Effect of total lymphoid irradiation on IgE antibody responses in rheumatoid arthritis and systemic lupus erythematosus.

Thirteen patients with rheumatoid arthritis and four patients with systemic lupus erythematosus and nephritis were treated with total lymphoid irradiation because of severe disease refractory to other forms of treatment. Serum samples before and after irradiation were tested for changes in total serum IgE and for changes in specific IgE antibodies to ryegrass pollen, dust mite, cat dander, and Alternaria. There were no statistically significant changes in total or specific IgE from lymphoid irradiation in these patients. The therapy caused a significant decrease in circulating total lymphocyte and Leu-3 (helper/inducer) T-lymphocyte counts. Therefore, reduction in circulating levels of helper/inducer T cells does not appear to influence preexisting levels of IgE antibodies.