Quantitation of monoclonal immunoglobulins by immuno-isoelectric focusing and its application for monitoring secretory B cell neoplasia

<p>A scheme for quantitation of serum and urinary paraproteins is described using isoelectric focusing and scanning densitometry. Paraproteins could be quantified using this system when present at concentrations ranging from 1 mg/ml to 26 mg/ml, depending on the immunoglobulin class.</p> <p>The relevance of these results to monitoring secretory B cell neoplasia andthe distinction between monoclonal gammopathy of undetermined significance and myeloma is discussed.</p&gt

The incidence of monoclonal gammopathy in a population over 45 years old determined by isoelectric focusing

Immuno-isoelectric focusing (IIEF), a technique previously shown to be sensitive for the detection of paraproteinaemia, was used to test 200 individuals over the age of 45, without history of B cell neoplasm, for the presence of serum paraproteinaemia. 11% of these individuals had evidence of paraproteinaemia detectable by IIEF compared with only 2% by zonal and immunoelectrophoresis. A further 12% had oligoclonal immunoglobulins and the remainder had no qualitative abnormality of the immunoglobulin profile. These results are discussed with particular reference to the aetiology, diagnosis and monitoring of potential B cell neoplasm in high risk individuals or groups