Oligoclonal band
Marker in blood/cerebrospinal fluid testing / From Wikipedia, the free encyclopedia
Oligoclonal bands (OCBs) are bands of immunoglobulins that are seen when a patient's blood serum, or cerebrospinal fluid (CSF) is analyzed. They are used in the diagnosis of various neurological and blood diseases. Oligoclonal bands are present in the CSF of more than 95% of patients with clinically definite multiple sclerosis.[1]
Two methods of analysis are possible: (a) protein electrophoresis, a method of analyzing the composition of fluids, also known as "SDS-PAGE (sodium dodecyl sulphate polyacrylamide gel electrophoresis)/Coomassie blue staining", and (b) the combination of isoelectric focusing/silver staining. The latter is more sensitive.[2]
For the analysis of cerebrospinal fluid, a sample is first collected via lumbar puncture (LP). Normally it is assumed that all the proteins that appear in the CSF, but are not present in the serum, are produced intrathecally (inside the central nervous system). Therefore, it is normal to subtract bands in serum from bands in CSF when investigating CNS diseases. A sample of blood serum is usually obtained from a clotted blood sample taken around the time of the LP.