Chapter Six - Innate Immunity : Inflammation And Wound Healing Flashcards
Innate immunity: first line of defence
-physical, mechanical, biochemical barriers
Innate immunity : second line of defence
Inflammation, macrophage, neutrophils
Adaptive immunity
Third line of defence
-acquired or specific immunity
-B cell or T cell
Mast cells release
Histamine
Histamines =
Vasodilation
___ enter to stop blood loss
Platelets
______ arrive to phagocytize pathogen
Macrophages and neutrophils
When macrophages arrive to phagocytize, what accumulates
Pus
-dead phagocytes and pathogens
Rapid leakage and influx of
Leakage - ions
Influx - fluids
Since water follows sodium
During inflammation vascular ____ is a principle coordinator
Epithelium
Tissue close to vessel contains two involved cells
-mast cells
-dendritic cells
Mast cells
Important inflammation activator
-release histamine
Dendritic cells
Connect innate and adaptive immune response
Both innate and adaptive systems are recruited by
Chemical molecules
Chemical molecules are released from
Damaged or destroyed cells
Cytokines
General term for chemical molecules released
-they regulate innate and adaptive immunity
Cytokines can be
Pro inflammatory or anti inflammatory
Lymphokines
Cytokines released from lymphocytes
Monokines
Cytokines released from monocytes
-which change into macrophages
Macrophages and lymphocytes also released
Itnerleukin cytokines
Main interleukins are
IL-1 and IL-6
-self limiting compared to cytokines
IL-1
Produced by macrophages
IL-6
Produced by macrophages, lymphocytes and fibroblasts
COVID 19 activates a
Cytokine storm syndrome
-severe systemic inflammatory response
IL-6 has cytokine released =
Excessive recruitment of lymphocytes
COVID 19 treatment
Is production of IL-6 antibodies to counteract effect
TNF-a
A cytokine but not classified as an interleukin
-released by macrophages and mast cells
-induces multitude of pro inflammatory effects
Pro inflammatory effects
-fever
-cachexia
-fatal shock
-granuloma formation
Cachexia
Muscle wasting
Fatal shock is caused by
Gram negative bacterial infections
Antiflammatory cytokines are
Interleukin 10 lymphokine
Granuloma formation
Goal of inflammatory responses
-limit and control injury (limit blood and infection)
-intervention (clean wound, remove debris, antibiotics)
ITIS tells us
Where inflammation is located
Cell injury or death activates
Inflammation
cell death can be due to
-infection
-mechanical damage
-ischemia
-temp extremes
-radiation
Erythrocyte sedimentation rate or ESR
Determination of rate of RBC settling in saline solution
An increase in infection =
RBC bind to each other, becoming heavier and settle at a faster rate
Increased ESR =
Increased infection
C reactive protein is caused by
Effect on liver
C reactive protein increases in
Response to inflammation
An increase in neutrophils during blood work would signal that
The WBC have not got a hold of the infection yet
-actively fighting
Acute inflammation
-lasts less than two weeks
-swelling, pain, heat, redness
-localized and quick to diagnose
Three primary systemic changes in an acute inflammation
- Fever
- Leukocytosis or inc levels of circulating leukocytes
- Increased circulating proteins
Acute inflammation if response is unsuccessful can become
Chronic
Chronic inflammation
-longer Thant so weeks/months/years
-can be preceded by unsuccessful acute or distinct process without previous acute inflammation
Chronic inflammation causes microorganisms to
-be insensitive to phagocytosis
-they can survive macrophages
-produce toxins
Chronic inflammation presents as a
Dense infiltration of lymphocytes and macrophages
If macrophages are unable to stop tissue damage
Body walls off infected area by forming a granuloma
TNF -a drives ___ formation
Granuloma
-a cluster of WBC and other tissues
Simple explanation of a chronic inflammation
When the immune system is unable to protect body
-formation of granuloma -> walled off infection area
Transition from acute inflammatory to healing begins when
Immediately
Platelets
Clot formation
-initiate formation of unmanaged cells
Neutrophils
Clea wound of debris and bacteria
-last small amount of time
Macrophages
Release growth factors
-recruit fibroblasts
-promote angiogenesis
Angiogenesis
Development of new blood vessels
Proliferation and new tissue formation lasts
Three days to two weeks
Fibroblast proliferation =
Collagen synthesis
Epithelization
Epithelial cells migrate to wound
Remodeling and maturation phase lasts
Weeks to years
Remodeling and maturation phase: cellular differentiation continues
Unspeilized cells mature
-become specialize and perform important cellular functions
-scar tissue formation and remodeling
Fibroblast
Major remodeling cell
Primary intention
-clean incision
-early suture and is best choice for fresh wound with sufficient vascularization
Secondary intention
Gaping would = granulation
-much more extensive and edges can’t be brought together
What type of wound is “-ideal for contaminated or infected wounds a wound if left open to heal spontaneously”
Secondary intention
What wound results in a fine scar?
Primary intention
Tertiary intention
Delayed primary closure
-open wound by not gaping
-inc granulation
-allowed observation of wound
What intention is sutured closed and results in a wide scar
Tertiary intention
Adhesions
Abnormal union of membranous surfaces (common in bowel surgery)
-painful if it stops normal movements
Strictures and contractures
Excess of wound contraction
-healing cells tend to pull other cells towards them, causing contracture of tissue
Infections
Wound is reinfected with initial or new pathogen
Dehiscence
Incision separates following surgery and wound is considered dehisced
Evisceration
Surgical complication
-incision opens and abdominal organs protrude
Excess scar formation
Caused by excess tension and movement
Low blood supply =
Iscehmia, vasoconstriction and inhibits recovery process
High blood supply =
Increased blood clots
Obesity predisposed to
Infections
Excessive fibrin
Doesn’t get reabsorbed and cases fibrous adhesions
Diabetes
Potential for smaller vessel disease and prolonged wound healing
-hyperglycaemia
Hyperglycaemia
Excess glucose in blood
Hyperglycaemia =
Suppression of macrophages
Wound infection is
Infiltration of pathogen
Nutrition must meet
Metabolic needs of healing
Antineoplastic
Drugs used for cancer treatment to slow cell division
-has various side effects
-blocks formation of neoplasms
Neoplasms
New abnormal tissue growth
Steroids
Prevent macrophages from migrating to site