RUSH IMMUNOTHERAPY RESULTS IN ALLERGEN-SPECIFIC ALTERATIONS IN LYMPHOCYTE FUNCTION AND INTERFERON-GAMMA PRODUCTIONI IN CD4(-CELLS() T)

Background: Allergen immunotherapy results in a number of changes in c linical, inflammatory, and immunologic parameters. However; the basis for the specificity of this form of therapy is unknown, especially in the context of changes in T- and B-lymphocyte function after desensiti zation to specific allergens. Objective:This study was designed to det ermine the immunologic consequences of rush immunotherapy. Methods: We studied 10 patients who had positive skin test responses to the house dust mite Dermatophagoides pteronyssinus (Dpt) and eat dander extract . Each received rush immunotherapy to mite, but mot cat dander, over a 2- to 4-week period until maintenance was achieved. Patients were eva luated before and when maintenance was achieved for skin Best and nasa l reactivity to mite and cat dander; antibody levels to the allergen w ere monitored, as were lymphocyte proliferative responses and cytokine production. Results: Rush immunotherapy to house dust mite resulted i n a significant reduction in skin and nasal reactivity to mite allerge n, but not to cat allergen, in 10 of a 10 patients. This was accompani ed by a rise in serum anti-Dpt IgE, whereas anti-cat IgE was not alter ed (7 of 7 patients). In seven of seven patients there was an Increase in anti-Dpt IgG(4) levels. T-cell proliferative responses to mite ant igen were suppressed, and numbers of CD8(+) T cells increased in frequ ency. There was a marked increase In interferon-gamma production parti cularly by CD4(+) T cells in 10 of 10 patients, The correlation betwee n the increases in interferon-gamma production and the changes in cuta neous reactivity was highly significant. Conclusion: We show that rush immunotherapy is immunologically specific in eliciting changes in T- and B-cell responses to the desensitization antigen. The specificity a nd potential benefit of immunotherapy may be linked to the increase in interferon-gamma production by allergen-activated CH4(+) T lymphocyte s.