Exam 1 - Innate Immunity: Inflammation, Infection, & Wound Healing Flashcards
1
Q
What is the purpose of physical barriers?
A
To prevent injury
2
Q
Where can physical barriers be found in the body?
A
- the skin
- lining of the gastrointestinal tract
- lining of the genitourinary tract
- lining of the respiratory tract
3
Q
What are some examples of mechanical barriers?
A
- sloughing off of cells
- coughing and sneezing
- flushing
- vomiting
- mucus
- cilia
4
Q
How do physical barriers work in defense?
A
By mechanically removing infectious microorganisms
5
Q
How do biochemical barriers work?
A
Secrete substances to trap / destroy microorganisms
6
Q
What are examples of biochemical barriers?
A
- synthesized and secreted saliva, tears, ear wax, sweat, and mucous
- antimicrobial peptides
- normal bacterial flora
7
Q
How does normal bacterial flora act as a biochemical barrier?
A
- help get rid of toxins by knocking off “bad” bacteria
- don’t allow room for the “bad” bacteria
8
Q
What are 4 main factors about the inflammatory response?
A
1- Occurs in tissues with blood supply
2- Is activated rapidly after damage occurs
3- Depends on activity of both cellular and chemical components, including plasma and protein
4- Is non-specific
9
Q
How is the inflammatory response non-specific?
A
It takes place in the same way regardless of the type of stimulus or whether exposure to the same stimulus has occured in the past
10
Q
What type of defense is the inflammatory response?
A
A second line of defense
11
Q
What are examples of injury that can activate the inflammatory response?
A
A variety of materials including: - Infection - Mechanical damage - Ischemia - Nutrient deprivation - Temperature extremes - Radiation Etc.
12
Q
What are other names for Local manifestations?
A
Clinical manifestations
Signs and symptoms
13
Q
What are other names for signs and symptoms?
A
Local manifestations
Clinical manifestations
14
Q
What are other names for clinical manifestations?
A
Local manifestations
Signs and symptoms
15
Q
What does ischemia mean?
A
A tissue or area does not have good blood flow
16
Q
What are the local manifestations of inflammation?
A
- redness
- heat
- pain
- swelling
- loss of function
17
Q
What is another name for redness?
How do you spell it?
A
Erythema
18
Q
What is a big reason patients go into shock?
A
Vascular permeability during the inflammatory response
19
Q
What are the microscopic changes that occur during the inflammatory response?
A
- Vascular response
- Increased vascular permeability
- WBC adherence
20
Q
What occurs during the vascular response of inflammation?
A
Vasodilation
21
Q
What symptoms does the vascular response cause during inflammation?
A
Vasodilation = more blood = more ERYTHEMA
More blood flow = more HEAT
22
Q
What symptoms occur due to vascular permeability?
A
Leads to SWELLING, ERYTHEMA, and HEAT
23
Q
What does increased vascular permeability mean?
A
Cellular walls become more flexible and they allow substances to freely move in and out of the cell
24
Q
What is the purpose of WBC adherence during the inflammatory response?
A
Provide some foundation work for clotting
Start to clean up the injury
25
What occurs during the vascular response of inflammation?
- Blood vessel dilation
- Increased vascular permeability and leakage
- White blood cell adherence to the inner walls of the vessels and migration through the vessels
26
What are the goals of inflammation?
- Limit and control the inflammatory process
- Prevent and limit infection and futher damage
- Initiate adaptave immune response
- Initiate healing
27
How does inflammation initiate healing?
Through removal of bacterial products, dead cells, etc.
28
How long does it take for microscopic changes to occur during the inflammatory response?
They occur within seconds
29
What is acute inflammation?
- Inflammation with a nonspecific protective response to cellular injury
- Has a rapid onset
30
Where does acute inflammation occur?
Only in vascularized tissue
31
What are the macroscopic hallmarks of acute inflammation?
- Redness
- Swelling
- Heat
- Pain
- Loss of function
32
What are the microscopic hallmarks of acute inflammation?
Accumulation of fluid and cells (edema)
33
In order to have a vascular response, what type of tissue must it take place in?
Must have good blood flow
34
What causes the start of the acute inflammatory response, after injury?
ACTIVATION of plasma systems
35
What plasma systems are activated during the acute inflammatory response?
- the Complement system
- clotting
- Kinin
36
What occurs at the same time as the activation of plasma systems during acute inflammatory response?
** Vasodilation
Also,
- Mast cell degranulation
- Release of cellular products
37
What is the first clotting factor?
Kinin
38
What does kinin do?
Builds the fiber that is the basis for the clot
| Activate and assist the inflammatory cells
39
What symptom(s) does vasodilation cause?
Redness, heat
40
What symptom(s) does vasular permeability cause?
Edema
41
What symptom(s) does cellular infiltration cause?
Pus
42
What symptom(s) does thrombosis cause?
Clots
43
What symptom(s) does stimulation of nerve endings cause?
Pain
44
What are mast cells? Where are they located?
Cellular bags of granules located in the loose connective tissues close to blood vessels
45
What occurs when the cellular bags of mast cells open?
- degranulation
| - release of chemicals
46
What are examples of where mast cells are located?
- Skin
- Digestive lining
- Respiratory tract
47
What causes the activation of mast cells?
* Physical injury
- chemical agents
- immunologic processes
- toll-like receptors (TLRs)
48
Biochemical mediators first released from mast cells during inflammation:
1- Histamine
| 2- Chemotactic factors
49
What are examples of chemotactic factors, and where do the chemotactic factors come from?
- neutrophil chemotactic factor
- eosinophil chemotactic factor of anaphylaxis
(ECF-A)
Found in mast cell granules
50
What is histamine?
A vasoactive amine
51
What does histamine do?
- Causes temporary, rapid constriction of the large blood vessels
- Causes dilation of the postcapillary venules
- Causes retraction of endothelial cells lining the capillaries
52
What is the first chemical released during the inflammation process?
Histamine
53
Why is histamine so helpful during the inflammatory response?
Causes constriction which:
- keeps inflammation localized
- keeps inflammation in as small of an area as possible
- keeps blood pressure balanced
54
What is the general function of Histamine’s H1 receptor?
Promotes inflammation
55
What is the general function of Histamine’s H2 receptor?
- Anti-inflammatory
| - Suppression of leukocye function
56
Where is Histamine’s H1 receptor located?
| What does it do there?
- Smooth muscle cells of the bronchi
| - Cause bronchi to contract
57
Where are Histamines H2 Receptors located?
| What do they do there?
- Parietal cells of the stomach mucosa
| - Induces secretion of gastric acid
58
How do H2 blocker medications work? (Antacids)
Block the H2 receptor from making acid
59
What is chemotaxis?
Directional movement of cells along a chemical gradient formed by a chemotatic factor
(Something that attracts cells - acts like a pheromone)
60
Function of neutrophil chemotatic factor
Attracts neutrophils
61
Function of eosinophil chemotactic factor of anaphylaxis
Attracts eosinophils
62
What does eosinophil chemotactic factor of anaphylaxis have to do with anaphylaxis?
Eosinophils have to do with allergic reactions
63
What ECF-A stand for?
Eosinophil chemotactic factor of anaphylaxis
64
What are the chemotactic factors released during mast cell degranulation?
- Neutrophil chemotactic factor
- Eosinophil chemotactic factor of anaphylaxis
(ECF-A)
65
What mediators are released from mast cells later in the inflammation process?
- Leukotrienes
- Prostaglandins
- Platelet-activating factor
66
What are leukotrienes and what do they do?
- Product of anachidonic acid from mast cell membranes
- Slow down the inflammatory process so it lasts longer through the healing process
- Mimics histamine in later stages
67
Function of prostaglandins
- Induces pain
- They are the product that causes us to feel pain (NOT INJURY)
- Mimics histamine in later stages
68
Lipid mediators released during the break down of mast cells:
- Leukotrienes
- Prostaglandins
- Platelet-activating factor
69
What causes pain in the inflammatory process?
Prostaglandins
70
What is platelet-activating factor?
- The chemical that causes platelet activation
71
What products are at work during the clotting process and what do they do?
1st- Kinin: initiates the clotting process
2nd- Platelet-activating factor: Chemical that causes platelet activation and strings platelets together to form clot (this is what causes the second layer of the clot and is what actually causes the clot to form)
(WBCs provide the first layer)
72
What are the early microscopic signs of inflammation?
- Permeability
| - Vasodilation
73
What are the early signs and symptoms of inflammation?
Erythema and heat
74
Cause all the hallmarks of inflammation:
- Mast cell products
75
Function of histamine: dont study this
- Dilation of blood vessels, slowing circulation in nearby vessels
- Causes endothelial cells to change shape and open intercellular junctions (allows fluid to leak from blood into tissue)
76
What results from increased blood flow and vasodilation?
- Increased redness and warmth
| - Increased permeability results in local swelling from increased fluid in the tissues
77
What are released later on in the inflammatory process? What do they do?
Lipid mediators (leukotrienes, prostaglandins, and platelet activation mediators) are released and continue the inflammatory process through histamine-like effects and cause pain
78
Name the plasma protein systems
Complement system
Coagulation system
Kinin system
79
Function of the compliment cascade
- Eliminate pathogens or toxins
- Activates every component of the inflammatory resonse
- Generates anaphylactic-toxic fragments that target cell lysis (break up cells)
In general,
- Antibodies hook onto pathogens
- Released to clean up spread of injury and get rid of any unwanted bacteria
80
What is the lectin cascade?
- Bacterial toxins related to carbohydrates
| - Carbohydrates are used to destroy toxins
81
What is the alternate cascade?
- Use carbohydrates to destroy all remaining bacterial debris
82
What are clots made of?
- Platelets & fibrin
| Way more fibrin than platelets when looking under microscope
83
Another name for the coagulation system
Clotting cascade
84
Function of the coagulation cascade
- Forms a fibrinous meshwork at an injured or inflamed site
85
Why is it important for the clotting cascade to form a fibrinous meshwork at an injured or inflamed site?
- Prevents the spread of infection (localizes microbes)
- Keeps microorganisms and foreign bodies at the site of greatest inflammatory cell activity
- Forms a clot that stops bleeding
- Provides a meshwork for repair and healing
86
What is the main substance involved in the clotting system?
Fibrin - an insoluble protein
87
* Place the clotting cascade in sequential order
```
1- WBC adherance
2- Kinin released
3- Platelet activation factor
4- Platelets
5- Fibrin
```
88
Does platelet activation factor appear in a clot? Why or why not?
No. Because they’ve all been used up at that point
89
Primary form of kinin:
Bradykinin
90
Function of the kinin system
- To activate and assist inflammatory cells
| Kinins activate and help inflammatory response
91
What does bradykinin do?
- Causes vascular permeability (dilation of blood vessels)
- Causes smooth muscle contraction
- Continues pain
92
What starts pain?
Prostaglandins
93
What continues pain?
Bradykinin
94
What are phagocytes?
Cellular component of inflammation that engulf and destroy microorganisms
95
What is a neutrophil?
A phagocyte that removes debris from area of injury
96
What is a “field of debris”?
The area around an injury
97
* When do neutrophils arrive to inflammatory site?
Within 6-12 hours of initial injury
| They arrive first
98
When are neutrophils most predominate?
During EARLY inflammatory responses
99
What does a neutrophil do?
Ingests bacteria, dead cells, and cellular debris
100
How long do neutrophils stay at the site of inflammation?
They are short lived and become a component of purulent exudate when they die
101
Which white blood cells are characteristic of chronic inflammation?
Monocytes & macrophages
102
Function of monocytes and macrophages
Provide LONG-TERM defense against infectious agents
103
Where are monocytes and macrophages produced?
Bone marrow
104
Specifically, when do macrophages arrive to inflammatory site?
- 24+ hours after neutrophils
| - about 3 to 7 days after initial injury
105
How long do macrophages stay at the site of inflammation?
Stay through out the rest of the inflammation process
106
Which white blood cells arrive early to the site of inflammation?
Neutrophils
107
Which blood cells arrive late to the site of inflammation?
Macrophages
108
When these show up, we know we’re near the end of the inflammatory process
Macrophages
109
Function of eosinophils
- Control vascular effects of serotonin and histamine (part of anaphylactic response)
- Regulation of vascular mediators
- Dissolve surface membranes of parasites
- Mildly phagocytic but has more of an affinity for BALANCE
110
Why do eosinophils balance serotonin and histamine?
To keep the inflammatory response down
111
What do platelets do?
Once activated, result in degranulation and interaction with components of the coagulation system
112
What do cytokines deal with?
- Immunity
| - Immune response
113
What do chemokines deal with?
- White blood cells
| - White blood cell break-up
114
Cellular products related to kinin:
Bradykinin
Cytokines
Chemokines
115
Most important function of interleukins:
General enhancement or suppression of inflammation (can suppress immune response with anti rejection medications)
116
What causes the local manifestations of inflammation to appear?
Results from vascular changes and corresponding leakage of circulating components into the tissue
117
What is the heat in inflammation caused by?
Vasodilation
118
What is the redness in inflammation caused by?
Vasodilation
119
What is swelling in inflammation caused by?
Exudate
120
What is the pain in inflammation caused by?
Exudate
121
What is exudate?
Extra products coming out around injury
| Ex: pus, drainage, etc.
122
What is loss of function a result of?
The result of the other clinical manifestations of inflammation (redness, heat, swelling, pain) combine and result in loss of function
123
What are the local manifestations of acute inflammation caused by?
Vascular changes and exudation
124
What is exudate made up of?
Dilute toxins produced by bacteria (toxins, bacterial waste products, bacterial digestion)
125
Function of exudate:
- Carries plasma proteins and leukocytes to the site and holds them there for a bit
- Carries away bacterial toxins, dead cells, debris, and other products of inflammation (left over from clean up)
126
What does serous exudate indicate?
| What does it look like?
- Indicates early inflammation
| - Water and clear with a reddish/pink tinge
127
Example of where serous exudate can be found
Blister
128
What type of exudate occurs early in the inflammation process?
Serous exudate
129
What does fibrinous exudate indicate?
| What does it look like?
- Indicates severe or more advanced (or prolonged) inflammation
- Looks like a clot - Thick and clotted
130
Example of fibrinous exudate
Lobar pneumonia
131
Which exudate occurs late in the inflammation process?
Fibrinous exudate
| Because fibrin comes in later
132
Another name for purulent exudate?
Suppurative exudate
133
What does purulent exudate indicate?
| What does it look like?
- Indicates a bacterial infection
| - White, may have green tinge
134
What is an example of purulent exudate?
Abscess (walled-off lesion)
135
What happens to form purulent exudate in particular?
- Large number of leukocytes accumulate
136
What does hemorrhagic exudate indicate?
| What does it look like?
- Indicates bleeding
| - Looks like blood running out (because it contains erythrocytes (blood)
137
What is fever caused by?
Exogenous and endogenous pyrogens
| These act directly on the hypothalamus
138
How are fevers risk/benefit?
They are beneficial - defense against microbes/infection
They are harmful - Increase host’s susceptibiliy to endotoxins
139
How can an active infection be detected by lab work?
If there are >11,000 WBCs per mL of blood
140
What is leukocytosis?
- Increased numbers of circulating leukocytes
141
What does a “shift to the left” mean?
Presence of circulating immature neutrophils
(because infection is so bad, so many new WBCs being made, all WBCs are immature. This slows down body’s ability to fight infection)
142
What are the systemic manifestations of inflammation? (What is increased?)
- Increased numbers of circulating leukocytes
- Increased circulating plasma proteins
- Increased plasma protein synthesis
143
Where are the plasma protiens realeased during inflamation?
- From the liver
144
What is a C-reactive protein test?
- An acute-phase reactant test that can determine whether there is prescence of chronic inflammation. Results will either be positive or negative
145
What do the results of a C-reactive protein test indicate?
- C-reactive protein is an acute-phase reactant, so:
- If there is presence of the protein, we are in the first 24-48 hours of onset of inflammation
- If it’s negative, there is chronic inflammation
146
When does C-reactive protein appear after onset of inflammation?
- Protein that appears 24 to 48 hours at onset of inflammation
147
What does ESR stand for?
Erythrocyte sedimentation rate
148
What is another name for ESR?
‘Sed rate’
149
What is sed rate used for?
Most commonly, to monitor malignant disease.
| Sometimes to monitor inflammation (but not used to identify where we are at in the inflammation process)
150
What characterizes chronic inflammation?
Lasting weeks or longer, regardless of cause
151
In general, what is chronic inflammation?
- Unsuccessful acute inflammatory response
- Without much acute response due to high lipid content microorganisms (microorganisms growing in patients with high lipid content)
- Persistant irritation from chemicals, particulate matter, or physical agents
152
Characteristics of chronic inflammation
| What does the body do in this situation?
- Dense infiltration of lymphocytes and macrophages
| - If macrophages cannot protect the host, the body walls off the site and forms a granuloma
153
What is an example of a granuloma formed from chronic inflammation?
Tuberculosis granuloma
154
What does resolution mean?
Returning injured tissue to the origional structure and function
155
What happens during tissue repair?
- Body repairs what tissue it can, then replaces destroyed tissue with scar tissue
156
What is scar tissue primarily composed of and why?
Collagen
| To restore the tensile strength of the tissue
157
What is the number one issue to address in an injury that has function-related issues?
Scar tissue because it usually causes loss of function
158
If patient has injury that has a lot of scar tissue, which has caused loss of function, what happens?
Surgical procedure called escarotomy
159
What is an escarotomy?
Surgical procedure that involves removal of scar tissue so less grows back and patient can restore some movement in area of injury
160
What is debridement?
- Surgical procedure where areas of the wound is cut away
| - Cleaning up the dissolved clots, microorganisms, erythrocytes, and dead tissue cells
161
What steps occur during healing of a wound?
- Filling in the wound
- Sealing the wound (epithelialization)
- Shrinking the wound (contraction)
162
What occurs during the reconstructive phase of wound repair?
- Development of granulation tissue (new growth of tissue)
- Fibroblasts synthesize and secrete collagen
- Contraction
163
Most important cell during the reconstructive phase of repair
Fibroblasts
164
What do fibroblasts do? During which phase do they do this?
Synthesize and secrete collagen during reconstructive phase of wound repair
165
When does contraction of a wound occur? When is it noticable?
- Takes place during the reconstructive phase of repair
| * - Noticable 6-12 days after injury
166
What is contraction of a wound?
Inward movement of wound edges
| Body does this on its own
167
What things are occurring during contraction of a wound?
- Collagen deposits
- Tissue regeneration
- Further wound contraction
168
What occurs during the maturation phase of wound repair?
- Collagen deposits
- Tissue regeneration
- Wound contraction continues
- Scar tissue is remodeled
- Capillaries disappear
169
Key resolution and repair product used in wound healing?
Collagen
170
Overall, what happens during the reconstruction phase of healing?
- Formation of granulation tissue
- Fibroblast proliferation
- Collagen synthesis
- Epithelialization
- Contraction
- Cellular differentation
171
Overall, what happens during the Maturation phase of healing?
- Continuation of cellular differentation
- Scar tissue formation
- Scar remodeling
172
Another name for primary intention?
Primary healing
173
Another name for secondary healing?
Secondary intention
174
What does primary healing mean?
A wound that has healed under conditions of minimal tissue loss
*This is a closed wound
175
What is an example of a primary wound?
Surgical incision with ends approximated
176
What does it mean if a wound’s ends are approximated?
The ends of the wounds are closed
177
What does secondary healing mean?
A wound that requires a great deal more tissue replacement
| *This is an open wound
178
Examples of a secondary wound
- Burns
- Large surface wounds
- Infection
- Decubitus (ulcer)/bed sore
179
Things that show dysfunction during inflammatory response:
- Hemorrhage
- Fibrous adhesion
- Infection
- Excess scar formation
- Wound sepsis
- Hypovalemia
- Hypoproteinemia
- Anti-inflammatory steroids
180
What causes hypovalemia?
- Vasodilation
- Permeability
- Loss of blood
181
What is hypoproteinemia?
Low protein (protein is required for good wound healing, so this would slow healing process)
182
Dysfunction that occurs during reconstructive phase of wound healing
- Impared collagen matrix assembly
- Impared epithelialization
- Impared contraction
183
Example of impared collagen matrix assembly
Keloid scar (overgrowth of collagen in a wound)
184
Word for skin reproduction
Epithelialization
185
What can cause impared epithelialization?
- Anti-inflammatory steroids
- Hypoxemia
- Nutritional deficiencies
186
What does impared contraction of a wound cause?
Contracture - if a body part is stuck in one position, it causes wound to not heal
187
What is hypoxemia?
Low blood oxygen
| *Blood oxygen under 94
188
What product does platelet-activating factor have similar effects to?
Leukotrienes
