L19- Immune Flashcards
Immune system
Includes cells, processes & chemicals that keep us disease free
What causes disease?
- Pathogens: bacteria, viruses, parasites
- Cancer cells
Immunity
Ability to recognize and eliminate foreign invaders or abnormal “self” cells that cause disease ( cancer cells)
Immunology
Study of immune processes
Big picture function of immune system
Keep invaders out!
- external body surface- cutaneous membrane
- internal body surface - mucous membranes
If invaders get in what does the immune system do
- eat them = cells phagocytize
- shoot them = cells secrete/ inject chemicals into them
What are the 2 divisions of the immune system?
Nonspecific and specific
Nonspecific immune system
Born with it (innate)
- involves: WBCs ( not lymphocytes), chemicals, processes that attack any bacteria, viruses, cancer cells, virally infected cells
Specific immune system
- built through exposure to pathogens (acquired)
Involves: B & T lymphocytes
- clones B &T lymphocytes
- have ability to recognize all foreign antigens
Antigens
Molecules on a cell that triggers immune cells in a host
Antigens include…
- Molecules on the surface of a bacteria, virus, virally infected cell, cancer cells
- toxins secreted by bacteria
- Molecules on cells of tissue grafts from a donor
Autoimmunity
Attack on “self” cells
Allergy
Reaction to nonpathogenic substances
Immune deficiency
Immune system not functioning well
What are the primary lymphatic organs
Thymus & red bone marrow
Primary lymphatic organs are the site of ____________ & ______________ of WBCs
Production, maturation
Maturation
B & T lymphocytes learn to distinguish “self” from “non self” antigens
T lymphocyte maturation occurs
In the thymus
B lymphocyte maturation occurs
In the red bone marrow
Production of WBCs (lymphocytes, eosinophils, neutrophils, basophils and monocytes) happens
In red bone marrow
Secondary lymphatic organs include
Lymph nodes and the spleen
Lymph nodes function
Immune surveillance of lymph
Spleen function
Immune surveillance of blood
Lymphatic tissues include
Tonsils, appendix & MALT ( mucosa associated lymphoid tissue)
Where is lymphatic tissue found?
Anywhere the body opens to the outside world
The secondary organs and lymphatic tissue are the site of ________
Action of B&T lymphocytes
Nonspecific immune system external barriers
- cutaneous membrane (skin)
- mucous membranes
- chemicals in saliva/ tears
- acid in stomach (HCl)
- flora = healthy microbes
Nonspecific immune system internal barriers
- chemicals = lysozyme, interferon, complement
- nonspecific cells = phagocytes, NK cells
Inflammation process
4 signs of inflammation
Redness, heat, swelling & pain
Inflammation process
Damage ➡️ chemical change in interstitial fluid
- stimulating mast cells to release histamine
- histamine ➡️ vasodilation ( increase in blood flow) ➡️ phagocytes, complement, nutrients to repair damage
What cause heat, redness, swelling and pain in inflammation
Histamine = causes swelling
Vasodilation due to histamine being released = causes redness
- vasodilation cause increase blood flow = which causes heat to be present
- pain = swelling and chemicals present
