunoregulatory molecules
17
Q
Complement Activation
A
- Alternative Pathway (Innate Immunity)
- Mannan-Binding Lectin (MBL) Pathway (Innate Immunity)
- Classical Pathway (Adaptive Immunity)
18
Q
The Terminal or Lytic Pathway
A
- Entered from alternative, MBL, or classical pathway
- Attachement of C5b to bacterial membranes initiates membrane attack complex (MAC)
- MAC = cell lysis
- Unregulated flow of electrolytes
19
Q
Mannan-Binding Lectin (MBL) Pathway
A
- Lectins are proteins that bind to specific carbohydrates
- Activated by MBL binding to mannose-containing residues of glycoproteins on certain microbes
- Can interact with MBL-activated serine protease (MASP)
20
Q
Anaphylotoxins
A
- Attract & activate different types of leukocytes
- Small fragments
- C5a > C3a >= C4a
21
Q
Cytokines
A
- Secreted by WBCs & other cells
- Involved in innate, adaptive, & inflammation
- Antigen-nonspecific
22
Q
Chemokines
A
- Subgroup of cytokines
- Involved in chemotaxis of WBCs
23
Q
Interleukin-1 (IL-1)
A
Acts on Vascular Endothelium
24
Q
Interleukin-6 (IL-6)
A
Acts on Liver
25
Interleukin-8 (IL-8) [Chemokine]
Acts on Vascular Endothelium
26
Interleukin-12 (IL-12)
Acts on NK Cells
27
Tumor Necrosis Factor-alpha (TNF-alpha)
Acts on Vascular Endothelium
28
Phagocytosis
Engulfment & degradation of molecules
29
Destruction of Ingested Microbes by
* Lysosomal hydrolases
* Toxic Oxygen Species
* Nitrous Oxide
* Low pH
30
Secretion of IL-1 & IL-6
Elevate temperature
31
Secretion of TNF-alpha
Increase vascular permeability
32
Secretion of IL-8 & IL-12
Attract & activate WBCs (Neutrophils & NK Cells)
33
NK Cells Responses
* Binding KAR to MICA & MICB generates a kill signal
* KIR assesses MHC-I on target
34
Early Components of Inflammation include:
* Increased vascular permeability
* Recruitment of neutrophils & other lwukocytes fromthe blood to the site of damage/infection
35
Cardinal Signs of Inflammation
* Pain
* Heat
* Redness
* Swelling
* Loss of Function
36
Cell Types of the Innate Immunity
* Neutrophils
* Macrophages
* Dendritic Cells
* NK Cells
37
Neutrophils
* **Phagocytosis**
* Reactive oxygen & nitrogen species
* Antimicrobial peptides
38
Macrophages
* **Phagocytosis**
* Inflammatoy mediators
* Antigen Presentation
* Reactive oxygen & nitrogen species
* Cytokines
* Complement proteins
39
Dendritic Cells
* Antigen presentation
* Costimulatory signals
* Reactive oxygen species
* Interferon
* Cytokines
40
NK Cells
* **Lysis of viral-infected cells**
* Interferon
* Macrophage activation
