Week 5 - The Innate Immune System and Disorders Flashcards
(42 cards)
What is the immune system
System in the body responsible for maintaining homeostasis by distinguishing self from non self (foreign) and producing an appropriate response
Where do immune cells develop from
primary organs
Where do immune cells respond
secondary organs
What are primary organs
main organs in a system that is essential for performing key functions
What are the primary organs for the immune system
- Thymus
- Bone Marrow
What is the thymus
glandular organ near the hear - where T cells learn their jobs (T for thymus)
What is bone marrow
Blood producing tissue located inside certain bones (flat bones e.g. pelvis)
Multipotent stem cells give rise to all of the different types of blood cells
What are secondary organs
organs that support or assist the primary organs in carrying out their main functions
What are the secondary organs for the immune system
- spleen
- lymph nodes
- lymphoid tissue
- lymphatic vessels
What is the spleen
- serves as a filter for the blood
- removes old and damaged red blood cells
- removes infectious agents and uses them to activate lymphocytes
What impact would a splenectomy have on immune response
splenectomy = removal of the spleen
Increased susceptibility to infection because you can’t filter the blood anymore
What are lymph nodes
- small organs containing lymphoid tissue found all over the body )neck, armpits)
- filters lymph (clear fluid that carries waste and immune cells) before returning filtered lymph into the bloodstream
- filter extracellular fluid to remove dead cells, antigens and other stuff to present to lymphocytes
What is lymphoid tissue
- Connective tissue with white blood cells enmeshed in it (special tissue full of immune cells - which makes and stores immune cells)
- adenoids, tonsils, appendix, Peyer’s patches
- Found in areas where there is potential for microorganisms to enter the body
What are lymphatic vessels
a network of thin walled tubes that transport lymph throughout the body
they collect fluid (lymph) that has “leaked” out from the blood into the tissues and returns it to circulation via lymph nodes
What are the 2 defense systems we have
- innate system
- adaptive system
What is the innate immune system
the body’s first line of defense against infections. It’s fast acting, non specific and always ready to respond to pathogens
- present at birth
- non specific - just recognizes general danger signal
- occurs early
- responds quickly
- no memory
What is the adaptive immune system
Part of your immune system that leans to recognize and specifically target pathogens. Unlike the innate immune system, it’s slower to respond at first, but it’s highly specific and remembers previous invaders for faster responses in the future
- Specific
- Acquired
- Slower to respond
- Has memory
Which cells are involved in the innate immune system (5)
- Neutrophil
- Basophil
- Eosinophil
- Mast cell
- Natural killer cell
What are the 2 components of the innate immune system
- physical barrier
- cellular defense
What is involved in the innate immunity surface barriers
- Saliva - antibacterial enzymes
- tears - antibacterial enzymes
- skin - prevents entry **
- mucous - linings traps dirt and microbes **
- stomach acid - low pH kills harmful microbes
- good gut bacteria - out compete bad bacteria
Where are the innate immune defense cells found
body’s fluids and tissues
How is the innate immune system initiated
MAMP (or PAMP) binds to PRR and trigger intracellular signaling pathways leading to transcription of immune response genes
What are cytokines
A broad category of signaling proteins released by immune cells (like T cells, macrophages).
e.g.
- IL-1, IL-2
What are chemokines
A type of cytokine that specifically guide cell movement (chemotaxis). They attract immune cells to sites of infection, injury or inflammation.
