Inflammation Flashcards
Inflammation
- first line of defense
- only occurs in vascularized tissue
Inflammation is the reaction of…
vascularized tissue injury
Inflammation is characterized by…
inflammatory mediators
- inflammatory cells drive process
Key Purposes of Inflammation
- get rid of pathogen creating problem
- make way for restoration or healing
- prevent tissue damage + infection
- prepare damaged tissue for repair
- prepare immune response
first line of immunity function and barriers
“innate” immunity: natural born
- prevents microorganism entry
barriers
- physical (skin)
- chemical (macrophages, stimulating chemical messengers) ; (cellular, molecular)
- mechanical
Innate immunity employs…
rapid cellular and chemical responses
What cells make up innate immunity?
- phagocytes
- neutrophils
- macrophages
- natural killer cells
- chemical mediators
Second line of immunity
“adaptive” or “acquired” immunity
interactions between immune and antigens
recognition between self (body cells) and non self
slower than innate, but more specific
Example of secondary (adaptive) immunity
viruses and vaccines
- previous exposure: immune system forms antibodies
Secondary line of immunity target
very specific target: 2 types
- Humoral (B-cells)
- Cell Mediated (T-cells)
“-itis”
- refers to inflammatory conditions
- not necessarily a disease
Acute Inflammation
- short inflammatory process
- lasts a few minutes –> several days
Acute Inflammation key feature - definition + components + cells
exudation
- movement of inflammatory + immune system cells into the extravascular tissues
- includes: fluid + plasma components and LEUKOCYTES
- when it occurs, dominated by NEUTROPHILS
Chronic Inflammation
- condition usually begin as acute and then develops to chronic
- lasts for days to years
- local or systemic
Chronic Inflammation - proliferation of…
- blood vessels
- tissue necrosis
- fibrosis
Chronic Inflammation is dominated by what cells?
- lymphocytes
- macrophages
Key Difference between Acute and Chronic Inflammation
acute has EXUDATION
chronic has FIBROSIS
Causes of chronic inflammation
- recurrent progressive acute inflammatory process
- viruses and bacteria that lay dormant
- talc or silica powder from plants
Nonspecific Chronic Inflammation
- Progression
- Localized or systemic?
- diffuse accumulation of macrophages and lymphocytes
ongoing chemotaxis –> infiltration of macrophages –> fibroblast proliferation –> scar formation
- scar formation: hard + avascular
- systemic
Granulomatous Inflammation
- small lesion (1-2mm)
foreign body giant cell
- foreign bodies (blister or suture) are surrounded by macrophages –> surrounded by lymphocytes
3 Phases of Inflammation
- vascular phase
- cellular phase
- Inflammatory mediators
Vascular Phase of inflammation is the process of…
…clotting, edema, and beginning of pain
Vascular Phase of inflammation contains changes in…
small blood vessels at the site of injury
The Vascular Phase of inflammation is initiated by…
the release of chemical mediators
Vascular Phase of inflammation is characterized by (4)…
- vasodilation, after temporary period of vasoconstriction
- changes in blood flow
- increased permeability in capillaries
- leakage of fluid into extravascular tissues (exudation)
In the vascular phase of inflammation, increased capillary permeability allows…
granulocytes to exit the vascular system and move to the injured tissue
changes in the vascular phase of acute inflammation prepare…
cellular response
Capillary vasoconstriction vs. vasodilation
vasoconstriction: limits blood loss
vasodilation: increases blood flow
Vascular phase of inflammation speed and impact
occurs quickly
major part of inflammation
Cellular phase sequence of events
- leukocytes go to site of injury to destroy offending agent and clear damaged cells (phagocytosis)
sequence
- margination and adhesion
- transmigration
- chemotaxis
- leukocyte activation + phagocytosis
What occurs during the Margination and Adhesion stage of the Cellular phase?
buildup of leukocytes on blood vessel wall (endothelium)
- leukocytes slow their migration, adhere tightly to endothelium, and begin to move along the periphery of blood vessels
What occurs during Transmigration Stage of the Cellular phase?
- inflammatory mediators secrete chemicals that cause endothelial cells to separate
- leukocytes move through the spaces in walls and unto tissue space
What occurs during the Chemotaxis stage of the Cellular phase?
- a dynamic + energy driven process
- inflammatory mediators direct the movement of leukocytes to site of infection
- once leukocytes exit capillaries, they are guided through the tissue by chemoattractants
What are chemoattractants?
bacterial + cellular debris
protein fragments
chemokines
What are chemokines a subgroup of and what are they secreted by?
- subgroup of cytokines
- secreted by immune and non-immune cells (macrophages)
Chemokines function
small proteins that direct trafficking of leukocytes during the early stages of inflammation
What are cytokines?
cell communication molecules
grouped w/ chemoattractants
What occurs during Leukocyte Activation and Phagocytosis stage of Cellular Phase?
- recognition, adherence, engulfment, intracellular killing
- cleans up dead cells
Phagocytosis is initiated by…
the recognition and binding of particles by specific receptors on the surface of phagocytic cells
What are Inflammatory mediators? What are the 2 types?
activated chemical substances that coordinate with the vascular + cellular phase to direct cells and process inflammation
- plasma derived
- cell derived
Plasma Derived inflammatory mediators are synthesized in…
the liver
Plasma Derived inflammatory mediators - components
components MUST BE ACTIVATED by enzymes
- acute phase proteins
- coagulation factors
- complement proteins
Plasma Derived components - Acute Phase Proteins (timeline + effects)
- short, quick reactions
- causes fever and chills
Plasma Derived components - Coagulation factors (purpose and products)
- proteins that aid in hemostasis + blood clotting
includes KININS
- activated kinin system produces bradykinin
- vasoactive: vasoconstriction and vasodilation (increases capillary pressure edema)
CLOTTING
- thrombin
- contributes to vascular phase
Plasma Derived components - Complement proteins (purpose + system)
- help antibodies respond like they should
complement system
- functions as enzymes as part of inflammatory response
- interacts w/ multiple molecules + proteins within the body
- help direct leukocyte to site of injury/infection
Cell Derived inflammatory mediators are derived from…
intracellular granules (pockets)
Cell Derived inflammatory mediators function
to respond to injury or trauma
some mediators need to be secreted (inactive)
some mediators need to be newly synthesized (ready for action once formed)
Cell derived mediator types:
- histamine
- arachidonic acid metabolites
- cytokines + chemokines
- nitric oxide + free radicals
Cell derived mediators - histamine
- one of the 1st to be released
- a vasodilator
- produces swelling, itching
- ## works with serotonin
Cell derived mediators - arachidonic acid metabolites (2 stimulation pathways)
- lipoxygenase pathway
- cyclooxygenase
Cell derived mediators - arachidonic acid metabolites effects:
- stimulates smooth muscle contraction
- increases capillary permeability
- causes vasodilation
- causes bronchoconstriction
- promotes platelet function
Cell derived mediators - cytokines + chemokines (purpose and effects)
- generate systemic responses during inflammation
- decrease BP
- increase HR
- fever, chills
Cell derived mediators - nitric oxide + free radicals (effects)
- vasodilation
- smooth muscle relaxation
- antagonism of platelet adhesion
- leukocyte recruiter
Cells of inflammation
- platelets
- neutrophils
- eosinophils
- monocytes
- basophils
- mast cells
Cells of inflammation - platelets function and effects
- involved in hemostasis, which maintains blood flow
- causes clots
Cells of inflammation - neutrophils
early birds - arrive early at site of inflammation
- essential part of acute inflammation
Cells of inflammation - eosinophils
- increase during allergic reactions (anaphylaxis) or parasitic reactions
- involved in hypersensitivity reactions
Cells of inflammation - monocytes (what they produce + what they are heavily involved in)
- produce potent inflammatory mediators
- heavily involved w/ growth doctors for healing tissues
Cells of inflammation - basophils (derived from…)
bone marrow
Cells of inflammation - mast cells
- activation results in release of granular mediators: degranulate
- developed later
- release multiple chemicals, such as histamine
Tissue injury needed for mast cells to…
degranulate and release histamine and chemotaxic chemicals (neutrophils and eosinophils)
LOCAL manifestations of inflammation
- vascular changes (vasodilation/constriction)
- leukocyte infiltration (build up of vessel wall)
- severity of reaction (length of time)
- specific cause (infection)
- site of involvement
SYSTEMIC manifestations of inflammation
acute phase response begins within hours or days
leukocytosis - increased white blood cells
lymphadenitis - reaction in the lymph nodes; swelling from increase of fluid
Terms for signs of inflammation: rubor
redness
Terms for signs of inflammation: tumor
swelling
Terms for signs of inflammation: calor
heat
Terms for signs of inflammation: dolor
pain
Terms for signs of inflammation: functio laeso
loss of function
Exudates: serous
something clear outside of blood
ex: fluid in blisters
Exudates: hemorrhagic
severe trauma -→ blood
Exudates: fibrinous
- thick, stick fluid
- usually in scars -→ likely in chronic inflammation
Exudates: membranous
thick mucous
Exudates: purulent or suppurative
- some type of abscess
- can happen as a result of an ulceration
Goal of acute inflammation
complete restoration of normal tissue
What is acute inflammation restoration dependent on?
- minimal cell death/damage
- tissue capacity for regeneration
- overall health and nutrition
- removal of causal agent
- removal of debris and fluid
