Autoantibodies of the IgM Class against a Human Myeloma Protein IgE(DES). I. Occurrence

Abstract

We report on the natural occurrence of human serum antibodies with specificity for a human monoclonal myeloma IgE(DES). These antibodies were of the IgM class, based on their susceptibility to reduction, sedimentation in sucrose gradients, gel filtration and inhibition of agglutination by anti-IgM antiserum. Auto-antibody levels were studied in several groups of patients by particle-counting immunoassay using latex particles to which purified monoclonal IgE(DES) was coupled. Only sera of patients suffering from parasitosis had significantly higher levels (p < 0.0005) than those of healthy blood donors. Cord sera had very low levels, followed by an age-dependent increase during early infancy. There was no relation (p > 0.10) between serum IgE and IgM antibody level. On the other hand, significant relations between IgM anti-IgE(DES) levels and serum IgM (p < 0.0005), serum IgA (p < 0.001) and serum IgG (p < 0.05) were observed suggesting that high levels were caused by or related to polyclonal activation of the immune system.