Evaluation of immune parameters (including specific IgG4) during immunotherapy.

A group of 26 patients with allergic asthma and rhinitis, exclusively sensitized to house dust and mites, underwent immunotherapy with an extract of Dermatophagoides pteronyssinus (Allpyral) for a period of 36 months. Every 6 months we carried out a clinical examination and assessed IgE levels, specific IgE to house dust and mites, histamine release curve to house dust and mites, CD3+ CD4+ CD8+ lymphocyte subpopulations, anti-Dermatophagoides pteronyssinus specific IgG and anti-Dermatophagoides pteronyssinus specific IgG4. The results did not show any significant differences in the IgE levels pre therapy and those monitored every 6 months. However, the anti-Dermatophagoides pteronys-sinus specific IgE generally registered a decrease during hyposensitization when compared with the levels obtained before the therapy. The histamine release curve to house dust and mites registered superior histamine release percentages pre immunotherapy to those obtained after 36 months of treatment. The T subpopulations did not show any statistically significant differences at any of the times they were monitored. The assessment of anti-Dermatophagoides pteronyssinus specific IgG did not yield any significant differences in the levels pre, during or at the end of the hyposensitizing period. The study of the levels of anti-Dermatophagoides pteronyssinus specific IgG4 showed a mean overall increase between 6 and 24 months of immunotherapy. When separately comparing these increases in specific IgG, with the clinical course no relationship was found between the increase in these antibodies and levels of the "in vivo" assessment scale.(ABSTRACT TRUNCATED AT 250 WORDS)