L15. Blood Flashcards
What is blood?
Specialized connective tissue
What does blood consists of?
Formed elements= (45% of RBC) Cells+Platelets
(1% of buffy coat consists of platelets an WBC)
ECM= Plasma
55% of Plasma:
90% water, 9% protein
1% dissolved ions and gases
What are the 5 types of plasma proteins
- Albumin
- Globulins
- Clotting Protein
- Complement proteins
- Plasma lipoproteins
Where is the source of most of the plasma proteins?
liver
What does high levels of LDL indicate?
hypercholesterolemia
What do you get when you remove clotting factors from plasma?
serum
What is the function of albumin?
maintains colloid pressure and transports certain insoluble metabolites
What is the function of complement proteins?
destruction of micro-ogranisms and initiation of inflammation
What is the function of plasma lipoproteins?
transport triglyceriods and cholesterol from the liver to other body cells ( or to the liver )
What is the hematocrit?
It consists of the formed elements ( RBC, WBC and platelets)
Can the buffy coat composition change? If so when
Yes it can change during extreme pathological conditions
What stain is used to stain blood
Wright stain
In a Wright stain what are the colors seen and what do they stain?
blue= acid
pink=protein
purple=glycoprotein
Describe the shape and nucleus type of erythrocytes
-biconcave disc
-no nucleus
-stains wright pink because hemoglobin is acidophillic ( so it is actually basic)
~8um in diameter
-biconcave in shape ( increases -SA for gas exchange)
-few organelles
- has sub-plasmamembranous cytoskeleton
- has surface carbohydrates
What is the functions of RBC?
transport hemoglobin and binds O2 and CO2
functions inside circulatory system
What is anemia?
RBC deficiency
can be
-metabolic ( iron deficiency)
- genetic ( sickle call anemia)
What is in the cytoplasm of RBC
- packed with Hb
- protein +iron/heme group
- contains carbonic anhydrase enzyme
What are the carbohydrates on the surface of RBC for?
Used for surface antigens.
AB universal acceptor
O universal donor
What is the purpose of the plasmamembranous cytoskeleton
- maintains RBC shape and flexibility
- needed for the RBC movement through the capillaries
Write the equation in the RBC involving carbonic anhydrase
H2)+CO2-> H2CO3 ( this is catalyzed by carbonic anhydrase)-> H+ + HCO3- ( this is caused by alkali RBC)
What is the function of producing bicarbonate ions?
- used to buffer
- used to carry CO2
What is the lifespan of a RBC?
120 days
When/ How does RBCs break down?
- loss of cytoskeletal integrity
- slows RBC movement in vessels + fragility
- RBC degradation in the spleen
What is the % composition of proteins on the RBC
50%
What are the 2 main proteins found on the RBC
glycophorins=membrane anchors for cytoplasmic adaptor/ linker complexes
band 3=membrane anchors for anion transporter (ie. for HCO3)
Can the RBC make proteins
No, has no nucleus
What is the percentage composition of WBC in the blood
less than 1% of total cell number
What are the functions of WBC
- travel in the circulatory system
- function outside of the circulatory system
- exit the vasculature by integrin-dependent ‘Diapedesis’
What are the 2 general types of WBC ?
- Granulocytes
- Agranulocytes
What are the types of Granulocytes
- Neutrophiles
- Basophiles
- Eosinophiles
What is the function of granulocytes
- needed for low specificity innate immunity
- cytoplasm of granulocytes contain characteristic cytoplasmic granules
- have cell-type specific =secretory vesicles
What are the characteristics of neutrophils
- short lived
- hours of circulation
- days in CT after diapedesis
- 1st responders during innate immune response
Describe the nucleus in neutrophils
segmented 3-5 lobes, densely stained
Describe the cytoplasm in neutrophils
pale, fine granular, evenly dispersed specific granules
- vesicles have anti-bacterial enzymes
- have many lysosomes
- golgi complex
What are the functions of neutrophils
- phagocytes bacteria ( phagoctic when activated)
- generate pus when they swell and die after digesting bacteria
- increases in the acute bacterial infections
What is the composition of Basophiles in WBC
-less than 1 % of of WBC in circulation
What is the diameter of basophiles
10-14 um
What is the diameter of neutrophiles
9-12 um
Describe the nucleus of the basophile
- blobed/segmented nuclues
Describe the cytoplasm of the basophile
- the vacuoles are acidic so they are attract basophillic stains, large blue specific granules that stain basic dyes
- granules have histamine, heparin, chemoattractants that they release to attract other granulocytes to amplify response
What are the functions of basophiles
- increases vascular permeability
- involved in anti-coagulatoin
Describe the lifespan of basophiles
1-2 years in connective tissues: initiate /amplify innate immune response
What happens when basophiles come together with mast cells?
- de-granulation of basophiles occur
- causes anaphylactic shock due to widespread vasodilation, causes edema and shock ( decreased blood volume) as well as constriction of smooth muscles
What can be used to counteract an Anaphylactic shock?
-epinephrine counteracts vasodilation and relaxing the brinchiolar smooth muscle
What is the % composition of eosinophiles?
2%
What is the lifespan of eosinophiles?
1-2 weeks in connective tissue
Describe eosinophiles
- pink eosinophillic
- dense-cored granules
- active in late stages of innate and adaptive immune response
Describe the cytoplasm of eosinophiles
- large homogenous and granules that are coarse and highly refractile
- pink granules with interum = crystalized core
- golgi complex present
What are the functions of granules in eosinophiles
- pink granules with interum = crystalized core
- contain Major Basic Protein that permeabilizes the membranes of parasites
- Histaminase that dampens innate immune response
- phagocytoses neutralized antigens/ antibody complexes and destroys them during the end stage of a specific adaptive immune response
What are the 2 types of argranulocytes
- monocytes
2. lymphocytes
What are characteristics of agranulocytes
- few cell type-specific granules by LM
- do have some non-specific granules =lysosomes
What are monocytes
- largest circulating blood cell (12-20
- exit circulation by ‘diapedesis’ (migrate through blood vessel wall)
- differentiate into macrophages in connective tissue
What is the % composition of monocytes in WBCs?
5%
Describe the nucleus of the monocytes
-indented kidney shaped, lightly stained
What are the functions of the monocytes
- is motile
- gives rise to macrophages
- phagocytic: operate throughout innate immune reponse
- APC (antigen presenting cells) help initiate adaptive immune response
Describe the cytoplasm of the monocytes
- agranular
- pale blue cytoplasm
- has lysosomes
Where are monocytes activated?
They are activated in the connective tissues to form macrophages
What is the % composition in lymphocytes?
25% of WBC
Describe the nucleus of the lymphocytes?
small, round, slightly indented darkly stained
Describe th cytoplasm of the lymphochytes
agranular, faintly basophilic, blue to grey
-pale rim of cytoplasm in unactivated lymphocytes
What are the different types of lymphocytes, what are their functions
involved in adaptive immunity (response to foreign antigens)
B lymphocytes: humoral/secreted antibody-mediated adaptive immunity
T lymphocytes: cell-mediated adaptive immunity
What are platelets?
- membrane bound cell fragments
- no nucleus
- contains granules/secretory vesicles
- contains integrins and cytoskeletal elements
- in free floating cicrulating blood
Where are platelets derived from?
produced in megakaryotes in the bone marrow
What are the functions of platelets?
-blood clotting, hemostasis
Describe how platelets are activated
- platelets integrins bindto sub-endotehlial collagen in wounded blood vessels
- collagen binding and paracrine signals released from the wounded blood vessel epithelium ( von willebrand factor) activate the platelets
- activation causes platelet aggregation and cytoskeletal contraction of actin and myosin associated with the microtubular ring which leads to tubular system eversion to produce protrusive psudopods and massive vesicle exocytosis of factors (thrombospodian and platelet 3 factors)
what is a von willebrand factor
it is the signal released by the blood vessel epithelium to activate platelets
What are thrombospondin
increase platelet-platelet aggregation to generate a platelet plug
What are platelet factor 3
facilitates a clotting cascade to generate fibrin ‘fibers’ from soluble fibrinogen in the plasma which the platelets also bind to via integrins
What is thrombasthenia?
It is the loss of function mutations in platelet integrins leads to coagulopathies
What is coagulapathies
lack of clotting
What are megakaryotes?
large cells, a lot of nucleus
What is Ankyrin and Band 4 proteins
adaptor linkers to the RBC cytoskeleton
needed to maintain RBC shape and flexibility
