Non-specific Defence - Concepts Flashcards
The multiple dimensions the pathology uses to study disease
The cause of disease, how disease develops, and changes to the body resulting from disease and the consequences of these changes.
What often differentiates pathogens from normal flora?
The capacity to traverse natural barriers of the body.
What are the three major strategies a host has to combat potential pathogens?
Avoidance, resistance, tolerance.
For a pathogen to cause disease it must first…
Enter into the body of a host.
Substances produced by our bodies that act as physical or chemical barriers…
Lysozyme in tears. Our skin is slightly acidic. Ear wax and mucus is sticky. Nose hairs, ear hairs, eyelashes, eyebrows. Labia and foreskin.
The skin and mucous membranes represent what line of defense?
The first line of nonspecific defence mechanisms in the body.
What represents the second line of defense?
Phagocytic white blood cells, antimicrobial proteins, and the inflammatory response.
The five main types of white blood cells
Neutrophils, lymphocytes, monocytes, Eosinophils, and basophils.
The main white blood cells that are involved in nonspecific phagocytosis
Neutrophils and monocytes
Granulocytes
Neutrophils, eosinophils, and basophils. Cells with granules.
Mature monocytes are called what?
Macrophages.
What is the primary cause of lymph node swelling in response to disease?
The multiplication and swelling of monocytes.
Why is phagocytosis not always successful?
Some pathogens have a capacity to withstand digestion, and may replicate inside white blood cell. Some pathogens can escape from the vesicle and use the cells resources and take over cellular machinery. Some can produce toxins that kill the phagocyte.
What are the most important of the nonspecific defence proteins of the body?
The complement proteins and interferons.
The complement system
A group of soluble proteins produced in the liver, that function sequentially to trigger the distraction of micro organisms. Works both with the specific immune system and the innate immune system
When complement acts nonspecifically, what is the cascade usually stimulated by?
Polysaccharide components of bacterial or fungal cell walls.
What three main pathways of innate response are triggered by complement?
Membrane attack, inflammation, and phagocytosis.
What three events are caused by the initiation of the complement response?
Cytolysis, inflammation, opsonization.
How do interferons work?
They bind to the surface of uninfected cells and stimulate them to produce specialized enzymes which interfere with viral replication.
Are the effects of interferons short term or long term?
Short term.
What will trigger the inflammatory response?
Injury to cells or tissues (either physical or pathogenic), proteins/chemicals, enzymes, complement system.
How does dilation of blood vessel’s in response to signal molecules impact white blood cells?
It increases and slows blood flow around the site of injury, making it easier for white blood cells to move in and out and increases the amount of blood flowing through that tissue.
What is the immune system response?
Injured tissue releases signal molecules, there is an increased movement of immune system cells and molecules to the affected area, and then there is disinfection and cleaning of the area.
How much fluid is lost from blood vessels that the lymphatic system collects?
3-4 L/day
