Influence of specific immunotherapy on the activity of human T lymphocyte Kv1.3 voltage-gated potassium channels in insect venom allergic patients.

Kv1.3 channels play an important role in T lymphocytes function. CD4(+) and CD4(+)CD25(+) T cells are two broad categories of T cells that are critically involved in the immunoresponse to allergens and that are also a major target for allergen immunotherapy. The aim of the study was to evaluate the effects of venom immunotherapy (VIT) on the activity of Kv1.3. channels on noncultured subsets: CD4(+) and CD4(+)CD25(+) T cells of insect venom allergic patients. Eleven patients with allergic reactions to bee or wasp venoms participated in the study. The patients were provided VIT according to the ultrarush protocol. CD4(+) and CD4(+)CD25(+) T cells were isolated from peripheral blood mononuclear cells of VIT-treated patients by an immunomagnetic method. We used the whole-cell patch clamp technique to investigate the whole potassium chord conductance (gK) of Kv1.3. channels in CD4(+) and CD4(+)CD25(+) T cells of venom-sensitive patients before and during the course of VIT. The conductance of Kv1.3. channels on CD4(+)CD25(+) T cells decreased during the course of VIT. On day 0 it was 0.054 ± 0.07 [nS], and on day 70 it was 0.008 ± 0.09 [nS] (P = 0.03). The observed decrease of the gK of the Kv1.3 channels in the subpopulation of activated T cells may contribute to T cell tolerance and functional unresponsiveness of these cells to allergen in the early stages of VIT.