Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
23 Cards in this Set
- Front
- Back
|
Where do lymphocytes develop?
|
lymphoid tissues, including bone marrow, thymus, lymph nodes, spleen
|
|
|
How do lymphocytes travel between tissues?
|
use blood. Enter blood via thoracic duct
|
|
|
What are the majority of lymphocytes in peripheral blood?
|
T cells
|
|
|
Where do you find lymphocytes in blood?
|
circulating and marginating pools
|
|
|
What is the fn of lymphocytes?
|
In tissues (i.e. LN), if proper antigen presented to lymphocyte, undergoes lymphoblastogenesis and produce antibody (B cells, plasma cells) or cytokine (T cells, cytotoxic T cells), or may serve other fn (help and suppression). Sometimes lymphocyte undergone lymphoblastogenesis in tissues enter blood and recognized as 'reactive lymphocytes' on blood smear
|
|
|
What is morphologic appearance of lymphocytes?
|
'mature' or 'quiescent' appearance: smaller than neutrophils and high N:C ratio w/ scant cytoplasm. Chromatin condensed, cytoplasm pale blue. Smaller than neutrophils
|
|
|
What do azurophilic granules in lymphocytes mean?
|
either cytotoxic T cells or natural killer cells
|
|
|
What are reactive lymphocytes?
|
antigen stimulated. large w/ basophilic cytoplasm. nucleoli may be visible. Usually in lymphoid organs
|
|
|
What is lymphocytosis?
|
increased concentration of lymphocytes in blood
|
|
|
What are causes of lymphocytosis (4)
|
-chronic inflammation
-physiologic lymphocytosis -absence of glucocorticoids -lymphocytic leukemia *younger animals have higher lymphocyte count |
|
|
Describe lymphocytosis ass w/ chronic inflamation (3 things)
|
-may be seen when antigenic stimulation during chronic inflammation and usually accompanied by neutrophilia and monocytosis
-reactive lymp may seen in peripheral blood smear -lymphoid hyperplasia can occur even when lymphocytosis not present in peripheral blood |
|
|
Describe physiologic lymphocytosis (3 things)
|
-catecholamine release from fear or excitement causes lymphocytes to shift from marginating to circulating pool in blood and to enter circulation from spleen
-lymph count no more than 2x URI, effect is transient -cats and foals most freq affected |
|
|
Describe lymphocytosis from absence of glucocorticoids
|
endogenous glucocorticoids (cortisol) influence dist of lymph in body and have inhibitory effect of lymph prod. absence of glucocort (seen in animal w/ hypoadrenocorticism) lymph count may be normal or increased in stressed animal in which lymphopenia would be expected
|
|
|
Describe lympocytic leukemia
|
most common form of leukemia in domestic animals. Several forms of leukemia. Lymph counts extremely high and may have morphologic abnormalities
|
|
|
What is lymphopenia?
|
decreased concentration of lymphocytes in blood
|
|
|
What are the causes of lymphopenia? (4 things)
|
-glucocorticoid ass lymphopenia (stress)
-acute inflammation -loss of lymphocytes -lymphoid hypoplasia or aplasia |
|
|
Describe glucocorticoid ass (stress) lymphopenia (3 things)
|
-mech is
a. redist of lymp in bone marrow (rather than blood) b. failure of lymphocytes to exit LN -glucocorticoids can be lympholytic and destruction of lymphocytes may play role in lymphopenia if stress long stnading -stress lymphopenia induced by glucocorticoid is most common form of lymphopenia, and lymphopenia most freq manifestation of stress in leukogram |
|
|
Describe lympopenia ass w/ acute inflammation (2 things)
|
-lymph migrate from blood into affected tissues and enter LN at higher rates. Egress of lymp from LN reduced
-lymphopenia used as prognostic indicator, return of lymp count to normal is sign of improvement |
|
|
Describe lymphopenia caused by loss of lymphocytes
|
lymph depleted from body in lympocyte rich fluids lost
ex lymph into GI tract in animlas w/ lymphagniectasia |
|
|
Describe lymphopenia ass w/ lymphoid hypplasia/aplasia
|
immunodeficiency syndromes, both congenital and acquired forms, exist in animals and animals may seem lymphopenic
ex. Arabian horses w/ congenial severe combined immunodeficiency (SCID) may be decreased lymphocte counts |
|
|
What happens to your lymphocyte count as you get older?
|
It decreases
|
|
|
What will accompany chronic antigenic stimulation (lymphocytosis due to chronic inflammation)?
|
neutrophilia and monocytosis
|
|
|
What will a dog with stress exhibit in his cells?
|
neutrophilia, monocytosis, lymphopenia
|
