Practical 7: Serum Protein Electrophoresis Flashcards
What is electrophoresis?
A method of separating proteins based on their physical properties
How is electrophoresis carried out?
Serum is placed on a specific medium and a charge is applied
The net charge and the size and shape of the protein are used to separate and differentiate the various serum proteins
What are the two main types of proteins present in serum?
Albumin
Globulins
How many peaks are there in SPE?
Five peaks
List the peaks in order from left to right
Albumin
a1
a2
B
gamma globulins (y)
List the peaks in order of height
Albumin, y-globulins, a2, B, a1
How do you interpret an electrophoretogram?
(2)
The height of the peak relates ot the amount of protein
The width of the band relates to the identification of the protein -> narrow = similar group of proteins, wide = dissimilar group of protein
How many globulin categories are represented on an electrophoretogram?
a1
a2
B1
B2
gamma
How can albumin be broken down in infection?
Albumin can be broken down to provide amino acids for antibodies
Why is the albumin band so discrete?
This is because albumin is formed by a non polymorphic gene
Is albumin closer to the cathode or anode?
Albumin is closest to the anode
What does a thin, high gamma globulin region indicate?
Monoclonal antibody response -> myeloma?
What does a broad, high gamma globulin region indicate?
Polyclonal antibody response -> infection
Describe the a1 band
Pale band
Very low peak
Bit of a smear
Not narrow
Describe the a2 region
Higher and more narrow peak than a1
What does a smear result from?
Result of a group of similar but not identical proteins which have similar physical properties such as charge and size
Name a molecule found in a1
a1 antitrypsin
Name a molecule found in a2
a2 macroglobulin
Name a molecule found in B
Trasferrin
B lipoprotein
How is an SPE carried out?
(7)
Cellulose acetate strip is placed over solid support
Strip has positive and negative markings
Buffer is used to pass a current of 200V through for 30mins
Ponceau stain -> binds to strip + protein
De-stain with 5% glacial acetic acid
Stain lifted from strip but not proteins
Proteins stained
Where might a monoclonal gamma region be seen?
In healthy patients over 60/70
In cancer
What is M protein?
Monoclonal protein
Produced by plasma cells
Multiple myeloma is seen in what antibodies?
IgG
IgA
What type of monoclonal gammopathy is associated with IgM?
Waldenstrom’s macroglobulinemia
