Serum Proteins and Associated disorders

Question 1

Components of blood plasma

Answer 1

Non-cellular liquid layer of the blood obtained by sedimentation and centrifugation

Question 2

Blood serum (prepared in laboratory)

Answer 2

Whole blood is allowed to coagulate before centrifugation. The resulting fluid is blood serum. Blood serum is blood plasma without blood coagulating factors

Question 3

Function of albumin

Answer 3

1) Maintenance of osmotic pressure
2) Transport: calcium ions, free fatty acids, bilirubin, hormones and drugs
-Extensively synthesized in the liver and released into the blood
-Small and the most abundant serum protein
3) Binding and transport of calcium ions in the blood

Question 4

Function of alpha and beta globulins

Answer 4

1) Enzymes
2) Transport
3) Inhibitor proteins

Question 5

Function of gamma-globulins

Answer 5

Immune response

Question 6

2 Causes of hypoaluminemia

Answer 6

1) Decreased synthesis of albumin: Kwashiorkor, Liver cirrhosis
2) Increased loss of albumin: Kidney disease-loss into urine due to damage of glomerulus basement membrane, Severe burns–damage of blood vessels leads to huge loss of serum

Question 7

Alpha-1 globulin fraction includes:

Answer 7

1) Alpha-1 antitrypsin (>90%)
2) Alpha Fetoprotein (AFP)
3) Transcortin
4) Retinol binding protein

Question 8

A reduced amount of alpha1-Antitripysin in the blood can lead to:

Answer 8

Excessive degradation of elastin in the lung and to emphysema

Question 9

Hereditary deficiency of alpha1-Antitrypsin results from a defective:

Answer 9

Hepatic N-glycosylation and reduced release into the blood. This can lead to pulmonary and liver disease

Question 10

Elevated neutrophil elastase:

Answer 10

Destroys elastin in the alveoli

Question 11

Alpha fetoprotein (AFP) function and type of globulin

Answer 11

AFP is an alpha-globulin that is abundant in fetal plasma which has very low levels of albumin. It may have a function similar to albumin in fetal life. AFP level is low in healthy adults but it increases in cancer and is used as a serum marker for liver cancer.

Question 12

High maternal serum AFP level may be an indicator of:

Answer 12

Neural tube defects (NTD)

Question 13

Low maternal serum AFP level may be an indicator of

Answer 13

Down Syndrome

Question 14

Transcortin and retinol-binding protein are what kind of globulins:

Answer 14

Alpha1-globulins that transport specific lipids in blood

Question 15

Function of retinol-binding protein:

Answer 15

Transports retinol (vitamin A) in blood from the liver to the peripheral tissues

Question 16

Transcortin function

Answer 16

alpha-1 globulin: transports 75% of cortisol in blood

Question 17

Retinol-binding protein function

Answer 17

Retinol (Vitamin A) transport in blood from the liver to the peripheral tissues

Question 18

The alpha-2 globulin fraction

Answer 18

1. Alpha-2 Macroglobulin
2. Ceruloplasmin
3. Haptoglobin

Question 19

Function and color of ceruloplasmin

Answer 19

-Ceruloplasmin is a blue alpha-2 globulin
1. Copper transport in blood
2. Ferroxidase activity

Question 20

Wilson disease

Answer 20

Very low blood levels of ceruloplasmin as hepatic copper binding is deficient. Apoceruloplasmin (without copper) is released into the blood where it is degraded.

Question 21

“Kayser-Fleischer rings” are present in which disease

Answer 21

Wilson disease
-Damage due to copper accumulation in the liver, leakage into the blood and deposits in brain, eyes, kidney and skin
-Hepatic dysfunction, neurologic and psychiatric symptoms

Question 22

Haptoglobin

Answer 22

An alpha-2 globulin that binds to free hemoglobin dimers in the blood and prevents loss of Hb in urine.
-Haptoglobin-hemoglobin complex is taken up by macrophages. This explains why acute hemolysis leads to a low serum level of free haptoglobin.

Question 23

The beta-globulin fraction

Answer 23

1. Transferrin
2. Hemopexin
3. LDL (beta-lipoprotein)

Question 24

Transferrin

Answer 24

A beta-globulin which transports ferric iron in blood between: intestine, liver, bone marrow and spleen
-Low transferrin saturation is found in patients with iron deficiency as fewer sites of transferrin are filled.
-High transferrin saturation is found in patients with iron overload (High serum iron leads to increased binding)

Question 25

Function of hemopexin

Answer 25

Hemopexin is a beta-globulin that binds to free heme in the blood and prevents the loss of heme-iron

Question 26

Antibody found in bloom and lymph and it is the first antibody to be produced in response to an antigen (infection)

Answer 26

IgM

Question 27

(Smallest and most common) is found in all body fluids. It is produced by repeated exposure to the same antigen. IgG can cross the placenta giving passive immunity to the fetus and newborn

Answer 27

IgG

Question 28

Is found in the lung, skin, mucous membranes and secreted in allergic reactions

Answer 28

IgE

Question 29

Is found in body secretions and protects body surfaces. It is the main antibody found in human milk

Answer 29

IgA

Question 30

IgD

Answer 30

Role in serum is uncertain

Question 31

Multiple Myeloma

Answer 31

Tumor of the plasma cells and is an example of monoclonal gammopathy. -Characterized by the presence of high amounts of a single type of immunoglobulin produced by a malignant clone of the cell.

Question 32

The hepatic acute phase reaction

Answer 32

An overall positive response to prevent damage following an injury such as in: -Infections -Extreme stress -Burns -Major crush injury -Allergy or other

Question 33

Positive acute-phase reactants

Answer 33

Serum proteins that are synthesized in larger amount as they reduce inflammation and deprive microbes of iron. Examples: 1. apha1-Antitrypsin 2. Ceruloplasmin 3. Haptoglobin 4. Hemopexin 5. Alpha-2 macroglobulin

Question 34

Negative acute-phase reactants

Answer 34

Serum proteins that are synthesized in smaller amount in order to preserve amino acids for the increased synthesis of positive acute phase reactants. Examples: 1. Albumin 2. Transcortin 3. Retinol-binding protein 4. Transferrin

Question 35

C-reactive protein (CRP)

Answer 35

-A hepatic acute phase reactant that does not lead to a peak in SPEP -Synthesized and released during inflammation and was first found in the blood of patients with acute inflammation. CRP was named after the fact that it reacted with the C-polypeptide of pneumococcus.