Lecture 5-7 Flashcards
What is innate immunity?
The relatively non-specific ability to phagocytize foreign organisms, particles, some cancerous cells and exhausted/worn out cells such as old RBC’s
What is adaptive immunity?
A specific response is generated principally by the production of antibodies and so-called “memory” cells which “remember” the antigen and are therefore able to mount a far quicker and more effective response with subsequent exposure.
Name the 3 granulocytes.
Neutrophils, Eosinophils, Basophils
Name the 2 agranulocytes.
Lymphocytes, Monocytes
What is the function of neutrophils?
Destroy bacteria by phagocytosis
D: 6-9 days
LS: 6 hrs to a few days
3000-7000 per mm^3
What is the function of Eosinophils?
Turn off allergic responses and kill parasites
D: 6-9 days
LS: 8-12 days
100-400 per mm^3
What is the function of basophils?
Release histamine and other mediators of inflammation
D: 3-7 days
LS: ? few hrs to few days
20-50 per mm^3
What is the function of lymphocytes?
Mount immune response by direct cell attack (t-cells) or via antibodies (B-cells)
D: days to weeks
LS: hrs to years
1500-3000 per mm^3
What is the function of monocytes?
Phagocytosis: develop into macrophages in tissues
D: 2-3 days
LS: Months
______ and _____ cells release histamine and other chemicals involved in inflammation.
Basophils; Mast
How does leukocytes move around the body?
Via the blood and lymph
Granulocytes and monocytes seeks out invading organisms by means of ___________
chemotaxis
Which leukocytes has the most abundance in the blood?
Never: Neutrophils (62%) Let : Lymphocytes (30%) Monkeys: Monocytes (5.3%) Eat: Eosinophils (2.3%) Bananas: Basophils (0.4%)
T or F? Granulocytes has intracellular granules and have multilobed nuclei.
True
What are natural killer (NK) cells?
A class of lymphocytes that bind to cells bearing foreign antigens without specific recognition and kill them directly; major targets are virus-infected cells and cancer cells; participate in antibody-dependent cellular cytotoxicity (ADCC)
T or F? Granulocytes and lymphocytes protect primarily by phagocytosis, (innate)
False, Granulocytes and granule-free monocytes not lymphocytes.
What type of stem cells are WBC’s derived from?
pluripotent hematopoietic stem cells (from there, they could become myeloblasts or lymphoblasts)
___ ______ _____, typically released with by macrophages at the site of infection, trigger the production of the appropriate WBC’s in the bone marrow.
Colony-stimulating factor
T or F? The majority of WBC’s are circulating within the blood.
False, ~6 days worth of WBC’s are stored in bone marrow or lymphoid tissue.
What is the typical lifespan of granulocytes?
`4-8hrs in the blood plus ~5-6 days in the tissues where needed (could be reduced when fighting infections)
T or F? Monocytes spend about ~10-20hrs in the blood before entering tissues where they enlarge and mature into active tissue macrophages which can survive for months.
True
Lymphocytes enters the blood via the ________.
Lymph, where they circulate only to invade tissues and subsequently re-enter the lymph
Immune cells can pass through “gaps” in the capillary endothelium to enter the tissues by a process called _______.
Diapedesis
What are released by damaged cells at the site of infection to attract appropriate immune cells?
Chemokines
_____ are primarily found in the blood while ___ move into the tissues. (However, when tissue damage and inflammation occur many substances are released which attract these cells by chemotaxis)
Neutrophils ; macrophages
What are the 2 innate mechanisms that attracts phagocytes to pathogens?
- Many pathogens have roughened surfaces, our cells are smooth.
- Most pathogens lack the repellant protective coats that our cells possess.
What is the so called alternate complement pathway?
A complement system that can be activated without the involvement of antibodies during inflammation.
Complement system factor ____ binds to cell surface/cell wall carbohydrates of bacteria which allows more effective phagocytosis. (opsonization)
C3b
Which phagocytes projects pseudopodia around a pathogen to engulf it to be phagocytized?
Neutrophils and macrophages
T or F? Neutrophils can ingest worn out RBC’s and even malaria parasites.
False, macrophages not neutrophils
Macrophages releases ______ (neutrophils does not release this) which can attack the thickened membranes which some bacteria possess.
lipases
What is the membrane attack complex?
A group of complement proteins that form channels in the surface of microbe, making it leaky and killing it.