Effect of human interleukin-2 from different sources on lymphocyte and airway beta-adrenoceptor function

The effect of recombinant human interleukin-2 (rh IL-2, Genzyme, yeast derived) on the beta-adrenoceptor function of human peripheral blood mononuclear cells (PBMC), guinea pig splenic lymphocytes and isolated guinea pig tracheal spirals was investigated. Rh IL-2 (Genzyme, yeast derived) induces a dose dependent inhibition of the isoprenaline-stimulated cAMP production in PBMC and splenic lymphocytes after a two hour preincubation period. The inhibition is significant at 0.01 U/ml IL-2 and reaches a maximum at 1 U/ml amounting 81 +/- 8% and 76 +/- 6% for human PBMC and guinea pig splenic lymphocytes respectively. The sensitivity of isolated guinea pig tracheal spirals to isoprenaline is also significantly decreased after a two hour preincubation period with 1 U/ml rh IL-2 (Genzyme, yeast derived). In contrast, rh IL-2 (Cetus, bacteria derived) does not affect the beta-adrenoceptor function of human PBMC, guinea pig splenic lymphocytes and isolated tracheal spirals, after a two-hour preincubation period. Furthermore, human cell-line derived IL-2 (Jurkat, Genzyme) also does not influence human PBMC beta-adrenoceptor function. It can therefore be concluded that IL-2 does not affect lymphocyte and airway beta-adrenoceptor function after a two hour preincubation period. The inhibition of beta-adrenoceptor function by yeast derived rh IL-2 (Genzyme) is therefore probably not related to IL-2.