A method to detect the in vitro modification of serum beta-2-microglobulin in health and disease.

The electrophoretically fast moving form of beta-2-microglobulin (alpha-B2m) was shown by crossed immunoelectrophoresis to be produced in vitro after incubation at room temperature and was not present in freshly drawn sera. A radioisotopic assay was developed to measure this conversion to alpha-B2m in sera from 14 healthy individuals and from 208 patients with benign and malignant disease. The activity was present in all the sera tested and the levels were significantly higher in sera from patients with small cell lung cancer, prostate cancer and in childhood lymphomas when compared to the level in normal sera.