physiology of white blood cells Flashcards
what are the main 2 types of lymphocytes?
B cells or T cells
what do both B cells and T cells have?
antigen specific receptors
what percentage of lymphocytes are natural killer cells?
5%
what are the key features of basophils?
- lobed nuclei and heavily granulated cytoplasm
- non-phagocytic cells
how do basophils function?
by releasing pharmacologically active substances from the cytoplasmic granules
what is the biology of basophils?
- circulate the blood
- recruited to the sites of allergic reactions or ectoparasite infection
- express FcRI
- allergen can bind to allergen-specific IgE bound to the cell surface of basophils causing degranulation of effector mediators
what are the key features of eosinophils?
- have bilobed nuclei and granulated cytoplasm
- motile phagocytic cells that can migrate from the blood into the tissues
what is the biology of eosinophils?
- majority are located in tissues
- recruited to sites of allergic reactions
- express FcRI upon activation
- granules containing toxins
- attack parasites in GI, respiratory and genito-urinary tracts
what are features of neutrophils?
- polymorphonuclear cells
- multilobed nucleus
- found in the blood
- rapidly recruited to sites of infection/injury
- short lifespan
- myeloperoxidase
what are the first responders to infection?
neutrophils
what are features of monocytes?
- kidneys shaped nucleus
- reservoir of monocytes in the spleen
- also circulate in the bloodstream where they enlarge
- migrate into tissue approximately 1 day after release from the bone marrow
- blood-borne phagocytes
what are the precursors to macrophages?
monocytes
what are the features of macrophages?
- found in tissues
- 5-10 fold larger than monocytes
- contain many more organelles compared to monocytes
- lifespan is months to years
- tissue-resident phagocytes
what are the key features of bacterial infection?
increased neutrophils (increased monocytes in chronic infection)
what are the key features of viral infection?
increased lymphocytes and sometimes increased monocytes
what are the key features of parasite infection?
increased eosinophils and activation of mast cells
what are the key features of fungal infection
increased monocytes