Beta-2 globulin
What it measures, and what changes the number.
Beta-2 globulin is one of the protein bands on serum protein electrophoresis, which separates blood proteins by their movement in an electric field. The beta-2 band contains mainly complement component C3, part of the immune system, and some immunoglobulins such as IgA. This line gives the absolute amount, typically calculated from the band percentage and total protein.
It is read with the neighbouring fractions, especially beta-1 and gamma globulin, and with albumin and total protein as part of the full electrophoresis pattern.
Serum is required, since fibrinogen in plasma can overlap this region. Complement C3 breaks down as a sample ages, so delayed or poorly stored samples can change the band. Some methods report a single beta fraction instead. Reports may show it as Beta 2 globulinas.
Often read alongside: Beta-2 globulin %, Beta-1 globulin, Gamma globulin, Total protein, Albumin