Comparison of anti-TNF alpha autoantibodies in plasma and from EBV transformed lymphocytes of autoimmune and normal individuals.

To examine the ability of normal and autoimmune individuals to produce circulating anti-TNF alpha antibodies, plasma samples from 10 RA patients, 10 SLE patients and 5 normal subjects were assessed for anti-TNF alpha antibody. While every individual tested demonstrated circulating IgM anti-TNF alpha antibody, IgG anti-TNF alpha autoantibody was seen predominantly in autoimmune patients. Only 1 of 5 normal individuals, but 15 of 20 autoimmune individuals had plasma IgG anti-TNF alpha antibodies. To examine the ability of normal and autoimmune individuals to produce anti-TNF alpha autoantibody from their circulating lymphocytes, EBV transformation was performed. Oligoclonal immortal cell lines were successfully established from 13 patients and each one secreted detectable IgM anti-TNF alpha autoantibody. Transformed cells from only 1 of 5 normal individuals secreted IgM anti-TNF alpha autoantibody. These results indicate a higher prevalence of anti-TNF alpha autoantibody production among autoimmune individuals although normal individuals are also capable of producing these autoantibodies.