Production of interleukin 10 and transforming growth factor [beta] in concomitant allergy and autoimmunity

BACKGROUND: The immunologic relationship between T(H)1-type autoimmune disorders and T(H)2-type allergic disorders and the role of T-cell regulation in humans is as yet unclear. The regulatory cytokine production capacity of individuals with concomitant allergy and T(H)1-type autoimmunity may provide insight into the role of T-cell regulation in both disorders. OBJECTIVES: To examine the production capacity of interleukin 10 (IL-10) and transforming growth factor beta (TGF-beta), 2 regulatory cytokines, in individuals with concomitant allergic rhinitis and T(H)1-type autoimmune diagnoses and to compare that capacity with that in individuals with allergic rhinitis only and individuals with neither diagnosis. METHODS: Seventeen case subjects and 17 age-, sex-, and ethnicity-matched controls with allergic rhinitis only were recruited from an allergy clinic. Fourteen matched controls with neither diagnosis were recruited from the general population. Peripheral blood mononuclear cells were obtained and cultured with and without mitogen stimulation (lipopolysaccharide and phytohemagglutinin). Cytokine levels from culture supernatants were measured by enzyme-linked immunosorbent assay. RESULTS: Cases with allergic rhinitis and autoimmune diseases had significantly lower unstimulated day 3 IL-10 levels compared with controls with allergic rhinitis only (P = .05) and significantly lower stimulated day 5 TGF-beta levels compared with controls with neither diagnosis (P = .02). Cases had consistently lower regulatory capacity compared with both control groups, as measured by an additive index using IL-10 and TGF-beta levels. CONCLUSION: Individuals with concomitant allergic rhinitis and T(H)1-type autoimmune disorders have a lower regulatory cytokine production capacity than individuals with allergic rhinitis only and those with neither diagnosis.