Plasma Flashcards
What are the 4 mains fluid compartments in humans?
- intracellular (55%)
-extracellular (45%)
— blood plasma (7%)
— interstitial fluid (36%) Between cells
— trans cellular fluid (2%) Cerebrospinal, ocular(eyes), synovial
What is the role of interstitial fluid?
Carries O2 and nutrients to cells
Vehicle for the removal of cellular waste products
Where is interstitial fluid drained from?
From tissues by the lymphatic vessels and is known as lymph
Where does lymph drain?
To secondary lymphoid organs such as the lymph nodes
What does lymph play a role in?
It is a component of the adaptive immune response.
What is the composition of plasma?
very similar to interstitial fluid
What is the main difference between plasma and interstitial fluid?
Plasma contains much more protein
What is plasma?
the liquid component of the blood, comprising around 55% of a given blood volume
How do we separate the components of the blood?
Treat the sample with anticoagulant then subject the sample to centrifugation
What are the components of blood?
- Plasma (55%)
- Buffy coat (<1%) — separates RBCs and plasma
- Red Blood cells (45%)
What does the buffy coat consist of?
leukocytes and platelets
What is Apherisis?
a technique in which the blood of a donor is collected and passed through a centrifuge to separate a particular cellular component, with the remained returned to the donor
In this way, different cell fractions can be purified for further use.
What disorders can therapeutic apheresis be used to treat?
- Plasma exchange
- Low density lipid removal
- Red cell exchange
- Platelet depletion
- White blood cell depletion
What does plasma exchange treat?
multiple sclerosis and myeloma
What does low density lipid removal treat?
patients prone to atherosclerosis
What does red cell exchange treat?
Sickle cell disease
What does platelet depletion treat?
Disorders of homeostasis
What does white blood cell depletion treat?
Leukaemia
What is the use of harvesting of peripheral blood stem cells?
Once isolated, these cells are commonly used in bone marrow transplantation, to treat patients with leukaemia and lymphoma (white blood cell cancers).
What is serum?
It is generated by letting blood clot for several minutes, depleting the plasma of coagulation factors and trapping cells and platelets within the clot
What are the differences between serum and plasma
Plasma is relatively quick to prepare whilst serum can generate a cleaner sample (containing few cells) but takes longer to generate
What are the functions of plasma?
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Clotting Immune defence Osmotic pressure maintenance Metabolism Endocrine Excretion
Role of plasma in clotting?
clotting factors and von Willebrand factor found in plasma play keys role in blood clotting
Role of plasma in immune defence?
Contains antibodies and complement protein
Role of plasma in osmotic pressure maintenance?
proteins such as albumin help to maintain colloidal osmotic pressure
Role of plasma in metabolism?
nutrients such as glucose, amino acids and vitamins are transported in the plasma
Role of plasma in endocrine
many hormones are soluble in plasma and following release into the blood travel to their target organs
Role of plasma in excretion?
cell metabolism waste products such as urea are transported via the plasma fraction of the blood to the kidneys for removal
How abundant are proteins in the plasma?
7%
How can we determine the content of plasma?
electrophoresis
What is the most abundant plasma protein?
Serum albumin
Peak lies closer to the cathode
Where is Serum Albumin produced?
The liver
What are the functions of serum albumin?
- Transport of lipids, hormones, ions
2. Maintaining osmotic pressure of plasma
What is the role of albumin?
When fatty acids are released from the breakdown of triglycerides in adipose tissue —> albumin plays a key role in transporting these around the body for use by other tissues in β-oxidation
What are globulins?
Plasma proteins (35%)
What are the 3 groups of globulins?
Alpha globulins
Beta globulins
Gamma globulins
What can alpha globulins be broken down into?
Alpha-1 globulins
Alpha-2 globulins
What are serum alpha 1 globulins represented by?
Alpha-1 antitrypsin (A1AT)
Where is alpha-1 antitrypsin (A1AT) produced and what is its role?
Produced by the liver
Enters the circulation where it plays an important role of inhibiting enzymes which breakdown proteins( proteases)
What does inhibiting proteases by A1AT do?
Protects tissues from a variety of enzymes( notably neutrophil elastase- released by neutrophils during inflammation)
What happens if A1AT is defective or deficient?
Compromises lung where degradation of lung tissue leads to a loss of elasticity & respiratory problems
What are alpha-2 globulins represented by?
Haptoglobin & a2- macroglobulin
How is haptoglobin removed?
Binds to haemoglobin released from erythrocytes and the resulting haptoglobin- haemoglobin complex is removed by the spleen
What can the levels of haptoglobin show?
Diagnosis of haemolytic anaemia
What is the role of a2- macroglobulin?
Broadly active protease inhibitor
Which can inactive fibrinolytic, the breakdown of fibrin involved in blood clotting
What proteins do Beta globulins include?
C3 and C4 complement proteins
Transferrin
What is the role of transferrin and where is it generated?
Generated by the liver
Transportation of iron both dietary and that released from the stores of ferritin
What proteins do gamma globulins include?
Immunoglobulins (antibodies)
Acute-phase protein C-reactive protein
What does an increase in the relative amounts of the gamma fraction of globulins indicate?
Increased immune system activity associated with infection
How much of the plasma do electrolytes make up?
1%
What are electrolytes major contributors to?
Osmolarity
Which is the most plentiful cation in the plasma?
Sodium
Levels 30 times lower inside blood cells
Levels of potassium?
30 times lower outside the red cell
How are cells not being torn apart by difference in charge?
The positive from the intracellular K is mainly balanced by extracellular chloride ions
Also neutralised by anions: proteins, nucleus acids, phosphorylase proteins
Where are calcium ions found?
intracellular levels several thousand times lower than those outside the cell
What are increases in intracellular calcium are associated with?
signalling events and can be due to either the opening of calcium channels allowing influx form the exterior, or the release of intracellular stores
What is intracellular MG important for?
Cofactor for many enzymes
How is the maintenance of electrolyte gradients achieved?
Active transport of ions by protein pumps such as the Na+-K+ pump
What is the Na+-K+ pump also known as?
Na+-K+-ATPase since hydrolysis of ATP is required to provide the energy for transportation
How many K+ ions are transported for every 3 Na+ ions?
2
What is maintaining the gradient of Na+ and K+ is key to?
the functioning of electrically excitable cells e.g. muscle fibres and neurones and also the maintain of cell volume
What happens when ATP levels become depleted?
cells have a tendency to become more spherical because of the inward movement of sodium ions and water
How can passive immunity may be conferred from the donor to the recipient?
if a patient is recovering from a particular infection, then the plasma is likely to contain relatively high levels of polyclonal antibodies which recognise the pathogen –> these are harvested and transferred to patients
