Lecture 12 Flashcards
What are the 3 lines of defense in the local support and defense system
1) Non specific physical and chemical surface
2) Non-specific inter-cellular and chemical defense
3) Immune response
What is the innate immute system
Natural, not learned through experience
What does the innate immune system consist of
1) Non specific physical and chemical surface
2) Non-specific inter-cellular and chemical defense
What is the adaptive immune system
Specific defense, learned through experience
What is part of the adaptive immune system
Immune response
What does the first line of defense consist of (7)
Tears, skin, large intestine, saliva, respiratory tract, stomach, bladder
How do the tears, skin and LI protect the body
Tears
– Wash away irritating substances and microbes
Skin
– Provides physical barrier to entrance of microbes
– Acidic pH discourages growth of organisms
– Sweat and oil secretions kill bacteria
Large Intestine
– Normal bacterial inhabitants keep invaders in check
How does the saliva, respiratory tract, stomach, and bladder protect the body
Saliva
– Washes microbes from teeth and mucus membrane of mouth
Respiratory tract
– Mucus traps organisms
– Cilia sweeps away trapped organisms
Stomach
– Acid kills organisms
Bladder
– Bladder washes microbes from urethra
What are the 4 types of defense in the second line of defense
1) Defensive cells
2) Defensive proteins
3) Inflammation
4) Fever
What are the 3 types of defensive cells and their roles
Phagocytic cells: engulf invading organisms
Eosinophils: kill parasites
Natural killer cells: kill invading organisms and cancer cells
What are the 2 types of defensive proteins and their roles
Interphons: slow spread of virus in body
Complement system: stimulates histamine release; protoes phagocytosis, kills bacteria, enhances inflammation
What is inflammation
Widening of blood vessels and increased capillary permeability, leading to redness, heat, swelling and pain: brings in defense cells and speeds healing
What is a fever
Abnormally high body temp: slows bacterial growth, speeds up body’s defense
What is phagocytosis
Phagocytosis: cellular process for ingesting and eliminating particles larger than 0.5 μm in diameter
What are phgagocytes
Phagocytes: white blood cell that uses phagocytosis to engulf bacteria, foreign bacteria, and dying cells
Explain the 2 types of phagocytes
Neutrophils: first on scene, consume bacteria
Macrophages: consume almost anything
What are non-phagocytes
Non-phagocytes: target pathogens/invading cells too large for phagocytosis
Explain the 2 types of non-phagocytes
Eosinophils: discharge enzymes that digest target
Natural killer cells: constantly circulate and “patrol” for non-self. Target cancer cells. Release perforin and proteases to destroy cells
Where are defensive protiens synthesized
Mainly in the liver
Are defensive protiens released in active or inactive form
Inactive
What are defensive protiens activated by
Polysaccharides on bacteria surface
Antigen/antibody complexes (adaptive immune response)
What are defensive protiens deactivated by
Normally deactivated by native proteins in the blood and the surface of the body’s own cells
What do defensive proteins do
Enhances ability of antibodies and phagocytic cells to clear microbes and damaged cells from body, promotes inflammation and attacks the pathogen’s cell membrane
What is inflammation (biologically)
- Blood vessels widen
- Capillaries become permeable
What is the treatment for inflammation
Treatment RICE: rest, ice, compression, elevation
What causes inflammation
Occurs in response to tissue damage and stress such as:
– Bruises and torn tissue (acute inflammation)
– Disease states, such as arthritis and obesity (chronic inflammation)
Are fevers always caused by infection
No, infections can cause fevers but do not always
What causes fevers
Caused by heat preservation and increased production due to fighting infection or others
What are fevers not due to infection called
Fever not due to infection = fever of unknown origin
What can cause a fever of unknown origin
Caused by endocrine disorder, cancer, drug reactions, ect
What are parenchymal cells
Critical “functional” portion of tissue (gland, organ)
Most prominent cell in terms of mass
Give 3 examples of parenchymal cells
Liver - hepatocyte
Skeletal muscle - myocyte
Heart - cardiomyocyte
Brain - neurons
Adipose tissue - adipocytes
Pancreas - various secretory cells
What are stromal cells
AKA non-parenchymal cells
Support parenchymal cells in forming LSDS
Like a framework
Give 3 examples of stromal cells
Neurons: control function of virtually all cells/tissue
Astrocytes: support neural functions
Capillary endothelial cells - control blood flow, provide neutries, oxygen
Cells of lymphoid organ - resident T-cells/B-cells, NK cells
Cells of myeloid (bone) origin - neutrophils, macrophages
Fibroblasts - make extracellular matrix and collagen
Stem cells - divide and replace parenchymal cells
Gap junctions - communication between parenchymal cells (ex. Intercalated discs between cardiac cells)
What are 3 other tasks of the LSDS
1) Local tissue damage by process that are not due to infectious pathogens
2) Normal tissue turnover
3) Looks out for appearance of transformed cell populations (cancer)
What is involved in Normal tissue turnover
Cell death
Tissue repair, regeneration during wound healing
