5. immune system Flashcards
What is inflammation and the 5 stages?
= a protective tissue response to injury or destruction of tissues
- process of inflammation serves to destroy, dilute or wall off both the injurious agent and injured tissues
5 stages: swelling, heat, redness, pain and loss of function
Cell types and their functions in Acute inflammation response
- Phagocytic cells = Engulf and destroy microorganisms
o Neutrophils : predominant phagocytic cell in early inflammatory response
o Macrophages: late in the inflammatory response, highly phagocytic and promotes wound healing - Monocytes: promotes tissue healing and contribute to tissue destruction during infection
- Eosinophils: release products that control the inflammatory response and are the principal cell that kills parasitic organisms
- Platelets: interact with proteins of the clotting system to stop bleeding and release a number of mediators that promote and control inflammation
Cell types and their functions in Chronic inflammation response
= inflammation that lasts more than 2 weeks
o Lymphocytes – process antigens coordinated a inflammatory response - B lymphocytes and T lymphocytes o Macrophages – specialised cells involved in detection, phagocytosis and destruction of bacteria - Also, present antigens to T cells and initiate inflammation by releasing cytokines that activate other cells o Plasma cells – important mediators of antibody production and delayed hypersensitivity responses
Adaptive (specific immune response) - role in preventing invasion of pathogens
= protects against pathogens and abnormal body cells (cancer)
- slow response
= involves activation of specific lymphocytes that combat a particular pathogen or other foreign substance
- inteensifies thee inflammatory response
- activates complement
- specific lymphocytes that combat a particular pathogen
- create memory
What are the two divisions of adaptive immunity
- humoral (antibody mediated immunity) - attack extracellular pathogens
- cellular (cell mediated) immunity: attack intracellular pathogens
Key WBC involved in adaptive immune system
B lymphocytes - become plasma cells which produce antibodies to bind to the target cell
T lymphocytes - for cell mediated immunity
T helper - control humpral immune response of B cells (essential for B cells and cytotoxic T cells activation)
T cytotoxic - effector cells which release chemicals that kills cells
T supressor cells - damp down immune response
Memory T cells - remain in lymph nodes ready to respond quickly to a second infection with the same antigens
What is Lymphocytic leukemia?
Blood cancer
- affects bone marrow and blood
- produces too many abnormal WBC
- typically slow growing cancer
What is Lymohoma
= blood cancer
- affects the lymph nodes
- starts in the immune system and affects the lymph nodes and lymphocytes (type of WBC)
Two main types
- Hodgkin’s - involves a specific type of abnormal B cell called a reed-sternberg cell
- non-hodgkins - which can start in either B cells or T cells
What is meningococcal meningitis?
Meningitis occurs as a result of the bacteria entering the blood stream and infecting the meninges = results in inflammation which can increase ICP leading to seizures, coma and death.
What is meningococcal septicaemia?
- Occurs when the bacteria enter the blood stream, dividing rapidly leading to a systemic inflammatory reaction
- The bacteria release toxins that cause blood poisoning
What is Disseminated intravascular coagulation (DIC)
Disseminated intravascular coagulation (DIC) = is a condition in which blood clots form throughout the body, blocking small blood vessels
Pathophysiological processes that may lead to disseminated intravascular coagulation?
- DIC begins with the formation of blood clots through the body bleeding once all the clotting factors have been consumed
- Provoked by several underlying factors:
o Sepsis, cancer, trauma and pregnancy complicated with eclampsia and other calamities - Results in thrombotic complications due to the intravascular formation of fibrin and diffuse haemorrhages, due to the consumption of platelets and coagulation factors
Define shock
= state in which the supply of blood to the tissue is inadequate to meet the metabolic demand of the body
List the 5 types of shock
- cardiogenic shock
- hypovolemic shock
- anaphylactic shock
- septic shock
- neurogenic shock
What is cardiogenic shock?
cardiogenic shock = due to heart problems
- occurs when heart cannot pump enough oxygen to brain, kidneys and vital organs
- most common cause is a heart attack
- impaired forward pumping of the heart: heart failure
= pump failure leading to hypoxia as the heart cannot pump blood around the body
- insufficient perfusion of tissues
- may be due to damaged heart and cardiac valve problems
