Determination of IL6, IL1, and IL4 in the plasma of patients with multiple myeloma.

Interleukin 6 (IL6) plasma levels were measured in 63 patients with multiple myeloma and 8 individuals with benign monoclonal gammopathy. 15 of these 71 samples showed by an enzyme linked immunosorbent assay (ELISA) detectable levels that ranged from 5 to 107 pg of IL6/ml. The IL6 levels of patients with multiple myeloma did not differ significantly from those of normal individuals (N = 25, range 5-27 pg IL6/ml) (Student's t-test, p = 0.295). The samples were negative for IL4; 3 were found positive for IL1 beta. A correlation between IL6, IL4 and IL1 beta levels and disease status was not observed for this group of patients.