lecture 15+16 Flashcards
Development of the RBC
proerythrocyte
reticulocyte
erythrocyte (once in circulation)
characteristics of the RBC
biconcave disk = max surface area and allows flexibility
no nucleus or organelles
stains with eosin
when stained the middle is not stained, thus white spot in the middle of RBC
What are the azurophilic granules found in all leukocytes
elastase
collagenase
myeloperoxidase
characteristics of neutrophils
granulocyte
nucleus can have multiple lobs, once they age it looks like a horseshoe
function of neutrophils
fastest response to bacteria
phagocytose
can release lysozymes to destroy bacteria
can release defensin to poke holes in bacterial cell walls
can release oxidants to destroy bacteria
characteristics of eosinophils
granulocyte
nucleus is bi-lobed
cytoplasm has large granules
4 major proteins: major basic protein, eosinophil cationic protein, peroxidase, and eosinophil-derived neurotoxin
function of eosinophils
leave the capillaries to enter tissues
go after protozoans and parasites
can release histaminase to neutralize histamine
release arylsulphatase to neutralize leukotrienes
characteristics of basophils
granulocyte
diameter is 10-12um
nucleus bi-lobed and irregular shaped
large granules in cytoplasm (goes over nucleus)
function of the basophil
heighten the inflammatory response and account for hypersensitivity
leave capillaries and enter CT
release:
heparin- anticoagulant
histamine: vasodilation
leukotrienes: constriction of SM in airways
interleukin 4+13: promote synthesis of IgE AB
lymphocyte characteristics
Agranulocyte
nucleus is dark and round
cytoplasm is narrow
can be found in the lymph
lymphocyte function
T cells: differentiate in the thymus
cell-mediated immunity
long life span
attack viruses, fungi, transplanted organs, cancer cells, and some bacteria
B cells: first seen in bone marrow
production of antibodies
destroy bacteria and their toxins
turn into plasma cells
NK cells:
attack many different microbes and some tumor cells
directly attack invaders
monocyte characteristics
Agranulocyte
nucleus is indented and kidney shaped
cytoplasm is a foamy gray
largest WBC
Monocyte functions
take longer, but have more
can go into tissues during inflammation
phagocytose bacteria, dead cells, and tissue debris
increased during viral and fungal infections
Development of thrombocytes (platelets)
megakaryoblasts
magakaryocyte
thrombocyte
thrombocytes kinds
alpha granules:
clotting factors
dense granules:
ADP, ATP, Ca, serotonin, fibrin-stabilizing factor, and thromboxane A2
Thrombocyte functions
blood clot formation (hemostasis)
clot retraction and repair injuries
amount of RBC per gender
male: 5.5 million per uL
female: 4.8 million per uL
leukocyte amount
6000-10000uL
neutrophil amount
5000 uL (60-70%)
eosinophil amount
150 uL (2-4 percent)
basophil amount
30 uL (0.5%)
lymphocyte amount
2400 uL (20-25%)
monocyte amount
350 uL (2-8%)
platelet amount
250,000-400,000 per mm3
Anisocytosis
the RBC’s are unequal sizes
poikilocytosis
the presence the poikilocytes in the blood, which are RBC that have a distorted shape
these cells must make up 10% or more of the blood cell population
cause:
membrane abnormalities
sickle cell anemia
Genetic defect in hemoglobin molecule (Hb-S):
hydrophilic glutamic acid is replaced by hydrophobic
valine at point 6 in β chain
Hereditary spherocytosis
Caused by variety of molecular defects in the genes that code for spectrin, ankyrin, band 3 and band 4 proteins
results in a spherical shape of the RBC
Thalassemia
hereditary hypo-chromatic anemia
beta-thalassemia: decreased or absent beta chains, this leads to an excess of alpha chains. unable to form tetramers.
can lead to aggregation
polycythemia
excessive amount of RBC’s
thrombocytopenia
little amount of platelets
increase in different WBC types
neutrophils increase during acute bacterial infection
lymphocytes increase during chronic infection and cancer
monocytes increase during fungal and viral infection
eosinophil increases during parasitic infection
basophils increase during allergic reactions
assembly of CM and release into the lymph
- intestinal epithelial cells from CM containing dietary lipids and release them into the lymph
- assembly of apo B-48 with lipids inside the cells need MTP
- both apo B-48 and MTP are needed for the CM release into the lymph
LPL enzyme
This enzyme is anchored in the capillaries of the heart, muscle, and adipose tissue
this enzyme cleaves TAG’s inside the lipoproteins
the released fatty acids are used by the heart, muscle, and fat cells
LPL needs activation by apo C-II which it gets from chylomicrons and VLDL’s
What enzyme is insulin dependent?
LPL is activated by insulin
How are the TAG’s in IDL’s cleaved
they are cleaved by hepatic lipase which is anchored in hepatic capillaries and forms LDL
how are TAG’s in VLDL cleaved
cleaved by LPL to form IDL
apo B-48
needed for the synthesis and release of CM into the lymph
apo B-100
Is needed for synthesis and release of VLDLs into the blood and is needed for recognition by the LDL receptor
apo-E
Apo E is needed for recognition by the hepatic remnant receptors and for the uptake of chylomicron remnants and IDLs into the hepatocytes.
given to CM by VLDL and HDL
apo C-II
Apo C-II activates lipoprotein lipase which cleaves TAGs in chylomicrons and VLDL
given to CM by VLDL and HDL
apo A
is needed for the reverse cholesterol transport of HDL.
MTP deficiency
abetalipoproteinemia
impairs fat absorption
loss of functional apo B
hypobetalipoproteinemia
low levels of LDL due to apo B levels being low
Apo E deficiency
Hyperlipoproteinemia Type III (Dysbetalipoproteinemia)
high levels of chylomicron remnants and IDLs
Apo C-II deficiency
Hypertriacylglycerolemia
(hyperlipoproteinemia Type I, IV and V)
high levels of CM and VLDL
oxLDL
not recognized by the LDL-receptor
The scavenger receptor (SR-A) in macrophages allows uptake of oxLDL and leads to “ foam” cells that can release proinflammatory mediators.
increases risk of atherosclerosis
