ITCH AND INFLAMMATION-INDUCED BY INTRADERMALLY INJECTED INTERLEUKIN-2IN ATOPIC-DERMATITIS PATIENTS AND HEALTHY-SUBJECTS

To explore the pruritogenic and inflammatory effects of cytokines, a s ingle dose of 20 mu g recombinant human interleukin-2 was injected int radermally into eight patients with atopic dermatitis and eight health y controls, The study was double-blind and randomized with glucose as a negative control, The effects were evaluated by recording local itch and erythema over 72 h and by examining skin biopsies taken at 24 h a nd 72 h. In patients and controls, interleukin-2 provoked a low-intens ity local itch with maximal intensity between 6 h and 48 h and erythem a with maximal extension between 12 h and 72 h. In the atopic dermatit is patients, these reactions tended to appear earlier and were less pr onounced than in the healthy controls, Interleukin-2 induced dermal mo nonuclear cell infiltrates consisting mainly of CD3(+) cells. A majori ty of the T cells were CD4(+). The number of dermal CD25(+), HLA-DR(+) and ICAM-1(+) cells was also increased at the interleukin-2 injection sites, In the epidermis, interleukin-2 induced spongiosis and exocyto sis as well as HLA-DR(+) and ICAM-1(+) keratinocytes, The microscopic findings tended to be more prominent at 72 h than at 24 h in both grou ps, but with a somewhat slower onset in the atopic dermatitis patients , In conclusion, a single intradermal injection of interleukin-2 induc ed local itch, erythema, dermal T-cell infiltrates, spongiosis, exocyt osis and activation of keratinocytes both in atopic dermatits patients and in healthy controls.