leukocytes Flashcards
what are mobile units that work to prevent disease and infection?
leukocytes
which cells destroy invading agents by phagocytosis or by releasing inflammatory substances that help destroy the offending organism
myelocytes
which cells make up myelocytes?
granulocytes and monocytes
which cells function in connection with the immune system, form antibodies, which also destroy the invader?
lymphocytes
normal WBC count?
4,000-10,000 cells/mm^3
which type of leukocytes have multiple nuclei per cell, have granules under a microscope, and are known as granulocytes?
neutrophils, eosinophils, and basophils
where are myelocytes found/formed?
bone marrow
these are known as immature macrophages which turn into tissue macrophages
monocytes
these cells act on active infections by phagocytosis
neutrophils
these cells have weak phagocytosis, and work against fungal diseases such as asthma and inflammation
eosinophils
these cells are elevated in patients with allergies which are similar to mast cells
basophils
formed and stored in bone marrow until they are needed then released into the blood
ingest invading organisms by phagocytosis and antimicrobial action
granulocytes and monocytes
function as part of acquired immunity
“formed” and stored in lymph tissue (thymus, tonsils, lymph nodes, spleen, peyer’s patches)
lymphocytes and plasma cells
chemical released from inflamed tissue or foreign invader cause neutrophils and macrophages to move toward source of chemicals
chemotaxis
the way motion in which neutrophils and macrophages move through tissue by the extension of pseudopods
ameboid motion
the motion/process in which WBCs are squeezed through very small capillary pores towards the chemotactic source
diapedesis
WBCs recognize foreign material that has been tagged by an antibody and the C3b product of the complement cascade
opsonization
the complement cascade and antibodies will tag the foreign organism in order for our immune system to respond
what do neutrophils release to destroy the pathogen once it is inside the cell
proteolytic enzymes from lysosomes in the phagocytic vesicle
monocytes and macrophages are immature
monocytes have limited ability to fight infections until they enter ___?
the tissues
once monocytes enter the target tissues they become ____
tissue macrophages and fill with lysosomes and swell to 5x their diameter
how long can macrophages last
for months to years and are the first line of defense against infection
the monocyte-macrophage system is also called _____
a system where all tissues show phagocytic properties from tissue macrophages
the reticuloendothelial system
the reticuloendothelial system consists of
the blood, lungs, brain, kidneys, synovial joints, spleen, lymph nodes, and liver
in skin and subq tissues this is the first line of defense
histiocytes
lymph nodes
tissue macrophages line lymph sinuses; trap and destroy invading organisms
liver
kupffer cells destroy bacteria in portal blood from GI tract
alveoli
alveolar macrophages
spleen
effective at removing unwanted organisms and debris from blood (esp old or abnormal RBC)
most numerous leukocyte
first to arrive at site of infection
second line of defense
neutrophils
after they are released into the blood neutrophils (PMN) circulate for _ to _ hours and stay in the tissues _ to _ days
4 to 8 hours for 4 to 5 days
release enzymes and oxygen reactive products lethal to parasites
such as
-schistosomiasis
-trichinosis (trichinella- pork worm)
-elevated in pts with type 1 hypersensitivity reactions and asthma
eosinophils
after their release from the bone marrow, migrate to respiratory tract, GI tract, and superficial layers of skin
basophils
basophils behave like what type of cells
mast cells and release histamine, serotonin, bradykinin, heparin, slow reacting substances of anaphylaxis (leukotrienes), platelet activating factor
s/s of basophils
vasodilation, watery eyes, itching, urticaria, and edema
inflammation causes
vasodilation
increased cap permeability which leads to edema
-leakage of cells out of blood vessels into tissues
-migration of granulocytes and monocytes and activation of tissue macrophages
-area of injury “walled off” from remaining tissue
-after several days, cavitation of necrotic tissue, dead WBC= pus
WBC < 4000 is defined as
leukopenia which is the result of the depression of bone marrow function
causes of leukopenia
- auto immune disease SLE (lupus, rheumatoid arthritis)
-thiouricil
-chemo agents
-phenothiazines
-radiation
-anesthetic agents
WBC < 2000- minor infection
WBC <1,000- serious infections (pneumonia, wound infections)
WBC < 500- life-threatening infections
WBC > 10,000 is defined as
leukocytosis, may be caused by infection, leukemia, mononucleosis, and nonbacterial tissue injury
a shift to the left in leukocytosis means>
more immature (band or blast) cells, known to be with acute infection
shift to the right with leukocytosis means
abnormally large number of mature cells, occurs with chronic infections
cancerous mutations of bone marrow (myelogenous) or lymphoid cells (lymphogenous) are known as
leukemia
leukemia is
uncontrolled productions of WBC and increased # in circulating blood
in leukemia, cancer spreads and WBC produced from aberrant sites such as ___
spleen and liver
