Lecture 16 Flashcards
List the functions of plasma proteins.
- Exert ______ _____ pressure
- Participate in ________/_______ responses and ______ processes
- _______ functions
- Aid in the maintenance of _____/_____ balance
- Exert colloid osmotic pressure
- Participate in immune /inflammatory responses and clotting processes
- Nutritive functions
- Aid in the maintenance of acid base balance
Proteins
* Majority, Synthesized by the _____
* Some Synthesized by _______ system, including (aka examples?)
Liver, immune, Cytokines, Immunoglobulins
Age related changes in plasma and serum protein concentrations occur in ________ and ___.
mammals, birds
Mammals → plasma and serum protein concentrations are low at _____,
* increase after absorption of ______,
* decline over __-__ weeks (_________ is metabolized),
* and then increase to adult levels within __ months.
birth, colostrum, 1-5, colostrum, 6
Total Protein consists of?
1) Albumin
2) Everybody else = Globulins
What is the size of albumin?
- Small: Aprox. 67kDa
Albumin represents 35-50% of the _______ ______ protein concentration
total serum
Where is albumin synthesized?
What is it regulated by?
- Synthesized in the liver:
- Regulated by IL-1 and other cytokines
What is Albumin’s half-life in dogs?
Horses?
Cattle?
- Half-life in dogs → ~8 days
- Half-life in Horses →~ 19 days
- Half-life in cattle → ~2-3 weeks
What is the function of albumin?
- Maintains ________ pressure ~___% of _____ ______ activity of plasma is maintained by albumin.
- In healthy animals, only a very small amount are lost in the ____ tract and _______ ____. Nearly all albumin in ____ ______ are reabsorbed in _____ _______ to continue to maintain normal albumin levels needed.
- Maintains oncotic pressure ~75% of colloidal osmotic activity of plasma is maintained by albumin.
In healthy animals, only a very small amount are lost in the GI tract and glomerular filtrate.
Nearly all albumin in GF are reabsorbed in PT to continue to maintain normal albumin levels needed.
What are the major functions of albumin?
Assist the transport of substances that are _______ soluble; prevent the loss of ______ molecules through the kidney. In healthy individuals, only very small amounts are lost into the ___ tract and the ______ ______ (nearly all of albumin in ______ _______ is reabsorbed in the _______ ______).
* Transports ~ ___% of total serum ______
* _______ ______ source in peripheral tissues
* ________ and _______
* ______ _____ phase protein
This is important to remember, the major albumin functions:
Assist the transport of substances that are sparingly soluble; prevent the loss of small
molecules through the kidney. In healthy individuals, only very small amounts are lost
into the gastrointestinal tract and the glomerular filtrate (nearly all of albumin in glomerular filtrate is reabsorbed in the proximal tubules).
* Transports ~ 40% of total serum calcium
* Amino acid source in peripheral tissues
* Antioxidant and buffer
* Negative acute phase protein
Albumin concentration may affect the concentration of many ?
plasma constituents
What are the two major roles Albumin serves?
- Transport of _________
- _______ _______ pressure
* Maintains _______ pressure ~___% of ________ _______ activity of plasma
* Albumin concentration may affect the concentration of many ?
- Transport of proteins
- Colloidal osmotic pressure
* Maintains osmotic pressure ~75% of colloidal osmotic activity of plasma
* Albumin concentration may affect the concentration of many plasma
constituents
What are globulins? List some examples.
What are they characterized based off of?
Globulins
* Diverse group of proteins with a broad range of functions
* Categorized based on electrophoretic motility
*α-globulins
*β-globulins
*γ-globulins
What sample type do we use for electrophoresis? Serum or Plasma? Why?
For electrophoresis we use SERUM (since fibrinogen can interfere w results)
Where are alpha globulins produced? What function do they serve?
α-globulins
* Produced by the liver
* Primarily act as transport proteins and inactivate proteases
* thus considered anti-inflammatory proteins
Label these peaks below.
Alpha
2nd and 3rd column on electropho?gram.
β-globulins
* Include some _______ proteins and _________ (Ig__ and Ig___) and ________
* Some are synthesized in the ____ (__________); some are produced by __ lymphocytes/plasma cells in response to ______ stimulation (Ig__ and Ig___)
* (3?) are part of this group, but are not present in serum protein fractions
β-globulins
* Include some transport proteins and immunoglobulins (IgM and IgA) and complement C3
* Some are synthesized in the liver (transferrin); some are produced by B lymphocytes/plasma cells in response to antigenic stimulation (IgM and IgA)
* Fibrinogen, prothrombin and plasminogen are part of this group, but are not present in serum protein fractions
Which peak is pictured below?
Beta
4th column
γ-globulins
* Primarily Ig___ antibodies produced by __-lymphocytes/____ cells
G, B, plasma
Which peak is pictured below?
Gamma
List the different ways in which we can measure protein.
- Refractometry
- Biuret Method
- Colorimetric method (automated chemistry analysers) - Turbidometric methods
- Precipitation or dye-binding methods
Refractometry is not an accurate measuring method in birds where the biuret
method is preferred.
Refractometry
* Common method used to measure ___ ____ concentrations in (3?)
** There is a difference in ______ concentration between plasma and serum (due to absence of _______ in serum)
- Common method used to measure total solid concentrations in
plasma, serum and other fluids
** There is a difference in protein concentration between plasma and serum (due to absence of fibrinogen in serum)
Protein molecules refract light [protein] ≈ refractive index
When the T P is reported as a ______/_____ and/or when it is reported on a ____ , it is measured by a REFRACTOMETER
PCV/TP, CBC
TP =?
albumin, globulin
Refractometry may cause?
- Causes FALSE elevated levels, High concentrations (CHUGL):
q Cholesterol/Lipemia,
q hemoglobin,
q urea,
q Glucose - Sodium chloride may cause falsely high levels
Bilirubin alters the ____ but not the ____
color, reading
Which analytes are reported in the chemistry analyzer?
She said this is an important slide.
Concentration is typically measured by subtraction
Ø Total protein – albumin= globulin
* Different globulin fractions may be separated and measured using ?
serum protein electrophoresis (SPE)
Serum is the ideal sample for electrophoresis because?
It does not contain fibrinogen
How does SPE determine protein factors?
- SPE separates proteins into multiple bands based on the ____ and ____ of the protein, ____ of protein, and the _______ of electrical field, ____ of supporting medium, and _____.
- Protein bands are translated by a ________ into a tracing
- Commonly performed to distinguish between hyperglobulinemia caused by an ______ and/or ______ immune response FROM hyperglobulinemia caused by ?
- SPE separates proteins into multiple bands based on the size and charge of the protein, shape of protein, and the strength of electrical field, type of supporting medium, and temperature.
- Protein bands are translated by a densitometer into a tracing
- Commonly performed to distinguish between hyperglobulinemia caused by an innate and/or acquired immune response from hyperglobulinemia caused by neoplastic lymphoid proliferation
Protein Measurement: Electrophoresis
* Results are reported as a
electrophoretogram For each protein (alpha, beta, gamma):
* Percentage (%)
* Absolute amount (g/dL)
Albumin
* ___________ protein (69 kDa)
* Highest net __________ charge
* Migrates ________ & __________ in the y axis
Smallest
negative
fastest, furthest
Globulins
* ________, do not migrate as ___
* γ globulins, ________ negative charge;
migrate the _________ distance
Larger, far, weakest, shortest
Protein Abnormalities are also called?
(Dysproteinemias)
Protein abnormalities:
hyperproteinemia
hyperfibrinogenemia
hypoproteinemia
ALBUMIN
hyperalbuminemia
hypoalbuminemia
GLOBULIN
-hyperglobulinemia
fibrinogen
serum amyloid A
C-reactive protein (CRP)
polyclonal gammopathies
monoclonal gammopathies
hypoglobulinemia
Hyperproteineimia is characterized by?
Hyperproteinemia
Total protein
* Increased total protein concentration
* Increased globulin production (this makes it real hyperproteineimia)
Artifactual increase
* Hemolysis
* Lipemia
What is a relative hyperproteinemia?
Hypoproteinemia
* _________ _____ protein concentration
* Feature of conditions such as ? (_______ derm = losing protein through inflammatory process)
* Relative cases → ________ of plasma proteins by ______ fluid (excess fluid therapy)
* Look at the PCV to have best interpretation of hypoproteinemia
- Decreased total protein concentration
- Feature of conditions such as burns, gastrointestinal disease (protein-losing enteropathies), exudative dermatopathies and whole blood loss (exudative derm = losing protein through inflammatory process)
- Relative cases → dilution of plasma proteins by excess fluid (excess fluid therapy)
- Look at the PCV to have best interpretation of hypoproteinemia
Hyperalbuminemia
* _________ albumin concentration
* Almost always associated with _______ (or ______)
* Mild increases in albumin may occur in dogs given __________ therapy, the mechanism for which is ______ (suggested mechanisms include increased _______ or increased albumin ___ ____)
Artifactual increase –> ?
- Increased albumin concentration
- Almost always associated with dehydration (or artifact)
- Mild increases in albumin may occur in dogs given glucocorticoid therapy, the mechanism for which is unknown (suggested mechanisms include increased synthesis or increased albumin life span)
Artifactual increase
* Hemolysis
* Lipemia
In what situations would you see hypoalbuminemia?
- Decreased production of albumin
- Increased loss or catabolism of albumin
- Increased loss or catabolism of albumin and globulin
- Fluid therapy (dilutional)
Diminished production of albumin → seen in ? Not a consistent finding in horses with?
pregnancy, lactation, intestinal malabsorption, malnutrition, cachexia, neoplasia, exocrine pancreatic insufficiency, and chronic liver disease
liver disease
List the causes of decreased production of albumin.
- Maldigestion
- Malabsorption
- Malnutrition
- Catabolic states
- Advanced hepatic disease
- Hyperglobulinemia
How does malabsorption/maldigestion –> hypoalbuminemia?
inadequate absorption of _____ ______ or inadequate digestion of dietary _______ may lead to a deficient supply of _____ _____ and
decreased _______ production.
Malabsorption syndromes include ______ intestinal disease with generalized ________ involvement.
Maldigestion includes (2?).
In these cases, globulins may be ______ or _______
inadequate absorption of amino acids or inadequate digestion of dietary proteins may lead to a deficient supply of amino acids and
decreased albumin production. Malabsorption syndromes include small intestinal disease with generalized mucosal involvement; maldigestion includes exocrine pancreatic insufficiency or pancreatic atrophy. In these cases, globulins may be normal or decreased
How does malnutrition/cachexia –> hypoalbuminemia?
severe prolonged malnutrition/starvation and cachectic
states lead to a deficiency in the supply of amino acids, so protein synthesis is
decreased. Initially, glucose and protein concentration is maintained at the expense
of other tissues, but once fat and muscle mass are depleted, protein concentration
decreases too. This decrease in albumin normally only occurs at the end stage of
starvation that has been severe and prolonged. In these cases, globulins may be
normal or decreased.
Which catabolic states –> hypoalbuminemia?
Pregnancy, lactation, malignant neoplasia
How does advanced hepatic disease –> hypoalbuminemia?
a marked decrease (> than 80%) in functional hepatic mass will lead to decreased synthesis of all plasma proteins (except immunoglobulins).
How does hyperglobulinemia –> hypoalbuminemia?
Increased production of γ-globulins leads to decreased production of albumin through an unknown mechanism.
Suggested mechanisms include inflammatory cytokines decreasing albumin synthesis or that low albumin occurs as a compensation for the high globulins in order to maintain colloid osmotic pressure and plasma viscosity within normal limits
Horses with _____ disease do not have consistent finding of hypoalbuminemia, but other species do. Take note!
liver
How does Increased loss or catabolism of albumin lead to hypoalbuminemia?
- Renal disease with chronic proteinuria (protein losing nephropathies)
- Severe exudative skin diseases
- e.g. burns
- Ascites
- accumulation of fluid in abdominal cavity
- Hypoadrenocorticism
Renal glomerular damage can lead to protein loss through glomerular filtrate.
What conditions –> Increased loss or catabolism of albumin and globulin–> hypoalbuminemia?
- Acute and chronic hemorrhage
- Protein-losing enteropathies
- Severe loss of plasma
- Burns
- Severe exudative inflammatory disorders
What are some examples of Accelerated loss ?
haemorrhage
proteinuria of renal disease
protein losing enteropathy
exudative skin burns
intestinal parasitism
high protein effusions
Nephrotic syndrome → hypoalbuminemia, azotaemia, and hypercholesterolemia.
Once plasma albumin concentrations fall below a threshold level (~ 15 g/L), the
colloid osmotic pressure drops and fluid is lost into tissues or body cavities, resulting
in ascites, hydrothorax, hydropericardium, pulmonary and edema
Albumin and calcium
About 40% of calcium in plasma is bound to albumin. As a result, the total
serum/plasma calcium concentration in animals with hypoalbuminemia will be
reduced.
List the causes of hyperglobulinemia.
1) Hemoconcentration
2) Increased globulins (a, b)
3) Increased g globulins
a) Polyclonal
b) Monoclonal
If serum globulins are increased, _______ ___________ is indicated
protein electrophoresis
Hyperglobulinemia
Most commonly due to _______ but may be due to increased concentration of one or more of the globulin fractions (due to ?).
During inflammation, the release of inflammatory cytokines such as?, leads to increased production of certain globulins by _______ and increased production of immunoglobulins by ______. This acute phase response is part of the ____ immune system.
dehydration
infection, inflammation, or/and neoplasia
IL-1, IL-6, IFN-γ and TNF-α
hepatocytes, lymphocytes, innate
Acute phase proteins (APPs)
* Plasma proteins that are increased (+) or decreased (-) during an __________ response due to any type of ?
* An increase in the acute phase proteins leads to _________ and _______ depending on the magnitude of the increase
- Plasma proteins that are increased (+) or decreased (-) during an inflammatory
response due to any type of injury, infec=ous or non-infec=ous - An increase in the acute phase proteins leads to hyperglobulinemia and
hyperproteinemia depending on the magnitude of the increase
- Most APPs are __-globulins, but some are __-globulins
- APPs play a role in the ________ response, protect against ________ _______ and have
____-______ properties - APPs production is stimulated by ? and other cytokines
- Hepatic synthesis of APPs occurs 24 hrs after _____ tissue injury
(APPs are also produced in response to ?)
- Most APPs are α-globulins, but some are β-globulins
- APPs play a role in the immune response, protect against oxidative stress and have
anti-infective properties - APPs production is stimulated by IL-1 β, IL6 and TNF and other
cytokines - Hepatic synthesis of APPs occurs 24 hrs after acute tissue injury
(APPs are also produced in response to physical stress, or corticosteroid
administration)
- APPs can be classified into _____, ________ and _______, depending on the _______ and ________ of the increase
- Major APPs increase in concentration by ____-____ times after stimulation and reach a
peak in ____-____ hours, falling rapidly on recovery - Moderate APPs increase by __-__ times their normal concentration, reach a peak At
__-__ days, and decrease more _____
- APPs can be classified into major, moderate and minor, depending on the speed
and magnitude of the increase - Major APPs increase in concentration by 100-1000 times after stimulation and reach a
peak in 24-48 hours, falling rapidly on recovery - Moderate APPs increase by 5-10 times their normal concentration, reach a peak At
2-3 days, and decrease more slowly
List the major APPs for the following species:
1. Cat
2. Dog
3. Horse
4. Cow
5. Pig
List the moderate APPs for the following species:
1. Cat
2. Dog
3. Horse
4. Cow
5. Pig
See below
Fibrinogen (Fb)
* Best known of the _____ _____ proteins
* Produced in ______
* Increases may occur in ?
* In cattle, fibrinogen is a more sensitive indicator of _______ than the total _____ blood cell count
* Useful in ______ too and possibly ____
- Best known of the acute phase proteins
- Produced in liver
- Increases may occur in acute and chronic inflamma1on, >ssue damage and
some cases of neoplasia - In ca2le, fibrinogen is a more sensi1ve indicator of inflamma1on than the total
white blood cell count - Useful in horses too and possibly dogs
Fibrinogen It is a ________ Acute Phase Protein, and considered a _____ responder, but
because it composes ~___% of total plasma protein, it represents the greatest
proportion of plasma protein produced during an _____ phase response.
Fibrinogen It is a moderate Acute Phase Protein, and considered a late responder, but
because it composes ~5% of total plasma protein, it represents the greatest
proportion of plasma protein produced during an acute phase response.
Hypofibrinogenemia
* _____ failure (decreased production)
* DIC (________)
Liver, consumption
Serum amyloid A (SAA)
* ______ acute phase protein for many species
* Considered ______ reactive APP
* Increases in SAA peak ___ days after injury and return to normal within ?
* In horses it is useful for diagnosing _________, monitoring the _______ of therapy, monitoring ____-operative recovery and possibly gives information on _________
* In cattle and dogs, the magnitude of increase in SAA is thought to be related to the
________ of inflammation
- Major acute phase protein for many species
- Considered rapid reactive APP
- Increases in SAA peak 2 days after injury and return to normal within 5 to 7 days
- In horses it is useful for diagnosing inflammation, monitoring the efficacy of therapy, monitoring post-operative recovery and possibly gives information on prognosis
- In cattle and dogs, the magnitude of increase in SAA is thought to be related to the
severity of inflammation
C-reactive protein (CRP)
* _____ acute phase protein in the dog that is produced in the _____
* Concentrations in healthy dogs are _____ but marked increases occur rapidly in response to _____ inflammation
* Concentrations decrease rapidly with ___________ of inflammation
- Major acute phase protein in the dog that is produced in the Liver
- Concentrations in healthy dogs are low but marked increases occur rapidly in response to acute inflammation
- Concentrations decrease rapidly with resolution of inflammation
Increase in serum globulins
* In the acute phase reaction, initially increased concentrations of __ and __-globulins may be seen on serum protein electrophoresis
* As the inflammation becomes more chronic, ________ may decrease, __ and ___-globulins may be increased, and a broad-based peak of increased ___- globulins known as a polyclonal gammopathy may be seen.
- In the acute phase reaction, initially increased concentrations of a and
b-globulins may be seen on serum protein electrophoresis - As the inflammation becomes more chronic, albumin may decrease, a and b-globulins may be increased, and a broad-based peak of increased g- globulins known as a polyclonal gammopathy may be seen
Polyclonal gammopathies are:
* Characterized by an _______ globulin fraction with a _______-based electrophoretic peak composed of a heterogeneous mixture of immunoglobulins
* Commonly seen in ?
* A profound polyclonal peak occurs in cats with _____. The polyclonal peak has a base width _____ than the base width of the albumin peak
- Characterized by an increased globulin fraction with a broad-based electrophoretic
peak composed of a heterogeneous mixture of immunoglobulins - Commonly seen in chronic inflammatory diseases, immune- mediated diseases, and liver disease
- A profound polyclonal peak occurs in cats with feline infectious peritonitis. The polyclonal peak has a base width wider than the base width of the albumin peak
Monoclonal gammopathies
* Characterized by an ________ globulin fraction with a _____-based electrophoretic peak that is not _____ than the albumin peak
* Monoclonal gammopathies may occur when a single clone of usually _______lymphoid cells produce immunoglobulins with _______ structure
* Most commonly seen with ?
In conjunction with the monoclonal gammopathy on serum protein electrophoresis, the albumin peak may be _______ due to hyperviscosity syndrome in order to try and reduce _____ ______ _____. Animals may also have ______-_____ ______, where immunoglobulin light chains are excreted in the urine.
- Characterized by an increased globulin fraction with a narrow-based electrophoretic peak that is not wider than the albumin peak
- Monoclonal gammopathies may occur when a single clone of usually neoplastic lymphoid cells produce immunoglobulins
with identical structure - Most commonly seen with lymphoid neoplasia (lymphoma, plasma cell myeloma)
In conjunction with the monoclonal gammopathy on serum protein electrophoresis, the albumin peak may be decreased due to hyperviscosity syndrome in order to try and reduce colloid osmotic pressure. Animals may also have Bence-Jones proteinuria, where immunoglobulin light chains are excreted in the urine.
Monoclonal gammopathy
* Narrow-based electrophoretic peak that is not wider than the ______ peak
albumin
Hypoglobulinemia is seen in?
* ______ production (E.g. ? syndrome (_____))
* Abnormal loss Hemorrhage (E.g. ? (_____))
* Failure of _______ transfer (___) in neonates
* Impaired synthesis of immunoglobulins occurs in some rare ______ diseases (e.g. ?) or ________ immunodeficiency diseases may also cause hypoglobulinemia.
- Decreased production
- Severe combined immunodeficiency syndrome (SCIDS)
- Abnormal loss Hemorrhage
- Protein-losing enteropathy (PLE)
- Failure of passive transfer (FPT) in neonates
- Impaired synthesis of immunoglobulins occurs in some rare genetic diseases (e.g. severe combined immunodeficiency of Arab and. Appaloosa horses) or acquired immunodeficiency diseases may also
cause hypoglobulinemia.
Commonly occurs with hypoalbuminemia leading to panhypoproteinemia in
association with hemorrhage, protein-losing enteropathies, exudative diseases,
maldigestion/malabsorption or malnutrition
Failure of passive transfer leads to very low γ-globulin levels at birth. In a neonatal
animal, hypoglobulinemia usually reflects inadequate absorption of colostral
antibodies (failure of passive transfer).
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